Temporal associations between low body condition, lameness and milk yield in a UK dairy herd

Risk of Lameness in Dairy Cows with Paratuberculosis Infection

Simple Summary

Johne’s disease (JD) is an important disease affecting cows in the UK dairy industry, as is lameness, and both cause milk production losses and cows losing weight. The aim of this work was to see if cows with JD were more likely to be lame and if so, what the order of occurrence of these two events is. We looked at the JD and lameness records of two farms and paired 98 JD cows (half of them with a high response to the test for JD) and compared them with herd mates. We evaluated the timing and the proportion of lameness in JD-positive cows compared to their controls and proportion of lameness before and after the first JD-positive test. JD cows turn lame on average three months earlier and are lame 2.7 times more often than non-JD cows. Further, high positive cows were 2.8 times more likely to develop lameness after JD diagnosis compared to medium positive cows. Results of this study suggest that there is a link between JD and lameness and that JD precedes lameness. The underlying mechanisms for this association remain unknown and were not the scope of this study.

Abstract

Johne’s disease (JD) is an important disease affecting the UK dairy industry, as is cattle lameness. An association between JD and lameness has been suggested; however, little evidence exists to support this. The purpose of this study was to determine if cows affected by JD were more likely to be lame and if so, what the temporal association is. Retrospective dairy cow mobility and JD status (based on milk ELISA) data were obtained from two farms of 98 JD cows (49 high and 49 medium positive) and their matched controls. We evaluated the timing and the proportion of (chronic) lameness in JD-positive cows versus controls and proportion of lameness before and after the first ELISA positive test. Compared to their controls, JD cows are lame more often (Odds Ratio = 2.7 (95% Confidence Interval = 1.2–6.0) p = 0.017) and became lame on average three months earlier (p = 0.010). High positive cows were more likely to develop lameness after seroconversion (OR = 2.8 (95% CI = 1.1–7.5), p = 0.038) versus medium positive cows. Results of this study suggest that there is a link between JD and lameness and that JD precedes lameness. The underlying mechanisms for this association remain unknown and were not the scope of this study.

Dairy Farmers' Perceptions of and Actions in Relation to Lameness Management

Simple Summary

Lameness is a pressing issue in dairy production. Dairy farmers are primarily responsible for the welfare of their cows and decision-making regarding lameness management. However, there are concerns regarding the communication of the importance of lameness to farmers and their motivation towards proper management. A review of the literature indicates that various factors influence farmers’ perceptions about lameness, their adoption of recommended measures and whether or not they end up treating a lame cow. This review summarizes these related issues in consideration of the welfare and economic implications of farmers’ decisions. The information herein is vital to the identification of measures on how to motivate dairy farmers towards appropriate lameness management.

Abstract

Lameness continues to be a welfare and economic issue for dairy cows. However, the consequences of lameness seem to be better understood by veterinarians and related personnel in comparison to dairy farmers. Prompt detection and treatment of lame cows is essential in reducing its negative impact on milk processing systems. To that end, understanding farmers’ perceptions regarding the significance of lameness to dairy cows is vital. One fundamental aspect is the underestimation of lameness prevalence by dairy farmers, which is as a result of different understanding of the problem. The same applies to their decision to treat lame cows and to adopt various detection and management practices. All of these shortcomings contribute to poor cattle welfare and economic losses in dairy production. This review summarizes the results of studies that have investigated dairy farmers’ perceptions of lameness and the associated implications on the wellbeing and productivity of dairy cows. Factors associated with farmers’ attitudes toward claw health and lameness management are also presented. Additionally, economic observations relating to lameness prevention, treatment and the adoption of lameness detection systems are also highlighted. To strengthen these points, interventional programmes requiring farmers’ participation are discussed as a promising approach in answering some of these challenges. A review of the literature indicates both the opportunities and barriers inherent in the tackling the lameness issue from the farmers’ perspectives. Such knowledge is crucial in identifying measures on how to motivate dairy farmers towards proper lameness management.

Routine Herd Health Data as Cow-Based Risk Factors Associated with Lameness in Pasture-Based, Spring Calving Irish Dairy Cows

Simple Summary

Dairy cow lameness is considered one of the most important animal welfare and economic concerns for the dairy industry. Cow-based risk factors for lameness are not well described, especially in comparison to herd-level risk factors such as housing environment and roadway condition. This study investigates the use of routinely gathered herd health data as cow-based risk factors for lameness in dairy cows. A total of 1715 cows in 10 pasture-based Irish dairy herds were monitored for lameness during the spring and summer of 2013 and 2014 as part of the University College Dublin herd health programme. Herd health monitoring data analysed to identify potential risk factors for lameness consisted of milk production data, genetic merit information, calving details, peri-parturient disease records and body condition scores. This analysis showed a significant effect of increasing parity, lower body condition score at calving and excessive body condition loss after calving on the risk of cows being diagnosed as lame during the lactation. In conclusion, routinely gathered herd health monitoring data can be used to identify cows at increased risk of being lame and to implement lameness control strategies.

Abstract

Herd-level risk factors related to the cow’s environment have been associated with lameness. Uncomfortable stall surface and inadequate depth of bedding as well as abrasive alley way surface are contributing factors to increased levels of lameness. Access to pasture has been found as having a beneficial effect on cows’ locomotion. However, dairy cattle managed under grazing conditions are exposed to a different set of risk factors for lameness, mainly associated with cow tracks. Cow-based risk factors for lameness are not as clearly defined as the herd level risk factors. The objective of the present study was to use routine herd health monitoring data to identify cow-based risk factors for lameness and utilise this information to indicate cows at risk of developing lameness in the first 150 days of lactation. Lameness data were gathered from 10 pasture-based dairy herds. A total of 1715 cows were monitored, of which 1675 cows were available for analysis. Associations between lameness status and potential cow-level risk factors were determined using multivariable logistic regression. Parity 3 and 4 + cows showed odd ratios (OR’s) for lameness of 3.92 and 8.60 respectively (95% confidence interval (CI) 2.46–6.24; 5.68–13.0). Maximum loss of Body condition score (BCS) after calving exhibits OR’s for lameness of 1.49 (95% CI 1.08–2.04) if cows lost 0.5 in BCS after calving and 2.26 (95% CI 1.30–3.95) for cows losing more than 0.5 BCS. Animals calving in BCS 3.25 and ≥ 3.5 had correlating OR’s of 0.54 (95% CI 0.34–0.87) and 0.33 (95% CI 0.16–0.65) for being lame compared to cows calving with BCS ≤ 2.75. Data gathered as part of herd health monitoring can be used in conjunction with lameness records to identify shortcomings in lameness management. Findings and recommendations on lameness management can be formulated from readily available information on cow-based risk factors for lameness.

Prevalence of lameness and associated risk factors on dairy farms in the Maritime Provinces of Canada

Lameness in dairy cattle is a major issue for the industry due to the effects on the welfare of the animal, the economic impact, and consumer perception. The aim of this study was to determine the prevalence of lameness and explore potential risk factors in the Maritime Provinces of Canada. Cows were scored for lameness and potential risk factors and were assessed in 46 freestall herds and 33 tiestall herds in Nova Scotia, New Brunswick, and Prince Edward Island. In freestall herds, lameness was assessed using the most common method, locomotion scoring. A cow with a gait score of ≥3 out of 5 was considered to be lame. In tiestall herds, lameness was assessed using an alternative method known as stall lameness scoring. This assessment consisted of observation of the cow for 4 behavioral changes: standing on the edge of the stall, shifting weight, resting a limb, and uneven weight bearing when moved side to side. A cow displaying 2 or more of these behaviors was considered to be lame. At the time of the assessment, other animal-, environmental-, and management-based measurements were collected. These measurements were used in multivariable logistic regression analysis to determine risk factors that were associated with lameness for both freestalls and tiestalls independently. The prevalence of lameness was 21% for freestall-housed cattle and 15% for tiestall-housed cattle. Of the 1,488 tiestall-housed cows that were assessed, 68% showed no behavioral changes, whereas 15, 15, 2, and <1% showed 1, 2, 3, or 4 changes, respectively. In freestalls, higher odds of lameness were seen when cows spent ≥3 h/d in the holding area for milking compared with those that spent <3 h/d. In tiestall herds, higher odds of lameness were seen when bedding material was wet compared with when it was dry. For both lactating cow facility types, housing the dry cows and heifers on a deep bedded pack compared with tiestalls or freestalls was associated with a decreased odds of lameness. There were also many cow-level variables associated with lameness, including parity, daily milk production, stage of production, body condition, and width at the tuber coxae (hook bones). If producers become aware of the risk factors associated with lameness, they can make informed decisions on where to implement changes to help reduce the level of lameness in their herd.

Aspects of lameness in pasture based dairy systems

Pasture-based dairy systems are implemented all over the world. Access to pasture is perceived to be advantageous for animal welfare in western societies. However, the benefits of grazing on lameness are not uniformly verifiable. This is related to the challenges that grazing cows face which are different from zero-grazing systems to some extent, but may nevertheless be deleterious. The distribution of lesion types comparing housed and pastured cattle differs between studies. This may be caused by differences in how strongly certain risk factors apply in these studies. Major risk factors for lameness in grazing cattle are related to the risk of trauma, for example from long walking distances and lack of track maintenance, and cow factors such as the adaptability of certain breeds to the grazing lifestyle. The consequences of lameness are similar to zero-grazing cattle and negatively affect animal welfare and productivity.

Risk Factors for Deterioration of the Clinical Condition of Cull Dairy Cows During Transport to Slaughter

Cull dairy cows are typically transported to slaughter by road. Across different types of cattle, road transport is recognized as stressful. Cull dairy cows may have different injuries or weaknesses and may thus be more vulnerable to transport stress than other types of cattle. The aim of this study was to investigate whether the clinical condition of cull dairy cows deteriorates during transport (< 8 h), and to evaluate risk factors for potential deterioration of the clinical condition. A total of 411 dairy cows were clinically examined on farm before loading and again after unloading at the slaughter plant. The clinical examination included locomotion, presence of wounds, milk leakage, and general condition. One-fifth of the cows either became lame or more lame during transport, and there was a significant increase in the proportion of lame cows after transport (41% after vs. 31% before, P < 0.0001). A significant increase in the proportion of cows with milk leakage (17% vs. 1%, P < 0.0001) and wounds (34% after vs. 22% before, P < 0.0001) after transport were also found. Low body condition score (BCS) (< 2.75) (P = 0.001), early or late lactation [< 100 days in milk (DIM) or >300 DIM] (P = 0.01), digital dermatitis in the hind feet (P = 0.01), and pelvic asymmetry (P = 0.001) were identified as risk factors for the deterioration in lameness during transport. Early lactation (< 100 DIM) (P = 0.04) and transport distance (>100 km) (P = 0.006) were identified as risk factors for milk leakage. For wounds, no significant risk factors were found. The results demonstrate that cull dairy cows are vulnerable to the strains of transport, even journeys shorter than 8 h, to the extent that the occurrence of clinical findings were increased after transport in cows legally considered fit for transport. These results call for further research into the animal welfare implications and optimization of cattle transport.

Claw horn lesions in mid-lactation primiparous dairy cows under pasture-based systems: Association with behavioral and metabolic changes around calving

The objectives of this study were to describe the lying behavior of primiparous dairy cows under pasture-based systems during the pre- and postcalving period and characterize the association of lying behavior and analytes related to energy metabolism during this period with claw horn disruption lesion development later in lactation. Our convenience sample included 39 primiparous Holstein cows from 3 commercial farms that were assessed for body condition score (BCS; 5-point scale, 0.25-point increments) and had blood collected at wk -3, -2, -1, 1, 2, and 3 relative to calving date. Blood samples were assayed for nonesterified fatty acids, β-hydroxybutyrate (BHB), and cholesterol concentrations. Electronic data loggers (HOBO Pendant G Acceleration, Onset Computer Corporation, Bourne, MA) recorded lying behavior at 1-min intervals from 3 wk before calving to 3 wk after calving. Starting at 4 wk after calving and until 16 wk after calving, cows were examined for claw lesions at approximately 4-wk intervals. Sole lesions and white line lesions were scored on a 0 to 10 scale. Of the 39 primiparous cows, 19 cows scored 0 at all exams during the entire study period and 20 cows had at least 1 severe lesion (score ≥4) between 8 and 16 wk after calving. Time spent lying before calving averaged 10.3 ± 0.3 h/d, but declined to 7.3 ± 0.3 h/d after calving (least squares means ± standard error). At calving, we noted an increase in the number of lying bouts (12.9 ± 0.45 bouts/d) compared with the pre- and postcalving averages of 11.6 (±0.53) and 9.1 (±0.47) bouts, respectively. Cows that developed claw lesions later in mid lactation spent less time lying down than cows without lesions during wk 3 after calving compared with healthy cows (7.29 ± 0.22 vs. 8.51 ± 0.16 h/d). Lesion cows had fewer lying bouts per day, and these bouts were of longer duration than no-lesion cows after calving. Increased odds of lesion were found to be associated with shorter lying times and fewer number of lying bouts during wk 3 (odds ratio = 1.23). Nonesterified fatty acids (747 ± 58 vs. 990 ± 86.85 µmol/L) and BHB (0.77 ± 0.06 vs. 0.60 ± 0.04 mmol/L) concentrations during wk 1 were greater in cows that developed claw lesions relative to cows that did not develop lesions. The BHB concentrations also remained higher in wk 2 for cows that developed claw lesions (0.63 ± 0.04 vs. 0.46 ± 0.03 mmol/L) compared with cows that did not develop any lesions. Cows that developed lesions experienced greater losses in BCS from wk -3 to 3 than cows without lesions (0.74 ± 0.01 and 0.61 ± 0.01 BCS change, respectively). In summary, changes in lying behavior and energy metabolic status after calving were associated with claw horn disruption lesions in mid-lactation primiparous cows under pasture-based systems.

Frequency and distribution of foot lesions identified during cattle hoof trimming in the Province of Antioquia, Colombia (2011-2016)

Lameness is a severe welfare problem in cattle and has a detrimental effect on longevity, productivity, and reproductive performance. This study aimed to describe the frequency and distribution of foot lesions in cattle using hoof trimming records over a period of 6 years in the Province of Antioquia (Colombia). The data collection instrument enabled differentiation between limbs, digits, and views. The Claw Lesion Identification in Dairy Cattle brochure was the reference for foot lesion identification. A total of 1814 foot lesions observations, recorded from 1120 cows in 71 herds, were analyzed and 11 different foot lesions were identified. Non-infectious foot lesions were more common than infectious (94.4 vs 5.6%). White line disease was more frequently observed in the hind limbs (79.6%) compared to the front limbs (20.4%), and more frequent in medial claws of the front limbs (70.3%) compared to lateral claws (29.7%). In hind limbs, the lateral claws were more commonly affected (65.7%) compared to the medial claws (34.3%). Claw zone 3 was affected in 61.3% of the cases, followed by zones 2 (21.7%) and 1 (17%). Although our data are from a limited area of the country, they are consistent with published and anecdotal reports of foot lesions in cattle in Colombia and worldwide. Our results suggest that there is need for additional prospective research under Colombian dairy cattle management conditions to better understand the lameness and benefit of trimming intervention.

Automated monitoring of dairy cow body condition, mobility and weight using a single 3D video capture device

Here we propose a low-cost automated system for the unobtrusive and continuous welfare monitoring of dairy cattle on the farm. We argue that effective and regular monitoring of multiple condition traits is not currently practicable and go on to propose 3D imaging technology able to acquire differing forms of related animal condition data (body condition, lameness and weight), concurrently using a single device. Results obtained under farm conditions in continuous operation are shown to be comparable or better than manual scoring of the herd. We also consider inherent limitations of using scoring and argue that sensitivity to relative change over successive observations offers greater benefit than the use of what may be considered abstract and arbitrary scoring systems.

Control of helminth ruminant infections by 2030

Helminth infections have large negative impacts on production efficiency in ruminant farming systems worldwide, and their effective management is essential if livestock production is to increase to meet future human needs for dietary protein. The control of helminths relies heavily on routine use of chemotherapeutics, but this approach is unsustainable as resistance to anthelmintic drugs is widespread and increasing. At the same time, infection patterns are being altered by changes in climate, land-use and farming practices. Future farms will need to adopt more efficient, robust and sustainable control methods, integrating ongoing scientific advances. Here, we present a vision of helminth control in farmed ruminants by 2030, bringing to bear progress in: (1) diagnostic tools, (2) innovative control approaches based on vaccines and selective breeding, (3) anthelmintics, by sustainable use of existing products and potentially new compounds, and (4) rational integration of future control practices. In this review, we identify the technical advances that we believe will place new tools in the hands of animal health decision makers in 2030, to enhance their options for control and allow them to achieve a more integrated and sustainable approach to helminth control in support of animal welfare and production.

Cow- and herd-level factors associated with lameness in small-scale grazing dairy herds in Brazil

This cross-sectional study aimed to assess lameness occurrence and to identify the associated risk factors in small-scale grazing dairy herds. Forty four farms (mean lactating herd size was 42 cows, SD = 11.2, range: 28-74) located in the south of Brazil were visited twice, approximately 4 months apart, in 2015. Locomotion was scored in 1633 and 1836 cows at the first and second visit, respectively. Potential risk factors for lameness were assessed through inspection of cows and facilities, and a questionnaire for farmers about herd management practices. Multilevel logistic regressions, using herd as random effect, were fitted to investigate the cow-level risk factors for accumulated incident (not lame at the first visit but lame on the second), chronic (lame on both visits) and recovered (lame at the first visit but sound on the second) cases of lameness. A multilevel linear regression, using municipality as a random effect, was fitted for herd-level analysis. Cumulative lameness incidence between two visits (1110 cows in 41 herds) was 29.6% (range: 0-80); lameness prevalence (n = 44 herds) was 31% (10-70) and 35% (5-76) at the first and second visits, respectively. The odds of incident cases were greater in Holstein cows [odds ratio (OR) = 4.0, 95% confidence interval 2.1-7.6] compared with Jerseys, in cows in parities 2-3 (OR 2.5, 1.4-4.4) or >3 (OR 6.6, 3.3-13.1) relative to parity 1, in cows having a low body condition score (BCS) of 2-2.75 or 3 on the first visit (OR 2, 1.1-3.7), and in cows with observed hoof abnormalities (OR 2.5, 1.3-4.7). Similar associations were found for chronic cases, with Holstein and crossbred cows having greater odds of lameness, compared to Jersey, and chronic cases being more likely in cows with increasing parity, with BCS at first visit of 2-2.75, and with presence of hoof abnormalities. Jersey or crossbred cows (OR 3.2, 1.3-8.1) and cows in parity 1-2 (OR 3.6, 1.6-8.4) had higher probability of recovery from lameness. Having a herd composed of Holstein cows was associated with 13.5% (CI 4.3-22.8) greater incidence of lameness (n = 35). For every 1 km/h increase in the average speed of movement of the herd to or from milking, lameness incidence increased by 5% (CI 0.1-10). Given that the occurrence of lameness was high there is great opportunity to reduce lameness in this population. This study highlights some management and prevention practices that may reduce lameness in these grazing herds.

The contribution of previous lameness events and body condition score to the occurrence of lameness in dairy herds: A study of 2 herds

It has been demonstrated that low body condition and previous occurrence of lameness increase the risk of future lameness in dairy cows. To date the population attributable fraction (PAF), which provides an estimate of the contribution that a risk factor makes toward the total number of disease events in a population, has not been explored for lameness using longitudinal data with repeated measures. Estimation of PAF helps to identify control measures that could lead to the largest improvements on-farm. The aim of this study was to use longitudinal data to evaluate the proportion of lameness that could be avoided in 2 separate herds (2 populations) through (1) reduced recurrence of previous lameness events, (2) and moving body condition score (BCS) into more optimal ranges. Data were obtained from 2 UK dairy herds: herd A, a 200-cow herd with 8 yr of data from a total of 724 cows where lameness events were based on weekly locomotion scores (LS; 1 to 5 scale), and herd B, a 600-cow herd with data recorded over 44 mo from a total of 1,040 cows where treatment of clinical cases was used to identify lameness events. The PAF for categories of BCS were estimated using a closed equation appropriate for multiple exposure categories. Simulation models were used to explore theoretical scenarios to reflect changes in BCS and recurrence of previous lameness events in each herd. For herd A, 21.5% of the total risk periods (cow-weeks) contained a lameness event (LS 3, 4, or 5), 96% of which were repeat events and 19% were recorded with BCS <2 (3 wk previously; 0 to 5 scale). When lameness events were based on 2 consecutive weeks of LS 4 or 5, 4% of risk periods were recorded as lame, of which 89.5% were repeat events. For herd B, 16.3% of the total risk periods (consecutive 30 d) contained a lameness event (72.6% were repeat events) and 20% were recorded with BCS ≤2 (0 to 120 d previously). The median PAF for all previous lameness was between 79 and 83% in the 2 herds. Between 9 and 21% of lameness events could be attributed to previous lameness occurring >16 wk before a risk period. The median PAF estimated for changes in BCS were in the region of 4 to 11%, depending on severity of lameness. Repeated bouts of lameness made a very large contribution to the total number of lameness events. This could either be because certain cows are initially susceptible and remain susceptible, due to the increased risk associated with previous lameness events, or due to interactions with environmental factors. This area requires further research.

Farm-specific economic value of automatic lameness detection systems in dairy cattle: From concepts to operational simulations

Although prototypes of automatic lameness detection systems for dairy cattle exist, information about their economic value is lacking. In this paper, a conceptual and operational framework for simulating the farm-specific economic value of automatic lameness detection systems was developed and tested on 4 system types: walkover pressure plates, walkover pressure mats, camera systems, and accelerometers. The conceptual framework maps essential factors that determine economic value (e.g., lameness prevalence, incidence and duration, lameness costs, detection performance, and their relationships). The operational simulation model links treatment costs and avoided losses with detection results and farm-specific information, such as herd size and lameness status. Results show that detection performance, herd size, discount rate, and system lifespan have a large influence on economic value. In addition, lameness prevalence influences the economic value, stressing the importance of an adequate prior estimation of the on-farm prevalence. The simulations provide first estimates for the upper limits for purchase prices of automatic detection systems. The framework allowed for identification of knowledge gaps obstructing more accurate economic value estimation. These include insights in cost reductions due to early detection and treatment, and links between specific lameness causes and their related losses. Because this model provides insight in the trade-offs between automatic detection systems' performance and investment price, it is a valuable tool to guide future research and developments.

Association between Lameness and Indicators of Dairy Cow Welfare Based on Locomotion Scoring, Body and Hock Condition, Leg Hygiene and Lying Behavior

Simple Summary

Lameness is a major welfare issue in dairy cows. Locomotion scoring (LS) is mostly used in identifying lame cows based on gait and postural changes. However, lameness shares some important associations with body condition, hock condition, leg hygiene and behavioral changes such as lying behavior. These measures are considered animal-based indicators in assessing welfare in dairy cows. This review discusses lameness as a welfare problem, the use of LS, and the relationship with the aforementioned welfare assessment protocols. Such information could be useful in depicting the impact on cow welfare as well as in reducing the occurrence of lameness in dairy herds.

Abstract

Dairy cow welfare is an important consideration for optimal production in the dairy industry. Lameness affects the welfare of dairy herds by limiting productivity. Whilst the application of LS systems helps in identifying lame cows, the technique meets with certain constraints, ranging from the detection of mild gait changes to on-farm practical applications. Recent studies have shown that certain animal-based measures considered in welfare assessment, such as body condition, hock condition and leg hygiene, are associated with lameness in dairy cows. Furthermore, behavioural changes inherent in lame cows, especially the comfort in resting and lying down, have been shown to be vital indicators of cow welfare. Highlighting the relationship between lameness and these welfare indicators could assist in better understanding their role, either as risk factors or as consequences of lameness. Nevertheless, since the conditions predisposing a cow to lameness are multifaceted, it is vital to cite the factors that could influence the on-farm practical application of such welfare indicators in lameness studies. This review begins with the welfare consequences of lameness by comparing normal and abnormal gait as well as the use of LS system in detecting lame cows. Animal-based measures related to cow welfare and links with changes in locomotion as employed in lameness research are discussed. Finally, alterations in lying behaviour are also presented as indicators of lameness with the corresponding welfare implication in lame cows.

Producer estimates of prevalence and perceived importance of lameness in dairy herds with tiestalls, freestalls, and automated milking systems

Lameness is one of the most important welfare and productivity concerns in the dairy industry. Our objectives were to obtain producers' estimates of its prevalence and their perceptions of lameness, and to investigate how producers monitor lameness in tiestall (TS), freestall with milking parlor (FS), and automated milking system (AMS) herds. Forty focal cows per farm in 237 Canadian dairy herds were scored for lameness by trained researchers. On the same day, the producers completed a questionnaire. Mean herd-level prevalence of lameness estimated by producers was 9.0% (±0.9%; ±SE), whereas the researchers observed a mean prevalence of 22.2% (±0.9%). Correlation between producer- and researcher-estimated lameness prevalence was low (r = 0.19) and mean researcher prevalence was 1.6, 1.8, and 4.1 times higher in AMS, FS, and TS farms, respectively. A total of 48% of producers thought lameness was a moderate or major problem in their herds (TS = 34%; AMS =53%; FS = 59%). One third of producers considered lameness the highest ranked health problem they were trying to control, whereas two-thirds of producers (TS = 43%; AMS = 63%; FS = 71%) stated that they had made management changes to deal with lameness in the past 2 yr. Almost all producers (98%) stated they routinely check cows to identify new cases of lameness; however, 40% of producers did not keep records of lameness (AMS = 24%; FS = 23%; TS = 60%). A majority (69%) of producers treated lame cows themselves immediately after detection, whereas 13% relied on hoof-trimmer or veterinarians to plan treatment. Producers are aware of lameness as an issue in dairy herds and almost all monitor lameness as part of their daily routine. However, producers underestimate lameness prevalence, which highlights that lameness detection continues to be difficult in in all housing systems, especially in TS herds. Training to improve detection, record keeping, identification of farm-specific risk factors, and treatment planning for lame cows is likely to help decrease lameness prevalence.

Prevalence of lameness, claw lesions, and associated risk factors in dairy farms in Selangor, Malaysia

The objectives of this cross-sectional study were to estimate the prevalence of lameness, claw lesions, and associated risk factors in dairy farms in Selangor, Malaysia. The sample population was 251 lactating cows from 8 farms assessed for lameness and claw lesions by locomotion scoring and claw assessment respectively while specific animal-based measures were hypothesized as cow-level risk factors. The Wilcoxon rank test and logistic regression were applied to assess the prevalence of lameness, claw lesions, and association with potential risk factors, respectively. The prevalence of lameness was 19.1% ranging from 10.0 to 33.3% while 31.1% of cows had claw lesions and ranged from 16.3–40%. Claw lesions were recorded in 87.5% of the lame cows with highest being those affected with sole lesions (54.2%) and white line disease (61.2%). Overall, the occurrence of overgrown claws, sole lesions, white line disease, and digital dermatitis were 37, 18.2, 10.9, and 8.3%, respectively. More than one claw lesion per cow was present in 71.8% of the affected cows. Lameness was associated with early lactation (OR = 3.3; 95% CI 2–7), injured hocks (OR = 4.8; 95% CI 5-17), and dirty legs hygiene (OR = 2.6; 95% CI 1.3-6.2), whereas presence of claw lesions was associated with dirty legs hygiene (OR = 4.7; 95% CI 4-11) and overgrown claw (OR = 2.7; 95% CI 1.4-5.3). To reduce the prevalence of lameness, farmers need to improve the management of cows with overgrown claw, injured hocks, and cleanliness by establishing routine claw trimming and efficient stall design.

Effect of claw disorders on milk production, fertility, and longevity, and their economic impact in Spanish Holstein cows

The aims of this study were (1) to estimate the phenotypic association between different degrees of severity of claw disorders and production, fertility performance, and longevity in Spanish dairy cattle, and (2) to quantify its economic impact at the animal and herd level. In this study, claw data comprised 108,468 trimmings collected between 2012 and 2014 by 25 trimmers from 804 Holstein dairy herds. The claw disorders considered were the 3 most frequent disorders in Spanish dairy herds: dermatitis (DE), sole ulcer (SU), and white line disease (WL). The presence of SU or WL was associated with a significant decrease in milk production and was more important in cows in second or later lactations. A severe lesion of SU or WL lead to twice the milk losses associated with a mild lesion, ranging from 1.47 to 2.66kg/d of energy-corrected milk. The presence of SU or WL during the early lactation period was associated with more days open, fewer inseminations to get pregnant, and longer calving to first service interval (4.83 and 8.0 d longer due to mild and severe lesions of SU, respectively, and 4.94 and 17.43 d longer due to mild and severe lesions of WL, respectively). The occurrence of a case of SU or WL in first lactation had a significant effect on longevity, with severe lesions reducing up to 71 d of productive life. The cost of a mild lesion ranged from $53 to $232 per affected cow and year, whereas the cost of a severe lesion ranged from $402 to $622 per affected cow and year. The annual costs per cow for DE, SU, and WL were $10.80, $50.9, and $43.2, respectively. An average herd with 64 cows had an extra expenditure of $691/yr due to DE, $3,256/yr due to SU, and $2,765/year due to WL. Milk losses, longer calving intervals, and premature culling contributed to more than half of the costs. Therefore, providing this information to farmers could help decide on strategies to reduce the incidence of claw disorders on the farm.

Claw disorders in dairy cattle - an unexpected association between energy metabolism and sole haemorrhages

The present study investigated whether changes of energy metabolism post-partum (pp) are associated with claw health. For this purpose, back-fat-thickness (BFT) was measured and blood samples were taken from 146 cows at four examination times. The serum levels of free fatty acids (FFA), ß-hydroxybutyrate (BHB) and glucose were measured. Furthermore, in the first week postpartum (pp) and at 8 weeks pp, a claw trimming was done and the presence and extent of sole haemorrhages (SH) was recorded. Animals with high BFT at calving and therefore high fat mobilisation and whose FFA and BHB levels in the first week pp exceeded the reference values had fewer pathological changes of the claws than thinner animals whose FFA and BHB levels stayed within reference ranges. The body condition before calving, represented in this study by BFT, plays an important role in non-infectious claw disorders. Poorer body condition was found to be associated with the SH that develop in the first 2 months of lactation.

Lameness in dairy heifers; impacts of hoof lesions present around first calving on future lameness, milk yield and culling risk

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More severe claw horn lesions were associated with increased risk of future lameness.

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More severe sole lesions were associated with reduction in daily yield of 2.68 kg.

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Managing heifers to reduce severe lesions is likely to have positive herd impacts.

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Mild claw horn lesions associated with reduced risk of future lameness and culling.

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Mild insult may lead to adaptive changes in the hoof which are beneficial.

The importance of lameness in primiparous dairy heifers is increasingly recognised. Although it is accepted that clinical lameness in any lactation increases the risk of future lameness, the impact of foot lesions during the first lactation on long-term lameness risk is less clear. This retrospective cohort study aimed to investigate the impacts of foot lesions occurring around the time of first calving in heifers on future lameness risk, daily milk yield and survival within a dairy herd. Records were obtained for 158 heifers from one UK dairy herd. Heifers were examined in 2 month blocks from 2 months pre-calving through to 4 months post-calving. Sole lesions and white line lesions were scored on a zero to 10 scale and digital dermatitis on a zero to 3 scale. Outcomes investigated were; lameness risk based on weekly locomotion scores, average daily milk yield and culling risk. Mixed effect models were used to investigate associations between maximum lesion scores and outcomes. Lesion scores in the highest score categories for claw horn lesions (sole lesions and white line lesions) in the 2 to 4 month post-calving period were associated with an increased risk of future lameness; heifers with white line lesion scores ≥3 compared with scores zero to 1 and heifers with sole lesion scores ≥4 compared with score 2, at this time point, had a predicted increased risk of future lameness of 1.6 and 2.6 respectively. Sole lesions ≥4 were also associated with a reduction in average daily milk yield of 2.68 kg. Managing heifers to reduce claw horn lesions during this time period post-calving may provide health, welfare and production benefits for the long-term future of those animals. A novel finding from the study was that mild lesion scores compared with scores zero to 1, were associated with a reduced risk of future lameness for white line lesions and sole lesions occurring in the pre-calving or 2 to 4 months post-calving periods respectively. Mild sole lesions in the pre-calving period were also associated with a reduced risk of premature culling. One hypothesis for this result is that a mild insult may result in adaptive changes to the foot leading to greater biomechanical resilience and so increased longevity.

Prevalence and distribution of foot lesions in dairy cattle in Alberta, Canada

The objectives of this cross-sectional study were to determine the prevalence and distribution of foot lesions and associated cow- and herd-level risk factors in dairy cows in Alberta, Canada. Foot lesion data were recorded electronically by 7 hoof trimmers on 28,607 cows in 156 dairy farms from June 2009 to November 2012. Foot lesion prevalence estimates differed between farms that had the whole herd trimmed at once (≥80% of lactating cows were trimmed; n=69 farms and 8,020 cows) and farms on which part of the herd was trimmed (selection of cows was determined by farmer and <80% of lactating cows were trimmed; n=87 and 20,587 cows). Estimates were consistently higher for the latter likely because farmers presumably prioritized lame cows in partial-herd trims. On farms with whole-herd trims, digital dermatitis was the most common lesion among all housing types, present in 15% of cows and 94% of herds. Sole ulcers and white line disease were detected in 6 and 4% of the cows and 92 and 93% of herds, respectively. Other infectious and claw horn lesions each affected 1 to 2% of cows and 62 to 78% of herds. Intraclass correlation coefficients for hoof trimmers ranged from 0.01 to 0.20 for all lesions, indicating some clustering of recorded lesions by trimmer. Multilevel mixed logistic regression models were constructed (including hoof trimmer as fixed and farm as random effects) for the 3 most frequently identified lesions. Prevalence of digital dermatitis decreased with increasing parity, but this effect interacted with days in milk (DIM); primiparous cows had higher odds of digital dermatitis in mid lactation (100-199 DIM) and late lactation (≥200 DIM) compared with cows at other stages of lactation. In contrast, prevalence of sole ulcers and white line disease increased with increasing parity; compared with cows in parity 1, those in parity 4 had 5 or 7 times higher odds of having these lesions, respectively. Cows in mid lactation and late lactation had higher odds of sole ulcers and white line disease than cows at other stages of lactation, regardless of parity. Digital dermatitis prevalence was 2 times higher in herds housed in barns with access to an exercise area. The odds of sole ulcers and white line disease were ≥2 times higher in cows housed in freestalls than those housed in deep-bedded packs. Therefore, preventive measures for control of digital dermatitis merit emphasis, especially in primiparous cows and on farms with exercise areas. In addition, improving housing environment by providing a deep-bedded area for older cows in mid lactation or late lactation could reduce prevalence of claw horn lesions. We inferred that foot lesion data recorded by hoof trimmers can provide useful information not only to develop effective foot health programs at herd level, but also for disease surveillance and genetic improvement at regional and national levels.

Linking bone development on the caudal aspect of the distal phalanx with lameness during life

Claw horn disruption lesions (CHDL; sole hemorrhage, sole ulcer, and white line disease) cause a large proportion of lameness in dairy cattle, yet their etiopathogenesis remains poorly understood. Untreated CHDL may be associated with damage to the internal anatomy of the foot, including to the caudal aspect of the distal phalanx upon which bone developments have been reported with age and with sole ulcers at slaughter. The primary aim of this study was to assess whether bone development was associated with poor locomotion and occurrence of CHDL during a cow's life. A retrospective cohort study imaged 282 hind claws from 72 Holstein-Friesian dairy cows culled from a research herd using X-ray micro-computed tomography (μ-CT; resolution: 0.11mm). Four measures of bone development were taken from the caudal aspect of each distal phalanx, in caudal, ventral, and dorsal directions, and combined within each claw. Cow-level variables were constructed to quantify the average bone development on all hind feet (BD-Ave) and bone development on the most severely affected claw (BD-Max). Weekly locomotion scores (1-5 scale) were available from first calving. The variables BD-Ave and BD-Max were used as outcomes in linear regression models; the explanatory variables included locomotion score during life, age, binary variables denoting lifetime occurrence of CHDL and of infectious causes of lameness, and other cow variables. Both BD-Max and BD-Ave increased with age, CHDL occurrence, and an increasing proportion of locomotion scores at which a cow was lame (score 4 or 5). The models estimated that BD-Max would be 9.8mm (SE 3.9) greater in cows that had been lame at >50% of scores within the 12mo before slaughter (compared with cows that had been assigned no lame scores during the same period), or 7.0mm (SE 2.2) greater if the cow had been treated for a CHDL during life (compared with cows that had not). Additionally, histology demonstrated that new bone development was osteoma, also termed "exostosis." Age explained much of the variation in bone development. The association between bone development and locomotion score during life is a novel finding, and bone development appears specific to CHDL. Bone development on the most severely affected foot was the best explained outcome and would seem most likely to influence locomotion score. To stop irreparable anatomical damage within the foot, early identification of CHDL and effective treatment could be critical.

Applying animal-based welfare assessments on New Zealand dairy farms: feasibility and a comparison with United Kingdom data

AIMS

To assess the feasibility of applying animal-based welfare assessments developed for use in Europe on New Zealand dairy farms; in particular, to identify measures which could be evaluated during a single visit at milking time alongside whole herd locomotion scoring.

METHODS

A protocol for animal welfare assessment, developed in the United Kingdom (UK), was evaluated. Measures that were suitable for use on pasture-based dairy farms in New Zealand were then assessed for practicability on 59 farms across New Zealand, during and immediately after milking, alongside whole herd locomotion scoring. Where data were collected the results were compared to those from a UK study of 53 dairy farms.

RESULTS

Thirteen observations of the physical condition of cows were considered suitable for measurement, excluding observations related to hock lesions as they are rarely observed on pasture-based farms. Five of these measures were not assessed as there was not time to do so during milking alongside whole herd locomotion scoring. Thus, the prevalence of dirty flanks, hind limbs and udders, dull coat, thick hairy coat, significant hair loss, very fat cows (body condition score (BCS) ≥7 on 1-10 scale) and very thin cows (BCS≤3), were recorded. Three measures of behaviour were considered suitable for measurement on-farm, but only locomotion score was practicable and was measured. Farmer-estimates for the incidence of mastitis, lameness, sudden death, milk fever and other diseases were also obtained.Overall, dirty flanks, dirty udders and estimated milk fever incidence were more prevalent in this study than in the UK. The prevalence of thin and fat cows, lame cows and estimated mastitis incidence were much lower in the present study than on UK farms.

CONCLUSIONS AND CLINICAL RELEVANCE

Animal-based assessments can be used on dairy farms in New Zealand, but need to be modified from those developed for housed cows.Welfare on these farms was generally good compared to those in the UK, but these results need to be confirmed on more farms using a wider range of assessments than proved practicable in this study.

Lameness Prevalence and Risk Factors in Large Dairy Farms in Upstate New York. Model Development for the Prediction of Claw Horn Disruption Lesions

The main objectives of this prospective cohort study were a) to describe lameness prevalence at drying off in large high producing New York State herds based on visual locomotion score (VLS) and identify potential cow and herd level risk factors, and b) to develop a model that will predict the probability of a cow developing claw horn disruption lesions (CHDL) in the subsequent lactation using cow level variables collected at drying off and/or available from farm management software. Data were collected from 23 large commercial dairy farms located in upstate New York. A total of 7,687 dry cows, that were less than 265 days in gestation, were enrolled in the study. Farms were visited between May 2012 and March 2013, and cows were assessed for body condition score (BCS) and VLS. Data on the CHDL events recorded by the farm employees were extracted from the Dairy-Comp 305 database, as well as information regarding the studied cows’ health events, milk production, and reproductive records throughout the previous and subsequent lactation period. Univariable analyses and mixed multivariable logistic regression models were used to analyse the data at the cow level. The overall average prevalence of lameness (VLS > 2) at drying off was 14%. Lactation group, previous CHDL, mature equivalent 305-d milk yield (ME305), season, BCS at drying off and sire PTA for strength were all significantly associated with lameness at the drying off (cow-level). Lameness at drying off was associated with CHDL incidence in the subsequent lactation, as well as lactation group, previous CHDL and ME305. These risk factors for CHDL in the subsequent lactation were included in our predictive model and adjusted predicted probabilities for CHDL were calculated for all studied cows. ROC analysis identified an optimum cut-off point for these probabilities and using this cut-off point we could predict CHDL incidence in the subsequent lactation with an overall specificity of 75% and sensitivity of 59%. Using this approach, we would have detected 33% of the studied population as being at risk, eventually identifying 59% of future CHDL cases. Our predictive model could help dairy producers focusing their efforts on CHDL reduction by implementing aggressive preventive measures for high risk cows.

Prevalence of lameness and associated risk factors in Canadian Holstein-Friesian cows housed in freestall barns

Lameness is a severe welfare problem and a production-limiting disease in dairy farming. The objectives of this study were to determine prevalence of lameness and investigate cow- and herd-level factors associated with lameness in dairy cows housed in freestall barns in 3 Canadian provinces. A purposive sample of 40 Holstein-Friesian cows was selected from each of 141 dairy farms in Québec, Ontario, and Alberta. In total, 5,637 cows were scored once for lameness (presence of limping when walking). Data collected included information on individual cows (hock lesions, claw length, body condition score, parity, days in milk, and milk production), management practices (floor and stall cleaning routine, bedding routine, and footbath practices), and facility design (stall dimensions, stall base and bedding type, width of feed alley, flooring type, and slipperiness) hypothesized to be risk factors for lameness. Multilevel mixed logistic regression models were constructed (including farm as a random effect and province as a fixed effect). Herd-level lameness prevalence ranged from 0 to 69% (mean = 21%). Lameness prevalence increased with increasing parity; compared with first parity, cows in parity 2, 3, and ≥ 4 had 1.6, 3.3, and 4 times, respectively, higher odds of being lame. Furthermore, the odds of lameness were 1.6 times greater in cows with low body condition score (≤ 2.5) than in cows with a higher body condition score. In addition, injured hocks and overgrown claws were associated with 1.4- and 1.7-fold increased odds of being lame, respectively, whereas every 1 kg increase in daily milk production was associated with a 3% decrease in the odds of being lame. Lameness prevalence was higher in herds with ≤ 100 cows, but lower in barns with a sand or dirt stall base, or with bedding ≥ 2 cm deep. Cows exposed to very slippery floors had 2 times the odds of being lame compared with cows exposed to nonslippery floors. We attributed the wide range of lameness prevalence to the great variability in facilities and management practices among farms. Finally, we inferred that the prevalence of lameness could be decreased by improving management of multiparous, thin, or injured cows and by adopting management practices intended to improve cow comfort, namely the floor's slip resistance and the stall's lying surface.

Claw length recommendations for dairy cow foot trimming

The aim was to describe variation in length of the dorsal hoof wall in contact with the dermis for cows on a single farm, and hence, derive minimum appropriate claw lengths for routine foot trimming. The hind feet of 68 Holstein-Friesian dairy cows were collected post mortem, and the internal structures were visualised using x-ray µCT. The internal distance from the proximal limit of the wall horn to the distal tip of the dermis was measured from cross-sectional sagittal images. A constant was added to allow for a minimum sole thickness of 5 mm and an average wall thickness of 8 mm. Data were evaluated using descriptive statistics and two-level linear regression models with claw nested within cow. Based on 219 claws, the recommended dorsal wall length from the proximal limit of hoof horn was up to 90 mm for 96 per cent of claws, and the median value was 83 mm. Dorsal wall length increased by 1 mm per year of age, yet 85 per cent of the null model variance remained unexplained. Overtrimming can have severe consequences; the authors propose that the minimum recommended claw length stated in training materials for all Holstein-Friesian cows should be increased to 90 mm.

The effect of Lameness before and during the breeding season on fertility in 10 pasture-based Irish dairy herds

Background

The effects of lameness on fertility have been documented frequently but few data are available from seasonally breeding, pasture-based herds (such as those used in Ireland) where cows are housed during the winter months but managed at pasture for the remainder of the year. This study determined the prevalence of lameness in a group of 786 cows in 10 pasture-based Irish dairy herds before, during and after the breeding season and assessed the relationship between lameness and the reproductive performance in these herds through serial locomotion scoring during the grazing period.

Results

Lameness prevalences of 11.6 % before, 14.6 % during and 11.6 % after the breeding season were found and these compared favourably to results from housed cattle and are similar to other studies carried out in grazing herds. A Cox proportional hazards model with locomotion score as time varying covariate was used. After controlling for the effect of farm, month of calving, body condition score at calving, body condition score loss after calving and economic breeding index, cows identified as lame during the study were less likely to become pregnant. Cows lame before the earliest serve date but no longer lame during the breeding season, cows becoming lame after the earliest serve date and cows identified lame both before and after this date were respectively 12 %, 35 % and 38 % less likely to become pregnant compared to cows never observed lame during the study. However, these findings were only significant for cows becoming lame after the earliest serve date and cows lame both before and after the start of breeding.

Conclusions

This study found that the reproductive efficiency was significantly (p < 0.05) lower in cows becoming lame during the breeding season and cows lame before and during the breeding season compared to non-lame cows. Cows no longer lame during the breeding season had a lower Submission Rate to first serve within 3 weeks of earliest serve date. However, the Pregnancy Rate was not significantly (p > 0.05) lower in these animals compared to cows never diagnosed as lame. In addition to lameness status, nutritional status and genetics were found to influence the reproductive performance in pasture-based Irish dairy herds.

Area of hock hair loss in dairy cows: risk factors and correlation with a categorical scale

Data from 3691 dairy cows from 76 farms were used to investigate the risk factors associated with the area of hair loss over the lateral aspect of the hock and the correlation between the area of hair loss (as calculated using a hock map) and hock lesion scores determined using a pre-existing categorical scale. Six factors were associated with a greater area of hair loss, including cows with locomotion score 3, a cleanliness score (10/28 to 18/28), high daily milk yield (25.1-58.1 kg), poor body condition score (1-1.5), duration of winter housing (≥41 days) and some combinations of cubicle base and bedding materials. Compared with cows housed in cubicles with a concrete base and whole straw or rape straw bedding, cows housed in cubicles with concrete bases with sand or chopped straw bedding had smaller areas of hair loss and cows housed on a mattress base with whole straw or rape straw bedding had larger areas of hair loss. Area of hair loss, as measured on hock maps, was not significantly different between cows with score 1 (median 23.6 cm(2)) and score 2 (median 20.3 cm(2)) on the categorical scale for hock lesions. This suggests that the categorical scale was not reflecting the extent of hair loss and that hock maps are a good alternative for studying the dynamics of hock lesions over time.

Animal welfare and society concerns finding the missing link

Young adults in developed countries are distanced from agriculture and the meat industry needs to do a better job of communicating with them. A major welfare concern is slaughter without stunning. Other concerns, such as poor stunning or high levels of bruising, can be easily corrected by management who is committed to maintaining high standards. Another concern is biological system overload, occurring when animals are bred for more productivity. Researchers and industry need to determine optimum production levels instead of maximums. Retailers are major drivers of animal welfare standards enforcement and they respond to pressure from both activists and consumers.