Short communication: The effect of temperature-humidity index on milk yield and milking frequency of dairy cows in pasture-based automatic milking systems.

Hot weather is known to negatively affect cow performance primarily through reduced feed intake and milk yield. However, little information is available on how it affects cow milk yield and milking frequency in automatic milking systems (AMS). Milking data were collected from 6 pasture-based AMS farms in Australia to assess the effect of temperature-humidity index (THI) on milk yield and milking frequency. Daily measures of average milk yield per cow and average milking frequency per cow during December to February (Australian summer) were assessed for associations with maximum, minimum, and average THI from d 0, -1, -2, and -3 in relation to the milking data. Average daily milk yield per cow was negatively associated with an increasing maximum, minimum, and average THI (-0.11, -0.08, and -0.15 kg/THI unit increase, respectively) on the collection day and up to 3 d prior. The average daily milking frequency was negatively associated with maximum THI on 1 d (-0.003/THI unit increase) and 2 d (-0.003/THI unit increase) before collection. Our results show that high THI conditions were negatively associated with milking frequency and milk yield in a pasture-based AMS and that research into management and infrastructure (cow cooling) in these systems is warranted to reduce production losses.

The effects of direct and indirect road transport consignment in combination with feed withdrawal in young dairy calves.

Male dairy calves may be transported from their farm of origin at a young age. This process may involve an extended period off feed and indirect consignment through an intermediate facility, prompting potential welfare concerns. To assess the impact of transport, 59 male Holstein-Friesian dairy calves (5-9 d old) were either (1) held in situ on farm (control); (2) transported for 6 h; (3) transported for 12 h; or (4) transported for 1 h to a holding facility where they were kept for 6 h and then transported for 5 h. All treatments included a 30-h period of feed (milk) withdrawal, and calf responses were measured over time from before their last feed until the completion of the study after the transport and feed withdrawal periods. Apart from increases in serum creatine kinase in calves transported for 12 h, transported calves generally did not differ in blood concentrations of glucose, beta-hydroxybutyrate, lactate, total protein or in packed cell volume, compared with controls (P>0.05). Calf responses to the indirect consignment treatment did not differ from those of other transported calves. Withdrawal of feed for 30 h caused calves to lose 6% of body weight; blood glucose varied from 3.96 mmol/l immediately before daily feeding to 5.46 mmol/l at 3 h post feeding, and then declined to 3.43 mmol/l at 30 h. Calves lay down for 22-32% of the time during transport, and did not show a rebound effect in lying behaviour post arrival in comparison with controls. Best practice transport of 6-12 h duration, including indirect consignment via a holding facility, did not significantly affect calf blood biochemistry and metabolism in comparison with untransported animals. However, extending the time off feed beyond the daily feeding interval resulted in reduced blood glucose concentrations, suggesting that time off feed needs to be carefully managed in young transported dairy calves.

Temperament Behaviours in Individually Tested Sheep Are Not Related to Behaviours Expressed in the Presence of Conspecifics.

Individual behavioural testing in sheep is common; however, outcomes may be misleading as they are a highly gregarious species that is usually managed in groups. We investigated whether behaviour expressed by 3-4-month-old Merino lambs (n = 220) in social isolation was related to their behaviour towards the same stimuli when three other conspecifics were present, and if measures of temperament (vocalisations and locomotory behaviours) were repeatable across both social situations. Expression of all behaviours were reduced when conspecifics were present, and vocalisations were rarely performed in social groups, suggesting that this behaviour is a response to social isolation. Similarities across the two social situations, in ranked order of how individual lambs expressed each behaviour, indicate that vigilance and attentional orienting towards a human were repeatable (p < 0.001), as was vigilance in a startle test (p < 0.05). However, no clear relationship between behaviours expressed across the two social situations was found. The results of this study suggest that testing sheep individually should be conducted with caution where the outcome is applied to animals managed in groups. Vigilance shows promise as a measure of an underlying trait that is stable across social contexts.

Behavioural reactivity testing in sheep indicates the presence of multiple temperament traits.

Temperament in sheep is commonly presented as unidimensional, with a 'nervous' temperament indicative of fear and reactivity towards humans and novel environments. However, temperament is multidimensional, with some traits expressed only under certain conditions (context-specific). There is evidence that a common temperament test in sheep, the isolation-box (IB), measures level of activity and not fearfulness as intended, and that behaviours measured in the IB test are indicative of different traits. To investigate this, 16 behavioural responses to a human, to being startled, and to confinement (IB test) were measured in 89 lambs, twice, three months apart. Our results agree with previous studies that vocalisations in all tests and locomotion in two, show high repeatability over time. A principal component analysis identified that vocalisations are domain-general, and are indicative of the trait 'sociability', however locomotion is context-specific' and captures the traits 'exploration-avoidance', 'boldness-shyness' and 'general activity'. A cluster analysis identified four behavioural profiles that indicate the trait 'boldness-shyness' captures reactivity towards humans. This suggests the IB test, which measures 'general activity', is unsuitable for measuring reactivity towards humans in sheep, and that when studying the impact of temperament on other factors, multiple conditions should be used when identify temperament traits.

Exposure to humans after weaning does not reduce the behavioural reactivity of extensively reared Merino lambs.

Human-directed fear in extensively reared sheep is often high due to the aversive nature of common husbandry procedures and infrequent interactions with humans. This study investigated whether additional human exposure provided to weaned lambs reduced human-directed fear and behavioural reactivity. Ninety Merino lambs were either exposed to low or moderately stressful human exposure sessions, or had no additional human contact, and their fear responses and behavioural reactivity to humans, a startle stimulus and confinement were tested. Overall, the imposed interventions did not reduce behavioural reactivity during these tests, suggesting fear towards humans had not been altered.

The Human-Horse Relationship: Identifying the Antecedents of Horse Owner Attitudes towards Horse Husbandry and Management Behaviour.

The welfare of recreational horses is an important issue. Horse owner attitudes towards horse ownership are likely to influence owner behaviour in terms of horse husbandry and management practices and human-horse interactions, which in turn are likely to affect the welfare of the horse. Based on Ajzen's Theory of Planned Behaviour, this paper examines the relationships between horse owner attributes, specifically background factors (demographics, knowledge, and experience) and attitudes (beliefs) towards horse husbandry and management behaviour. Data were collected via a random telephone survey and during on-site inspections with Victorian horse owners and their horses (n = 57), using an attitude questionnaire. Relationships were found between horse owner background factors and horse owner attitudes towards horse husbandry and management behaviour. Generally, belief variables correlated significantly with background factors that were primarily related to knowledge and experience. Further, beliefs concerning three key husbandry practices (parasite control, hoof care, and dental care) all appear to be predicted to some degree by background factors associated with knowledge and experience. Therefore, a practical recommendation may be the implementation of education and training programs aimed at improving horse owner knowledge and experience regarding effective horse husbandry and management to promote horse welfare. Clearly, further research is warranted.

Biochemistry and hematology reference intervals for neonatal dairy calves aged 5-12 days.

BACKGROUND: Comprehensive hematology and biochemistry RIs are currently lacking in the literature for young dairy calves based on sample sizes more than 120. Young dairy calves are at a relatively high risk of poor health and welfare outcomes. They have a high risk of morbidity and mortality in the first 2 weeks of life, and many are transported and fasted during this time. For example, non-replacement calves in Australia and New Zealand are usually 5-12 days old when transported to abattoirs, meaning that calves of this age group are potentially at risk of both health and welfare compromise. Given these factors, sound, comprehensive, age-specific biochemical and hematologic RIs are needed for both veterinary clinical practice and to inform research on calf health and welfare. OBJECTIVES: The aim of this study was to generate age-specific hematology and biochemistry RIs for dairy calves aged 5-12 days. METHODS: We collected blood samples from 141 fasted, healthy dairy calves on 10 Australian farms. Reference Value Advisor software was used to calculate nonparametric RIs for multiple biochemistry and hematology variables. RESULTS: RIs for a panel of hematology and biochemistry variables in dairy calves aged 5-12 days old were derived. CONCLUSIONS: These RIs will be useful for clinical veterinary practice, as well as for research on dairy calf health and welfare.

Remotely Sensed Imagery for Early Detection of Respiratory Disease in Pigs: A Pilot Study.

Respiratory diseases are a major problem in the pig industry worldwide. Due to the impact of these diseases, the early identification of infected herds is essential. Computer vision technology, using RGB (red, green and blue) and thermal infrared imagery, can assist the early detection of changes in animal physiology related to these and other diseases. This pilot study aimed to identify whether these techniques are a useful tool to detect early changes of eye and ear-base temperature, heart rate and respiration rate in pigs that were challenged with Actinobacillus pleuropneumoniae. Clinical observations and imagery were analysed, comparing data obtained from animals that showed some signs of illness with data from animals that showed no signs of ill health. Highly significant differences (p < 0.05) were observed between sick and healthy pigs in heart rate, eye and ear temperature, with higher heart rate and higher temperatures in sick pigs. The largest change in temperature and heart rate remotely measured was observed around 4-6 h before signs of clinical illness were observed by the skilled technicians. These data suggest that computer vision techniques could be a useful tool to detect indicators of disease before the symptoms can be observed by stock people, assisting the early detection and control of respiratory diseases in pigs, promoting further research to study the capability and possible uses of this technology for on farm monitoring and management.

Computer vision and remote sensing to assess physiological responses of cattle to pre-slaughter stress, and its impact on beef quality: A review.

Pre-slaughter stress is well-known to affect meat quality of beef carcasses and methods have been developed to assess this stress. However, development of more practical and less invasive methods are required in order to assess the response of cattle to pre-slaughter stressors, which will potentially also assist with the prediction of beef quality. This review outlines the importance of pre-slaughter stress as well as existing and emerging technologies for quantification of the pre-slaughter stress. The review includes; i) indicators of meat quality and how they are affected by pre-slaughter stress in cattle, ii) contact techniques that have been commonly used to measure stress indicators in animals, iii) remotely sensed imagery techniques recently used as non-invasive methods to monitor physiological and behavioural parameters and iv) potential implementation of remotely sensed imagery data to perform contactless assessment of physiological measurements, which could be related to the pre-slaughter stress, as well as to the indicators of beef quality. Relevance to industry, conclusions and recommendations for research are included.

Modelling and Validation of Computer Vision Techniques to Assess Heart Rate, Eye Temperature, Ear-Base Temperature and Respiration Rate in Cattle.

Precision livestock farming has emerged with the aim of providing detailed information to detect and reduce problems related to animal management. This study aimed to develop and validate computer vision techniques to track required features of cattle face and to remotely assess eye temperature, ear-base temperature, respiration rate, and heart rate in cattle. Ten dairy cows were recorded during six handling procedures across two consecutive days using thermal infrared cameras and RGB (red, green, blue) video cameras. Simultaneously, core body temperature, respiration rate and heart rate were measured using more conventional 'invasive' methods to be compared with the data obtained with the proposed algorithms. The feature tracking algorithm, developed to improve image processing, showed an accuracy between 92% and 95% when tracking different areas of the face of cows. The results of this study also show correlation coefficients up to 0.99 between temperature measures obtained invasively and those obtained remotely, with the highest values achieved when the analysis was performed within individual cows. In the case of respiration rate, a positive correlation (r = 0.87) was found between visual observations and the analysis of non-radiometric infrared videos. Low to high correlation coefficients were found between the heart rates (0.09-0.99) obtained from attached monitors and from the proposed method. Furthermore, camera location and the area analysed appear to have a relevant impact on the performance of the proposed techniques. This study shows positive outcomes from the proposed computer vision techniques when measuring physiological parameters. Further research is needed to automate and improve these techniques to measure physiological changes in farm animals considering their individual characteristics.

The Effect of Age, Stocking Density and Flooring during Transport on Welfare of Young Dairy Calves in Australia.

Transport of young ('bobby') calves for slaughter is a contentious welfare issue for some sectors of the Australian community. Factors of age, stocking density and flooring need further research to develop appropriate welfare standards for transport of bobby calves. The objective of this study was to identify the space allowance requirements for transport of bobby calves and to understand factors such as age and flooring that minimise risks to calf welfare during transport. Animals aged 3-, 5- and 10-day old were transported for 12 h in a custom-made cattle truck fitted with 9 pens, with movable mesh divisions. Each pen contained 4 calves, with space allowances of 0.2, 0.3 and 0.5 m² per calf and flooring of solid metal, mesh or straw bedding. A total of 432 male dairy calves were transported in 12 trips during the 2-year study. Behavioural measurements included lying during transport, and lying and drinking for 12 h after transport during recovery. Blood samples were taken prior to transport, immediately after transport and 12 h after transport. Blood samples were analysed for metabolic state (glucose, beta-hydroxy-butyrate (BOHB)), hydration (packed cell volume (PCV)) and exhaustion/bruising (creatine kinase (CK) activity). It was found that several measures were affected by age, which indicates that the physiology and in particular lying behaviour of 3-day old calves is fundamentally different from that of older calves. It is unclear how this affects their ability to cope with the stressors of transport. Space affected the posture changes and CK activity during and after transport and it is concluded that space allowance should be at least 0.3 m² per calf for calves of average size, while CK activity suggested that providing more space to 0.5 m² per calf may provide even greater benefits. Straw bedding is of clear benefit to calves during transport, to the extent that it may even reduce some of the negative effects of reduced space on lying behaviour.