Preference for feed bins shared with cows of the same or different parity and relationships with feeding behavior and feed efficiency

Our objectives were to (1) evaluate cows' preferences for visiting feed bins limited to either same- versus mixed-parity social interactions, depending on their parity; (2) examine the effect of parity and bin social dynamic type on competition behavior and feeding patterns, and (3) investigate cow-level relationships between feed bunk competition behavior, feeding patterns, and feed efficiency. Twenty-eight primiparous and 28 multiparous (2.4 ± 0.6 lactations) lactating Holstein cows (127.8 ± 30.1 and 145.3. ± 10.4 DIM, respectively) were housed in a freestall pen with 28 roughage intake control bins (2:1 stocking density). Each cow was assigned to 2 bins, including 1 shared with 3 other cows of the same parity (SM) and 1 with 3 cows of mixed parities (MX, 50% primiparous and 50% multiparous). Feed bunk competition was recorded via video in the first hour after morning feed delivery for 2 d, and feeding patterns were recorded from 24-h roughage intake control data. Residual feed intake was calculated as the difference between predicted and observed dry matter intake after accounting for known energy sinks. Based on the first visit to the feed bunk after fresh feed delivery, multiparous cows tended to prefer the MX bin compared with the SM one; cows showed no other overall preference for bin type based on number of visits. Over time, multiparous cows remained consistent in their magnitude of preference for visiting each bin type, but involvement in competition was not consistent over time. Primiparous cows tended to be involved in more total competitive contacts and ate faster at the SM bin compared with the MX one. Those primiparous cows who visited the SM bin more often within the first hour after morning feed delivery tended to be less feed efficient. Multiparous cows initiated more successful replacements after a displacement at the MX versus SM bin, with no difference in feeding patterns between bin types. Regardless of parity or bin type, visiting the bunk sooner after feed delivery was correlated with involvement in more competitive interactions and more time eating within the first 30 min. Consuming more feed during a longer first visit to the bunk after fresh feed delivery was correlated with being less feed efficient. Overall, when given the choice of feeding from bins shared with cows of the same or mixed parities at a 2:1 stocking density, primiparous cows showed differences in behavior between those bin types, with implications for feed efficiency; these effects are perhaps an unintended consequence of compensatory strategies to avoid direct competition with multiparous cows.

Farm-level risk factors associated with increased milk β-hydroxybutyrate and hyperketolactia prevalence on farms with automated milking systems

The objectives of this study were to determine the farm-level hyperketolactia (HKL) prevalence, as diagnosed from milk β-hydroxybutyrate (BHB) concentration, on dairy farms milking with an automatic milking system (AMS) and to describe the farm-level housing, management, and nutritional risk factors associated with increased farm-average milk BHB and the within-herd HKL prevalence in the first 45 DIM. Canadian AMS farms (n = 162; eastern Canada n = 8, Quebec n = 23, Ontario n = 75, western Canada n = 55) were visited once between April to September 2019 to record housing and herd management practices. The first test milk data for each cow under 45 DIM were collected, along with the final test of the previous lactations for all multiparous cows, from April 1, 2019 to September 30, 2020. The first test milk BHB was then used to classify each individual cow as having HKL (milk BHB ≥ 0.15 mmol/L) at the time of testing. Milk fat and protein content, milk BHB, and HKL prevalence were summarized by farm and lactation group (all, primiparous, and multiparous). During this same time period, formulated diets for dry and lactating cows, including ingredients and nutrient composition, and AMS milking data were collected. Data from the AMS were used to determine milking behaviors and milk production of each herd during the first 45 DIM. Multivariable regression models were used to associate herd-level housing, feeding management practices, and formulated nutrient composition with first test milk BHB concentrations and within-herd HKL levels separately for primiparous and multiparous cows. The within-herd HKL prevalence for all cows was 21.8%, with primiparous cows having a lower mean prevalence (12.2 ± 9.2%) than multiparous cows (26.6 ± 11.3%). Milk BHB concentration (0.095 ± 0.018 mmol/L) and HKL prevalence for primiparous cows were positively associated with formulated prepartum DMI and forage content of the dry cow diet while being negatively associated with formulated postpartum DMI, the major ingredient in the concentrate supplemented through the AMS, and the PMR-to-AMS concentrate ratio. However, multiparous cows' milk BHB concentration (0.12 ± 0.023 mmol/L) and HKL prevalence were positively associated with the length of the previous lactation, milk BHB at dry off, prepartum diet nonfiber carbohydrate content, and the major forage fed on farm, while tending to be negatively associated with feed bunk space during lactation. This is the first study to determine the farm-level risk factors associated with herd-level prevalence of HKL in AMS dairy herds, thus helping optimize management and guide diet formulation to promote the reduction of HKL prevalence.

Comparison of three mathematical models to estimate lactation performance in dairy cows

Milk yield dynamics and production performance reflect how dairy cows cope with their environment. To optimize farm management, time-series of individual cow milk yield have been studied in the context of precision livestock farming, and many mathematical models have been proposed to translate raw data into useful information for the stakeholders of the dairy chain. To gain better insights on the topic, this study aimed at comparing 3 recent methods that allow to estimate individual cow potential lactation performance, using daily data recorded by the automatic milking systems of 14 dairy farms (7 Holstein, 7 Italian Simmental) from Belgium, the Netherlands, and Italy. An iterative Wood model (IW), a perturbed lactation model (PLM), and a quantile regression (QR) were compared in terms of estimated total unperturbed (i.e., expected) milk production and estimated total milk loss (relative to unperturbed yield). The IW and PLM can also be used to identify perturbations of the lactation curve and were thus compared in this regard. The outcome of this study may help a given end-user in choosing the most appropriate method according to their specific requirements. If there is a specific interest in the post-peak lactation phase, IW can be the best option. If one wants to accurately describe the perturbations of the lactation curve, PLM can be the most suitable method. If there is need for a fast and easy approach on a very large data set, QR can be the choice. Finally, as an example of application, PLM was used to analyze the effect of cow parity, calving season, and breed on their estimated lactation performance.

Behavioral consistency of competitive behaviors and feeding patterns in lactating dairy cows across stocking densities at the feed bunk

Introduction

High feed bunk stocking densities can differentially impact individual dairy cows' competitive behaviors, feeding patterns, and feed efficiency. Our objective was to manipulate feed bunk stocking densities to evaluate intra-individual behavioral consistency across stocking densities and quantify associations with feed efficiency and production.

Methods

Thirty-two primiparous (130.7 ± 29.0 days in milk, DIM) and 32 multiparous (111.3 ± 38.3 DIM) lactating Holstein cows were housed with 32 roughage intake control (RIC) bins. Each cow was assigned to share 8 bins with others of the same parity and similar body weight (16 cows/block; 2:1 feed bunk stocking density except during tests). Competition and feeding patterns were evaluated via video and RIC data, respectively, at 3 stocking densities (1:1, 2:1, 4:1 cows/bin) during 1-h tests (2 tests/stocking density; 6 tests/cow) following 2 h feed deprivation. Residual feed intake (RFI) was calculated across the 45-d study as the difference between observed and predicted dry matter intake (DMI) after accounting for known energy sinks. Linear mixed models were used to evaluate the overall impact of test stocking density on competition and feeding patterns. To evaluate intra-individual consistency between stocking densities, individual stability statistic (ISS) scores were computed. Correlational relationships were determined between RFI and ISS scores.

Results and dicsussion

Cows displayed the most competitive behaviors at 2:1 stocking density (p < 0.0001) but experienced the highest rate of contacts per minute of eating time at 4:1 (1:1 vs. 2:1 vs. 4:1: 0.09 vs. 0.95 vs. 1.60 contacts/min; p < 0.0001). Feeding patterns were modulated as stocking density increased; eating rate increased (0.16 vs. 0.18 vs. 0.22 kg/min; p < 0.001) as eating time (40.3 vs. 28.2 vs. 14.6 min; p < 0.001) and DMI decreased (6.3 vs. 5.1 vs. 3.0 kg; p < 0.001). As stocking density doubled, individuals remained consistent (p = 0.018) in time spent near others actively eating and tended to remain consistent in competition behavior and feeding patterns (0.053 ≤ p ≤ 0.094). Between 2:1 and 4:1, cows with higher DMI and milk production were more consistent in first-visit DMI and duration. Feed efficiency was not associated with behavioral consistency across the tests (p ≥ 0.14). Nonetheless, feed bunk stocking density has behavioral implications which should be considered in nutritional management decisions.

Effects of extending dairy cow longevity by adjusted reproduction management decisions on partial net return and greenhouse gas emissions: A dynamic stochastic herd simulation study

Prolonging dairy cattle longevity is regarded as one of the options to contribute to more sustainable milk production. Since failure to conceive is one of the main reasons for culling, this study investigates how adjustments in reproduction management affect partial net return at herd level and greenhouse gas emissions per unit of milk, using a dynamic stochastic simulation model. The effects of reproduction decisions that extend cattle longevity on milk yield, calving interval and pregnancy rate were derived from actual performance of Dutch commercial dairy cows over multiple lactations. The model simulated lactations, calving and health status events of individual cows for herds of 100 cows. Scenarios evaluated differed in the maximum number of consecutive artificial insemination (AI) attempts (4, 5 or 6 services), or the production threshold (20, 15, or 10 kg milk per day) at which cows that failed to conceive are culled (reproductive culling). Annual partial net return was computed from revenues of sold milk, calves and slaughtered cows, and the costs from feed consumption, rearing replacement heifers, AI services and treatment for clinical mastitis and lameness. Greenhouse gas emissions were computed for feed production, enteric fermentation, and manure management, and were expressed as total CO2 equivalents. Average age at culling increased with an increased maximum number of AI services. This increase was larger when going from a maximum of 4 to 5 AI attempts (108 d) than from a maximum of 5 to 6 attempts (47 d). Similarly, the average age at culling increased from 1,968 to 2,040 and 2,132 d when the threshold for reproductive culling decreased from 20, to 15 and 10 kg milk per day, respectively. Average annual partial net return increased by 1.1% from €165,850 per 100 cows at a maximum of 4 AIs to €167,670 per 100 cows at a maximum of 6 AIs, and increased by 4.3% from €161,210 per 100 cows at a reproductive culling threshold of 10 kg/day to €168,190 per 100 cows at a threshold of 20 kg/day. Greenhouse gas emissions decreased by 1.2% from 0.926 to 0.915 kg CO2 equivalents per kg fat-and-protein-corrected milk (FPCM) with an increase in a maximum number of AIs from 4 to 6 AIs. Conversely, greenhouse gas emissions increased by 0.2% from 0.926 kg at a threshold of reproductive culling of 20 kg/day to 0.928 kg CO2 equivalents per kg FPCM at a threshold of 10 kg/day. Although lowering the threshold for reproductive culling has the potential to extend cattle longevity more than increasing the maximum number of AI services, only the increase in AI services benefits a farm's partial net return, while reducing greenhouse gas emissions.

Combined Metabolomics and Biochemical Analyses of Serum and Milk Revealed Parity-Related Metabolic Differences in Sanhe Dairy Cattle

The production performance of dairy cattle is closely related to their metabolic state. This study aims to provide a comprehensive understanding of the production performance and metabolic features of Sanhe dairy cattle across different parities, with a specific focus on evaluating variations in milk traits and metabolites in both milk and serum. Sanhe dairy cattle from parities 1 to 4 (S1, n = 10; S2, n = 9; S3, n = 10; and S4, n = 10) at mid-lactation were maintained under the same feeding and management conditions. The milk traits, hydrolyzed milk amino acid levels, serum biochemical parameters, and serum free amino acid levels of the Sanhe dairy cattle were determined. Multiparous Sanhe dairy cattle (S2, S3, and S4) had a greater milk protein content, lower milk lactose content, and lower solids-not-fat content than primiparous Sanhe dairy cattle (S1). Moreover, S1 had a higher ratio of essential to total amino acids (EAAs/TAAs) in both the serum and milk. The serum biochemical results showed the lower glucose and total protein levels in S1 cattle were associated with milk quality. Furthermore, ultra-high-resolution high-performance liquid chromatography with tandem MS analysis (UPLC-MS/MS) identified 86 and 105 differential metabolites in the serum and milk, respectively, and these were mainly involved in amino acid, carbohydrate, and lipid metabolism. S1 and S2/S3/S4 had significantly different metabolic patterns in the serum and milk, and more vitamin B-related metabolites were significantly higher identified in S1 than in multiparous cattle. Among 36 shared differential metabolites in the serum and milk, 10 and 7 metabolites were significantly and strongly correlated with differential physiological indices, respectively. The differential metabolites identified were enriched in key metabolic pathways, illustrating the metabolic characteristics of the serum and milk from Sanhe dairy cattle of different parities. L-phenylalanine, dehydroepiandrosterone, and linoleic acid in the milk and N-acetylornithine in the serum could be used as potential marker metabolites to distinguish between Sanhe dairy cattle with parities of 1-4. In addition, a metabolic map of the serum and milk from the three aspects of carbohydrates, amino acids, and lipids was created for the further analysis and exploration of their relationships. These results reveal significant variations in milk traits and metabolites across different parities of Sanhe dairy cattle, highlighting the influence of parity on the metabolic profiles and production performance. Tailored nutritional strategies based on parity-specific metabolic profiles are recommended to optimize milk production and quality in Sanhe cattle.

Behavioural variability, physical activity, rumination time, and milk characteristics of dairy cattle in response to regrouping

In the commercial dairy industry worldwide, it is common practice to periodically regroup cows as part of their management strategy within housed systems. While this animal husbandry practice is intended to improve management efficiency, cows may experience social stress as a result of the social environment changes, which may have an impact on their behavioural patterns, performance, and welfare. We investigated whether regrouping altered dairy cows' behaviour and impacted their cortisol concentration (a physiological marker of stress), oxytocin, milk yield, and quality in a robotic milking system. Fifty-two lactating cows (17 primiparous; 35 multiparous) were moved in groups of 3-5 individuals into established pens of approximately 100 cows. Behaviour of the regrouped cows was directly observed continuously for 4 h/day across 4-time blocks (day-prior (d-1), day-of regrouping (d0), day-after (d + 1), and 6-days after (d + 6) regrouping). Cows were categorised as being with others, alone, or feeding every 2.5 min prior to the assessment of behavioural dynamics. Milk yield (MY) and composition, total daily activity, and rumination time (RUM) data were extracted from the Lely T4C management program (Lely Industries, Maassluis, the Netherlands), and milk samples were collected for cortisol and oxytocin concentration analyses; data were analysed using linear mixed-effect modelling. Primiparous cows were less likely to be interacting with others on d + 1 than d-1 compared with multiparous. However, average bout duration (minutes) between being alone and feeding activity states were similar on d-1, d + 1, and d + 6, for both primiparous and multiparous cows. A reduction in the average alone and feeding bout duration was observed on d0. Multiparous cows spent significantly more total time being alone on d0 compared to d-1. Neither regrouping nor parity statistically influenced milk DM content, energy, or cortisol concentration. Primiparous cows produced 3.80 ± 2.42 kg (12.2%) less MY on d + 1 compared to their d-1, whereas multiparous cows did not change MY. A significant decrease of 0.2% fat was found in both parity groups following regrouping and remained low up to d + 6. Daily activity in both parity groups increased significantly and RUM reduced after regrouping. A significant decrease in oxytocin concentration was observed in all cows on d + 1. The results, specifically for primiparous cows, indicated a negative impact of regrouping on social interactions, due to changes in the social environment which may lead to short-term social instability. Multiparous cows may benefit from previous regrouping experiences.

Vaginal temperature of lactating cows during heat waves or normal summer day and effect of additional daily cooling treatments as heat load mitigation strategy

The vaginal temperature (VT) of lactating Holstein cows was monitored in not heat wave (NHW) and in heat wave (HW) summer days. Temperature humidity index (THI) was monitored and assigned to four classes of heat load (HL): THI < 68 null; 68 < THI < 74 low; 74 < THI < 80 moderate; and THI > 80 high.Five daily treatments consisting of continuous forced ventilation and sprayed water (1' on follow by 5' off) were assumed as control cooling protocol (CC) and compared with two experimental cooling protocols (EC) applied in the feed bunk and based on the CC plus two additional cooling treatments which lasted a total of 90' (EC90) or 150' (EC150) in the day.Sixty lactating cows were enrolled in two summer trials carried out in NHW or HW. In each trial, 10 cows were cooled by CC, 10 by EC90 and 10 by EC150. Twenty additional cows were monitored in a fall trail to have reference value of THI and VT under thermoneutral conditions (TN). Each trial lasted 72 h, and measurements of VT were carried out by intra-vaginal data loggers.The 33% of observed THI was within the high class of HL during HW, whereas THI never exceeded the upper threshold of moderate or low class of HL in NHW and TN, respectively.Multiparous and high yielding cows were more sensitive to HL, and the increased daily cooling treatments reduced heat load during hot conditions. However, during heat waves a certain degree of hyperthermia occurred even with intensive cooling management based on seven daily treatments.

Postpartum hair cortisol, dehydroepiandrosterone sulfate and their ratio in beef cows: Exploring association with parity and conception outcome

Hair steroid measurement has received increasing attention for monitoring hypothalamic-pituitary-adrenal axis function, as it offers the advantages of being noninvasive, fast, and able to indicate steroid concentrations over long periods. The objects of the study were to evaluate cortisol (C) and dehydroepiandrosterone sulfate (DHEA-S) hair concentrations and their ratio (C/DHEA-S) in beef cows from calving to 100 days (d) postpartum (pp) and to assess possible differences related to parity (primiparous vs multiparous) and conception outcome (pregnant vs not pregnant). Hair samples were collected from 6 primiparous and 5 multiparous pregnant beef cows by clipping the coat at calving (T0) and every 20 d for 5 times (T1-T5), collecting only the regrown hair. Starting from the 6th-week pp, cows were submitted to artificial insemination at spontaneous estrus; by 100 d pp, 7 cows were pregnant and 4 were not pregnant. Statistical analysis showed higher hair C concentrations in the 11 cows at calving (T0) compared to all the subsequent samplings except for T1, and higher C concentrations at T1 compared to T3, T4, and T5. These results indicate that hair C concentrations in beef cows are affected by sampling time, with a decrease from calving, as reported in other matrices. When exploring changes within parity groups, no differences were found in the multiparous among sampling times, while hair C concentrations at T0 and T1 tended to be higher than at T2 (0.01 ≤ p < 0.05) and were higher (p < 0.01) than in all the subsequent samplings (T3, T4 and T5) within the primiparous group. Higher hair C concentrations were found at T0 and T1 in the primiparous compared to multiparous (p < 0.01), suggesting that primiparous cows undergo a greater stress level before and around parturition compared to multiparous, probably due to the novelty of the calving experience. No differences were detected in C hair concentrations according to conception outcome (pregnant versus not pregnant) in each sampling time. Hair DHEA-S concentrations were neither affected by time nor by parity or conception outcome. Differences in the C/DHEA-S ratio were found at T1, with higher C/DHEA-S in the multiparous compared to primiparous cows (p < 0.001), and a tendency for higher ratio in the not pregnant compared to the pregnant (0.01 ≤ p < 0.05). These results support the choice of hair as a valuable biological matrix when investigating long-time periods such as postpartum in cows and suggest an enhanced immunoprotective effect of DHEA-S in the postpartum of primiparous cows, and in cows that get pregnant within 100 d postpartum.

Social interactions, feeding patterns, and feed efficiency of same- and mixed-parity groups of lactating cows

Social dynamics in group-housed animals can have important effects on their welfare, feed efficiency, and production potential. Our objectives were to: (1) evaluate the effects of parity and social grouping on competition behavior, feeding patterns, and feed efficiency, and (2) investigate cow-level relationships between competition and feeding behavior, production, and feed efficiency. Fifty-nine Holstein cows (144.5 ± 21.8 starting days in milk, mean ± SD) were housed in a freestall pen with 30 Roughage Intake Control (RIC) bins. We evaluated the effects of parity (primiparous [PR, n = 29] vs. multiparous [MU, n = 30]) and group composition at the feed bunk (same-parity [SM, n = 39] vs. mixed-parity [MX, n = 20, 50% of each parity]) with a 2 × 2 factorial design (SM-MU: n = 20; SM-PR: n = 19; MX-MU: n = 10; MX-PR: n = 10) on competition behavior, feeding patterns, and feed efficiency. Within the pen, groups of 9 to 10 cows were considered subgroups and assigned to treatments defined by sets of 5 assigned bins (2:1 stocking density). Feed bunk competition and feeding patterns were recorded via continuous video in the first hour after morning feed delivery and 24-h RIC data, respectively. Residual feed intake (RFI) was calculated as the difference between predicted and observed dry matter intake (DMI) after accounting for known energy sinks. Linear models were used to evaluate the effects and interactions of parity and group composition on competition, feeding behavior, and feed efficiency. Within-cow correlations were performed between competition, feeding behavior, and RFI. Cows in MX, compared with SM, were involved in more competitive interactions [mean (95% CI): competitive contacts: 11.5 (8.1, 16.3) vs. 7.2 (5.5, 9.3) events; displacements: 4.0 (3.0, 5.3) vs. 2.1 (1.7, 2.7) events, and replacements: 3.5 (2.6, 4.7) vs. 1.9 (1.5, 2.5) events]. Cows in MX vs. those in SM had more bunk visits/meal ( 4.3 [3.9, 4.8] vs. 3.7 [3.4, 3.9] visits/meal) and longer meals (31.2 vs. 27.4 ± 0.9 min/meal) and tended to have higher RFI (0.41 ± 0.3 vs. -0.21 ± 0.2) and were therefore less feed efficient. Multiparous versus PR cows had greater DMI per day (29.3 ± 0.6 vs. 25.5 ± 0.4 kg/d) and per meal (4.2 [4.0, 4.4] vs. 3.4 [3.2, 3.6] kg/meal), faster eating rates (0.14 [0.13, 0.15] vs. 0.12 [0.11, 0.13] kg/min), and fewer bunk visits/d (26.6 [24.0, 29.4] vs. 32.8 [29.7, 35.9]). Regardless of grouping or parity, cows with shorter latencies to first visit the bunk after feed delivery were involved in more competition and tended to be less feed efficient. Overall, individual cow- and group-level relationships among competition, feeding behavior, and feed efficiency play an important role in feed bunk social dynamics. At a competitive 2:1 stocking density, mixed-parity groups for lactating cows may have potentially negative animal welfare and feed efficiency implications that should be considered when selecting grouping strategies on the farm.

Sensor-based behavioral patterns can identify heat-sensitive lactating dairy cows

Heat stress impairs the health and performance of dairy cows, yet only a few studies have investigated the diversity of cattle behavioral responses to heat waves. This research was conducted on an Italian Holstein dairy farm equipped with precision livestock farming sensors to assess potential different behavioral patterns of the animals. Three heat waves, defined as at least five consecutive days with mean daily temperature-humidity index higher than 72, were recorded in the farm area during the summer of 2021. Individual daily milk yield data of 102 cows were used to identify "heat-sensitive" animals, meaning the cows that, under a given heat wave, experienced a milk yield drop that was not linked with other health events (e.g., mastitis). Milk yield drops were detected as perturbations of the lactation curve estimated by iteratively using Wood's equation. Individual daily minutes of lying, chewing, and activity were retrieved from ear-tag-based accelerometer sensors. Semi-parametric generalized estimating equations models were used to assess behavioral deviations of heat-sensitive cows from the herd means under heat stress conditions. Heat waves were associated with an overall increase in the herd's chewing and activity times, along with an overall decrease of lying time. Heat-sensitive cows spent approximately 15 min/days more chewing and performing activities (p < 0.05). The findings of this research suggest that the information provided by high-frequency sensor data could assist farmers in identifying cows for which personalized interventions to alleviate heat stress are needed.

Effect of sustained release bolus oral administration on body condition change, blood parameters, and uterine health in primiparous cows under heat stress

The transition period is very stressful for primiparous cows due to their first calving experience and will be more challenging if it occurs under heat stress conditions. Heat stress reduces the feed intake of dairy cows. Therefore, it reduces the consumption of minerals and vitamins. Oral administration of boluses through the provision of mineral-vitamin compounds can reduce metabolic abnormalities after calving. The present study aimed to evaluate effect of sustained-release bolus on body condition score (BCS) change, serum metabolites, uterine health, and reproductive status in primiparous cows. Heifers were selected at the beginning of the close-up period (n = 60, BCS = 3.35 ± 0.12). There were 2 experimental treatments at the time of calving: (1) heifers without bolus oral administration (H - Bo, n = 30); (2) heifers with bolus oral administration (H + Bo, n = 30). The results showed that although the rate of BCS loss was lower in the group receiving bolus, the effect of bolus was not significant. The effect of bolus on blood level of glucose, non-esterified fatty acids (NEFA), and beta-hydroxybutyrate (BHBA) was not significant; however, the highest concentration of albumin (P = 0.05) was observed in the H + Bo group on day 42 after calving. The concentration of aspartate transaminase (AST) tended to increase (P = 0.06) on day 14 after calving and entire the study. Total antioxidant capacity (TAC) was affected (P < 0.05) by bolus throughout the period of study, and the highest (P < 0.05) concentration of glutathione peroxidase (GPX) and superoxide dismutase (SOD) was observed in H + Bo group on day 42 after calving. The H + Bo group had the lowest (P < 0.05) vaginal discharge score (VDS). In general, oral administration of the sustained-release bolus in heifers significantly affected the antioxidant factors and uterine health, as well as had positive effects on liver function, body condition, and reproduction status.

Metabolic and physiological adaptations to first and second lactation in Holstein dairy cows: Postprandial patterns

Dairy cows during their first and second lactation have different milk yield, body development, feed intake, and metabolic and endocrine statuses. However, large diurnal variations can also exist in terms of biomarkers and hormones related to feeding behavior and energy metabolism. Thus, we investigated the diurnal patterns of the main metabolic plasma analytes and hormones in the same cows during their first and second lactations in different stages of the lactation cycle. Eight Holstein dairy cows were monitored during their first and second lactation, during which they were reared under the same conditions. Blood samples were collected before the morning feeding (0 h) and after 1, 2, 3, 4.5, 6, 9, and 12 h on scheduled days between -21 d relative to calving (DRC) and 120 DRC for the assessment of some metabolic biomarkers and hormones. Data were analyzed using the GLIMMIX procedure of SAS (SAS Institute Inc.). Regardless of parity and stage of lactation, glucose, urea, β-hydroxybutyrate, and insulin peaked a few hours after the morning feeding, whereas nonesterified fatty acids decreased. The insulin peak was attenuated during the first month of lactation, whereas postpartum growth hormone spiked on average 1 h after the first meal in cows during their first lactation. This peak occurred earlier than during the second lactation. Most of the differences in diurnal trends between lactations were observed in the postpartum period (and in some cases even in early lactation). Glucose and insulin were higher during the first lactation throughout the day, and the differences increased 9 h after feeding. Conversely, nonesterified fatty acids and β-hydroxybutyrate showed the opposite trend, and their plasma concentrations at 9 and 12 h after feeding differed between lactations. These results confirmed the differences observed between the first 2 lactations in prefeeding metabolic marker concentrations. Furthermore, plasma concentrations of investigated analytes showed high variability during the day, and thus we advise caution when interpreting metabolic biomarker data in dairy cows, especially during the periods close to calving.

Change in Rumination Behavior Parameters around Calving in Cows with Subclinical Ketosis Diagnosed during 30 Days after Calving

We hypothesized that cows with SCK (blood BHB over >1.2 mmol/L) diagnosed within the first 30 days of calving can be predicted by changes in rumination and activity behavioral parameters in the period before calving and indeed subsequently. A total of 45 cows were randomly selected from 60 dry cows from at least 40 days before calving. All the cows were fitted with RuniWatch sensors monitoring both intake behaviors (faceband) and general movement and activity behavior (pedometer) (RWS-ITIN + HOCH, Switzerland). Following an adaptation period of 10 days, rumination, eating, and activity parameters were monitored for 30 days before calving and 30 days after calving. Considering the design of the study, we divided the data of cows into three stages for statistical evaluation: (1) the last thirty days before calving (from day -30 to -1 of the study); (2) day of calving; and (3) the first thirty days after calving (from day 1 to 30 of the study). We found that before calving, those cows with a higher risk of having SCK diagnosed after calving had lower rumination time, eating time, drinking gulps, bolus, chews per min, chews per bolus, downtime, maximal temperature, and activity change. On the calving day, in cows with higher risk of SCK after calving, we found lower rumination time, eating time, chews per min, chews per bolus, uptime, downtime, minimal temperature, other chews, eating chews, drinking time, drinking gulps, activity, average temperature, maximal temperature, activity change, rumination chews, and eating chews. After calving in cows with SCK, we found lower rumination time, eating time 1, eating time 2, bolus, chews per bolus, uptime, downtime, minimal temperature, maximal temperature, rumination chews, and eating chews. Moreover, after calving we found higher drinking gulps, drinking time, activity, activity change, average temperature, other chews, and eating chews in cows with SCK. From a practical point of view, we recommend that by tracking changes in rumination and activity behavior parameters registered with RuniWatch sensors (such as rumination time, eating time, drinking time, drinking gulps, bolus, chews per minute, chews per bolus, downtime, maximal temperature, and activity change) before, during, and after calving, we can identify cows with a higher risk of SCK in the herd.

Feeding behavior in relation to ovarian cyclicity in cows with no or a short dry period

The objective of this study was to investigate relations between feeding behavior (FB) variables focusing on intake of the basal ration during 3 wk prepartum until 3 wk postpartum, and postpartum onset of luteal activity (OLA) in dairy cows subjected to no (0-d) or a short (30-d) dry period (DP). Feeding behavior of the basal ration intake (concentrate intake excluded) was continuously recorded by computerized feeders for 123 dairy cows and analyzed from 3 wk prepartum to 3 wk postpartum. Cows were subjected to a DP length: 0-d DP (n = 81), or 30-d DP (n = 42). Milk progesterone concentration was determined 3 times per week until 100 DIM to determine OLA, which was classified as early OLA (<21 DIM) and late OLA (≥21 DIM). Relations between FB and OLA class were analyzed using mixed models. During 3 wk prepartum, FB differed between parity class (parity 2 or ≥3 after calving). Cows with a 30-d DP prepartum, regardless of their OLA class, had more visits per meal, higher meal duration, total meal time, total daily feeding time, and lower feed intake and feeding rate compared with cows with 0-d DP. During the first 2 d postpartum, cows with OLA <21 had more visits per day and visits per meal compared with cows with OLA ≥21. During the first 3 wk postpartum, cows within the 30-d DP group with OLA <21 had greater meal size, feed intake, and feeding rate compared with cows with OLA ≥21 of this group. Cows within the 0-d DP group with OLA <21 had higher meal duration, total daily meal time, total daily feeding time, and meal size, but a lower feeding rate compared with cows with OLA ≥21 of this group. Concluding from the current study, cows with OLA <21 had a postpartum FB that reflected a cow with faster recovery from parturition and better adaptation to onset of lactation compared with OLA ≥21. No or a short DP affected prepartum FB, suggesting that prepartum management affects FB. This study provides evidence of different FB between cows with different timing of resumption of ovarian cyclicity.

A first time for everything: The influence of parity on the behavior of transition dairy cows

Over the last 20 years an increasing amount of research has described how dairy cow behavior changes during the few weeks before and after parturition, also known as the transition period. Dairy cows experience several challenges during this period, including pain associated with pregnancy and labor, social stressors associated with pen moves, changes in diet, and navigating new routines that include daily milking in a parlor or automatic milking system. For cows calving for the first time ("primiparous"), these experiences may be particularly challenging compared with those animals who have calved previously ("multiparous"). The objectives of this review are to (1) summarize the research to date on behavioral differences between primiparous and multiparous animals during the transition period, (2) describe the effect of management practices, such as regrouping and milking, on primiparous animals, and (3) suggest management recommendations and future directions for research focused on the behavior of primiparous cows.

Effect of lameness on feeding behavior of zero grazed Jersey dairy cows

The dairy industry faces major challenges with high levels of lameness, in parallel to an increased consumer focus on animal welfare. This encourages farmers to consider more robust breeds, such as Jersey cows. As little is known about the behavior of this breed under loose housing conditions, the present study sought to describe the feeding behavior of lame and non-lame Jersey cows in different parities. Such breed-specific information of behavioral changes is needed for breed-specific herd management decisions and may contribute to identifying animals that are susceptible to developing lameness in the future, thus reducing impacts on the welfare and production of cows. Feeding data from 116 Danish Jersey cows were collected using automatic feeders, and lameness status was assessed by technicians every second week. The cows were kept in a loose housing system, with cubicles, a slatted concrete floor, and automatic milking robots. Eating time per visit and per day, the number of visits per day, and intervals between meals were analyzed using generalized linear mixed effects models. The effect of lameness was not significant for any variable. Primiparous Jersey cows had significantly longer eating times per day, shorter meal intervals, and a lower number of visits per day than older Jersey cows. Week in lactation affected the eating time per visit and per day, the number of visits, and between-meal intervals. In conclusion, we found no differences between lame and non-lame Jersey cows but between parities, which disagree with previous research on other breeds, suggesting that Jersey cows not just differ in size and looks but also in their behavioral reaction when lame. Although data from only one herd of a research center were used, this study has demonstrated the need for further research about breed-specific differences and their implications for the health and welfare of the animals.

Heat stress in a temperate climate leads to adapted sensor-based behavioral patterns of dairy cows

Most research on heat stress has focused on (sub)tropical climates. The effects of higher ambient temperatures on the daily behavior of dairy cows in a maritime and temperate climate are less studied. With this retrospective observational study, we address that gap by associating the daily time budgets of dairy cows in the Netherlands with daily temperature and temperature-humidity index (THI) variables. During a period of 4 years, cows on 8 commercial dairy farms in the Netherlands were equipped with neck and leg sensors to collect data from 4,345 cow lactations regarding their daily time budget. The time spent eating, ruminating, lying, standing, and walking was recorded. Individual cow data were divided into 3 data sets: (1) lactating cows from 5 farms with a conventional milking system (CMS) and pasture access, (2) lactating cows from 3 farms with an automatic milking system (AMS) without pasture access, and (3) dry cows from all 8 farms. Hourly environment temperature and relative humidity data from the nearest weather station of the Dutch National Weather Service was used for THI calculation for each farm. Based on heat stress thresholds from previous studies, daily mean temperatures were grouped into 7 categories: 0 = (<0°C), 1 = (0-12°C, reference category), 2 = (12-16°C), 3 = (16-20°C), 4 = (20-24°C), 5 = (24-28°C), and 6 = (≥28°C). Temperature-humidity index values were grouped as follows: 0 = (THI <30), 1 = (THI 30-56, reference category), 2 = (THI 56-60), 3 = (THI 60-64), 4 = (THI 64-68), 5 = (THI 68-72) and 6 = (THI ≥72). To associate daily mean temperature and THI with sensor-based behavioral parameters of dry cows and of lactating cows from AMS and CMS farms, we used generalized linear mixed models. In addition, associations between sensor data and other climate variables, such as daily maximum and minimum temperature, and THI were analyzed. On the warmest days, eating time decreased in the CMS group by 92 min/d, in the AMS group by 87 min/d, and in the dry group by 75 min/d compared with the reference category. Lying time decreased in the CMS group by 36 min/d, in the AMS group by 56 min/d, and in the dry group by 33 min/d. Adaptation to daily temperature and THI was already noticeable from a mean temperature of 12°C or a mean THI of 56 or above, when dairy cows started spending less time lying and eating and spent more time standing. Further, rumination time decreased, although only in dry cows and cows on AMS farms. With higher values for daily mean THI and temperature, walking time decreased as well. These patterns were very similar for temperature and THI variables. These results show that dairy cows in temperate climates begin to adapt their behavior at a relatively low mean environmental temperature or THI. In the temperate maritime climate of the Netherlands, our results indicate that daily mean temperature suffices to study the effects of behavioral adaptation to heat stress in dairy cows.

Effects of Parity and Stage of Lactation on Trend and Variability of Metabolic Markers in Dairy Cows

Simple Summary

The rise in milk yield per cow, herd size, and the percentage of primiparous cows in dairy herds increasingly requires optimized health management in order to ensure the health of the cows. The transition period (three weeks before to three weeks after calving) has a key role in health problems, because dairy cows undergo tremendous metabolic changes. Metabolic monitoring provides an in-depth insight into how the cows cope with these challenges. A remarkable variability in the metabolic parameters reflects the adaptation of dairy cows during the transition from pregnancy to lactation. In addition, primiparous cows undergo physical adaptations because of growth, first gestation, the maturation of the mammary glands, the onset of lactation, and fighting for social dominance. Previous studies have rarely considered these specific demands due to the influences of parity and the lactation stage. Thus, the objective of our study was to describe the variation in metabolic parameters due to parity and the stage of lactation based on a huge number of primiparous and multiparous cows, observed at all stages of lactation, in a retrospective analysis of laboratory data. The remarkable impact of both parity and lactation was elucidated for most parameters. This should be taken into account for a correct interpretation of the laboratory diagnostics in the framework of metabolic monitoring.

Abstract

Metabolic monitoring is a tool that is helpful with the increasing requirements regarding feeding and health management in dairy herds. This study aimed at describing the trend and variability of different biochemical parameters in blood and urine in relation to the stages of lactation and parity, in a retrospective analysis of laboratory data from clinically healthy German Holstein cows. The results were derived from metabolic monitoring in Thuringia (Germany), during 2009–2019. A total of 361,584 measured values, of 13 different metabolic variables, were assigned to parity (primiparous and multiparous) and stage of lactation (10 classes from −30 to 300 days in milk). The Kruskal–Wallis test was applied for the evaluation of differences regarding parity or the stage of lactation. Non-esterified fatty acids, beta hydroxybutyrate, and the activity of aspartate aminotransferase in serum were clearly affected by parity and lactation. Serum concentrations of cholesterol, bilirubin, and phosphorus, as well as the serum activity of glutamate dehydrogenase, were affected by the stage of lactation, while parity impacted urea concentration. The serum activity of creatine kinase, serum concentrations of calcium, and urine concentrations of net acid base excretion, potassium, and sodium were not affected by parity or lactation. In conclusion, specific reference limits, with respect to parity and the stage of lactation, are necessary.

Associations of Wearable Sensor Measures With Feed Intake, Production Traits, Lactation, and Environmental Parameters Impacting Feed Efficiency in Dairy Cattle

Feed efficiency is an important trait to dairy production because of its impact on sustainability and profitability. Measuring individual cow feed intake on commercial farms would be unfeasibly costly at present. Thus, developing cheap and portable indicators of feed intake would be highly beneficial for genetic selection and precision feeding management tools. Given the growing use of automated sensors on dairy farms, the objective of this study was to determine the relationship between measurements recorded from multiple wearable sensors and feed intake. A total of three different wearable sensors were evaluated for their association with dry mater intake (DMI). The sensors measured activity (sensors = 3), rumination (sensors = 1), ear temperature (sensors = 1), rumen pH (sensors = 1) and rumen temperature (sensors = 1). A range of 56–340 cows with assorted sensors from 24 to 313 days in milk (DIM) were modeled to evaluate associations with DIM, parity, and contemporary group (CG; comprised of pen and study cohort). Models extending upon these variables included known energy sinks (i.e., milk production, milk fat/protein and metabolic body weight), to characterize the association of sensors measures and DMI. Statistically significant (i.e., P &lt; 0.05) regression coefficients for individual sensor measures with DMI ranged from 9.01E-07 to −3.45 kg DMI/day. When integrating all measures from a single sensor in a model, estimated regression coefficients ranged 8.83E-07 to −3.48 kg DMI/day. Significant associations were also identified for milk production traits, parity, DIM and CG. Associations tended to be highest for timepoints around the time of feeding and when multiple measurements within a sensor were integrated in a single model. The findings of this study indicate sensor measures are associated with feed intake and other energy sink traits and variables impacting feed efficiency. This information would be helpful to improve feed and feeding efficiency on commercial farms as proxy measurements for feed intake.

Sensor based time budgets in commercial Dutch dairy herds vary over lactation cycles and within 24 hours

Cows from 8 commercial Dutch dairy farms were equipped with 2 sensors to study their complete time budgets of eating, rumination, lying, standing and walking times as derived from a neck and a leg sensor. Daily sensor data of 1074 cows with 3201 lactations was used from 1 month prepartum until 10 months postpartum. Farms provided data over a 5 year period. The final models (lactational time budget and 24h time budget) showed significant effects of parity, farm and calving season. When primiparous cows were introduced in the lactational herd, they showed a decrease in lying time of 215 min (95% CI: 187–242) and an increase in standing time of 159 min (95% CI: 138–179), walking time of 23 min (95% CI: 20–26) and rumination time of 69 min (95% CI: 57–82). Eating time in primiparous cows increased from 1 month prepartum until 9 months in lactation with 88 min (95% CI: 76–101) and then remained stable until the end of lactation. Parity 2 and parity 3+ cows decreased in eating time by 30 min (95% CI: 20–40) and 26 min (95% CI: 18–33), respectively, from 1 month before to 1 month after calving. Until month 6, eating time increased 11 min (95% CI: 1–22) for parity 2, and 24 min (95% CI: 16–32) for parity 3+. From 1 month before calving to 1 month after calving, they showed an increase in ruminating of 17 min (95% CI: 6–28) and 28 min (95% CI: 21–35), an increase in standing time of 117 min (95% CI: 100–135) and 133 min (95% CI: 121–146), while lying time decreased with 113 min (95% CI: 91–136) and 130 min (95% CI: 114–146), for parity 2 and 3+, respectively. After month 1 in milk to the end of lactation, lying time increased 67 min (95% CI: 49–85) for parity 2, and 77 min (95% CI: 53–100) for parity 3+. Lactational time budget patterns are comparable between all 8 farms, but cows on conventional milking system (CMS) farms with pasture access appear to show higher standing and walking time, and spent less time lying compared to cows on automatic milking system (AMS) farms without pasture access. Every behavioral parameter presented a 24h pattern. Cows eat, stand and walk during the day and lie down and ruminate during the night. Daily patterns in time budgets on all farms are comparable except for walking time. During the day, cows on CMS farms with pasture access spent more time walking than cows on AMS farms without pasture access. The average 24h pattern between parities is comparable, but primiparous cows spent more time walking during daytime compared to older cows. These results indicate a specific behavioral pattern per parameter from the last month prepartum until 10 months postpartum with different patterns between parities but comparable patterns across farms. Furthermore, cows appear to have a circadian rhythm with varying time budgets in the transition period and during lactation.

Comparison of the feeding behaviour of primiparous and multiparous Jersey and Holstein cows kept under equal conditions throughout lactation

The objective of the study was to describe the feeding behaviour of primiparous and multiparous Jersey cows compared to Holstein cows housed in separate groups in the same barn. Such information could help farmers to optimise management with respect to welfare and production. Yet, it remains limited for Jersey cows over the entire period of lactation. Feeding data of 116 Danish Jersey (mean parity 2.14 ± 1.32) and 218 Danish Holstein cows (mean parity 1.90 ± 1.16) were assessed using automatic feeders from day 15 to 252 of lactation. Total eating duration, duration of eating per visit, intervals between meals, number of visits per day and the eating rate were analysed using linear mixed effects models. The cows were kept in a loose-housing system, with cubicles and automatic milking robots, and the group composition was dynamic. Compared to Holstein cows, Jersey cows visited the feeder significantly more often with shorter between meal intervals. However, the visit duration and total daily eating time and eating rates were significantly shorter for Jersey cows. There was no difference between breeds in the daily eating time and eating rate of older cows. Younger Jersey cows had significantly lower eating rates than older Jersey cows. No other difference in parity was found within Jersey cows. Weeks in milk significantly affected the eating time per day, number of visits per day and eating rate. The trajectories of outcome variables during lactation did not differ between the two breeds. In conclusion, we found substantial differences in the feeding behaviour of Jersey and Holstein cows, however, these differences could also be related to a group effect.

The Transition Period Updated: A Review of the New Insights into the Adaptation of Dairy Cows to the New Lactation

Recent research on the transition period (TP) of dairy cows has highlighted the pivotal role of immune function in affecting the severity of metabolic challenges the animals face when approaching calving. This suggests that the immune system may play a role in the etiology of metabolic diseases occurring in early lactation. Several studies have indicated that the roots of immune dysfunctions could sink way before the “classical” TP (e.g., 3 weeks before and 3 weeks after calving), extending the time frame deemed as “risky” for the development of early lactation disorders at the period around the dry-off. Several distressing events occurring during the TP (i.e., dietary changes, heat stress) can boost the severity of pre-existing immune dysfunctions and metabolic changes that physiologically affect this phase of the lactation cycle, further increasing the likelihood of developing diseases. Based on this background, several operational and nutritional strategies could be adopted to minimize the detrimental effects of immune dysfunctions on the adaptation of dairy cows to the new lactation. A suitable environment (i.e., optimal welfare) and a balanced diet (which guarantees optimal nutrient partitioning to improve immune functions in cow and calf) are key aspects to consider when aiming to minimize TP challenges at the herd level. Furthermore, several prognostic behavioral and physiological indicators could help in identifying subjects that are more likely to undergo a “bad transition”, allowing prompt intervention through specific modulatory treatments. Recent genomic advances in understanding the linkage between metabolic disorders and the genotype of dairy cows suggest that genetic breeding programs aimed at improving dairy cows’ adaptation to the new lactation challenges (i.e., through increasing immune system efficiency or resilience against metabolic disorders) could be expected in the future. Despite these encouraging steps forward in understanding the physiological mechanisms driving metabolic responses of dairy cows during their transition to calving, it is evident that these processes still require further investigation, and that the TP—likely extended from dry-off—continues to be “the final frontier” for research in dairy sciences.

Calving Management: A Questionnaire Survey of Veterinary Subject Matter Experts and Non-Experts

Simple Summary

We designed a questionnaire and asked two groups of veterinarians: (1) subject matter experts, who had published on calving management and (2) veterinary practitioners) for their opinion about aspects of calving management. Participants recommended to differentiate between the two stages of parturition and emphasized signs of imminent parturition, such as “restlessness” and “visibility of fetal parts”. There was no consensus on the right time to move the cow to the maternity pen. Almost half of the respondents recommended a 6-h observation interval for prepartum cows in the maternity pen. The two veterinary groups differed little in their knowledge of calving management.

Abstract

Accurate detection of the onset of parturition is a key factor in the prevention of dystocia. In order to establish current best practice recommendations for calving management, we asked subject matter experts (SME) who had published on calving management (by online survey, n = 80) and non-SMEs, veterinary practitioners (by workshop survey, n = 24) for their opinions. For this, we designed a questionnaire on the significance of signs of imminent parturition (SIP), the frequency of calving observation, and influencing factors for the timing of cow movement to a maternity pen. The response rate was 67.5% in the online survey and 100% in the workshop survey. The majority (89.7%) of all respondents agreed that it is beneficial for successful calving management to differentiate between stage I and II of parturition. Of 12 signs of imminent parturition (for stage I and II), “restlessness” and “visibility of fetal parts in vulva” were cited by 56.5% and 73.3% of SME and non-SME respondents, respectively. There was no consensus on the right time to move the cow to the maternity pen; recommendations varied from one to over 21 days. Almost half of the respondents (45.7%) recommended a 6-h observation interval for prepartum cows in the maternity pen. This study identified a strong consensus on the SIP and how and when to observe cows prior to parturition. SMEs and non-SMEs provided broadly similar recommendations, while the SMEs and the non-SMEs differed significantly in the number of publications on calving they authored, they differed little in their knowledge of calving management.

Postpartum Stressors Cause a Reduction in Mechanical Brush Use in Dairy Cows

Dairy cows are often subjected to multiple post-partum stressors but how these stressors impact cows' affective states remain poorly understood. Negative affective states are often associated with reduced expression of low-resilience behaviors, so we explored whether cows would reduce their use of a brush after calving. Before calving, cows were offered the opportunity to use a mechanical brush once a week for 10 min. In Experiment 1, we explored whether cows reduced their use of a mechanical brush after parturition (compared to prepartum values) when subjected to the myriad of stressors typically experienced by cows at this time. In Experiment 2, we assessed the effect of cow-calf separation. Results from Experiment 1 showed that cows displayed a reduced brush use following parturition compared to the week before calving. In Experiment 2, we showed that cows given more time to bond with their calf, and who were separated more recently from their calf, showed a more pronounced reduction in brush use. Cows provided part-time contact with their calf for 29 days also reduced their brush use when they were permanently separated from their calf on day 30 after calving. These results suggest that cows experienced anhedonia and point to new directions for research on dairy cow affective states.

Effects of feeding rumen-protected linseed fat to postpartum dairy cows on plasma n-3 polyunsaturated fatty acid concentrations and metabolic and reproductive parameters

High-yielding dairy cows experience a negative energy balance and inflammatory status during the transition period. Fat supplementation increases diet energy density, and plasma n-3 polyunsaturated fatty acids (PUFA) have been proposed to improve immune function. This study tested the hypothesis that dietary supplementation with a rumen-protected and n-3 PUFA-enriched fat could ameliorate both the energetic deficit and immune status of postpartum high-yielding dairy cows, improving overall health and reproductive efficiency. At 11 d in milk (DIM), cows were randomly allocated to groups (1) n-3 PUFA (n = 29), supplemented with encapsulated linseed oil supplying additional up to 64 g/d (mean 25 ± 4 g/d) of α-linolenic acid (ALA), or (2) control (n = 31), supplemented with hydrogenated palm oil without ALA content. Fat supplements of the n-3 PUFA and control groups were available through an automated, off-parlor feeding system, and intake depended on the cow's feeding behavior. Plasma ALA concentrations were higher in n-3 PUFA than control cows, following a linear relation with supplement ingestion, resulting in a lower n-6/n-3 ratio in plasma. Metabolic parameters (body condition score and glucose and β-hydroxybutyric acid blood concentrations) were unaffected, but milk yield improved with increased intake of fat supplements. Plasma total adiponectin concentrations were negatively correlated with ingestion of n-3 PUFA-enriched fat supplement, following a linear relation with intake. Conception rate to first AI increased with higher intake of both fats, but a decrease of calving-to-conception interval occurred only in n-3 PUFA cows. Postpartum ovarian activity and endometrial inflammatory status at 45 DIM were unaffected. In conclusion, this study evinced a positive linear relation between rumen-protected linseed fat intake and plasma n-3 PUFA concentrations, which modulated adiponectin expression and improved reproductive parameters.

Genetic and seasonal variations of Trypanosoma theileri and the association of Trypanosoma theileri infection with dairy cattle productivity in Northern Japan

Trypanosoma theileri is considered a non- or low-pathogenic trypanosome that generally causes latent infection in apparently healthy cattle; however, T. theileri propagates in the bloodstream and may cause clinical disease in pregnant animals or co-infection with bovine leukemia virus or Theileria orientalis. In the current study, a monthly survey of T. theileri infection over one year was carried out in a research dairy farm in Hokkaido, Japan to determine the 1) seasonal variations in the prevalence, 2) genetic characterization of T. theileri, and 3) associations of milk and blood parameters in dairy cattle with T. theileri infection, including data of metabolic profile tests and dairy herd performance tests, using linear mixed models. We found that 1) the prevalence of T. theileri infection was significantly higher in summer and winter than in other seasons; 2) T. theileri possibly showed genetic diversity in Eastern Hokkaido; and 3) T. theileri infection was associated with significantly lower levels of blood urea nitrogen, milk protein, and solids-not-fat, which are caused by a low rumen fermentation level. This is the first study to report the negative impact of T. theileri infection in dairy cattle, and our study indicates that control of T. theileri infection can improve the productivity of dairy cattle.

Behavioral changes in dairy cows with metritis in seasonal calving pasture-based dairy system

The aims of this study were to determine changes in lying and rumination behavior of transition dairy cows that were healthy or affected by metritis during the autumn and spring calving season in a temperate climate and determine the effect of some weather variables (precipitation and heat stress) on these behaviors. A total of 103 multiparous cows were monitored during the autumn (February to April) and spring calving season (July to October) from 10 d before to 10 d after calving. Cows were chosen retrospectively by diagnosis of metritis [autumn season, (n = 11); spring season, (n = 13)] or as healthy [autumn season, (n = 25); spring season, (n = 25)] based on vaginal discharge characteristics evaluated during the first 10 days in milk. In all animals, electronic data loggers recorded lying (Hobo Pendant G Acceleration, Onset Computer Corp.) and rumination behavior (Hi-Tag rumination monitoring system, SCR Engineers Ltd.) during the study period. We included precipitation level (>1 mm/d = with rain, and ≤1 mm/d = without rain) and heat stress [no heat stress = temperature-humidity index (THI) < 68 vs. heat stress = THI ≥ 68] as weather factors that may have affected lying and rumination behavior during the spring and autumn season in a temperate climate, respectively. Metritis during the spring calving season was associated only with longer lying times (≥1.3 h/d) after calving. During the autumn calving season cows with metritis lay down longer the day of calving (~2.1 h/d) and had fewer lying bouts of longer duration during the prepartum period compared with healthy cows. Rumination time did not differ by health status during the spring calving season, whereas cows with metritis during autumn ruminated 30, 21, and 24 min/d less than healthy cows during the prepartum, calving, and postpartum period, respectively. Precipitation and heat stress were associated with decreased daily lying and rumination time in sick cows. Our results indicate that differences in lying and rumination behavior depended on the metritis status, and support the idea that weather factors such as rainfall or heat stress requires to be considered in analyses of transition cow behavior in seasonal calving pasture-based dairy systems.

Changes in the soft-tissue thickness of the claw sole in Holstein heifers around calving

Claw horn disruption lesions are a common cause of lameness in dairy cattle. It is commonly agreed that they develop due to excessive pressure from the distal phalanx on the horn-producing tissue in the sole. The distal phalanx is supported by the suspensory apparatus, a large proportion of which is made up of connective tissue. It has been hypothesized that increased laxity of the connective tissue due to hormonal changes around calving may lead to decreased support of the distal phalanx, resulting in a sinking of the bone and increased pressure on the horn-producing tissue. In this longitudinal study, our first objective was to determine whether the thickness of the soft tissue related to the claw sole (the combined depth of the digital cushion and corium; soft-tissue thickness, STT) in the weight-bearing hind claws of live heifers changed around calving (the period from approximately 3 wk before calving to 2 wk after calving). Our second objective was to evaluate the relationship between the body condition score (BCS) of recruited heifers and the STT estimates we obtained. We measured STT (defined as the distance between the distal phalanx and the sole horn) in the apex and the posterior part of the sole of the hind claws of 34 Holstein heifers 4 times over 3 to 4 wk around calving. We determined STT by ultrasonographic measurements through the sole horn on weight-bearing claws. The overall mean STT at site 1 was 3.3 mm [minimum-maximum (min-max): 1.8 to 5.2 mm], and the mean at site 2 was 3.7 mm (min-max: 2.2 to 5.8). The overall mean STT was thickest in the first examination before calving [site 1: 3.4 mm (min-max: 1.9 to 4.7); site 2: 4.1 mm (min-max: 2.7 to 5.8)] and thinnest at site 1 in the second examination after calving (3.2 mm, min-max: 1.8 to 5.2) and at site 2 at the first examination after calving (3.5 mm, min-max: 2.2 to 5.0). We observed an average reduction in STT of -0.2 mm (min-max: 0.8 to -0.9 mm) at site 1 during the study period, but we did not observe this reduction in all animals. At site 2, we found an average reduction in STT of -0.6 mm (min-max: 0.8 to -1.3 mm) from 10 d before calving to 5 d after calving, corresponding to a decrease of approximately 15% (min-max: 0 to 31%). We suggest that this reduction was caused by a rotation of the distal phalanx toward the posterior part of the sole horn in the weeks around calving. During the same period, heifer BCS decreased between 0.25 and 0.5 increments in the BCS scale, but we found no correlation between BCS and STT. However, the heifers experienced many changes related to management, feeding, and time budget during the study period, and the rotation of the distal phalanx and reduction of the STT might be explained not only by calving but also by other factors that affect heifers and their claws during the transition period.

Associations between body condition score, locomotion score, and sensor-based time budgets of dairy cattle during the dry period and early lactation

Lameness, one of the most important disorders in the dairy industry, is related to postpartum diseases and has an effect on dairy cow welfare, leading to changes in cows' daily behavioral variables. This study quantified the effect of lameness on the daily time budget of dairy cows in the transition period. In total, 784 multiparous dairy cows from 8 commercial Dutch dairy farms were visually scored on their locomotion (score of 1-5) and body condition (score of 1-5). Each cow was scored in the early and late dry period as well as in wk 4 and 8 postpartum. Cows with locomotion scores 1 and 2 were grouped together as nonlame, cows with score 3 were considered moderately lame, and cows with scores 4 and 5 were grouped together as severely lame. Cows were equipped with 2 types of sensors that measured behavioral parameters. The leg sensor provided number of steps, number of stand-ups (moving from lying to standing), lying time, number of lying bouts, and lying bout length. The neck sensor provided eating time, number of eating bouts, eating bout length, rumination time, number of rumination bouts, and rumination bout length. Sensor data for each behavioral parameter were averaged between 2 d before and 2 d after locomotion scoring. The percentage of nonlame cows decreased from 63% in the early dry period to 46% at 8 wk in lactation; this decrease was more severe for cows with higher parity. Cows that calved in autumn had the highest odds for lameness. Body condition score loss of >0.75 point in early lactation was associated with lameness in wk 4 postpartum. Moderately lame cows had a reduction of daily eating time of around 20 min, whereas severely lame cows had a reduction of almost 40 min. Similarly, moderately and severely lame dry cows showed a reduction of 200 steps/d, and severely lame cows in lactation showed a reduction of 600 steps/d. Daily lying time increased by 26 min and lying bout length increased by 8 min in severely lame cows compared with nonlame cows. These results indicate a high prevalence of lameness on Dutch dairy farms, with an increase in higher locomotion scores from the dry period into early lactation. Time budgets for multiparous dairy cows differed between the dry period and the lactating period, with a higher locomotion score (increased lameness) having an effect on cows' complete behavioral profile. Body condition score loss in early lactation was associated with poor locomotion postpartum, whereas lameness resulted in less eating time in the dry period and early lactation, creating a harmful cycle.

Provision of shelter during the prepartum period: Effects on behavior, blood analytes, and health status in dairy cows in winter

This study aimed to assess the effect of shelter provision during the prepartum period on lying, ruminating, and feeding behavior in outdoor-housed dairy cows exposed to winter weather conditions in a temperate climate. We also aimed to determine whether shelter provision during the prepartum period influenced blood analytes related to energy metabolism, body cleanliness, and health status. In this study, 2 cohorts of 12 multiparous Holstein prepartum cows were tested in winter. Twenty-five days before their expected calving date, the cows in each cohort were paired and randomly assigned to an open paddock without shelter or to one with access to an artificial shelter until calving. Shelter use, lying time, number of lying bouts, duration of lying bouts, rumination time, and feeding time were continuously recorded during the 3 wk before calving. Cows were assessed weekly for body cleanliness throughout the 3-wk prepartum period. A blood sample was taken from the coccygeal vein of each cow at wk -3, -2, -1, 1, 2, and 3 relative to calving date, and were assayed for nonesterified fatty acids (NEFA), β-hydroxybutyrate, and haptoglobin concentrations. Cases of clinical health disorders after calving were also recorded. The cows spent 60% of their daily time in the shelters, and for 75% of that time they were lying down. Cows with access to shelter during the prepartum period lay down around 3.2 h/d more than cows without shelter on wk -3 and -2 relative to calving. The cows with shelter access spent less time feeding during the morning (wk -3: 29.7 min; wk -2: 12.1 min; wk -1: 17.3 min) and afternoon (wk -3: 18.2 min; wk -2: 21.9 min) than cows without shelter access. As well, cows with shelter access showed a higher body cleanliness score (∼92 vs. ∼48%) and lower NEFA concentrations (wk -2: 0.27 vs. 0.44 mmol/L; wk -1: 0.46 vs. 0.64 mmol/L) in the precalving period, and lower haptoglobin concentrations in the first week postpartum (0.34 vs. 0.79 mg/mL) than cows without shelter access. We observed no treatment differences in daily rumination time, β-hydroxybutyrate concentrations, or postpartum health disorders. Despite the small number of dairy cows used in this study, these findings suggest that having access to a shelter during the prepartum period increases lying time, improves body cleanliness, and reduces adipose mobilization. Therefore, it is important to provide a protected area for the welfare of prepartum dairy cows exposed to winter climate conditions.

Heat stress effects in primiparous and multiparous lactating crossbred cows under a warm environment and their responses to a cooling treatment

Context In temperate climates, multiparous cows are more susceptible to heat stress (HS) than are primiparous cows. However, these differences in susceptibility may vary in warm environments, where the overall production level is lower, cow size is smaller, and adaptation to HS increases. Aim The different effects of HS and its alleviation on primiparous and multiparous cows was tested in crossbred cows (3/4 Holstein × 1/4 Brahman) in a warm environment. Method Twelve cows during the rainy season (August–September 2014) and 12 cows during the dry season (March–April 2015; six primiparous, six multiparous) were monitored for rectal temperature and respiration rate, indicators of HS, and milk yield (MY) in a dairy farm in El Salvador. Ambient temperature and relative humidity were recorded hourly to estimate temperature–humidity index throughout the day. During the rainy season, all cows were housed in a pen without cooling treatment. During the dry season, fans and sprinklers were installed in the pen and provided cooling to the herd in two 15-day periods, alternated with two periods without cooling (Control). Key results Primiparous cows were more susceptible to HS. Cooling alleviated HS, resulting in an increased feed intake and MY, with a greater impact on primiparous cows. During the cooling treatment, HS parameters increased overnight after the last cooling cycle of the day. This indicated that, despite the cooling treatment, cows still suffered from HS outside the hottest hours of the day. Furthermore, despite a higher temperature–humidity index during the rainy season, rectal temperature and MY remained similar in both the dry and the rainy season for cows without cooling, indicating that animals effectively lower their body temperature by increasing their respiration rate. Conclusions The cooling only partially helped alleviate HS in both multiparous and primiparous cows, with the effects being greater on the latter. However, the increments in MY were proportional to the increases in feed intake, indicating that the efficiency of feed utilisation was likely to be not improved. Implications More attention should be given to the susceptibility of primiparous cows to HS, as well as to the adjustment of cooling protocols towards alleviating HS in early morning and late afternoon hours.

Relation of Subclinical Ketosis of Dairy Cows with Locomotion Behaviour and Ambient Temperature

Simple Summary

The use of innovative tools and the registration of new biomarkers can help with identification of certain diseases in fresh dairy cows earlier and more accurately, thus improving the quality of treatment and reducing the losses incurred. One of the most often diagnosed diseases of postpartum cows is subclinical ketosis. According to our knowledge there exists limited information about how subclinical ketosis is related to locomotion behaviour (walking activity, feeding time with head position down, feeding time with head position up, change between activities) and average, minimal and maximal ambient temperature. We hypothesized that continuous maximal monitoring of cow locomotion behaviour (in combination with measuring the ambient temperature) could identify cows with subclinical ketosis. In addition, we hoped that changes of the above-mentioned parameters prior to clear clinical signs of subclinical ketosis would aid in earlier detection of the disease.

Abstract

Rumination time, chewing time and drinking time are indicators that can be assessed in case of cow disease. In this research, two groups of cows were formed: cows with subclinical ketosis (SCK; n = 10) and healthy cows (HG; n = 10). Behaviour such as walking activity, feeding time with head position up, feeding time with head position down, change of activity and average, minimal and maximal ambient temperature of cows were recorded by the RumiWatch noseband system (RWS; RumiWatch System, Itin+Hoch GmbH, Liestal, Switzerland). The RWS comprises a noseband halter with a built-in pressure sensor and a liquid-filled pressure tube. Data from each studied cow were recorded for 420 h. According to the results of our study, it was determined that cows diagnosed with subclinical ketosis showed a tendency to change their activity more frequently. Our data indicates that minimal and maximal ambient temperatures are related with SCK.

The effects of social environment on standing behavior and the development of claw horn lesions

The primary aim of this prospective experimental study was to evaluate how the social environment after calving influenced standing behavior in primiparous cows. At calving, primiparous cows were mixed with familiar peers in a low-stocked pen (≤33% stocking density; n = 22) or mixed with unknown older cows at 100% stocking density (n = 20). All study cows were mixed with older cows 3 wk after calving. Time spent standing and perching (standing with only the front feet in the stall) were measured d 1 to 3 after calving using 5-min scan sampling. To evaluate if the low-stocked treatment constituted a low-stress social environment, agonistic interactions at the feed barrier were measured for 90 min following feed delivery for a subsample of cows in both treatments (12 cows/treatment). The daily behavioral time budget, including the 90 min following milking, was examined for this subset of cows. A secondary aim was to assess if the social environment after calving was related to the risk of developing claw horn lesions later in lactation. Sole and white line lesions were recorded at wk 6 and 12 after calving, and cows were categorized as either having or not having at least 1 hemorrhage of severity ≥3 (scale 1 to 5) for each lesion type and assessment. Prolonged standing after regrouping was not observed, and we found no differences in standing time and time spent perching between treatments. Agonistic behaviors directed toward the focal cows occurred less frequently in the low-stocked pen compared with the control. The number and severity of sole and white line lesions increased after calving. At wk 6 postpartum there was a numeric (but not statistically significant) difference between treatments in the proportion of primiparous cows that had white line hemorrhages of severity score ≥3 (low-stress social environment: 20% vs. control: 50%). In conclusion, under the conditions of this study the social environment did not influence standing behavior, but did affect agonistic interactions and may have influenced the risk of claw horn lesions in the weeks following calving. Further studies should evaluate the relationship between the social environment and claw health.

Calving difficulty influences rumination time and inflammatory profile in Holstein dairy cows

Difficult calving may adversely affect dairy cow health and performance. Maternal:fetal disproportion is a major cause of dystocia. Therefore, the main objective of this study was to assess the effects of dam:calf body weight ratio (D:C) on calving difficulty, rumination time, lying time, and inflammatory profile in 25 Holstein dairy cows. Using automatic monitoring systems, we monitored behavior and production in 9 primiparous and 16 pluriparous cows between dry-off and 30 d in milk. During the same period, we collected blood samples to monitor metabolism and inflammatory profile of these cows. Calvings were video recorded to assess calving difficulty and observe the duration of the expulsive stage. After parturition, the cows were separated into 3 classes according to their D:C: easy (E; D:C >17), medium (M; 14 < D:C <17), and difficult (D; D:C <14). The cows in class D showed relatively longer labor durations (108 min vs. 54 and 51 min for classes D, M, and E, respectively) and higher calving assistance rates (50% vs. 0 and 11% of calvings for classes D, M, and E, respectively) than those in the other 2 classes. Compared with the cows in classes M and E, those in class D exhibited shorter rumination times on the day of calving (176 min/d vs. 288 and 354 min/d for classes D, M, and E, respectively) and during the first week of lactation (312 min/d vs. 339 and 434 min/d for classes D, M, and E, respectively) and maintained lower rumination values until 30 DIM (399 min/d vs. 451 and 499 min/d for classes D, M, and E, respectively). Primiparous class D cows had shorter resting times during the first week after calving compared with those in class M (8 vs. 11 h/d for classes D and M, respectively). Interclass differences were found in terms of the levels of inflammation markers such as acute-phase proteins (ceruloplasmin, albumin, retinol, and paraoxonase). Moreover, cows in class D had lower plasma levels of fructosamine and creatinine after calving. Low D:C reduced postcalving rumination time and increased inflammation grade, suggesting a lower welfare of these animals at the onset of lactation. The D:C might serve as a useful index for the identification of cows at relatively higher risk of metabolic and inflammatory disease, thus helping farmers and veterinarians improve the welfare and health of these cows.

The behavior of dairy cattle in the transition period: Effects of blood calcium status

The aim of this study was to use an automated behavior-monitoring system to objectively assess the association between lying and activity behavior in the precalving, calving, and postcalving periods between multiparous and primiparous cows with (1) normocalcemia, (2) subclinical hypocalcemia, or (3) clinical hypocalcemia at calving. Behavioral data and blood serum samples were collected from 51 multiparous and 21 primiparous Holstein dairy cattle. Blood samples from the coccygeal vein were taken within 24 h of calving, and serum was analyzed to measure total calcium concentration. Cows were classified into one of 3 categories: normocalcemia (serum calcium concentration ≥ 2.0 mmol/L), subclinical hypocalcemia (serum calcium concentration < 2.0 mmol/L, absence of clinical signs), and clinical hypocalcemia (clinical signs and successful treatment). An activity sensor was fitted to the right hind leg of cows 3 wk before their expected calving date. Data for lying time, standing time, number of steps, and the total number of standing and lying bouts (postural transitions) were automatically collected and summed into 15-min blocks. Behavioral variables were summarized into 2-h and 24-h periods before analyses. Mixed effect models were used to analyze cow behavior in the entire 14 d before calving (d -14 to -1), on the day of calving, and the entire 21 d postcalving (d 1 to 21). In the precalving period, multiparous cows with normocalcemia had fewer postural transitions (18.5 ± 6.9 no./d) compared with cows with subclinical hypocalcemia (23.5 ± 8.0 no./d) and clinical hypocalcemia (23.5 ± 8.6 no./d). However, there was no association between blood calcium status on lying time (min/d) or step count (no./d) for multiparous cows. For primiparous cows, the step count of cows with subclinical hypocalcemia remained constant across the period, and the step count of cows with normocalcemia decreased from 842.8 steps/d on d -14 to 427.5 steps/d on d -1. Postpartum cows with clinical hypocalcemia were less active (fewer steps) and spent 88 min/d (1.5 h) and 125 min/d (2.1 h) more time lying down compared with cows with subclinical hypocalcemia and normocalcemia, respectively. This shows that clinical hypocalcemia is associated with significant long-lasting behavioral effects on cows during the critical postpartum period.

Towards sensor-based calving detection in the rangelands: a systematic review of credible behavioral and physiological indicators

Calving is a critical point in both a cow and calf’s life, when both become more susceptible to disease and risk of death. Ideally, this period is carefully monitored. In extensive grazing systems, however, it is often not economically or physically possible for producers to continuously monitor animals, and thus, calving frequently goes undetected. The development of sensor systems, particularly in these environments, could provide significant benefits to the industry by increasing the quantity and quality of individual animal monitoring. In the time surrounding calving, cows undergo a series of behavioral and physiological changes, which can potentially be detected using sensing technologies. Before developing a sensor-based approach, it is worthwhile considering these behavioral and physiological changes, such that the appropriate technologies can be designed and developed. A systematic literature review was conducted to identify changes in the dam’s behavioral and physiological states in response to a calving event. Articles (n = 104) consisting of 111 independent experiments were assessed following an intensive search of electronic databases. Commonly reported indicators of parturition (n = 38) were identified, and temporal trend graphs were generated for 13 of these changes. The results compare trends in behavioral and physiological changes across a variety of animal-related factors and identifies several reliable indicators of parturition for detection with sensors, namely calf grooming behavior, changes in rumination duration, and lying bouts. This synthesis of literature suggests that variability exists between individuals and thus, combining several calving indicators may result in a more broadly applicable and accurate detection of parturition.

Association of postpartum uterine diseases with lying time and metabolic profiles of multiparous Holstein dairy cows in the transition period

The objective of this study was to assess how uterine disorders alter the lying behaviour and plasma biomarkers in dairy cows. 34 multiparous cows were retrospectively classified into three groups according to the first uterine disorder that cows were diagnosed with: retained placenta (RP), metritis (MET), or healthy (H; cows without any clinical disease). Lying time (LT) and duration of lying bouts (LB) were monitored between 6 weeks prior to and 8 weeks after calving via the AfiAct II pedometer. Blood samples were collected routinely between 14 days before and 28 days after calving. Data was analysed using Proc MIXED of SAS ver. 9.4. Regardless of grouping, both LT and LB were longer (P < 0.01) in the prepartum period (774 ± 16.6 min/day and 89.9 ± 2.1 min/bout) than in the first 28 days after calving (DFC; 653 ± 16.7 min/day and 63.7 ± 2.1 min/bout). Cows with RP had longer LT than healthy cows during the last 3 weeks before calving (837 ± 30.9 vs. 735 ± 27.1 min/day; P < 0.05). LT in cows with MET and healthy cows were not significantly different. The LB was similar among groups, averaging 76.1 ± 3.4 min/bout in healthy cows, 73.2 ± 3.8 min/bout in cows with RP, and 75.2 ± 3.7 min/bout in cows with MET (P > 0.05). Compared with healthy cows, cows with RP laid down longer and stood up for shorter times (P < 0.05), particularly before calving. In addition, cows with RP had increased mobilization of body stores and more pronounced inflammatory status, as demonstrated by plasma haptoglobin (P = 0.04) and albumin (P < 0.01) concentrations. Our data suggest that automatic monitoring of lying behaviour could help identify cows at increased risk of developing certain disorders, such as RP.

Periparturient stocking density affects lying and ruminating behavior and one-week-calf performance of Holstein cows

Objective

This study aimed to investigate the effect of stocking density on the behavior, productivity, and metabolism of periparturient Holstein cows as well as calf performance.

Methods

A total of 48 periparturient cows were randomly assigned into three groups at 28 days (±3 days) before their expected calving date. The stocking densities of the groups, relative to the standard cubicle and feed bunk number, were i) 80% (13 cows), ii) 100% (16 cows), and iii) 120% (19 cows). Lying and rumination behavior was recorded using electronic data loggers and HR-Tags from d −21 (“d-” means days before calving) until the calving date, d 0. Lying time was assessed to determine the diurnal total hours spent lying per day. Rumination time was averaged in 2 hours interval periods over 24 hours during the experimental period.

Results

Cows in the 80% group spent more time lying and ruminating between d −21 and d −7 and tended to ruminate more between d −14 and d 0. Calcium levels tended to be higher for cows in the 80% group, no other observable differences were found in monitored blood parameters. Moreover, 3.5% fat corrected milk and energy corrected milk yields were higher in 80% group in the first month of lactation. No other observable differences were found in the yield and composition of colostrum and milk in the first 10 months of lactation. The growth and performance of calves in the first week of life was not affected by stocking density of the dams.

Conclusion

We concluded that lower stocking density may increase lying and ruminating behavior of prepartum Holstein cows. However, this did not translate into improved productivity and metabolism.

Behavioral changes associated with fever in transition dairy cows

Dairy cows are often diagnosed with fever without showing clinical symptoms of disease. The aim of this study was to investigate changes in feeding, social, and lying behaviors of cows with fever but without clinical disease, as compared with healthy cows. After parturition, dairy cows of mixed parities were housed in a dynamic group of 20. In the freestall pen, cows had access to 12 electronic feed bins, 2 electronic water bins, and 24 lying stalls. Feeding and social behaviors were recorded using the electronic feed bins, and lying behaviors were measured using electronic data loggers attached to the cow. Rectal body temperature was assessed on a daily basis, and fever defined as a body temperature >39.5°C. All cows were examined for metritis every third day after calving, and all other diseases (e.g., mastitis, ketosis) were diagnosed as per farm protocol. Cows with multiple days of fever (n = 8) and cows with 1 d of fever (n = 18) that were not diagnosed with a clinical disease were compared with a matched sample of healthy cows (i.e., cows that were not clinically ill and never had a fever recorded) of the same parity (categorized as primiparous vs. multiparous). Feeding, social, and lying behaviors were compared for the first 2 d of fever in cows with multiple days of fever, and the day of fever in cows with 1 d of fever. Cows of both fever groups spent less time feeding compared with controls (135 vs. 181 ± 7.6 min/d for multiple fever days, and 158 vs. 185 ± 9.7 min/d for 1 d of fever). Cows with 1 d of fever ate at a faster rate (109 vs. 91 ± 5 g/min) and had a lower number of replacements at the feed bunk (actor replacements: 9.7 vs. 14.6 ± 1.7 no./d; reactor replacements: 11.1 vs. 15.9 ± 1.6 no./d) compared with healthy controls. Overall, cows with fever showed behavioral changes such as decreased feeding time that are consistent with sickness responses described in other species.

Predicting Disease in Transition Dairy Cattle Based on Behaviors Measured Before Calving

Simple Summary

Dairy cattle often become ill after calving. We developed models designed to predict which cows are likely to become ill based upon measures of the cows’ feeding and competitive behaviors before calving. Our models had high sensitivity (73–71%), specificity (80–84%), positive predictive values (73–77%), and negative predictive values (80–80%) for both cows that had previously calved and for those calving for the first time. We conclude that behaviors at the feed bunk before calving can predict cows at risk of becoming sick in the weeks after calving.

Abstract

Dairy cattle are particularly susceptible to metritis, hyperketonemia (HYK), and mastitis in the weeks after calving. These high-prevalence transition diseases adversely affect animal welfare, milk production, and profitability. Our aim was to use prepartum behavior to predict which cows have an increased risk of developing these conditions after calving. The behavior of 213 multiparous and 105 primiparous Holsteins was recorded for approximately three weeks before calving by an electronic feeding system. Cows were also monitored for signs of metritis, HYK, and mastitis in the weeks after calving. The data were split using a stratified random method: we used 70% of our data (hereafter referred to as the “training” dataset) to develop the model and the remaining 30% of data (i.e., the “test” dataset) to assess the model’s predictive ability. Separate models were developed for primiparous and multiparous animals. The area under the receiver operating characteristic (ROC) curve using the test dataset for multiparous cows was 0.83, sensitivity and specificity were 73% and 80%, positive predictive value (PPV) was 73%, and negative predictive value (NPV) was 80%. The area under the ROC curve using the test dataset for primiparous cows was 0.86, sensitivity and specificity were 71% and 84%, PPV was 77%, and NPV was 80%. We conclude that prepartum behavior can be used to predict cows at risk of metritis, HYK, and mastitis after calving.

Competition Strategies of Metritic and Healthy Transition Cows

Simple Summary

Competition for feed is a social stressor for dairy cows and is associated with an increased risk of illness. We investigated how cows trade off the motivation to feed together with group mates against the risk of competitive interactions at the feeder, and in this way identified each individual’s competition strategy. We then related these strategies to cow health. Competition strategies varied between cows and showed low to moderate stability over time. Strategies of metritic and healthy cows did not differ before or after calving, but metritic cows changed strategies more upon entering the social group after calving, particularly in the days before diagnosis. We conclude that cows show individual competition strategies, and that automated measures of strategy change may help in detecting metritis.

Abstract

Our study aimed to characterize social competition strategies in transition cows, and determine how these varied with health status. We retrospectively followed 52 cows during 3 periods (PRE: d −6 to −1 prepartum, POST1: d 1 to 3 postpartum, POST2: d 4 to 6 postpartum). Cows diagnosed with metritis on d 6 postpartum (n = 26) were match paired with healthy cows (n = 26). Measures of agonistic behavior (i.e., replacements at the feeder) and feeding synchrony were determined by an algorithm based on electronic feed bin data, and used to calculate competition strategies via principal component analysis. We found consistent strategies, defined by two components (asynchrony and competitiveness; explaining 82% of the total variance). We observed no differences in strategies when comparing healthy and metritic cows, but metritic cows tended to change their strategies more between PRE and POST1, and between POST1 and POST2, indicating that strategies change in association with parturition and metritis. We conclude that cows show individual variation in competition strategies, and that automated measures of strategy change may help in detecting metritis.

Calving location preference and changes in lying and exploratory behavior of preparturient dairy cattle with access to pasture

The objectives of this study were to (1) describe the calving location of dairy cattle given access to a pasture and barn; (2) identify factors associated with calving location; and (3) compare the lying and exploratory behavior of cows in the 24 h before calving and a previous day. Seventy-two Holstein dairy heifers and cows (n = 36 nulliparous and n = 36 primiparous and multiparous combined) were housed in a covered bedded-pack barn (167.4 m²) with free access to 2.1 ha of pasture. The composition of the group was dynamic, because cows were moved in weekly at 19 ± 6 d [mean ± standard deviation (SD)] before their calving date, and were removed immediately after calving. To facilitate data collection, we divided the environment into 9 sections, including the barn (section 1; 167.4 m²), 7 sections of open pasture (sections 2 to 8; 2,402 ± 60 m²), and 1 section of pasture surrounded by natural forage cover (section 9; 3,593 m²). We then collapsed these 9 sections into 3 distinct areas for further analysis: the barn, open pasture, and natural forage cover. Animals were fitted with accelerometers to measure lying time, lying bout duration, lying bouts, and steps for the 24 h before calving (calving day) and a similar 24 h period 4 to 11 d (median = 7) before calving (baseline day). We included parity (nulliparous vs. primiparous and multiparous) and heat stress [no heat stress = temperature-humidity index (THI) ≤68 vs. heat stress = THI >68 and ≤79] in all analyses; we included time of day and group composition as additional factors that may have affected calving location. We determined exploratory behavior using 10 min instantaneous scan sampling collected from video. At each scan, we recorded the section (1 to 9) the cow or heifer was located in, and then calculated the minimum number of sections that could be crossed between successive scans. Of the total sample, 39% calved in the barn, 26% calved in the open pasture, and 35% calved in the area with natural forage cover. Nulliparous heifers and those calving when heat stress was low (THI ≤68) selected the area with natural forage cover more frequently than the barn. On the calving day, cows spent more time lying down with more short bouts of lying, and crossed more sections compared with the baseline day. Steps were affected by an interactive effect of day, parity, and heat stress; nulliparous heifers took more steps on the calving day during conditions of heat stress compared with no heat stress. Results indicate that cows and heifers had different preferences for their environment at calving, and when provided access to pasture, both changed their lying and exploratory behavior on the day of calving compared with a previous day.

Hot weather increases competition between dairy cows at the drinker

Heat-stressed dairy cows on pasture will compete for resources that aid cooling, but it is not known how heat stress affects the competition for water by indoor-housed cows. The aim of this observational study was to evaluate how heat stress affects the behavior of indoor-housed cows at the drinker at both group and cow levels. For 3 wk after calving, cows were housed in a dynamic group of 20 animals in a pen with 12 electronic feed bins, 2 electronic water bins, and 24 freestalls. A total of 69 lactating Holstein dairy cows were enrolled over the 59-d study. The electronic water bins recorded time spent at the drinker, frequency of visits, water intake, and competitive events for 24 h/d. Competitive events were quantified using the number of replacements (recorded when there was a ≤29-s interval between 2 cows sequentially visiting the same drinker). The number of replacements a cow was involved in was used to determine her level of competitive success at the drinker (low, medium, high). The temperature-humidity index (THI) was recorded by the local weather station, and moving averages for daily maximum THI over a 3-d period were calculated. For the analysis of time spent at the drinker, frequency of visits, and water intake, the measures from all cows were averaged to create 1 observation per day, and the number of replacements at the drinker was summed. A linear regression was performed to determine the relationship between THI and group-level drinking behavior. At the cow level, a repeated measures mixed model, with fixed effects of level of competitive success, milk yield, and 3-d maximum THI and a first-order autoregressive covariance structure, was used to determine how increasing THI affects the drinking behavior of individual cows based on their level of competitive success. Feed intake was included as a fixed effect in the water intake model. We found that, with increasing THI, cows drank more water, spent more time at the drinker, made more visits to the drinker, and engaged in more competitive events at the drinker. In exploratory analysis, we found that cows with low competitive success at the drinker shifted their drinking behavior to avoid the drinker at the hottest and most competitive time of day. These results indicate that behavior can be used to indicate when cows feel hot. These measures may be of practical value in deciding when to provide cooling, especially for farms where attendance at the drinker can be monitored electronically.

Effect of weather on activity and lying behaviour in clinically healthy grazing dairy cows during the transition period

Lying behaviour and activity were measured in healthy grazing dairy cows during the transition from late gestation to early lactation (i.e. the transition period). Behaviour data derived from IceTag® or IceQube® (IceRobotics, Edinburgh, Scotland, UK) tri-axial accelerometers were collated from 311 cow parities of mixed age and breed (Holstein–Friesian, Jersey and crossbred Holstein–Friesian × Jersey) cows from four experiments. The IceTag and IceQube devices captured lying and step data at 1- and 15-min intervals respectively. Behaviour was recorded during the transition period (Day –21 prepartum to Day 34 postpartum) to determine daily lying time, number of lying bouts (LB), mean LB duration and number of steps. The effect of rainfall and air temperature on lying behaviour and activity during two periods, namely, prepartum (Day –21 to Day –3) and postpartum (Days 3–34) was evaluated. Multiple-regression analysis determined that decreased air temperature and increased rainfall is associated with a decline in daily lying time, number of LB and LB duration during both prepartum and postpartum periods. Exposure to both wet and cold conditions exacerbated the behavioural response. The results highlighted the importance of considering the effects of air temperature and rainfall and the interaction of these two climate variables when analysing lying behaviour and activity. Further work is required to quantify the trigger points for this activity modulation, to help understand the balance of welfare experiences in the life of a grazing cow.

Effects of Body Condition Score Changes During Peripartum on the Postpartum Health and Production Performance of Primiparous Dairy Cows

Simple Summary

This study systematically describes the effects of body condition score (BCS) changes in primiparous cows during the peripartum period on hormone indexes, health, and production. The BCS and its changes indirectly measure the degree of fat mobilization and is a good predictor of the risk of postpartum disease. In production practice, confounding the management of primiparous and multiparous cow risks neglecting the postpartum characteristics of primiparous cows. A prospective observational study observed that primiparous cows that have a lower BCS have higher non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHBA) concentrations and more dramatic hormonal changes. Prepartum BCS changes were inconsistent and small, while after calving, there was a drastic decline in the BCS, suggesting that even a slight drop in the prepartum BCS may be a warning of a postpartum risk for primiparous cows. It is suggested that operators attach importance to the primiparous cow prepartum BCS and keep it stable through prepartum management adjustments, since an ideal BCS at calving reduces the incidence of postpartum disease.

Abstract

This is a prospective observational study that evaluates the effects of body condition score (BCS) changes in primiparous Holstein cows during peripartum on their NEFA and BHBA concentrations, hormone levels, postpartum health, and production performance. The cows under study (n = 213) were assessed to determine their BCS (5-point scale; 0.25-point increment) once a week during the whole peripartum by the same researchers; backfat was used for corrections. Blood samples were collected 21 and 7 days before calving and 7, 21, and 35 days after calving, and were assayed for NEFA, BHBA, growth hormone (GH), insulin, leptin, and adiponectin concentrations. The incidence of disease and milk yield were recorded until 84 days after calving. Cows were classified according to their BCS changes during peripartum as follows: Those that gained BCS (G; ΔBCS ≥ 0.25), maintained BCS (M; ΔBCS = 0–0.25), or lost BCS (L; ΔBCS ≥ 0.5). The BCS at −21 days and at 7, 14, and 21 days were different (p < 0.01), but trended toward uniformity in all groups at calving. The L group had higher NEFA and BHBA concentrations and hormone levels (p < 0.01) than the M and G groups at 21 and 35 days after calving, and had a higher incidence of uterine and metabolic diseases; however, there were no differences in production performance between the various groups. In conclusion, a lower BCS in primiparous cows during peripartum influences the NEFA and BHBA concentrations, hormone levels, and occurrence of health problems postpartum. The postpartum effects of BCS changes appear prior to calving.

Repeatability of traits for characterizing feed intake patterns in dairy goats: a basis for phenotyping in the precision farming context

In ruminants, feeding behaviour variables are parameters involved in feed efficiency that show variation among individuals. This study aimed to evaluate during the first two production cycles in ruminants the repeatability of feed intake pattern, which is an important aspect of feeding behaviour. Thirty-five dairy goats from Alpine or Saanen breeds were housed in individual pens at four periods (end of first gestation, middle of first and second lactations and middle of second gestation which is also the end of first lactation) and fed a total mixed ration (TMR) ad libitum. Individual cumulative dry matter intake (DMI) was automatically measured every 2 min during the last 4 days of each period. Feed intake pattern was characterized by several measures related to the quantity of feed eaten or to the rate of intake during the 15 h following the afternoon feed delivery. Two main methods were used: modelling cumulative DMI evolution by an exponential model or by a segmentation-clustering method. The goat ability to sort against dietary fibre was also evaluated. There was a very good repeatability of the aggregate measures between days within a period for a given goat estimated by the day effect within breed and goat, tested on the residual variance (P > 0.95). The correlations between periods were the highest between the second and either the third or fourth periods. With increasing age, goats sorted more against the fibrous part of the TMR and increased their initial rate of intake. Alpine goats ate more slowly than Saanen goats but ate during a longer duration. Principal component analysis (PCA) was performed on all the aggregate measures of feed intake patterns. The factor score plots generated by the PCA highlighted the opposition between the different measures of feed intake patterns and the sorting behaviour. The projection of the animals on the scoring plots showed a breed effect and that there was a continuum for the feed intake pattern of goats. In conclusion, this study showed that the feed intake pattern was highly repeatable for an animal in a given period and between periods. This means that phenotyping goats in a younger age might be of interest, either to select them on feeding behaviour and choose preferentially the slow eaters or to adapt the quantity offered and restrict feed delivery to the fast eaters in order to increase feed efficiency and welfare by limiting the occurrence of acidosis, for example.