Assessment of the welfare of dairy cattle using animal-based measurements: direct observations and investigation of farm records

Recognition of lameness and decisions to catch for inspection among sheep farmers and specialists in GB

Background

Epidemiological studies have used farmer estimates of the prevalence of lameness in their flocks. This assumes that farmers can identify lame sheep. Eight movie clips of sheep with locomotion from sound to moderately lame were used to investigate the ability of farmers and sheep specialists to recognise lame sheep. Each participant was asked to complete a form and indicate, for each movie clip, whether they thought the sheep was lame and whether they would catch it if it was the only lame sheep or if 2 – 5, 6 – 10 or > 10 sheep were equally lame. The farmers' responses were compared with their estimates of flock lameness prevalence and the interval between observing a lame sheep and catching it.

Results

178 farmers and 54 sheep specialists participated. Participants could identify even mildly lame sheep but made a separate decision on whether to catch them. This decision was dependent on the severity of lameness and the number of sheep lame in a group. Those who said they would catch the first lame sheep in a group were significantly more likely to catch mildly lame sheep (farmer-reported median prevalence of lameness 5% (IQR: 2%–6%)). In contrast, farmers who waited for several sheep to be lame indicated that they would only catch more severely lame sheep (farmer reported median flock lameness 11% (IQR: 9%–15%)). Approximately 15% of farmers did not catch individual lame sheep (farmer reported median flock lameness 15% (IQR: 10%–15%)). The flock prevalence of lameness increased as time to treatment increased and time to treatment was positively correlated with only catching more severely lame sheep.

Conclusion

If movie-clips are similar to the flock situation, farmers and specialists can recognise even mildly lame sheep but vary in their management from prompt treatment of the first lame sheep in a group to no individual sheep treatments. The former practices would be appropriate to minimise transmission of footrot, a common, infectious cause of lameness and so reduce its incidence. The analysis also suggests that farmers estimate lameness prevalence relatively accurately because farmers who treated the first mildly lame sheep in a group also reported the lowest prevalence of lameness in their flock.

The development, implementation and testing of a lameness control programme based on HACCP principles and designed for heifers on dairy farms

This paper describes the development and testing of a lameness control programme (LCP) for heifers on dairy farms. The LCP, which is based on the analysis of hazards and critical control points (HACCP), was tested via a randomised intervention study on 60 farms. Tangible hazards for each farm were identified, allotted to 11 categories of proximate hazard and scored on each farm to quantify the risks presented by each hazard. Feet were inspected for signs of claw horn disease and infection, such as digital dermatitis. Intervention was generally ineffective, primarily through failure to implement the LCP. However, retrospective analysis was able to demonstrate highly significant associations between risks attached to proximate hazards and probabilities of lameness and foot lesions, allowing the severity of these hazards to be ranked. The most significant proximate hazards of environmental origin were prolonged standing on concrete, standing in wet slurry and factors that cause claw trauma. The most severe proximate hazards however were those associated with failures of management, especially poor claw condition and inadequate foot care. Overall farm risks (OFR) were estimated by summing the products of the generic severity for proximate hazards with on-farm risks. Changes in OFR were significantly related to changes in outcome (lameness and lesions).

Visual Locomotion Scoring in the First Seventy Days in Milk: Impact on Pregnancy and Survival

Our hypotheses were that cows classified as lame during the first 70 d in milk have more days from calving to conception and a greater hazard of dying or being culled compared with cows that were not classified as lame. Our objective was to estimate the detrimental effects of lameness on calving-to-conception interval and hazard of dying or being culled in lactating Holstein cows. Data were collected from 5 dairy farms located in upstate New York from November 2004 to June 2006. The design was a prospective observational cohort study. Cows were assigned a visual locomotion score (VLS) using a 5-point scale: 1 = normal, 2 = presence of a slightly asymmetric gait, 3 = the cow clearly favored 1 or more limbs (moderately lame), 4 = severely lame, to 5 = extremely lame (nonweight-bearing lame). In total 1,799 cows were enrolled. In 2 alternative categorizations, cows were considered lame if at least 1 VLS was > or =3 during the first 70 d in milk, and if at least 1 VLS was > or =4 for the same period they were considered lame. Lameness (VLS > or =3) was detected at least once in 26.5, 54.2, 33.9, 51.8, and 39.3% of all cows in farms 1 to 5, respectively. The hazard ratio of being detected pregnant was 0.85 for lame cows (VLS > or =3) vs. nonlame cows; hence, lame cows were at a 15% lower risk of pregnancy than nonlame cows. When lameness was redefined as VLS > or =4, the hazard ratio of been detected pregnant was 0.76 for lame cows vs. cows with VLS <4. Lameness increased the hazard ratio of culling/death, 1.45 and 1.74 for VLS > or =3 and VLS > or =4, respectively, vs. cows with VLS <3 and VLS <4, respectively. In summary, lameness significantly decreased the hazard of pregnancy and increased the hazard of culling/death. The detrimental effects were amplified when considering only severely lame and non-weight-bearing cows.

Effects of housing, parturition and diet change on the biochemistry and biomechanics of the support structures of the hoof of dairy heifers

This study investigated effects of housing, diet and parturition on the biochemistry, biomechanics and pathology of feet of maiden, pregnant and lactating dairy heifers. Strength/laxity, laminar morphology, connective tissue (CT) biochemistry and sole lesions were assessed. Although no animals became clinically lame, severity of sole lesions was significantly greater in heifers housed in cubicles vs. straw yards, and in lactating/pregnant heifers vs. maidens. These effects were additive. Cubicle housing and parturition each increased CT metabolism (and were additive), and altered CT composition. Similarly, both impaired the biomechanical resilience of the hoof. There were no effects for diet. The results indicate that parturition/lactation causes non-inflammatory changes in CT that impair resilience of the feet to external stresses associated with poor housing. This "parturition effect" appears to be unrelated to change in diet and relatively brief, unless exacerbated by additional stresses of housing. Thus heifer lameness may be significantly reduced through short-term, low-cost improvements in husbandry around the time of calving.

Association Between a Visual and an Automated Locomotion Score in Lactating Holstein Cows

Two studies were conducted to evaluate visual locomotion scoring (VLS) and Stepmetrix locomotion scoring (SLS) in detecting painful digit lesions. In study 1, one veterinarian performed VLS. Cows with VLS > or = 3 were hoof trimmed and the presence or absence of a painful lesion (PL), defined as a reaction to digital pressure, was recorded. A strongly increasing pattern in the proportion of cows with PL was detected as VLS increased. The proportions of cows with painful lesions were 5.6% (n = 53), 20.1% (n = 78), 55.5% (n = 164), 79.9% (n = 159), and 100% (n = 5) for VLS 1 to 5, respectively. Study 2 was conducted on a different farm. The entire farm was visually locomotion scored by 3 veterinarians on the same day, and the cows were Stepmetrix locomotion scored by walking through the Stepmetrix system. Every cow was trimmed during the following 2 d by 1 of 8 professional hoof trimmers. The 3 veterinarians identified, scored, and recorded any PL. Interobserver agreement for the 3 veterinarians had a kappa coefficient of between 0.45 and 0.48 +/- 0.05. In total, 518 cows were used in the analysis, from which 11.2% were identified with a PL. Of the cows diagnosed with a PL, 32.8% were detected with a sole ulcer, 25.9% with white line disease, 13.8% with white line abscess, and 27.5% with other diseases. A receiver operating characteristic analysis was performed; the area under the curve was larger for VLS (0.80; 95% confidence interval, 0.76 to 0.83) than SLS (0.62; 95% confidence interval, 0.57 to 0.66). When performed by trained veterinarians, VLS performed better than SLS in detecting PL.

Is quality of life a useful concept for companion animals?

Although the term ‘quality of life’ (QoL) is not unfamiliar to veterinary surgeons, only recently has the scientific community attempted to measure it in farm and companion animals. Typically such studies have applied methodologies from the field of human health-related quality of life (HRQoL), without due consideration of the applicability of both the term and its measurement to animals. However, it is necessary to clarify the philosophical basis of QoL if it is to be defended as a rigorous and reliable aid to decision-making in animal welfare science. In this paper we review common concepts in human HRQoL and discuss the value of, and difficulties regarding, the transfer of the concept of human HRQoL to companion animals. Human definitions tend to focus on individuals and their assessment of the state of their life in terms of physical, social and psychological functioning. The use of the term ‘quality of life’ for animals may therefore expand on what is usually considered when using the term ‘welfare’, and thereby improve on current practice, which tends to focus on relatively few outcome measures that are largely indicative of poor welfare. However, failure in the human literature to properly define QoL and defend the choice of measures accordingly, together with the common use of objective indicators and proxies, has led to confusion over the relative roles of objective and subjective measures in the determination and constitution of QoL. A suggestion for an appropriate definition of animal QoL that clarifies these relationships is offered, together with a list of social/environmental and physical/psychological health-related domains that may be suitable for a generic companion animal QoL assessment tool. In the absence of knowledge on both basic needs and individual preferences, particularly for institutionalised animals, QoL tools may be more appropriately designed as outcome-based tools, focussing on observable signs of health and behaviour. The extent to which recent QoL assessment tools for companion animals have covered these domains, and the extent to which the psychometric properties of the tools have been addressed, is also briefly discussed.

Welfare assessment on Japanese dairy farms using the Animal Needs Index

The Animal Needs Index (ANI) is used for on-farm assessment of welfare in Austria. However, no synthetic welfare assessment system exists in Japan. We performed a welfare assessment of Japanese dairy farms using the ANI scoring system. On 25 farms, 36 dairy herds were assessed using the ANI35L/2000-cattle survey. On 10 dairy farms, 16 herds were housed in free-stall barns. The other 20 herds of 15 dairy farms were housed in tie-stall barns. This study was conducted between December 2004 and January 2005. The ANI scores ranged from 6.0 to 40.0 points (mean 17.8 points). The four high ranking herds on ANI value were housed in free-stalls and allowed the use of outside areas. The 13 low ranking herds were housed in tie-stalls and were not allowed the use of outside areas. The free-stall herds had significantly higher ANI scores than tie-stall herds. The ANI scores of herds having access to outside areas were significantly higher than those of herds having no outside access. This scoring system might be useful for Japanese dairy farms. However, some assessment parameters contain subjective criteria such as cleanliness, floor slipperiness, and animal health. Further studies are necessary to improve the scoring system, in particular clarifying criteria related to those parameters.

Formal animal-based welfare assessment in UK certification schemes

Providing assurance of improvement in welfare outcomes is the desire of some UK certification schemes. However, this is only likely to be achieved if such schemes monitor welfare outcomes rather than rely on defining welfare resources that should be provided. The University of Bristol has developed protocols for the on-farm evaluation of animal-based welfare parameters for incorporation into certification schemes. The assessment system is designed to provide credible (repeatable, valid and feasible) evidence for assessment of compliance with welfare standards in organic and conventional farming systems. For issues identified as causing potential concern the assessor is encouraged to conduct further investigations of the relevant resource standards and, where appropriate, management requirements. Furthermore the assessment tool enables certification bodies and relevant third parties to monitor the ability of schemes to deliver good welfare outcomes. Finally, it provides a mechanism for farmers to review their own health and welfare performance. The practical application of these systems is now being pursued by some UK certification bodies.

Normal behaviour as a basis for animal welfare assessment

It is generally agreed that farm animal welfare is at a high level when the animals can behave naturally. Most of today's housing systems, however, differ considerably from the natural environment in which the behavioural organisation of the ancestors of our farm animal species evolved. Consequently, normal behaviour may be impaired in several ways. Frequency, duration or sequence of behavioural elements may be affected. Some normal behaviour patterns may not occur at all. The animals may also possibly behave in unnatural ways – in patterns that would never occur in nature. Furthermore, it is usual for farm animals to exhibit behaviour which is normal in form, but which is elicited by artificial structures within their housing system.

In view of these possible changes in normal behaviour, it is necessary to assess, for each farm animal species and each housing system, whether animal welfare is at risk in any way if the behaviour observed differs from the behaviour that would occur in a natural environment. In some cases the question can be answered by taking a theoretical evolutionary approach. In most cases, however, detailed knowledge about the behavioural organisation of the animals is necessary. Such knowledge is built up from animal motivation studies and investigations into the effect of environmental structures on animal behaviour.

A specific problem of on-farm animal welfare assessment is that there is often not enough time to collect sufficient data to make a judgement about the occurrence of normal behaviour. Resource-based assessment methods are appropriate as an alternative, provided that the resource standards used are based on evidence stemming from research into animal behaviour and motivation.

A Probabilistic Neural Network Model for Lameness Detection

A 4-balance system for measuring the leg-load distribution of dairy cows during milking to detect lameness was developed. Leg weights of 73 cows were successfully recorded during almost 10,000 robotic milkings over a period of 5 mo. Cows were scored weekly for locomotion, and lame cows were inspected clinically for hoof lesions. Unsuccessful measurements, caused by cows standing outside the balances, were removed from the data with a special algorithm, and the mean leg loads and number of kicks during milking were calculated. To develop an expert system to automatically detect lameness cases, a model was needed, and a classifying probabilistic neural network model was chosen for the task. The data were divided into 2 parts and 5,074 measurements from 37 cows were used to train a classifying probabilistic neural network model. The operation of the model was evaluated for its ability to detect lameness in the validating data set, which had 4,868 measurements from 36 cows. The model was able to classify 96.2% of the measurements correctly as sound or lame cows, and 100% of the lameness cases in the validation data were identified. The number of measurements (equal to the number of milkings) causing false alarms was 1.1%. The model developed has the potential to be used as an on-farm decision aid and can be used in a real-time lameness monitoring system.

The journey to animal welfare improvement

The process of driving improvement in animal welfare has three stages: 1) assessment of animal welfare, 2) identification of the risk factors potentially leading to a compromise in animal welfare, and 3) interventions, in response to the risk factors, to bring about improvement in animal welfare. This process is applicable to animals farmed in commercial situations and for individual animals kept or worked in isolated environments. An impressive weight of knowledge has accumulated in the science of animal welfare assessment and this needs to be counterbalanced by development of mechanisms to actively improve welfare. In the case of animal welfare, interventions have to motivate the animal owner or carer to make changes to their own behaviour on behalf of a third party; the animal. This is a different situation from that described in the human health literature where interventions encourage people to take steps to improve their own well-being, thus benefiting themselves directly. The development of strategies to improve animal welfare require a multi-disciplinary approach including social scientists, psychologists and economists, however, the skills of animal welfare scientists are essential to ensure that interventions truly achieve improvements in animal welfare.

Promoting quality of life discussions between the veterinary profession and the pet-owning public

Because it is the pet-owning public that normally provides the day-to-day care for companion animals, maintaining or improving standards in animal welfare is best achieved by engaging owners in the debate over an individual animal's quality of life (QoL). Veterinary practice teams (including veterinary surgeons and nurses) are in an ideal position to promote discussion of pets' QoL, as most owners respect and value their opinion. As well as educating each new generation of animal carers on appropriate husbandry, the veterinary profession can engage the pet-owning public in the scientific process of QoL assessment and the related debates concerning definitions of welfare and QoL. QoL assessment is a complex process with many influencing factors. The structure of an assessment will depend upon its purpose, which may be research, legislation, a certification scheme or, probably most usefully, a management tool to facilitate clinical decision-making. The process of completing a QoL assessment within a clinical environment may result in positive changes in human behaviour towards animals irrespective of the actual result of the assessment. This influence on human behaviour is a key test of validity for formal assessment systems that are designed to improve QoL.

Dairy cow cleanliness and milk quality on organic and conventional farms in the UK

A subjective cow cleanliness scoring system was validated and used to assess the cleanliness score of dairy cows at different times in the year. A longitudinal study followed a number of farms from summer to winter, and a larger, cross-sectional study assessed a greater number of farms during the housed winter period. The scoring system was demonstrated to be both a repeatable and practical technique to use on-farm and showed that cows become dirtier in the transition from summer grazing to winter housing. Although farming system (organic or conventional) had no effect on cow cleanliness when cows were at grass, when housed in the winter, organic cows were significantly more likely to be cleaner. There was a link between cow cleanliness scores and milk quality, with herds having lower bulk tank somatic cell counts (BTSCC) tending to have a lower (cleaner) median cow cleanliness score; with this relationship strongest for the organic herds. There was no significant link between cleanliness score and Bactoscan (BS) count or clinical mastitis incidence. No major mastitis pathogens were cultured from bulk tank milk samples from the quartile of herds with the cleanest cows in contrast to the quartile of herds with the dirtiest cows, where significant mastitis pathogens were cultured. Based on this study, all farms, especially organic systems, should attempt to keep cows clean as part of subclinical mastitis control.

Housing System, Milk Production, and Zero-Grazing Effects on Lameness and Leg Injury in Dairy Cows

The aim of this study was to assess the effect of grazing (G) vs. zero-grazing (ZG), level of milk production, and quality and type of housing system [free stalls (FS) and straw yards (SY)] on the prevalence of lameness and leg injuries in dairy cows. Observations were made on 37 commercial dairy farms across Great Britain. A single visit of 5 d duration was made to each farm. During this visit, lameness scores and the incidence of swellings, rubs, and injuries to hocks and knees were recorded on all the peak- or mid-lactation cows. Aspects of the quality of housing and management that were likely to affect foot and leg health were recorded. There were more lame cows on ZG farms (39 +/- 0.02%) than on grazing (G) farms (15 +/- 0.01%), and lameness scores were higher on FS farms compared with SY farms (0.25 +/- 0.01 vs. 0.05 +/- 0.01). Cows on SY farms had fewer hock and knee injuries compared with FS farms. The frequency of knee swellings was higher on ZG farms (0.31 +/- 0.02) than on G farms (0.15 +/- 0.01). Aspects of the free-stall design affected foot and leg health. The number of hock swellings increased with increasing stall gradient (0.16 +/- 0.01 with no slope vs. 0.39 +/- 0.02 at a 0 to 1.5% slope). There was an interaction between the length of the free-stall lunging space and the hip width of the cow, indicating that the incidence of lameness is generally highest on farms with small free stalls and heavy cows. High levels of milk production did not affect lameness or leg injury. The results indicate that housing cows throughout the year potentially has a detrimental effect on foot and leg health. However, good free-stall design may reduce lameness and leg lesions.

Comparison of Models to Identify Lame Cows Based on Gait and Lesion Scores, and Limb Movement Variables

Bovine lameness results in pain and suffering in cattle and economic loss for producers. A system for automatically detecting lame cows was developed recently that measures vertical force components attributable to individual limbs. These measurements can be used to calculate a number of limb movement variables. The objective of this investigation was to explore whether gait scores, lesion scores, or combined gait and lesion scores were more effectively captured by a set of 5 limb movement variables. A set of 700 hind limb examinations was used to create gait-based, lesion-based, and combined (gait- and lesion-based) models. Logistic regression models were constructed using 1, 2, or 3 d of measurements. Resulting models were tested on cows not used in modeling. The accuracy of lesion-score models was superior to that of gait-score models; lesion-based models generated greater values of areas under the receiving operating characteristic curves (range 0.75 to 0.84) and lower mean-squared errors (0.13 to 0.16) compared with corresponding values for the gait-based models (0.63 to 0.73 and 0.26 to 0.31 for receiving operating characteristic and mean-squared errors, respectively). These results indicate that further model development and investigation could generate automated and objective methods of lameness detection in dairy cattle.

An Evaluation of the Seasonality of Veterinary Treatments for Lameness in UK Dairy Cattle

Of the 4 main diseases causing lameness in UK dairy cattle, 2 (digital dermatitis and foul-in-the-foot, or interdigital necrobacillosis) are infectious diseases that are commonly associated with similar underfoot conditions, and 2 (sole ulcer and white-line disease) result from subclinical laminitis. Comparison of the seasonality of these 2 diseases can identify whether their own unique risk factors are more important than the risk factors they share. Using a database from 46 veterinarians distributed across the United Kingdom, the seasonality of treatments for these 4 diseases was evaluated. This analysis showed that the seasonality of lameness in UK dairy cattle was significantly reduced in comparison with previous reports from the 1980s. This was primarily due to 1) a reduction in the seasonality of digital dermatitis (outbreaks of which accounted for 6.7% of veterinary reports), with only 60% of reports during the winter as opposed to 72% in earlier studies, and 2) a change in the seasonality of white-line disease from a disease that was most commonly seen in the winter (55% of reports) to a disease that was most commonly reported in the late summer or early autumn, with significantly more reports in August and October than in February. Comparison of the seasonality of digital dermatitis and foul-in-the-foot showed a significant difference in the seasonality of the 2 diseases, with foul-in-the-foot being significantly more common compared with digital dermatitis in June and August. This implies that significant risk factors exist for digital dermatitis that are not as important for foul-in-the-foot. The difference in the seasonality of sole ulcer and white-line disease was even more marked, with white-line disease being significantly more common than sole ulcer from August to October, despite these diseases being more closely linked in the literature than digital dermatitis and foul-in-the-foot. This comparison shows that the seasonality of lameness has changed in the United Kingdom and that white-line disease has significantly different risk factors than sole ulcer.

Prevalence of Lameness in High-Producing Holstein Cows Housed in Freestall Barns in Minnesota

A cross-sectional study was conducted to estimate the prevalence of clinical lameness in high-producing Holstein cows housed in 50 freestall barns in Minnesota during summer. Locomotion and body condition scoring were performed on a total of 5,626 cows in 53 high-production groups. Cow records were collected from the nearest Dairy Herd Improvement Association test date, and herd characteristics were collected at the time of the visit. The mean prevalence of clinical lameness (proportion of cows with locomotion score >or=3 on a 1-to-5 scale, where 1 = normal and 5 = severely lame), and its association with lactation number, month of lactation, body condition score, and type of stall surface were evaluated. The mean prevalence of clinical lameness was 24.6%, which was 3.1 times greater, on average, than the prevalence estimated by the herd managers on each farm. The prevalence of lameness in first-lactation cows was 12.8% and prevalence increased on average at a rate of 8 percentage units per lactation. There was no association between the mean prevalence of clinical lameness and month of lactation (for months 1 to 10). Underconditioned cows had a higher prevalence of clinical lameness than normal or overconditioned cows. The prevalence of lameness was lower in freestall herds with sand stalls (17.1%) than in freestall herds with mattress stall surfaces (27.9%). Data indicate that the best 10th percentile of dairy farms had a mean prevalence of lameness of 5.4% with only 1.47% of cows with locomotion score = 4 and no cows with locomotion score = 5.

Hoof Discomfort Changes How Dairy Cattle Distribute Their Body Weight

Lameness is a costly and widespread health and welfare problem in intensive dairy production, and reliable automated methods to detect lameness are needed. Lameness may be detected through the measurement of how cattle distribute their weight among their 4 legs, but this requires an understanding of how cattle redistribute their weight in response to pain in one or more limbs. In 3 experiments, 13, 12, and 15 Holstein dairy cows were trained to stand on a platform that measured the weight placed on each limb. We replaced the soft rubber surface under either 1 or 2 hooves with an uncomfortable concrete surface. Cows placed less weight on a back hoof that was placed on an uncomfortable surface, and they redistributed the majority of the weight onto the contralateral back hoof but did not change the distribution of weight on their front hooves. When the same surface was placed under a front hoof, cows placed less weight on that hoof and placed more weight on the contralateral front hoof and the ipsilateral back hoof. The variation in weight the cow placed on both contralateral hooves increased when one of the hooves was on the uncomfortable surface. Cows placed more weight on the back hooves when both front hooves were standing on uncomfortable surfaces, although no change was observed when back hooves were on uncomfortable surfaces. Dairy cows remove weight from a limb in response to limb discomfort and redistribute this weight primarily to the contralateral limb. The variation in weight over time applied to a pair of contralateral limbs increases in response to discomfort in one hoof. Cows have only limited ability to shift weight from front to back. Measures of weight distribution may provide useful on-farm techniques for the detection of lameness.

Effect of Hoof Pathologies on Subjective Assessments of Dairy Cow Gait

To explore how hoof pathologies affect dairy cattle gait, we studied cows with sole hemorrhages (n = 14), sole ulcers (n = 7), and those with no visible injuries (n = 17). Overall gait assessments, scored from video using a 1 to 5 numerical rating system (1 = sound, 5 = severely lame) and a continuous 100-unit visual analog scale, found cows having sole ulcers had poorer gait than healthy cows (mean +/- SEM: 4.0 +/- 0.13 vs. 3.1 +/- 0.08, and 59 +/- 3 vs. 46 +/- 2, respectively). Six gait attributes (back arch, head bob, tracking-up, joint flexion, asymmetric gait, and reluctance to bear weight) were also assessed using continuous 100-unit scales. Compared with healthy cows, those having sole ulcers walked with a more pronounced back arch (12 +/- 3 vs. 28 +/- 4), more jerky head movement (2 +/- 2 vs. 10 +/- 3), shortened strides (7 +/- 2 vs. 26 +/- 4), and more uneven weighting among the limbs (16 +/- 2 vs. 32 +/- 3). Of all measures, the numerical rating system most effectively discriminated healthy cows from those with sole ulcers (R2 = 0.73), classifying 92% of animals correctly. No differences were detected among cows with and without sole hemorrhages. Intra- and interobserver reliabilities were reasonable for all measures (R2 > or = 0.64) except joint flexion and asymmetric gait. In summary, subjective assessments of dairy cattle gait provide valid and reliable approaches to identifying cattle with sole ulcers.

Assessment of the welfare of working horses, mules and donkeys, using health and behaviour parameters

Working animals provide an essential transport resource in developing countries worldwide. Many of these animals are owned by poor people and work in harsh environments, so their welfare is a cause for concern. A protocol was developed to assess the welfare of working horses, mules and donkeys in urban and peri-urban areas, using direct observation of health and behaviour parameters. In this study, 4903 animals used for draught, pack and ridden work in Afghanistan, Egypt, India, Jordan and Pakistan were assessed between December 2002 and April 2003. The data showed that donkeys were more likely than mules or horses to demonstrate avoidance or aggressive behaviour towards an observer, while horses were most likely to make a friendly approach. Fewer than 8% of working equines had abnormal mucous membranes, ectoparasites or poor coat condition. Body lesions occurred predominantly in the areas of the breast/shoulder, withers and girth in all three species, with mules having the highest prevalence of lesions in these areas (22.5, 21.3 and 28.4%, respectively). Among horses and donkeys, the prevalence of these lesions was influenced by the type of work carried out. Lesions on the head, neck, ribs, flank and tail base were seen in less than 10% of animals. Across all three species approximately 70% of animals were thin, having a body condition score (BCS) of 2 or less on a scale of 1-5 (1, very thin; 5, very fat) and more horses were in very thin condition (BCS 1) than mules or donkeys. Over 75% of animals demonstrated limb deformities and abnormalities of gait. The results of this study are being used as the initial stage of a long-term strategy to inform priorities for welfare interventions in working equines and to establish a welfare benchmark. Subsequent stages will rank the welfare concerns identified, assess the contributing risk factors and implement specific interventions to address these risks. Following intervention, success in improving welfare will be measured by repetition of this protocol and comparison with the benchmark.

Systematic clinical examinations for identification of latent udder health types in Danish dairy herds

A cross-sectional study was conducted to explore the applicability of systematic clinical examinations of udders as an additional tool for the evaluation of udder health status on dairy farms. During 2000, each of the 16 dairy farms was visited 5 times; 20 cows per farm were chosen at random at each visit for clinical udder examination immediately after milking. The clinical examination included both pathological and morphological variables. One examination per cow was included in the analysis (n = 707 cows). Principal component analysis (PCA) was performed in 3 steps. First, 19 variables characterizing udder and teats were analyzed (PCA 1). Second, the variables parity and stage of lactation were included (PCA 2). Finally, somatic cell count (SCC) and milk yield (PCA 3) were included. The PCA resulted in 4 components that explained 30% of the variation of the data: 1) small udder, 2) distressed udder, 3) mastitis udder, and 4) soiled udder. Variables with high positive correlation to the "small udder" were small udder shape, short teats, and first parity. Impaired teat surface, hard udder texture, and a long udder shape were related to the "distressed udder." The "mastitis udder" was characterized by the clinical variables asymmetry between front quarters, asymmetry between hind quarters, knotty tissue, and acute clinical mastitis. Reduced milk yield and high SCC were related to the "mastitis udder," whereas low SCC was related to the "small udder." The "soiled udder" was related to early lactation. Including this information in the assessment of udder health may be of substantial value for data analysis in farms with suspected under-reporting of clinical mastitis.

Disposal and disease rates in British dairy herds between April 1998 and March 2002

Data derived over four years from 434 dairy herds in 1998/99 to 244 in 2001/02 revealed average disposal rates of 22.6 per cent per year, half of which were for poor fertility, mastitis and lameness. The quartile of herds with the lowest disposal rates sold an average of 11.5 per cent annually and the quartile with the highest rates sold 35.5 per cent. Average annual disease rates over the four years were as follows: for assisted calving 7.8 per cent, for digestive disease 1.2 per cent, for ketosis 0.5 per cent, for hypomagnesaemia 0.5 per cent, for hypocalcaemia 5.0 per cent and for injuries 0.8 per cent. The incidence of mastitis increased from 36.0 to 43.3 per cent of cows per year. The incidence of lameness decreased from 23.3 per cent in 1998/99 to 20.7 per cent in 2000/01 but increased to 21.9 per cent in 2001/02. Data received from the same 219 farms during the first three years showed no effective differences from the full set of data for each of the three years. The lowest annual incidences of mastitis and lameness on individual farms were below 7 per cent and 2.5 per cent, respectively. In general, housing cows in cubicles was associated with a greater risk of lameness, and housing them in straw yards with a greater risk of mastitis. However, some of the lowest rates of lameness were recorded in cubicle-housed cows and some of the lowest rates of mastitis were recorded in cows housed in yards. Larger herds were not associated, in general, with higher rates of mastitis.

Welfare assessment: indices from clinical observation

It is not enough to study animal welfare; our responsibility is to promote it. To this end, we need to step out of our laboratories and develop robust protocols for assessing welfare in groups of animals on farms or in the laboratory. While these protocols must incorporate principles derived from detailed scientific study they will, in practice, need to be based on clinical observations and records that an assessor can acquire at a single visit. Such assessments must also be comprehensive: approaches based only on behaviour, or motivational state, or physical appearance, or performance records, can never tell the full story. The ‘Five Freedoms’ provide a comprehensive template that incorporates the different elements that define welfare state. However they only describe welfare at the time of observation. Protocols, for example, for on-farm assessment need to include measurements and records that provide evidence of long-term consequences of the quality of husbandry practices (eg body condition, chronic injuries). This paper reviews approaches developed at Bristol for the on-farm evaluation of welfare in dairy cows and free-range hens. The criteria used to assess welfare from clinical evidence were developed through expert consultation using the ‘Delphi’ review process. Experts were also asked to make value judgements as to the seriousness of different elements of poor welfare by indicating the point at which intervention would be necessary to resolve specific problems. This study identified a serious limitation of Quality Assurance schemes that seek to encompass many different elements of welfare into a single index that ranks overall welfare as acceptable or unacceptable. Specific farms had specific welfare problems and these required specific solutions.

An Animal-Based Welfare Assessment of Group-Housed Calves on UK Dairy Farms

A series of measures of calf welfare was developed through a process of expert consultation. A welfare assessment of group-housed calves was carried out on 53 UK dairy farms during the winter of 2000/01. The assessment used animal-based measures including direct observation of the calves and examination of their health history through a review of farm records. The findings from this were compiled into a profile of calf welfare which outlined the range of results for each measure used. The results fell into the three categories of respiratory health, nutrition and general appearance. A broad range of results was found across the farms visited for the measures in each of these categories. Some farms performed well for all measures taken, and no farms performed consistently badly across all aspects of calf welfare. The majority of farms combined aspects of both good and poor welfare performance.

Preliminary Investigation Into the Use of Expert Opinion to Compare the Overall Welfare of Dairy Cattle Farms in Different Farm Assurance Schemes

This paper describes an approach to assessing the overall welfare of cows on dairy farms. Veterinary and behaviour experts were shown results for ten selected welfare parameters for 25 pairs of dairy farms paired for farm assurance status but with similar geographical location and husbandry system. From this information alone they were asked to state which farms had better welfare. Overall, there were no significant differences between the conclusions of veterinary and behaviour experts. There was a significant relationship between the proportion of experts rating a farm as poorer and the measured difference in the number of cows with lameness or rising restrictions between the paired farms. There were no significant relationships between the expert decisions and differences in milk yield, flight distance, swollen hocks, mastitis incidence, dystocia level, conception rates, prevalence of thin cows and proportion of cows with dirty udders. Clearly, experts rate lameness and discomfort as highly important indices of poor welfare in dairy cows.

Effect of the RSPCA Freedom Food Scheme on the welfare of dairy cattle

To evaluate the effect of the Royal Society for the Prevention of Cruelty to Animals Freedom Food (FF) scheme on the welfare of dairy cattle in England, 28 FF and 25 non-FF farms were assessed during the winter of 2000 to 2001. The assessments were based on a protocol which included the examination of the farms' records, the farmers' estimates of the incidence of disease, and independent observations of the behaviour and physical condition of the cows. The data were analysed to identify which measures of welfare were affected by FF membership and to assess the number of farms on which intervention would be required, as defined by a panel of 50 experts. The FF farms had better results for 12 of the welfare indicators, including those for mastitis, non-hock injuries, cow cleanliness and body condition, and poorer welfare indicators for eight of the measures, including hock injuries, lameness and restrictions in rising behaviour. Except for the prevalence of dull coats (which was lower on the FF farms) there were no significant differences in the proportions of FF and non-FF farms on which intervention was required according to the experts' assessment.