Journal Articles

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    Can we estimate herd-level prevalence of lameness in dairy cow herds kept at pasture by sampling part of the herd?
    (Taylor and Francis Group on behalf of the New Zealand Veterinary Association, 2025-03-26) Sapkota S; Laven RA; Müller KR; Yang DA
    Aims: To assess whether herd-level lameness prevalence can be estimated on New Zealand dairy farms, by scoring the first, middle, or last 100 cows in the milking order. In pasture-based herds, whole herd locomotion scoring requires an assessor outside the milking parlour throughout milking. If sufficiently predictive, sampling a proportion of the herd based on milking order, could reduce the costs and time of welfare assessments. Methods: Six pasture-based, spring-calving, dairy farms in the Manawatū region of New Zealand were conveniently selected. Visits occurred at approximately 6-week intervals between October 2021 and May 2022. Cows were scored using the DairyNZ lameness score (0–3). The assessor tallied cows as they left the parlour and recorded the milking order of those with a lameness score ≥ 2. Data were analysed to determine the association between farm, visit and the proportion of lame cows in the first, middle, and last 100 cows, and the agreement between the prevalence of lame cows in those groups and from whole herd scoring. Results: Across all visits, 263 lame cows were recorded. Of these, 40.7% were in the last 100, 25.9% in the middle 100, and 14.4% in the first 100. Farm, visit and their interactions with group were all statistically significant (p < 0.001). While, overall, the last 100 cows had the highest proportion of lame cows, this pattern varied across farms and visits, Limits-of-agreement plots showed that as herd prevalence increased, agreement between the prevalence in each sample group and herd prevalence worsened. When herd prevalence exceeded 5%, only the middle 100 sampling group had a limits-of-agreement < 5%. Conclusions: Variations across farms and seasons in the proportion of lame cows in each part of the milking order lead to variations in the accuracy of predicting overall lameness from such samples. Based on limits-of-agreement, observing the middle 100 cows is likely to be the most accurate sample, but is still likely to be of limited value on New Zealand dairy farms, especially as a single, one-off measurement. Clinical relevance: On New Zealand dairy farms, locomotion scoring the middle 100 cows in the milking order as part of a welfare assessment would reduce costs and time but would not produce an accurate estimate of whole-herd lameness prevalence. However, it may be useful as a screening tool in herds routinely locomotion scoring throughout the year.
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    Repeatability of whole herd lameness scoring: an analysis of a New Zealand dataset
    (Taylor and Francis Group, 2024-09-03) Laven RA; Mason WA; Laven LJ; Müller KR
    AIMS: To assess whether a whole-herd lameness score on a New Zealand dairy farm in spring could predict lameness prevalence on the same farm in summer (and vice versa) and whether a single-herd lameness score could be used to determine whether herd lameness prevalence was < 5% in both spring and summer. METHODS: Prevalence data (proportion of the herd with lameness score ≥ 2 and with score 3; 0-3 scale) from a study where 120 dairy farms across New Zealand were scored in spring and in the following summer were analysed using limits-of-agreement analysis. In addition, farms were categorised as having either acceptable welfare (lameness prevalence < 5% in both spring and summer) or not (lameness prevalence ≥ 5% in either spring or summer or both). The accuracy and specificity of a single, whole-herd lameness score at identifying herds with acceptable welfare were then calculated. RESULTS: The limits-of-agreement analysis suggests that 95% of the time, the prevalence of lameness in summer would be expected to be between 0.23 and 4.3 times that of the prevalence in spring. The specificity and accuracy of identifying a farm as acceptable on both occasions from a single observation were, respectively, 74% and 92% in spring, and 59% and 87% in summer. CONCLUSIONS: A single, one-off, whole-herd lameness score does not accurately predict future lameness prevalence. Similarly, acceptable status (lameness prevalence < 5%) in one season is not sufficiently specific to be used to predict welfare status in subsequent seasons. CLINICAL RELEVANCE: Whole-herd lameness scoring should be used principally as a means of detecting lame cows for treatment. A single whole-herd lameness score by an independent assessor should not be used to determine a herd's welfare status.
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    Assessing animal welfare during a stranding of pygmy killer whales (Feresa attenuata)
    (John Wiley and Sons, Inc., 2023-10-01) Boys RM; Beausoleil NJ; Hunter S; Betty EL; Hinton B; Stockin KA
    Empirical assessment of cetacean welfare to inform stranding interventions is lacking. Here, potential welfare indicators are described for two stranded pygmy killer whales (Feresa attenuata), along with euthanasia procedures and pathology of potential relevance. The animals were filmed for 3.5 and 1.5 hr, respectively, allowing assessment of 19 indicators, including animal behaviors and human interventions. Eight interventions and 19 animal behaviors were identified; 17 and 11 behaviors were displayed by animal 1 and 2, respectively. Examination of ballistics euthanasia revealed atypical projectile placement and characterized animal behavioral responses, but welfare implications could not be assessed as insensibility was not verified in-field. Pulmonary edema and renal degeneration were documented in both animals; differential etiologies include ischemia–reperfusion, shock, and/or myopathy. Potential relationships among histopathology and welfare indicators are explored to infer affective experiences. For example, simultaneous head-lifting with respiration increased over time which, alongside pulmonary edema, suggests these animals experienced breathlessness. Other likely affective states include fatigue and discomfort; there are insufficient data to estimate the intensity or duration of these experiences or to provide an overall welfare grade/score. Further data are required to validate the proposed welfare indicators and to progress development of holistic approaches to welfare assessment at cetacean strandings.
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    Mental Experiences in Wild Animals: Scientifically Validating Measurable Welfare Indicators in Free-Roaming Horses
    (MDPI (Basel, Switzerland), 2023-04-28) Harvey AM; Beausoleil NJ; Ramp D; Mellor DJ; Padalino B
    The mental experiences of animals are what characterises their welfare status. The Five Domains Model for assessing welfare aligns with the understanding that physical and mental states are linked. Following measurement of indicators within each of the four physical/functional Domains (1. Nutrition; 2. Physical environment; 3. Health; and 4. Behavioural interactions), the anticipated negative or positive affective consequences (mental experiences) are cautiously inferred and assigned to Domain 5. Those inferences derive credibility from validated knowledge of the underlying systems of physiology, neurophysiology, neuroethology and affective neuroscience. Any indicators used for assessing welfare need to be scientifically validated. This requires, firstly, evidence of the links between a measurable/observable indicator and the physical/functional impact (in Domains 1 to 4), and secondly, a demonstrable relationship between the physical/functional impact and the mental experience it is inferred the indicators reflect (in Domain five). This review refers to indicators of physical/functional states in Domains 1 to 4, which have been shown to be measurable in free-roaming wild horses, and then evaluates the scientific evidence linking them to inferred mental experiences in Domain 5. This is the first time that the scientific evidence validating a comprehensive range of welfare indicators has been synthesised in this way. Inserting these indicators into the Five Domains Model enables transparently justifiable assessment and grading of welfare status in free-roaming horses.
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    Animal Welfare Assessment: Can We Develop a Practical, Time-Limited Assessment Protocol for Pasture-Based Dairy Cows in New Zealand?
    (MDPI (Basel, Switzerland), 19/10/2020) Sapkota S; Laven R; Müller K; Kells N
    Despite being a leading producer and exporter of dairy products, New Zealand has no industry-recognised welfare assessment protocol. A New Zealand-specific protocol is essential, as almost all dairy farms in New Zealand are pasture-based and housing is rarely used. Therefore, protocols developed for intensive cows are not suitable. The aim of this study was to develop a simple yet practical welfare assessment protocol that could be used to assess the welfare of a dairy herd during one visit timed to occur around milking. Six welfare assessment protocols and four studies of dairy cattle welfare assessments that had some focus on dairy cattle welfare at pasture were used, along with the New Zealand Dairy Cattle Code of Welfare, to identify potential assessments for inclusion in the protocol. Eighty-four potential assessments (20 record-based and 64 that needed assessing on-farm) were identified by this process of welfare assessments. After screening to exclude on-farm assessments that were not relevant, that had only limited practical application in pasture-based dairy cows or that required more time than available, 28 on-farm assessments remained, which were put together with the 20 record-based assessments and were tested for feasibility, practicality and time on two pasture-based dairy farms. Assessments were then identified as suitable, suitable after modification or not feasible. Suitable and modified assessments were then included in the final protocol alongside additional measures specific to New Zealand dairy farms. The final protocol included 24 on-farm assessments and eight record-based assessments. Further testing of these 32 assessments is needed on more dairy farms across New Zealand before the protocol can be used to routinely assess the welfare of dairy cows in New Zealand.