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

Observational study evaluating the association of hoof trimming with dairy cattle behavior and milk yield in Canada and the United Kingdom

The objective of this observational study was to describe the associations between preventive hoof trimming (HT) of cows with no lesions and several behavior- and productivity-outcome measures including activity, lying behavior, and milk yield. A convenience sample of 4 freestall farms in the United Kingdom (n = 2) and Canada (n = 2) were recruited for the study. Inclusion criteria for herds included having a regular trim schedule and use of a specific pedometer system. Cows were trimmed as per their farm's regular protocol and schedule and all HT events were recorded. Only cows with no lesions present on the first recorded HT event were used in the analysis. Activity (steps/d), resting time (min/d), and resting bouts (bouts/d) were recorded daily by pedometers and total daily milk yield (kg/d) was recorded by the farm's milk recording system. Cow-level data such as DIM, breed, and parity were collected from the farm's herd management software. A generalized linear mixed repeated measures model with an exchangeable correlation structure was built to compare the outcome for 7 d following HT to baseline measures for each outcome of interest. For each outcome the average from the 5 d before HT was used as a baseline. All models included the baseline status, lactation number, season, farm, and DIM as covariates. Days from HT and its interaction with farm were included in all models. A total of 1,573 cows with no lesion recorded in their first HT were included in the analysis. Activity and resting time were inversely related on the day of HT, with activity increasing on 3 out of 4 farms (+59 to +84 steps/d) and resting time decreasing (-28 to -52 min/d). Following the day of HT, activity decreased to levels lower than those reported at baseline and resting time increased compared with baseline on most farms. There was a reduction in milk yield on the day of HT on 3 out of 4 farms and a reduction in average yield across the 7 d following trimming for all farms (range: 0.6 to 1.3 kg/d). Results were found to be farm dependent. The impact of the degree of change from baseline in behaviors and milk yield reported in this study on welfare of the cow is unclear, but the results suggest that alterations in the outcomes evaluated can persist beyond the day of trimming compared with baseline, necessitating further investigation.

Association between a genetic index for digital dermatitis resistance and the presence of digital dermatitis, heel horn erosion, and interdigital hyperplasia in Holstein cows

Digital dermatitis (DD) is a polybacterial disease endemic to most UK dairy farms. It poses a major financial and welfare threat and is characterized by high incidence and recurrence rates. We aimed to investigate the association between the UK EBV for resistance to digital dermatitis, the digital dermatitis index (DDI), and the frequency of DD, heel horn erosion (HHE), and interdigital hyperplasia (IH) in a population of Holstein dairy cows. We enrolled and genotyped 2,352 cows from 4 farms in a prospective cohort study. Foot lesion records were recorded by veterinary surgeons for each animal at 4 time points during a production cycle, starting at approximately 2 mo before calving and ending in late lactation. Importantly, these records were not used in the calculation of the DDI. Lesion records were matched to the animal's own DDI (n = 2,101) and their sire's DDI (n = 1,812). Digital dermatitis index values in our study population ranged from -1.41 to +1.2 and were transformed to represent distance from the mean expressed in SD. The relationship between the DDI and the presence of DD was investigated using a logistic regression model, with farm, parity, and a farm-parity interaction fitted as covariates. A multivariable logistic regression model was fitted to evaluate the relationship between HHE and DDI with farm fitted as a covariate. Finally, a univariable logistic regression model with DDI as explanatory variable was used to investigate the relationship between IH and DDI. The odds ratio of an animal being affected by DD was 0.69 for 1 SD increase in the animal's DDI (95% CI = 0.63-0.76). The odds of HHE and IH were 0.69 (95% CI = 0.62-0.76) and 0.58 (95% CI = 0.49-0.68) respectively for 1 SD increase in DDI. The adjusted probability of DD was 32% (95% CI = 27-36%) for cows with mean DDI value of 0, while it was 24% (95% CI = 20-29%) in cows with a DDI value of +1. Sire DDI breeding values were standardized in the same way and then binned into terciles creating an ordinal variable representing bulls of high, medium, and low genetic merit for DD resistance. The daughters of low genetic merit bulls were at 2.05 (95% CI = 1.60-2.64), 1.96 (95% CI = 1.53-2.50), and 2.85 (95% CI = 1.64-5.16) times greater odds of being affected by DD, HHE, and IH, respectively, compared with the daughters of high genetic merit bulls. The results of this study highlight the potential of digital dermatitis genetic indexes to aid herd management of DD, and suggest that breeding for resistance to DD, alongside environmental and management control practices, could reduce the prevalence of the disease.

Lameness in Cattle-Etiopathogenesis, Prevention and Treatment

The aim of this review was to analyse the health problem of lameness in dairy cows by assessing the health and economic losses. This review also presents in detail the etiopathogenesis of lameness in dairy cattle and examples of its treatment and prevention. This work is based on a review of available publications. In selecting articles for the manuscript, the authors focused on issues observed in cattle herds during their clinical work. Lameness in dairy cattle is a serious health and economic problem around the world. Production losses result from reduced milk yield, reduced feed intake, reproductive disorders, treatment costs, and costs associated with early culling. A significant difficulty in the control and treatment of lameness is the multifactorial nature of the disease; causes may be individual or species-specific and may be associated with the environment, nutrition, or the presence of concomitant diseases. An important role is ascribed to infectious agents of both systemic and local infections, which can cause problems with movement in animals. It is also worth noting the long treatment process, which can last up to several months, thus significantly affecting yield and production. Given the high economic losses resulting from lameness in dairy cows, reaching even >40% (depending on the scale of production), there seems to be a need to implement extensive preventive measures to reduce the occurrence of limb infections in animals. The most important effective preventive measures to reduce the occurrence of limb diseases with symptoms of lameness are periodic hoof examinations and correction, nutritional control, and bathing with disinfectants. A clean and dry environment for cows should also be a priority.

Invited review: Prevalence, risk factors, treatment, and barriers to best practice adoption for lameness and injuries in dairy cattle-A narrative review

Lameness and leg injuries are both painful and prevalent across the dairy industry, and are a major welfare concern. There has been a considerable amount of research focused on investigating the risk factors associated with lameness and injuries and how they might be prevented and treated. The objectives of this narrative review were to summarize herd-level prevalence estimates, risk factors, strategies for prevention, control, and treatment of these conditions, and the barriers to best practice adoption for lameness and injuries on dairy farms. There is a relatively high within-herd prevalence of lameness on dairy farms globally, with a recent systematic review estimating the mean prevalence at 22.8%. Similarly, there is a relatively high prevalence of hock injuries, with within-herd estimates ranging from 12% to 81% of cows affected. Knee and neck injuries have been reported to be less common, with 6% to 43% and 1% to 33%, respectively. Numerous risk factors have been associated with the incidence of lameness, notably housing (e.g., access to pasture, bedding depth, bedding type, flooring type, stall design), management (e.g., stall cleanliness, frequency of trimming, holding times, stocking density), and cow-level (e.g., body condition, parity, injured hocks) factors. Risk factors associated with hock injuries can be similarly classified into housing (e.g., bedding type and depth, outdoor access, parlor type, stall design), management (e.g., bedding depth, cleanliness), and cow (e.g., parity, days in milk, lameness) factors. Key preventative approaches for lameness include routine preventative and corrective hoof trimming, improving hoof cushioning and traction through access to pasture or adding rubber flooring, deep-bedded stalls, sand bedding, ensuring appropriate stocking densities, reduced holding times, and the frequent use of routine footbaths. Very little research has been conducted on hock, knee, and neck injury prevention and recovery. Numerous researchers have concluded that both extrinsic (e.g., time, money, space) and intrinsic (e.g., farmer attitude, perception, priorities, and mindset) barriers exist to addressing lameness and injuries on dairy farms. There are many diverse stakeholders in lameness and injury management including the farmer, farm staff, veterinarian, hoof trimmer, nutritionist, and other advisors. Addressing dairy cattle lameness and injuries must, therefore, consider the people involved, as it is these people who are influencing and implementing on-farm decisions related to lameness prevention, treatment, and control.

Assessing lameness prevalence and associated risk factors in crossbred dairy cows across diverse management environments

BACKGROUND

A thorough understanding of lameness prevalence is essential for evaluating the impact of this condition on the dairy industry and assessing the effectiveness of preventive strategies designed to minimize its occurrence. Therefore, this cross-sectional study aimed to ascertain the prevalence of lameness and identify potential risk factors associated with lameness in Holstein Friesian crossbred cows across both commercial and smallholder dairy production systems in Bengaluru Rural District of Karnataka, India.

METHODS

The research encompassed six commercial dairy farms and 139 smallholder dairy farms, involving a total of 617 Holstein Friesian crossbred cattle. On-site surveys were conducted at the farms, employing a meticulously designed questionnaire. Lameness in dairy cattle was assessed subjectively using a locomotion scoring system. Both bivariate and binary logistic regression models were employed for risk assessment, while principal components analysis (PCA) was conducted to address the high dimensionality of the data and capture the underlying structure of the explanatory variables.

RESULTS

The overall lameness prevalence of 21.9% in commercial dairy farms and 4.6% in smallholder dairy farms. Various factors such as age, body weight, parity, body condition score (BCS), floor type, hock and knee injuries, animal hygiene, provision of hoof trimming, and the presence of hoof lesions were found to be significantly associated with lameness. Binary logistic regression analysis indicated that the odds of lameness in crossbred cows increased with higher parity, decreased BCS, presence of hard flooring, poor animal hygiene, and the existence of hoof lesions. These factors were identified as potential risk factors for lameness in dairy cows. Principal component analysis unveiled five components explaining 71.32% of the total variance in commercial farms and 61.21% in smallholder dairy farms. The extracted components demonstrated higher loadings of housing and management factors (such as hoof trimming and provision of footbath) and animal-level factors (including parity, age, and BCS) in relation to lameness in dairy cows.

CONCLUSIONS

The findings suggest that principal component analysis effectively reduces the dimensionality of risk factors. Addressing these identified risk factors for lameness is crucial for the strategic management of lameness in dairy cows. Future research in India should investigate the effectiveness of management interventions targeted at the identified risk factors in preventing lameness in dairy cattle across diverse environments.

Associations of cow and farm characteristics with cow-level lameness using data from an extensive cross-sectional study across 3 structurally different dairy regions in Germany

The aim of the present study was to evaluate the associations between milk recording data, body condition score (BCS), housing factors, management factors, and lameness in freestall-housed dairy cows in 3 structurally different regions in Germany. These regions substantially vary regarding herd size, breeds, access to pasture, farm management (family run or company owned), and percentage of organic farms. The data used was collected in a large cross-sectional study from 2016 to 2019. A total of 58,144 cows from 651 farms in 3 regions of Germany (North, East, and South) was scored for locomotion and body condition. Additionally, data on milk yield, milk composition, breed, age, as well as information on housing and management were retrieved. One mixed-logistic regression model was fitted per region to evaluate the association of the data with the target variable "lame" and to allow for a comprehensive reflection across different kinds of farming types. In all regions, undercondition (BCS lower than recommended for the lactation stage; North: odds ratio [OR] 2.15, CI 1.96-2.34; East: OR 2.66, CI 2.45-2.88; South: OR 2.45, CI 2.01-2.98) and mid-lactation stage (102-204 d in milk; North: OR 1.15, CI 1.05-1.27; East: OR 1.24, CI 1.17-1.32; South: OR 1.38, CI 1.18-1.62) were associated with higher odds for lameness, whereas overcondition (BCS higher than recommended for the lactation stage; North: OR 0.51, CI 0.44-0.60; East: OR 0.51, CI 0.48-0.54; South: OR 0.65, CI 0.54-0.77) and parity of 1 or 2 was associated with lower odds (parity 1 = North: OR 0.32, CI 0.29-0.35; East: OR 0.19, CI 0.18-0.20; South: OR 0.28, CI 0.24-0.33; parity 2 = North: OR 0.51, CI 0.47-0.46; East: OR 0.41, CI 0.39-0.44; South: OR 0.49, CI 0.42-0.57), irrespective of the regional production characteristics. Low energy-corrected milk yield was associated with higher odds for lameness in South and North (North: OR 1.16, CI 1.05-1.27; South: OR 1.43, CI 1.22-1.69). Further factors such as pasture access for cows (North: OR 0.64, CI 0.50-0.82; and South: OR 0.65, CI 0.47-0.88), milk protein content (high milk protein content = North: OR 1.34, CI 1.18-1.52; East: OR 1.17, CI 1.08-1.28; low milk protein content = North: OR 0.79, CI 0.71-0.88; East: OR 0.84, CI 0.79-0.90), and breed (lower odds for "other" [other breeds than German Simmental and German Holstein] in East [OR 0.47, CI 0.42-0.53] and lower odds both for German Holstein and "other" in South [German Holstein: OR 0.62, CI 0.43-0.90; other: OR 0.46, CI 0.34 - 0.62]) were associated with lameness in 2 regions, respectively. The risk of ketosis (higher odds in North: OR 1.11, CI 1.01-1.22) and somatic cell count (higher odds in East: increased (>39.9 cells × 1,000/mL): OR 1.10; CI 1.03-1.17; high (>198.5 cells × 1,000/mL): OR 1.08; CI 1.01-1.06) altered the odds for lameness in 1 region, respectively. Cows from organic farms had lower odds for lameness in all 3 regions (North: OR 0.18, CI 0.11-0.32; East: OR 0.39, CI 0.28-0.56; South: OR 0.45, CI 0.29-0.68). As the dairy production systems differed substantially between the different regions, the results of this study can be viewed as representative for a wide variety of loose-housed dairy systems in Europe and North America. The consistent association between low BCS and lameness in all regions aligns with the previous literature. Our study also suggests that risk factors for lameness can differ between geographically regions, potentially due to differences in which dairy production system is predominantly used and that region-specific characteristics should be taken into account in comparable future projects.

A multistate modeling approach to investigate long-term effects of claw horn disruption lesions and early lesion development in dairy cows

Claw horn disruption lesions (CHDL) are a leading cause of lameness in dairy cattle, and the development, effect, and pathology of these lesions remains an open area of interest within dairy cattle health. Current literature typically attempts to measure the effect of risk factors on the development of CHDL over a relatively short time period. Further understanding of the interaction of CHDL and the long-term effect of early CHDL in a cow's life remains an important area of research which is so far mostly unexplored. In this study 57,974 cows from 1,332 herds were selected and their regular claw trimming records containing important claw health information were used to model the long-term effect of lesions in a cow's lifetime in a 6-state multistate model. A multistate model predicts the time before transition from any one state to another and the probability of transition to a future state. The 6 lesion states that were modeled were as follows: never had a lesion, first recorded lesion event, no recorded lesion after first lesion event, second or subsequent recorded lesion event, no recorded lesion after second or subsequent lesion event, and culled. The effect of various cow level covariates on the transition probabilities between various states was tested. For the first time, this study shows the importance and effect of the first lesion and other cow level factors on long-term claw health. Model results showed that the timing and severity of the first recorded lesion event significantly influenced the likelihood of a future lesion being present. Cows with CHDL present within the 180 d of first calving had a short-term increased risk and long-term decreased risk of a future lesion, compared with cows that present with CHDL later than 180 d of first lactation. Moreover, presence of a severe first lesion increased a cow's risk of a future lesion being present. The model was used to evaluate the relative difference between high-risk cows (age of first calving ≥793 d, breeding values in the lowest quartile) and low-risk cows (age of first calving ≤718 d, breeding values in the highest quartile). Our results indicated that these low-risk cows present with a lesion on an average 3 mo later than high-risk cows. Furthermore, results from the model evaluation of a simulated herd with cows with breeding values in the higher quartile indicated that cows present with a CHDL on an average 7.5 mo later compared with a herd where cows have breeding values distributed in a lower quartile.

Non-linear change in body condition score over lifetime is associated with breed in dairy cows in Germany

Optimal body condition is crucial for the well-being and optimal productivity of dairy cows. However, body condition depends on numerous, often interacting factors, with complex relationships between them. Moreover, most of the studies describe the body condition in Holstein cattle, while condition of some breeds, e.g. Simmental (SIM) and Brown Swiss (BS) cattle, have not been intensively studied yet. Body condition score (BCS) proved to be one of the most effective measures for monitoring body condition in dairy cows. Alterations in BCS were previously mainly studied over a single lactation period, while changes over the lifetime were largely ignored. This study was designed to report BCS of German SIM and BS cows in the light of the broadly accepted BCS in German Holstein (GH) cows and to explore patterns of change in BCS over the productive lifetime of animals. BCS was modeled via linear mixed effects regression, over- and undercondition of animals were studied using mixed effects logistic regressions and condition of animals was explored with the multinomial log-linear model via neural networks. All models included an interaction between breed and age. We found BCS of SIM and BS to be higher than BCS of GH. Our results show that BCS of BS cows did not change over the lifetime. In contrast, the BCS of GH and SIM was found to have a non-linear (quadratic) shape, where BCS increased up to the years of highest productivity and then decreased in aging cows. Patterns of change between SIM and GH, however, differed. GH do not only reach their highest BCS earlier in life compared to SIM, but also start to lose their body condition earlier. Our dataset revealed that 23% of the animals scored were over- and 14% underconditioned. The proportion of cows that were overconditioned was high (>10% of cows) for every breed and every age, while severe underconditioning (>10% of cows) occurred only in middle aged and old GH. Moreover, we found that the probability of underconditioning of animals over lifetime increases, while the overconditioning decreases from the middle to older ages. Our findings highlight the importance of understanding the non-linear nature of BCS, and uncover the potential opportunity for improving the performance and welfare of dairy cows by adjusting their nutrition, not only during lactation, but also highly specific to breed and age.

Decision tree analysis to evaluate risks associated with lameness on dairy farms with automated milking systems

Lameness is an endemic disorder causing health problems and production losses in the dairy cow industry. The objective of this study was to identify cow and farm-level factors associated with lameness on Automatic Milking System (AMS) farms, using decision tree analysis to assign probabilities to each input. AMS farms across Canada and Michigan were evaluated to identify the most substantial farm (i.e., stall design, bedding) and cow-level (i.e., BCS, leg injuries) factors associated with prevalence of lameness. To assess lameness, videos of cows were used, and cows with a head bob or noticeable limp were categorized as lame. A decision tree classification model used 1378 data points from 39 pens across 36 farms to predict the value of the target class through “tree function” in MATLAB. The primary classifier was identified as type of stall base, dividing the data set into 3 categories: 1) rubber, sand, or geotextile mat flooring, 2) concrete base, and 3) other types of stall base. Within the first category (class membership (CM) = 976), bedding quantity was the secondary classifier, which was divided by cows standing on ≥2 cm (CM=456) or <2 cm (CM=520) of bedding. Bedding quantity was divided into the third most important classifier of BCS, and cow fit stall width. Cows with BCS of 3.25 to 4.5 (CM=307) were defined as non-lame with an estimated probability (EP) of 0.59, while cows with BCS of 2 to 2.5 (CM=213) were further split by hock lesion incidence. Cows without lesions were defined non-lame (EP=0.93) and cows with lesions were defined lame (EP=0.07). Cows that fit stall width were defined as non-lame (EP=0.66) and cows that did not fit were further divided by the width of the feed alley. Farms with ≥430 cm feed alley were defined as non-lame (EP=0.89), whereas farms with <430 cm feed alley were defined as lame (EP=0.11). Through implementing a novel multifactorial approach of data analysis, we were able to highlight the critical points that can be focused on to enhance farm-level housing and management practices or mitigate or monitor cow-level issues to reduce incidence and severity of lameness in AMS farms.

Genetic parameters and genome-wide association study of digital cushion thickness in Holstein cows

The digital cushion is linked to the development of claw horn lesions (CHL) in dairy cattle. The objectives of this study were to (1) estimate genetic parameters for digital cushion thickness (DCT), (2) estimate the genetic correlation between DCT and CHL, and (3) identify candidate genes associated with DCT. A cohort of 2,352 Holstein dairy cows were prospectively enrolled on 4 farms and assessed at 4 time points: before calving, immediately after calving, in early lactation, and in late lactation. At each time point, CHL was recorded by veterinary surgeons, and ultrasonographic images of the digital cushion were stored and retrospectively measured at 2 anatomical locations. Animals were genotyped and pedigree details extracted from the national database. Genetic parameters were estimated following a single-step approach implemented in AIREMLF90. Four traits were analyzed: the 2 DCT measurements, sole lesions (sole hemorrhage and sole ulcers), and white line lesions. All traits were analyzed with univariate linear mixed models; bivariate models were fit to estimate the genetic correlation between traits within and between time points. Single-marker and window-based genome-wide association analyses of DCT traits were conducted at each time point; candidate genes were mapped near (<0.2 Mb) or within the genomic markers or windows with the largest effects. Heritability estimates of DCT ranged from 0.14 to 0.44 depending on the location of DCT measurement and assessment time point. The genetic correlation between DCT and sole lesions was generally negative, notably between DCT immediately after calving and sole lesions in early or late lactation, and between DCT in early or late lactation and sole lesion severity in early or late lactation. Digital cushion thickness was not genetically correlated with white line lesions. A polygenic background to DCT was found; genes associated with inflammation, fat metabolism, and bone development were mapped near or within the top markers and windows. The moderate heritability of DCT provides an opportunity to use selective breeding to change DCT in a population. The negative genetic correlation between DCT and sole lesions at different stages of production lends support to current hypotheses of sole lesion pathogenesis. Highlighted candidate genes provide information regarding the complex genetic background of DCT in Holstein cows, but further studies are needed to explore and corroborate these findings.

Measuring lameness prevalence: Effects of case definition and assessment frequency

Lameness assessments are commonly conducted at a single point in time, but such assessments are subject to multiple sources of error. We conducted a longitudinal study, assessing the gait of 282 lactating dairy cows weekly during the first 12 wk of lactation, with the aim of assessing how lameness prevalence changed in relation to case definition and assessment frequency. Gait was scored using a 5-point scale where scores of 1 and 2 were considered sound, 3 was clinically lame, and 4 and 5 were severely lame. We created 5 lameness definitions using increasingly stringent thresholds based upon the number of consecutive events of locomotion score ≥3. In LAME1, a cow was considered lame when locomotion score was ≥3 at any scoring event, in LAME2, LAME3, LAME4, and LAME5, a cow was considered lame when locomotion score was 3 or higher during 2, 3, 4, and 5 consecutive scoring events, respectively. We also assessed the effect of assessment frequency on measures of prevalence and incidence using weekly assessment (ASSM1), 1 assessment every 2 wk (ASSM2), 1 assessment every 3 wk (ASSM3), and 1 assessment every 4 wk (ASSM4). Using LAME1, 69.2% of cows were considered lame at some point during the trial, with an average point prevalence of 31.8% (SD: 2.8) and average incidence rate of 10.9 cases/100 cow weeks (SD: 3.7). Lameness prevalence decreased to 28.0% when using LAME5. Survival analysis was used to assess the effects of parity, using these different case definitions. Parity is a known risk for lameness, such that case definitions and prevalence estimates should be stratified by parity to inform management decisions. Using the LAME3 criterion, primiparous cows had the highest chance of reaching 12 wk without a lameness event, and fourth and higher parities had the lowest. Weighted linear and quadratic kappa values were used to assess agreement between different assessment frequencies and lameness definitions; we found substantial to excellent agreement between ASSM1 and ASSM2 using LAME1, LAME2, and LAME3 definitions. Agreement was fair to substantial between ASSM1 and ASSM3 and low to fair between ASSM1 and ASSM4. Likewise, the agreement between LAME1 and LAME2 was fair in primiparous cows, substantial in second and third parity cows, and poor to fair in fourth and greater parity cows. We conclude that lameness prevalence estimates are dependent upon case definition and that the use of more stringent case definitions results in fewer cows classified as lame. These results suggest that routine locomotion assessments be conducted at least every 2 wk, and that cows should be defined as lame on the basis of 2 consecutive assessments.

A machine learning approach using partitioning around medoids clustering and random forest classification to model groups of farms in regard to production parameters and bulk tank milk antibody status of two major internal parasites in dairy cows

Fasciola hepatica and Ostertagia ostertagi are internal parasites of cattle compromising physiology, productivity, and well-being. Parasites are complex in their effect on hosts, sometimes making it difficult to identify clear directions of associations between infection and production parameters. Therefore, unsupervised approaches not assuming a structure reduce the risk of introducing bias to the analysis. They may provide insights which cannot be obtained with conventional, supervised methodology. An unsupervised, exploratory cluster analysis approach using the k–mode algorithm and partitioning around medoids detected two distinct clusters in a cross-sectional data set of milk yield, milk fat content, milk protein content as well as F. hepatica or O. ostertagi bulk tank milk antibody status from 606 dairy farms in three structurally different dairying regions in Germany. Parasite–positive farms grouped together with their respective production parameters to form separate clusters. A random forests algorithm characterised clusters with regard to external variables. Across all study regions, co–infections with F. hepatica or O. ostertagi, respectively, farming type, and pasture access appeared to be the most important factors discriminating clusters (i.e. farms). Furthermore, farm level lameness prevalence, herd size, BCS, stage of lactation, and somatic cell count were relevant criteria distinguishing clusters. This study is among the first to apply a cluster analysis approach in this context and potentially the first to implement a k–medoids algorithm and partitioning around medoids in the veterinary field. The results demonstrated that biologically relevant patterns of parasite status and milk parameters exist between farms positive for F. hepatica or O. ostertagi, respectively, and negative farms. Moreover, the machine learning approach confirmed results of previous work and shed further light on the complex setting of associations a between parasitic diseases, milk yield and milk constituents, and management practices.

Using a target trial approach to evaluate the role of hyperketonemia in sole ulcer and white line hoof lesion development

This observational cohort study enrolled cows from 7 freestall dairy herds in Minnesota and Wisconsin. The objective was to estimate the causal role of hyperketonemia on new sole ulcer and white line hoof lesions (SUWL). Multiparous cows were enrolled at the time of their precalving hoof trim, at the end of their previous lactation. Enrolled cows were hoof trimmed twice: precalving between 90 to 21 d before calving (n = 2,037), and postcalving between 21 to 150 d after calving (n = 1,408). We trained 7 commercial hoof trimmers, employed by the farms, in lesion identification to standardize lesion recording. Hoof trimmers conducted therapeutic trimming as well as diagnosing and treating lesions. After parturition, cows between 3 and 16 d in milk were tested once weekly for hyperketonemia using a hand-held ketone meter. Farm staff and research personnel conducted the β-hydroxybutyrate (BHB) testing. Cows were classified as hyperketonemic (HYK+) if they had a blood BHB ≥1.2 mmol/L or hyperketonemia-negative (HYK-) if blood BHB <1.2 mmol/L. At the precalving hoof trim, 15.6% of cows trimmed had a lesion and 1.9% of cows had a SUWL; thus, cows with a SUWL were excluded from further analysis (n = 38). At the postcalving hoof trim, 25.8% of cows trimmed had a hoof lesion, and 3.6% of cows had a SUWL. The most prevalent lesions at the pre- and postcalving hoof trims were digital dermatitis and corkscrew lesions. The incidence of hyperketonemia among cows was 21.1% (421/1,999) and the incidence on farms ranged from 5.7 to 29.1%. After excluding cows due to being hoof trimmed outside our designated window, the multilevel logistic regression model for the odds of SUWL at the postcalving hoof trim included 1,209 cows (HYK+ = 257/1,209; SUWL = 42/1,209). The odds of having SUWL in HYK+ was 0.66 (95% confidence interval: 0.29, 1.49) times the odds of that for HYK- cows. For cows diagnosed with a lesion (digital dermatitis, corkscrew, toe, foot rot, or other lesion) at their precalving hoof trim (n = 199), the odds of having SUWL for HYK+ cows were 0.43 (95% confidence interval: 0.05, 3.92) times the odds of that for HYK- cows. The wide range of compatible causal estimates suggest that hyperketonemia likely has a limited role in the development of SUWL in cows with or without a hoof lesion precalving. Future research should investigate other transition period factors such as inflammation or structural changes to the foot that may have a causative role in the development of SUWL.

Prevalence of Sole ulcer in Dairy Cows Exposed to Heat Stress

The aim of this study was to investigate the seasonal thermal effect on the prevalence of the sole ulcer in dairy cows. The observations were performed on a Holstein-Friesian (HF) dairy farm in Eastern Slovakia. The clinical signs of heat stress were recognised in several animals during the afternoon milking on July 8, 2015. The claw examination done three months after the heat stress episode was compared with three examinations: twelve and two months prior to the heat stress and ten months afterward. The orthopaedic examinations were focused on the prevalence of the sole ulcer. Statistical analysis was performed by running a chi-squared test. The temperature-humidity index (THI) on July 8, 2015, was 88. We found 15.2 %, 18.6 %, 28.1 %, and 12.9 % cows with sole ulcer in the autumn 2014, spring 2015, autumn 2015, and spring of the following year, respectively (P < 0.05). In conclusion, the results of our observations showed that the heat stress in dairy cows can be associated with an increase in the prevalence of the sole ulcer.

Acute phase response of sole ulcer, white line disease and digital dermatitis in dairy cows

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Serum amyloid A, a marker of inflammation, was still elevated two weeks after treatment of sole ulcers.

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Body temperature and concentration of cytokine interleukin-6 declined from day 0 to day 7 in sole ulcer group.

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Sole ulcer is a chronic hoof disorder that heals slowly and therefore early detection, good management, and proper pain medication of cows with sole ulcers is important.

Hoof disorders cause lameness and welfare problems for dairy cattle. Acute phase proteins, including serum amyloid A and haptoglobin, with increased rectal temperature and interleukin-6 concentrations, are markers of acute phase response. This study assessed the inflammatory response of cows with either sole ulcer, white line disease or digital dermatitis compared to healthy cows. Another aim was to monitor the inflammatory response changes over time after diagnosis (at hoof trimming, seven and 14 days later) in cows with different hoof disorders.

Serum amyloid A concentration in cows with sole ulcer was significantly higher compared with the control group (cows with no hoof lesions) within the two-week study period. Interleukin-6 and rectal temperature declined from day zero to day seven in the sole ulcer group. These results suggest that sole ulcers initiate a long lasting systemic inflammatory response in dairy cows.

Historical Evolution of Cattle Management and Herd Health of Dairy Farms in OECD Countries

This work aimed to review the important aspects of the dairy industry evolution at herd level, interrelating production with health management systems. Since the beginning of the industrialization of the dairy cattle sector (1950s), driven by the need to feed the rapidly growing urban areas, this industry has experienced several improvements, evolving in management and technology. These changes have been felt above all in the terms of milking, rearing, nutrition, reproductive management, and design of facilities. Shortage of labor, emphasis on increasing farm efficiency, and quality of life of the farmers were the driving factors for these changes. To achieve it, in many areas of the world, pasture production has been abandoned, moving to indoor production, which allows for greater nutritional and reproductive control of the animals. To keep pace with this paradigm in milk production, animal health management has also been improved. Prevention and biosecurity have become essential to control and prevent pathologies that cause great economic losses. As such, veterinary herd health management programs were created, allowing the management of health of the herd as a whole, through the common work of veterinarians and farmers. These programs address the farms holistically, from breeding to nutrition, from prevention to consultancy. In addition, farmers are now faced with a consumer more concerned on animal production, valuing certified products that respect animal health and welfare, as well as environmental sustainability.

Symposium review: The role of adipose tissue in transition dairy cows: Current knowledge and future opportunities

Adipose tissue (AT) is a central reservoir of energy stored in the form of lipids. In addition, AT has been recognized as an immunologically and endocrinologically active tissue of dairy cattle. The recent literature on AT biology of transition dairy cows has often focused on the possible negative effects that originate from excessive body fat. However, the highly efficient energy-storage capability of this tissue is also vital to the adaptability of dairy cattle to the change in nutrient availability, and to support lactation and reproduction. An excessive degree of mobilization of this tissue, however, is associated with high circulating fatty acid concentrations, and this may have direct and indirect negative effects on reproductive health, productivity, and disease risk. Furthermore, rapid lipolysis may be associated with postpartum inflammation. Research on the role of AT is complicated by the greater difficulty of accessing and measuring visceral AT compared with subcutaneous AT. The objective of this review is to provide a transition cow-centric summary of AT biology with a focus on reviewing methods of measuring AT mass as well as to describe the importance for production, health, and reproductive success.

Time-Consuming, but Necessary: A Wide Range of Measures Should Be Included in Welfare Assessments for Dairy Herds

Animal welfare assessments that measure welfare outcomes, including behavior and health, can be highly valid. However, the time and skill required are major barriers to their use. We explored whether feasibility of welfare outcome assessment for dairy herds may be improved by rationalizing the number of measures included. We compared two approaches: analyzing whether strong pairwise associations between measures existed, enabling the subsequent exclusion of associated measures; and identifying possible summary measures—“iceberg indicators”—of dairy herd welfare that could predict herd welfare status. A cross-sectional study of dairy herd welfare was undertaken by a single assessor on 51 English farms, in which 96 welfare outcome measures were assessed. All measures showed at least one pairwise association; percentage of lame cows showed the most (33 correlations). However, most correlations were weak–moderate, suggesting limited scope for excluding measures from protocols based on pairwise relationships. A composite measure of the largest portion of herd welfare status was then identified via Principal Component Analysis (Principal Component 1, accounting for 16.9% of variance), and linear regression revealed that 22 measures correlated with this. Of these 22, agreement statistics indicated that percentage of lame cows and qualitative descriptors of “calmness” and “happiness” best predicted Principal Component 1. However, even these correctly classified only ~50% of farms according to which quartile of the Principal Component 1 they occupied. Further research is recommended, but results suggest that welfare assessments incorporating many diverse measures remain necessary to provide sufficient detail about dairy herd welfare.

A systematic approach to analyse the impact of farm-profiles on bovine health

In this study we present systematic framework to analyse the impact of farm profiles as combinations of environmental conditions and management practices on common diseases in dairy cattle. The data used for this secondary data analysis includes observational data from 166 farms with a total of 5828 dairy cows. Each farm is characterised by features from five categories: husbandry, feeding, environmental conditions, housing, and milking systems. We combine dimension reduction with clustering techniques to identify groups of similar farm attributes, which we refer to as farm profiles. A statistical analysis of the farm profiles and their related disease risks is carried out to study the associations between disease risk, farm membership to a specific cluster as well as variables that characterise a given cluster by means of a multivariate regression model. The disease risks of five different farm profiles arise as the result of complex interactions between environmental conditions and farm management practices. We confirm previously documented relationships between diseases, feeding and husbandry. Furthermore, novel associations between housing and milking systems and specific disorders like lameness and ketosis have been discovered. Our approach contributes to paving a way towards a more holistic and data-driven understanding of bovine health and its risk factors.

Status of claw recordings and claw health in Danish dairy cattle from 2013 to 2017

Since 2009, Danish claw trimmers have been able to record claw health digitally during trimming. The records are owned by the farmer and can be used locally in the herd and on a large scale by breeding organisations to improve claw health. The objective of this study was to describe data on claw recording routines and describe the prevalence of digital dermatitis (DD), interdigital hyperplasia (IH), sole ulcer (SU) and white line abscess (WLA) recorded by claw trimmers (TrimmerID) at trimming. More than 5.18 million records of cows with claw recordings and 2.75 million records of claw trimming with 2.4 million concurrent claw diseases from 62 TrimmerIDs from 705,803 animals from 1635 herds over a 5-year period from 2013 to 2017 were included in the dataset. Data on cow level was used for the descriptive statistics. The data was restricted to, and grouped by, heifers from 12 months of age, first, second and third or older parity cows from the breeds Holstein, Danish Red Dairy, Jersey and crossbreds. The number of recorded trimmings per TrimmerID per year varied from 132 to 48,040 with a mean of 9556 and increased during the period studied. The overall prevalence across breed and parity groups of DD, IH, SU and WLA was 21%, 6%, 7% and 3%, respectively. The prevalence of the lesions remained quite constant during the 5-year period. DD was recorded in 95% of the herds in 2017. The prevalence of IH, SU and WLA increased with increasing parity. Digital recording of claw lesions may be a good indicator of claw health. However, the recording routines and quality of the recordings must be considered.

A modified functional hoof trimming technique reduces the risk of lameness and hoof lesion prevalence in housed dairy cattle

The objective of this study was to compare the impact of the functional hoof trimming (HT) method to an adaptation that results in increased modelling of the weight bearing claw on time to lameness and lesion prevalence in housed dairy cows. A total of 418 non-lame cows at early and late lactation were enrolled in the study and randomly allocated into 3 groups: functional HT (TRIM1), adaptation method (TRIM2), and an untrimmed group (CON). Locomotion scores (LS; 5-point scale) and animal-based welfare measures were assessed monthly from enrolment until the following 270 days in milk. Cows were considered lame when 2 consecutive LS = 3, or any assessment with a score of 4 or 5. Kaplan-Meier analysis was used to evaluate the difference in time to lameness between the groups. Multivariable CC Cox regression models were fitted to assess associations between covariates and time to lameness event, while associated factors for lesion prevalence were estimated using logistic regression models. The incidence rate of lameness was 29.3 cases/100/month, with corresponding rates of 28.7, 15.8 and 42.8 cases/100/months, in TRIM1, TRIM2 and CON, respectively. Time to first lameness event was higher in TRIM2 (mean ± S.E; 8.26 ± 0.16, P = 0.03) than CON (7.32 ± 0.2) and tended to be higher than TRIM1 (7.83 ± 0.19; P = 0.07). The risk of new lameness event was higher in cows with low BCS (≤2.5) (Hazard ratio; HR = 1.5; 95 % CI 1.1-2.1), while trimming all feet was a protective factor (HR = 0.58; 95 % CI 0.38-0.90). The prevalence of hoof lesions in the study population was 36.3 %, with the highest prevalence in CON (45.6 %), followed by TRIM1 (34.6 %) and TRIM2 (28.1 %). Seventy-eight per cent of hoof lesions were non-infectious and the majority of cows with hoof lesion in TRIM1 (72.3 %), CON (74.6 %) and TRIM2 (55.6 %) were lame. The odds of having a non-infectious hoof lesion were higher in CON (OR = 2.1; 95 % CI 1.2-3.7) compared to TRIM2, and in cows with hock injury (OR = 3.1; 95 % 1.1-9.7) relative to healthy hock, and tended to be higher in cows with low BCS (P = 0.09) relative to those with moderate BCS. Our results suggest that the adaptation to the functional method reduced the risk of lameness during lactation, however, proper management of under-conditioned cows is equally important.

Preventive Hoof Trimming and Animal-Based Welfare Measures Influence the Time to First Lameness Event and Hoof Lesion Prevalence in Dairy Cows

Background: The objectives of this study were to, (1) investigate the impact of the Dutch five-step hoof trimming (HT) technique on time to lameness and hoof lesion prevalence in grazing (GR) and non-grazing (NGR) dairy cows, and (2) determine the association between potential benefits of HT and animal-based welfare measures during lactation. A total of 520 non-lame cows without hoof lesions from 5 dairy farms (GR = 2, NGR = 3) were enrolled at early (within 30 days in milk; DIM) and late lactation (above 200 DIM), and randomly allocated to either trimmed (HGR or HNGR) or control groups (CON-GR and CON-NGR). Locomotion scores, body condition, hock condition, leg hygiene, and hoof health were assessed at monthly intervals until the following 270 days in milk. The data were analyzed using Kaplan-Meier survival analysis, multivariable Cox, and logistic regression models. The overall incidence rate of lameness was 36.2 cases/100 cows/month, with corresponding rates of 27.4, 31.9, 48.4, and 45.8 cases/100 cows/month in HGR, HNGR, CON-GR, and CON-NGR, respectively. Time to first lameness event was significantly higher in HGR (mean ± S.E; 8.12 ± 0.15) compared to CON-GR (7.36 ± 0.26), and in HNGR (8.05 ± 0.16) compared to CON-NGR (7.39 ± 0.23). The prevalence of hoof lesions in the enrolled cows was 36.9%, with a higher occurrence in CON-GR (48.8%) than HGR (23.2%), and in CON-NGR (52.6%) compared to HNGR (32.2%). The majority of hoof lesions were non-infectious in grazing (HGR vs. CON-GR; 21.3 vs. 33.3%) and non-grazing herds (HNGR vs. CON-NGR; 25.0 vs. 40.4%). The risk of lameness was higher in underconditioned cows (Hazard ratio; HR = 3.1, 95% CI 1.2-7.4), presence of hoof lesion (HR = 33.1, 95% CI 17.6-62.5), and there was variation between farms. Aside HT, lower parity (OR = 0.4, 95% CI 0.2-0.8), normal hock condition (OR = 0.06; 95% 0.01-0.29), and absence of overgrown hoof (OR = 0.4; 95% 0.2-0.7) were protective against non-infectious hoof lesions. Functional HT is beneficial as a lameness preventive strategy during lactation; however, ensuring older cows are in good body condition and free from hock injuries are equally important.

A Cross-Sectional Epizootiological Study and Risk Assessment of Foot-Related Lesions and Lameness in Intensive Dairy Sheep Farms

Simple Summary

Foot-related lameness is one of the most significant welfare issues in farm animals. Contrary to dairy cows and meat sheep breeds, epizootiological data on foot-lesions and associated lameness in dairy sheep are scarce. In this study, data were collected from 30 representative intensive dairy sheep farms. Multivariate statistical analysis was used to produce a typology of intensive farming systems which resulted in the assignment of farms in two distinct clusters. Six hundred adult ewes were randomly selected from six flocks (three flocks per cluster) and a cross-sectional study was implemented to investigate the epizootiology and potential risk factors of foot-related lameness, foot-lesions and diseases. Ovine interdigital dermatitis and infectious footrot were the most common infectious foot diseases, while white line disease and hoof wall cracks were the most prevalent non-infectious lesions. Infectious footrot was the main cause of lameness and increased with age, whereas body condition score was associated with increased prevalence of ovine interdigital dermatitis. Comparisons between the clusters regarding foot-related lameness, foot-diseases and lesions at the animal, the limb, and the hoof level are presented, and relevant literature, mechanisms, hypotheses, and challenges of the field are discussed.

Abstract

Foot-related lameness, foot-diseases and lesions are emerging issues in dairy sheep; however, relevant epizootiological studies are scarce, and risk factors have not been elucidated. The objectives of this cross-sectional study were (i) to address this dearth of knowledge by investigating the epizootiology of lameness-related foot-lesions and diseases, and (ii) to assess the impact of potential risk factors on foot health, in intensive dairy sheep farms. Thirty farms were assigned in two representative clusters using a multivariate statistical analysis. Three farms per cluster and 100 multiparous milking ewes per farm (total n = 600) were selected and enrolled in the study. Foot-related lameness, ovine interdigital dermatitis (OID), infectious footrot (IFR), white line disease, hoof wall cracks, as well as health and welfare traits were recorded. Overall prevalence of foot-related lameness was 9.0% and was primarily associated with IFR; however, additional infectious and non-infectious foot diseases and lesions also contributed. Among infectious foot diseases, OID was the most prevalent (21.3%) followed by IFR (8.0%); WLD and hoof wall cracks were the most prevalent non-infectious foot-lesions (37.7% and 15.3%, respectively). IFR and OID prevalence increased with age (p < 0.05) and BCS (p < 0.01), respectively, suggesting that host-related factors and husbandry practices are important determinants of its occurrence.

Association of body condition with lameness in dairy cattle: a single-farm longitudinal study

This research communication describes the relationship between the occurrence of lameness and body condition score (BCS) in a sample of 288 cows from a single farm that were repeatedly scored in the course of 9 months while controlling for confounding variables. The relationship between BCS and lameness was evaluated using generalised linear mixed-effects models. It was found that the proportion of lame cows was higher with decreasing but also with increasing BCS, increased with lactation number and decreased with time since the last claw trimming. This is likely to reflect the importance of sufficient body condition in the prevention of lameness but also raises the question of the impact of overcondition on lameness and the influence of claw trimming events on the assessment of lameness. A stronger focus on BCS might allow improved management of lameness that is still one of the major problems in housed cows.

A Retrospective Case Study into the Effect of Hoof Lesions on the Lying Behaviour of Holstein-Friesian in a Loose-Housed System

Simple Summary

Lameness is a substantial welfare and economic problem in production animals. It can alter indicators of welfare such as lying time. Lying down is very important for cows, and they are highly motivated to perform this behaviour for 12 h or more per day. Conversely, cows that lie down too much or are uncomfortable standing may miss an opportunity to feed or drink if there is competition from sound (non-lame) cows. This study monitored different lesions that cause lameness in cattle through the use of accelerometers. The lesions included sole ulcers, sole haemorrhage, white line disease, interdigital hyperplasia and phelgmon, and digital dermatitis. Leg-based activity monitors that track the cows’ lying behaviour and mobility were used. From these data, it was found that cows with lesions on the foot spent longer lying down than those with no lesions, and cows with lesions in the soft tissue spent less time lying down than those with foot lesions. Trimming the cows’ feet altered the lying times of the cows with foot lesions and returned them closer to those of cows with no lesions.

Abstract

The association between hoof lesions and lying behaviour was assessed on a Holstein–Friesian dairy farm in England. Twenty-nine cows were included in the study. Cows with claw horn disruption lesions (CHDL, n = 8), soft tissue lesions (STL, n = 6), and no lesions (NL, n = 15) were assessed. Data were collected on parity, days in milk (DIM), and mobility scores. Cows were trimmed and treated, and lesions were recorded by a professional foot trimmer. Lying behaviour was assessed before and after claw trimming. The milking herd (n = 96) prevalence of lameness was 32.3%. Mobility was scored using the Agriculture and Horticulture Development Board (AHDB) Mobility Scoring system. Mobility scores were significantly different across lesions groups (p = 0.022). CHDL cows had a mean mobility score of 2.0 ± 0.9 (mean ± SD), STL were scored 1.2 ± 1.3, and NL cows were 0.9 ± 0.7. CHDL were associated with longer lying times (15.00 ± 1.04 h/d; p = 0.0006) and shorter standing times (9.68 ± 2.38 h/d; p = 0.0351) compared with NL lying times (11.77 ± 1.67 h/d) and standing times (12.21 ± 1.67 h/d). STL cows spent significantly less time lying (11.30 ± 2.44; p = 0.0013) than CHDL but not NL cows. No significant differences were found with any of the other lying behaviours. After trimming, CHDL cows spent significantly less time lying down than before trimming (13.66 ± 0.98; p = 0.0125). Cows with NL spent significantly more time lying down (12.57 ± 1.90; p = 0.0398) and had a shorter minimum lying bout duration (0.17 ± 0.09; p = 0.0236) after trimming. In conclusion, lying behaviour in dairy cattle was impacted by type of hoof lesions and hoof trimming.

A history of lameness and low body condition score is associated with reduced digital cushion volume, measured by magnetic resonance imaging, in dairy cattle

Claw horn lesions (CHL) are the result of a failing of the functional anatomy of the hoof in dairy cows. The digital cushion is understood to be a vital structure in the prevention of CHL. Claw horn lesions have previously been shown to lead to pathological change to the pedal bone; however, their effects on the digital cushion are unknown. The primary aim of this study was to examine associations between the history of CHL through an animal's life and the structure of the digital cushion at slaughter using magnetic resonance imaging. The retrospective cohort study resulted in the scanning of 102 pairs of hindfeet, collected from adult Holstein dairy cows culled from a research herd, using a 3-Tesla research-grade magnetic resonance imaging scanner. Volume and fat measurements were calculated for each digital cushion within each claw from a modified Dixon Quant sequence. Animal-level variables were constructed around the animals' lactating lifetime, with lameness scores and body condition score collected at least every 2 wk. The combined volume of digital cushion in the lateral claws was used as the outcome variable in multivariable linear models. The volume of the digital cushion was negatively associated with the number of lameness events or CHL recorded. Furthermore, animals with body condition score >3, culled later in lactation, or of a greater body weight were more likely to have a higher volume of digital cushion in the lateral claws. We propose that the observations made in the current study are the effects of a range of factors broadly associated with genetic, developmental, and disease-related inputs. Our understanding of how we can select for genetically more robust animals and how we can precondition the hoof before first calving needs to be improved to reduce the risk of future CHL in adult dairy cattle. Furthermore, understanding optimal treatment regimens and their effect on hoof anatomy may reduce the recurrence of CHL in the current lactation and future lactations.

Morphology, adipocyte size, and fatty acid analysis of dairy cattle digital cushions, and the effect of body condition score and age

The digital cushion is an essential part of maintaining a healthy foot, working to dissipate foot strike and body weight forces and lameness from claw horn disruption lesions. Despite the importance of the digital cushion, little is known about the basic anatomy, adipocyte morphology, and fatty acid composition in relation to age, limb position, and body condition score. In total, 60 claws (from 17 cows) were selected and collected from a herd, ensuring that body condition score data and computed micro-tomography were known for each animal. Digital cushion tissue underwent histological staining combined with stereology, systematic random sampling, and cell morphology analysis, in addition to lipid extraction followed by fatty acid analysis. The results describe digital cushion architecture and adipocyte sizes. Adipocyte size was similar across all 4 claws (distal left lateral and medial and distal right lateral and medial) and across the ages (aged 2-7 yr); however, animals with body condition score of 3.00 or more at slaughter had a significantly increased cell size in comparison to those with a score of less than 2.50. Of 37 fatty acid methyl esters identified, 5 differed between either the body condition score or different age groups. C10:0 capric acid, C14:0 myristic acid, C15:0 pentadecanoic acid, and C20:0 arachidic acid percentages were all lesser in lower body condition score cows, whereas C22:1n-9 erucic acid measurements were lesser in younger cows. Saturated fatty acid, monounsaturated fatty acid, and polyunsaturated fatty acid percentages were not altered in the different claws, ages, or body condition score groups. Triglyceride quantities did not differ for claw position or age but had decreased quantities in lower body condition score animals. Digital cushion anatomy, cellular morphology, and fatty acid composition have been described in general and also in animals with differing ages, body condition scores, and in the differing claws. Understanding fat deposition, mobilization, and composition are essential in not only understanding the roles that the digital cushion plays but also in preventing disorders and maintaining cattle health and welfare.

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.

The Importance of Low Daily Risk for the Prediction of Treatment Events of Individual Dairy Cows with Sensor Systems

The prediction of health disorders is the goal of many sensor systems in dairy farming. Although mastitis and lameness are the most common health disorders in dairy cows, these diseases or treatments are a rare event related to a single day and cow. A number of studies already developed and evaluated models for classifying cows in need of treatment for mastitis and lameness with machine learning methods, but few have illustrated the effects of the positive predictive value (PPV) on practical application. The objective of this study was to investigate the importance of low-frequency treatments of mastitis or lameness for the applicability of these classification models in practice. Data from three German dairy farms contained animal individual sensor data (milkings, activity, feed intake) and were classified using machine learning models developed in a previous study. Subsequently, different risk criteria (previous treatments, information from milk recording, early lactation) were designed to isolate high-risk groups. Restricting selection to cows with previous mastitis or hoof treatment achieved the highest increase in PPV from 0.07 to 0.20 and 0.15, respectively. However, the known low daily risk of a treatment per cow remains the critical factor that prevents the reduction of daily false-positive alarms to a satisfactory level. Sensor systems should be seen as additional decision-support aid to the farmers’ expert knowledge.

Factors Associated With Lameness in Tie Stall Housed Dairy Cows in South Germany

Lameness remains a major concern for animal welfare and productivity in modern dairy production. Even though a trend toward loose housing systems exists and the public expects livestock to be kept under conditions where freedom of movement and the expression of natural behavior are ensured, restrictive housing systems continue to be the predominant type of housing in some regions. Factors associated with lameness were evaluated by application of multiple logistic regression modeling on data of 1,006 dairy cows from 56 tie stall farms in Bavaria, South Germany. In this population, approximately every fourth cow was lame (24.44% of scored animals). The mean farm level prevalence of lameness was 23.28%. In total, 22 factors were analyzed regarding their association with lameness. A low Body Condition Score (BCS) (OR 1.54 [95%-CI 1.05-2.25]) as well as increasing parity (OR 1.41 [95%-CI 1.29-1.54]) entailed greater odds of lameness. Moreover, higher milk yield (OR 0.98 [95%-CI 0.96-1.00]) and organic farming (OR 0.48 [95%-0.25-0.92]) appeared to be protectively associated with lameness. Cows with hock injuries (OR 2.57 [95%-CI 1.41-4.67]) or with swellings of the ribs (OR 2.55 [95%-CI 1.53-4.23]) had higher odds of lameness. A similar association was observed for the contamination of the lower legs with distinct plaques of manure (OR 1.88 [95%-CI 1.14-3.10]). As a central aspect of tie stall housing, the length of the stalls was associated with lameness; with stalls of medium [(>158-171 cm) (OR 2.15 [95%-CI 1.29-3.58]) and short (≤158 cm) length (OR 4.07 [95%-CI 2.35-7.05]) increasing the odds compared with long stalls (>171 cm). These results can help both gaining knowledge on relevant factors associated with lameness as well as approaching the problem of dairy cow lameness in tie stall operations.

Associations of freestall design and cleanliness with cow lying behavior, hygiene, lameness, and risk of high somatic cell count

The objective of this study was to investigate associations of freestall design and cleanliness with cow lying behavior, hygiene, lameness, and risk of new high somatic cell count (SCC). Cows from 18 commercial freestall dairy herds (22 ± 15 cows/farm; mean ± SD) in Ontario, Canada, were enrolled in a longitudinal study. Four hundred focal cows that were <120 d in milk, had no mastitis treatment in the last 3 mo, and had an SCC <100,000 cells/mL at their most recent milk test were selected for the study. Data on SCC were collected through Dairy Herd Improvement Association milk testing (at ~5-wk intervals). Each farm was visited 5 ± 3 d (mean ± SD) after each milk test until 3 tests were completed (~105 d), for a total of 3 observation periods per cow. Elevated SCC was used as an indicator of subclinical mastitis. An incident of new high SCC was defined as a cow having SCC >200,000 cells/mL at the end of an observation period, when SCC was <100,000 cells/mL at the beginning of that period. Lying behavior was recorded for 6 d after each milk sampling, using electronic data loggers. Cows were scored during each period for lameness (5-point scale, with scores ≥3 = lame), body condition score (BCS; 5-point scale; 1 = thin to 5 = fat), and hygiene (4-point scale). Stall cleanliness was assessed during each period with a 1.20 × 1.65-m metal grid, containing 88 squares. The grid was centered between stall partitions of every tenth stall on each farm, and the squares containing visible urine or fecal matter (or both) were counted. Cow lying time averaged 10.9 ± 1.9 h/d. On average, cows with low BCS (≤2.5) spent 37 ± 16.6 min/d less time lying down than high-BCS cows (≥4.0). On average, cows tended to spend 36 ± 18.3 min/d more time lying down in deep-bedded versus mattress-based stalls. Mean proportion of soiled squares per stall was 20.1 ± 0.50%. Across farms, cow lying time decreased as the proportion of soiled squares per stall increased. A difference in daily lying time of ~80 more min/d was modeled for cows housed in barns with the cleanest stalls compared with those with the dirtiest stalls. Higher neck rail height [for every 1 SD (10 cm) increase] increased the odds (odds ratio = 1.5) of cows having a dirty upper leg-flank and udder. The odds of a cow having a dirty upper leg-flank, udder, and lower legs were 1.5, 2.0, and 1.9 times greater, respectively, for cows housed with dirtier stalls. Also, cows housed on farms with dirtier stalls had 1.3 times greater odds of being lame at the time of observation. Over the study period, 50 new high-SCC cases were detected, resulting in an incidence rate of 0.45 cases of new high SCC per cow-year at risk. No measured factors were detected to be associated with risk of a new high SCC. Overall, our results confirm that cows lie down longer in cleaner and more comfortable environments. Further, these results highlight the need for improved stall cleanliness to optimize lying time and potentially reduce lameness.

Cow- and herd-level factors associated with lameness in dairy farms in Peninsular Malaysia

Lameness is a major welfare issue in dairy cows. This study was aimed at investigating the cow- and herd -level factors associated with lameness in dairy farms from four states in Peninsular Malaysia. The study population was 1001 lactating cows from 28 dairy farms located in Selangor (n = 9), Perak (n = 8), Negeri Sembilan (n = 6) and Johor (n = 5). Lameness was assessed by locomotion scoring. Individual cow characteristics such as breeds, parity, body condition score (BCS), hock condition, leg hygiene, presence of claw lesion and claw overgrowth were recorded. Data on herd characteristics, management practices and housing design were collected by on-farm inspection and farmers' interview. Mixed-eff ;ects logistic regressions were used to model the data and to assess the factors associated with lameness. Cow-level lameness prevalence was 34.2 % (95 % CI 22.2-50.0 %), with all the farms having at least one case of lameness. Claw lesions were recorded in 470 cows (46.9 %; CI 33.3-63.3 %) of which 296 (62.9 %) of them were lame. Of these, 78.9 % of the lesions were present on the rear feet and 25.5% of the cows had more than one foot affected. The proportion of cows having non-infectious and infectious claw lesions were 81.9 % and 18.1 %, and the predominant claw lesions were sole ulcers (24.9 %), white line disease (19.6 %), sole haemorrhage (10.2%), swelling of coronet (9.6 %), toe ulcers (8.4 %), and digital dermatitis (5.6%). Cows at third or more parities had higher odds of lameness (OR = 2.2; 95 % CI 1.2-4.1) compared to primiparous cows. Low BCS (< 2.5) increased the odds of lameness (OR = 4.8; 95 % CI 2.9-7.9) relative to cows with moderate BCS, and cows with hair loss around the hock (OR = 1.4; 95 % CI 1.1-1.9) relative to those with normal hock condition. Greater odds of being lame was observed in cows having claw lesion (OR = 15.2; 95 % CI 10.4-19.2) and those with overgrown claw (OR = 3.3; 95 % CI 2.4-4.5). There was increased odds of lameness in farms with high stocking density (OR = 1.8; 95 % CI 1.1-3.1), concrete floored walkways (OR = 1.9; 95 % CI 1.0-3.6), dirty floors (OR = 2.3; 95 % CI 1.9-3.7), and practicing preventive claw trimming (OR = 2.3; 95 % CI 1.9-4.6). Based on the high lameness prevalence, these findings could assist dairy farmers to make informed decisions on areas to implement on-farm changes to reduce lameness in the studied herds.

Behavior, health, and productivity of early-lactation dairy cows supplemented with molasses in automated milking systems

The objective of this study was to determine the effect of molasses-based liquid feed (LF) supplementation within automated milking systems (AMS) on the behavior, health, and production of early-lactation dairy cows. In 6 commercial AMS dairy herds, 390 dairy cows were randomly assigned before calving to 1 of 2 treatments, within farm, balanced by parity: (1) control group (CON) receiving a standard AMS pellet [mean = 3.9 kg/d on a dry matter (DM) basis, n = 188], or (2) same amount of standard AMS pellet (mean = 3.6 kg/d on a DM basis, n = 202) plus 1 kg/d DM of LF for multiparous cows (1.6 kg/d as fed) and 0.88 kg/d DM for primiparous cows (1.4 kg/d as fed). Across farms, cows were fed partial mixed rations similar in ingredient and nutrient composition. Cows on the LF treatment received supplementation for the first 60 d in milk (DIM). Blood samples were taken 2 times/wk for the first 3 wk postcalving to assess β-hydroxybutyrate (BHB). Samples with BHB ≥1.2 mmol/L were classified as a positive case of subclinical ketosis (SCK). Cow body condition and lameness were scored every 10 d postcalving until 60 DIM. No differences were detected between treatments for milk yield (average milk yield = 37.4 ± 1.98 kg/d) and milking frequency (average milking frequency = 3.2 ± 0.01 times/d). Similarly, no difference between treatments in daily AMS visits was detected (average AMS visits = 5.3 ± 0.3 times/d). However, CON cows experienced more AMS refusals/d than LF cows (LF = 1.6 refusals/d, CON = 2.1 refusals/d). No difference between treatments in daily rumination time was detected (average rumination time = 476 ± 10.8 min/d). Treatment was associated with the number of times cows tested positive for SCK; cows on LF had fewer repeated diagnoses of SCK, such that 15% of cows on LF had ≥3 diagnoses of SCK out of 5 tests, compared with 27% of CON cows. Cows receiving molasses tended to have lower blood BHB values at ∼15 DIM. Molasses supplementation also allowed cows to maintain a more stable body condition score, as LF cows tended to lose less body condition over the first 60 DIM compared with CON cows. Overall, the results of this study demonstrate that supplementing a molasses-based LF to AMS cows may help support the energy demands of milk production in early lactation and, thus, reduce the incidence of repeat positive SCK tests during that time period.

Cow and herd-level risk factors associated with mobility scores in pasture-based dairy cows

Lameness in dairy cows is an area of concern from an economic, environmental and animal welfare point of view. While the potential risk factors associated with suboptimal mobility in non-pasture-based systems are evident throughout the literature, the same information is less abundant for pasture-based systems specifically those coupled with seasonal calving, like those in Ireland. Therefore, the objective of this study was to determine the potential risk factors associated with specific mobility scores (0 = good, 1 = imperfect, 2 = impaired, and 3 = severely impaired mobility) for pasture-based dairy cows. Various cow and herd-level potential risk factors from Irish pasture-based systems were collected and analyzed for their association with suboptimal mobility, whereby a mobility score of 0 refers to cows with optimal mobility and a mobility score ≥ 1 refers to a cow with some form of suboptimal mobility. Combined cow and herd-level statistical models were used to determine the increased or decreased risk for mobility score 1, 2, and 3 (any form of suboptimal mobility) compared to the risk for mobility score 0 (optimal mobility), as the outcome variable and the various potential risk factors at both the cow and herd-level were included as predictor type variables. Cow-level variables included body condition score, milk yield, genetic predicted transmitting ability for 'lameness', somatic cell score, calving month and cow breed. Herd-level variables included various environmental and management practices on farm. These analyses have identified several cow-level potential risk factors (including low body condition score, high milk yield, elevated somatic cell count, stage of lactation, calving month, and certain breed types), as well as various herd-level potential risk factors (including the amount of time taken to complete the milking process, claw trimmer training, farm layout factors and foot bathing practices) which are associated with suboptimal mobility. The results of this study should be considered by farm advisors when advising and implementing a cow/herd health program for dairy cows in pasture-based systems.

Ultrasonographic alterations of bovine claws sole soft tissues associated with claw horn disruption lesions, body condition score and locomotion score in Holstein dairy cows

Claw Horn Disruption Lesions (CHDL) negatively affect the sole soft tissue structures located beneath the sole horn. The aim of the present study was to investigate the effect of CHDL on sole soft tissues by ultrasound means, correlating Body condition score (BCS), locomotion score and CHDL with ultrasonography evaluations of sole soft tissues in Holstein dairy cows. 100 Holstein dairy cows were enrolled in the study. BCS and locomotion score were assessed and functional trimming was performed on all animals. 84 healthy claws and 174 claws with solely one CHDL per claw were evaluated both clinically and with ultrasound, and CHDL were identified and recorded. Sole soft tissues thickness (mm) and echogenicity was determined, and ultrasonographic alterations, related to CHDL presence, where measured long their vertical (L1) and horizontal (L2) axis. Statistically significant (P < .001) differences were found in echogenicity between healthy claws and all the affected ones, with the healthy ones being mainly anechoic. Statistically significant (P < .001) differences were found for vertical (L1) and horizontal (L2) axis measures between the diverse CHDL, confirming ultrasonography as a useful tool to distinguish lesions and their extension by measuring L1 and L2. BCS had an influence both on sole soft tissues ultrasonographic appearance and on CHDL insurgency. These results confirm ultrasonography as a reliable tool for detecting an increase in sole soft tissues echogenicity, that was seen to occur with CHDL insurgency, and in determining lesion extension.

Univariate associations between housing, management, and facility design factors and the prevalence of lameness lesions in fourteen small-scale dairy farms in Northeastern Algeria

Background and Aim:

This cross-sectional study aimed to analyze the associations between different types of housing, management, and facilities on the prevalence of lame, causing lesions in smallholder dairy farms in Algeria.

Materials and Methods:

The on-site investigation took place between December 2012 and May 2015. All cows were locomotion scored on a four-point scale, and foot lesions causing lame were diagnosed and recorded. Factors related to the farm and the cows’ conditions were also assessed. The association between the possible risk factors and lame lesions was assessed using univariate analysis.

Results:

Of the 349 cows evaluated, 13% were lame (lameness score ≥2), with higher lameness values recorded for the hind feet than for the forefeet. Cows without lameness were classified as healthy. The two most frequent lesion diagnoses observed in lame cows were interdigital dermatitis/heel horn erosion (ID/HE; 39%) and interdigital phlegmon (IP; 35%), followed by traumatic lesions (T; 11%), digital dermatitis (DD; 8.7%), and laminitis-related diseases (L; 6.5%). The risk of being lame was increased in large herds with cows of the Holstein breed, and those in the third parity and above. Tie housing, concrete floor, concentrate feeding, zero-grazing, and the use of foot trimming occasionally were associated with increased risk for the presence of lame lesions. The region and footbathing frequency had no association with the prevalence of lame lesions (p≥0.05).

Conclusion:

These results have important implications; they indicate that several aspects of housing, management, and facility design are common protective factors for the prevalence of lame lesions. These factors should be maintained correctly to not only reduce the number of lame cows in these herds but also decrease the direct and indirect costs associated with cases of lameness.

Short communication: Investigation of the temporal relationships between milk mid-infrared predicted biomarkers and lameness events in later lactation

This study reports on the exploration of temporal relationships between milk mid-infrared predicted biomarkers and lameness events. Lameness in dairy cows is an issue that can vary greatly in severity and is of concern for both producers and consumers. Metabolic disorders are often associated with lameness. However, lameness can arise weeks or even months after the metabolic disorder, making the detection of causality difficult. We already use mid-infrared technology to predict major milk components, such as fat or protein, during routine milk recording and for milk payment. It was recently shown that this technology can also be used to predict novel biomarkers linked to metabolic disorders in cows, such as oleic acid (18:1 cis-9), β-hydroxybutyrate, acetone, and citrate in milk. We used these novel biomarkers as proxies for metabolic issues. Other studies have explored the possibility of using mid-infrared spectra to predict metabolic diseases and found it (potentially) usable for indicating classes of metabolic problems. We wanted to explore the possible relationship between mid-infrared-based metabolites and lameness over the course of lactation. In total, data were recorded from 6,292 cows on 161 farms in Austria. Lameness data were recorded between March 2014 and March 2015 and consisted of 37,555 records. Mid-infrared data were recorded between July and December 2014 and consisted of 9,152 records. Our approach consisted of fitting preadjustments to the data using fixed effects, computing pair-wise correlations, and finally applying polynomial smoothing of the correlations for a given biomarker at a certain month in lactation and the lameness events scored on severity scale from sound or non-lame (lameness score of 1) to severely lame (lameness score of 5) throughout the lactation. The final correlations between biomarkers and lameness scores were significant, but not high. However, for the results of the present study, we should not look at the correlations in terms of absolute values, but rather as indicators of a relationship through time. When doing so, we can see that metabolic problems occurring in mo 1 and 3 seem more linked to long-term effects on hoof and leg health than those in mo 2. However, the quantity (only 1 pair-wise correlation exceeded 1,000 observations) and the quality (due to limited data, no separation according to more metabolic-related diseases could be done) of the data should be improved.

Evaluation of postpartum metabolic and health response in dairy cows with different body condition score during the dry period

This study aimed to evaluate the effects of different pre-calving body conditions on some metabolic indices, health status and reproductive disorders in dairy cows. The study was conducted on a dairy farm in Eastern Slovakia during the pre-partum period (–1 to –10 DIM) and post-partum period (1 to 14 DIM). Total of 84 cows allotted in 3 groups were submitted to clinical examination and body condition score (BCS) evaluation. At the same intervals blood samples were collected for determination of beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), and calcium levels. During the postpartum period the incidence of reproductive diseases, such as metritis, retained placenta, metabolic disorders, such as milk fever, left displacement of abomasum and orthopaedic disorders were recorded. The strongest lipid mobilisation (NEFA elevation), ketone body production, and blood calcium drop were determined in postpartum dairy cows with the highest prepartum body condition score. In conclusion, the dairy cows with different BCS hade a different metabolic response during the postpartum period. The overcondition was connected with stronger lipid mobilisation and calcium drop after calving. Moreover, the higher BCS could contribute to higher incidence of production diseases.

Effects of case definition and assessment frequency on lameness incidence estimates

The reliability of locomotion scoring is often low, making it unclear how a single gait score should be interpreted. In addition, differences in assessment frequency between longitudinal studies makes it hard to compare results. Our aims were to evaluate how lameness definition and assessment frequency affect measures of lameness incidence. Six dairy farms in British Columbia, Canada, were enrolled, and 262 cows that were sound at dry-off had their locomotion score (LS) assessed weekly from dry-off to calving, using a 1 to 5 scale. Cows were categorized as remaining sound or becoming lame using 3 different case definitions (LAME1: ≥LS3 at least once; LAME2: ≥2 consecutive scores of LS3, or ≥LS4 at least once; and LAME3: ≥3 consecutive scores of LS3, or ≥LS4 at least once). We analyzed the correspondence between the 3 definitions with percent agreement and weighted κ (linear and quadratic weighting). Comparing LAME1 to LAME3 resulted in lower percent agreement (53%) and κ values (linear κ_w = 0.50; quadratic κ_w = 0.64) than comparing LAME2 and LAME3 (85%; linear κ_w = 0.83; quadratic κ_w = 0.89), indicating that cows scored LS3 twice were likely to be scored LS3 a third time. We also compared the 3 case definitions against trim records from trimmings occurring 90 d or less before calving (n = 117), and used logistic regression models to determine sensitivity, specificity, and positive and negative predictive value. Using the LAME1 criterion resulted in high sensitivity (horn lesions = 0.90; infectious lesions = 0.92) and low specificity (horn = 0.21; infectious = 0.24). We observed higher specificity for LAME2 (horn = 0.62; infectious = 0.66) and LAME3 (horn = 0.71; infectious = 0.77), but LAME2 had higher sensitivity than LAME3 (horn = 0.89 vs. 0.64; infectious = 0.69 vs. 0.64). When evaluating the effects of assessment frequency, we obtained 3 data sets by keeping every, every other, and every third locomotion assessment, and using LAME2 as a case definition. More cows were categorized as lame when assessment frequency increased. Of the cows that were classified as lame when assessed weekly, 72% of the mildly lame, and 33% of the severely lame were classified as sound when assessed every third week. Our results suggest that a single LS3 score should not be used as a criterion for lameness in longitudinal studies. To correctly identify new cases of lameness, dairy cows should be assessed at least every 2 wk.

A systematic review and meta-analyses of risk factors associated with lameness in dairy cows

BACKGROUND

Lameness in dairy cows has been an ongoing concern of great relevance to animal welfare and productivity in modern dairy production. Many studies have examined associations between various factors related to housing, management, and the individual animal and the occurrence of lameness. The objective of this systematic review was to answer the research question "what are risk factors associated with lameness in dairy cows that are housed in free stall barns or tie stall facilities". Furthermore, we performed a synthesis of current evidence on certain risk factors by means of a meta-analysis to illustrate the strength of their association with bovine lameness.

RESULTS

Following pre-defined procedures and inclusion criteria in accordance with the PRISMA statement, two observers independently included 53 articles out of a pool of 1941 articles which had been retrieved by a broad literature research in a first step. 128 factors that have been associated with lameness were identified in those papers. Meta-analyses were conducted for five factors presented in six different studies: Body condition score, presence of claw overgrowth, days in milk, herd size, and parity. Results indicated that a body condition score of ≤2.5/5 is associated with increased odds of lameness. A higher risk of being lame was found for the presence of claw overgrowth, the first 120 days in milk, larger herd sizes, and increasing parity. Throughout the study, we encountered profound difficulties in retrieving data and information of sufficient quality from primary articles as well as in recovering comparable studies.

CONCLUSIONS

We learned that an abundance of literature on bovine lameness exists. To adequately address a problem of this importance to both animal welfare and economic viability, solid evidence is required in the future to develop effective intervention strategies. Therefore, a consistent working definition of lameness and specific risk factors should be an option to consider.

Factors associated with lameness prevalence in lactating cows housed in freestall and compost-bedded pack dairy farms in southern Brazil

The aim of this cross-sectional study was to investigate factors associated with lameness in dairy cows on intensive farms in southern Brazil. Farms (freestall: n = 38; compost-bedded pack: n = 12) having on average 274 (range: 41-901) lactating cows were visited once in 2016 (March to October). Potential risk factors for lameness at the cow, pen and herd levels were investigated through inspection of facilities, examination of cows and the use of data collected on routine management practices. All milking cows on each farm were assessed for gait score and BCS (n = 13,716). Associations between lameness, days in milk (DIM), BCS, parity, and test-day milk yield were investigated in 16 farms with available data (n = 5,301 cows). Mixed-effects linear and logistic regressions were used to model the data. Within-herd lameness prevalence was 41.1% (range: 13.8-64.5, SD = 11.3). First- and second-lactation cows after 120 DIM and older cows after 335 DIM were more likely to be observed lame than early lactation cows. Greater parity and low BCS (≤ 2.75) were associated with increased odds of lameness. Severely lame cows had lower milk yield (on average 1.3 kg/d) than non-lame cows. Freestall dairies using mattresses as stall base had greater within-pen (95% CI: 52-69%) and herd-level (38-57%) lameness prevalence than compost-bedded farms. Higher lameness prevalence was observed on farms having slippery feed bunk alley floors (32-49%) and shortened dry periods (< 60 days: 32-42%). First-lactation pens had lower predicted within-pen lameness prevalence (0-4%) and special-needs pens higher (52-73%) compared with the prevalence observed in compost-bedded fresh-cow pens (19-41%). Freestall pens using sawdust deep-bedding had greater (46-68%) within-pen lameness prevalence, but the prevalence in barns using sand was not different from compost-bedded farms. Given the high lameness prevalence observed in this study, there is a great opportunity for implementation of lameness prevention programs. Providing walking surfaces with high traction that facilitates mobility and using soft and deep-bedded material, such as compost and sand (and avoiding the use of mattresses) may reduce lameness prevalence in the types of dairy farms visited in this study.

Risk factors associated with lameness and hoof lesions in pasture-based dairy cattle systems in southeast Brazil

Cattle lameness is an important welfare concern that also has an economic impact on the dairy industry. It can be a significant problem among pasture-based herds. Our objectives were to identify cow- and herd-level factors related to lameness and hoof lesions in dairy cows grazing year-round in Minas Gerais, Brazil. We performed a cross-sectional study in 48 pasture-based dairy herds, visiting each farm in a single visit. We evaluated 2,262 cows for mobility score (0-3) and 392 cows for hoof lesions. We used a questionnaire and checklist to capture herd management data. All information obtained was used to build multivariable models. The factors associated with lameness were low body condition score, longer time spent in the corral, being kept in paddocks during the drought period, and poor hygiene. For hoof lesions, track features were the most significant factor in determining the likelihood of heel horn erosion, white line fissure, and sole hemorrhage-by more than 3 times. Different factors related to unhygienic conditions such as leg cleanliness, frequency of cleaning, and longer time spent in the corral were associated with infectious hoof lesions. Poor human-animal relationship was related to sole hemorrhage, but patient handling of cows on the track was a protective factor against interdigital hyperplasia. The results of this study suggest that improving hygiene conditions, track features, and cow handling can improve dairy cattle mobility scores in pasture-based farms under tropical conditions. These findings also represent a first step toward planning actions aimed at decreasing lameness and hoof lesions in the studied region.

Associating cow characteristics with mobility scores in pasture-based dairy cows

The quality of dairy cow mobility can have significant welfare, economic, and environmental consequences that have yet to be extensively quantified for pasture-based systems. The objective of this study was to characterize mobility quality by examining associations between specific mobility scores, claw disorders (both the type and severity), body condition score (BCS), and cow parity. Data were collected for 6,927 cows from 52 pasture-based dairy herds, including mobility score (0 = optimal mobility; 1, 2, or 3 = increasing severities of suboptimal mobility), claw disorder type and severity, BCS, and cow parity. Multinomial logistic regression was used for analysis. The outcome variable was mobility score, and the predictor variables were BCS, type and severity of claw disorders, and cow parity. Three models were run, each with 1 reference category (mobility score 0, 1, or 2). Each model also included claw disorders (overgrown claw, sole hemorrhage, white line disease, sole ulcer, and digital dermatitis), BCS, and cow parity as predictor variables. The presence of most types of claw disorders had odds ratios >1, indicating an increased likelihood of a cow having suboptimal mobility. Low BCS (BCS <3.00) was associated with an increased risk of a cow having suboptimal mobility, and relatively higher parity was also associated with an increased risk of suboptimal mobility. These results confirm an association between claw disorders, BCS, cow parity, and dairy cow mobility score. Therefore, mobility score should be routinely practiced to identify cows with slight deviations from the optimal mobility pattern and to take preventive measures to keep the problem from worsening.

Lameness in Sheltered Cows and Its Association with Cow and Shelter Attributes

Simple Summary

The sheltering of cows in shelters is a traditional practice in India. Old, abandoned and unproductive dairy cows are housed in shelters as cow slaughter is not legally permitted in most states. The welfare assessment of these old, abandoned, infertile, unproductive and rescued cows was carried out based on the measurement of cow-based and resource-based welfare parameters. The aim of this cross-sectional study was to explore the prevalence of lameness in these sheltered cows and the risk factors associated with it. Fifty-four shelters in six states of India were visited and 1620 cows were clinically examined for lameness and measurements of other animal and resource-based welfare parameters. The prevalence of lameness in these shelters was less than that recorded in dairy cows in conventional Indian farming systems. Lameness was associated with several cow factors: inadequate body conformation, lesions on the hock and carpal joints, dirty udders, overgrown claws and diarrhea. There was evidence of an association with an absence of bedding and a steep gradient of the floor. Improvement in the feeding practices, attention towards cleanliness, and improvements in shelter flooring may reduce the prevalence of lameness and improve cow welfare in the shelters.

Abstract

The sheltering of old, unproductive and abandoned cows in traditional cow shelters, known as gaushalas, has been practiced in India since ancient times. Cows are kept in these shelters until they die of natural causes. The welfare of the cows in these shelters was assessed through a cross-sectional study of 54 cow shelters in six states of India. A total of 1620 cows were examined to assess the prevalence of lameness in these cows, and the associated risk factors for lameness were identified through the measurement of animal-based and resource-based welfare indicators. The overall lameness prevalence was 4.2%. The majority (86%) had mild to moderate hock joint swellings but no or only mild carpal joint injuries. Approximately one-half had mild to moderate hock joint hair loss and most were free of hock joint ulcerations. Claw overgrowth was present in almost one half of the cows. Lameness prevalence was positively correlated with coat dirtiness, hock and carpal joint lesions, diarrhea and claw overgrowth scores. In a multivariate analysis, lameness prevalence increased as the Body Condition Score (BCS) decreased and was associated with increased udder dirtiness, the ulceration of the hock joint, carpal joint injuries and claw overgrowth. Resource-based indicators measured at the shelter level suggested that an absence of bedding in the sheds and an increase in the gradient of the shed flooring increased lameness. Addressing the principle risk factors identified for lameness in the sheltered cows (low body condition, dirty udders, lesions on the hock and carpal joints, overgrown claws, and a steep floor gradient) may help to reduce this serious animal welfare problem.