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1 A new group IIa sPLA 2 inhibitor was compared with selective inhibitors of COX-1, COX-2 and an LTC 4 antagonist for effects on local and remote tissue injuries following ischaemia and reperfusion (I/R) of the small intestine in rats.2 In an acute model of ischaemia (30 min) and reperfusion (150 min) injury in the absence of inhibitors, there was significant intestinal haemorrhage, oedema and mucosal damage, neutropenia, elevated serum levels of aspartate aminotransferase (AST) and hypotension. 3 Preischaemic treatment with the inhibitor of sPLA 2 (Group IIa), at 5 mg kg À1 i.v. or 10 mg kg À1 p.o. significantly inhibited I/R-induced neutropenia, the elevation of serum levels of AST, intestinal oedema and hypotension.4 Pretreatment with the COX-2 inhibitor celebrex (10 mg kg À1 i.v.) and the LTC 4 antagonist zafirlukast (1 mg kg À1 i.v.) also showed marked improvement with I/R-induced AST, oedema and neutropenia. Hypotension was only reduced by the LTC 4 antagonist. The COX-1 inhibitor flunixin (1 mg kg À1 i.v.) did not effect improvement in the markers of tissue injury. 5 Histological examination of rat I/R injury showed that all of the drugs offered some protection to the mucosal layer damage compared to no drug treatment. Given i.v., the sPLA 2 inhibitor was more effective than either the COX-1 or COX-2 inhibitors in preventing rat I/R injury. 6 These results indicate that a potent new inhibitor of sPLA 2 (group IIa) protects the rat small intestine from I/R injury after oral or intravenous administration. COX-2 and LTC 4 inhibitors also showed some beneficial effects against intestinal I/R injury. Our study suggests that sPLA 2 (Group IIa) may have a pathogenic role in intestinal I/R in rats.

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This study consisted of a survey of dairy farmers and their milking sheds at 198 Victorian dairy farms to examine the relationships between physical features in the milking shed and a number of job-related characteristics of the farmer, such as attitudes to handling cows and job satisfaction. Furthermore, farmers’ opinions of the effects of specific design features of the milking shed on cow behaviour were sought. A further objective of this survey was to use the relationships between shed characteristics and job-related characteristics of the farmer to identify, for future research, possible features of the milking shed that may affect cow behaviour. There was substantial variation in both the behavioural beliefs of farmers about cow behaviour in the milking shed and reports by farmers on comfort and working conditions in the dairy, indicating that considerable opportunities exist to improve these key job-related characteristics. A principal component analysis (PCA) of the responses to the questions on job-related characteristics of the farmer identified 6 factors: 2 of the factors identified were related to behavioural beliefs by farmers about cow behaviour (labelled ‘Cow Movement’ and ‘Cow Behaviour’); one of the factors related to comfort of the farmer in the shed (labelled ‘Operator Comfort’); and 3 of the factors related to aspects of the quality of life of the farmer (labelled ‘Workload’, ‘Farmer Mood’, and ‘Job Characteristics’). Positive beliefs about both cow movement (factor called Cow Movement) and cow behaviour (factor called Cow Behaviour) were correlated with farmers being more positive about working in the dairy (factor called Operator Comfort; P < 0.05 and P < 0.01, respectively) and the characteristics of the job (factor called Job Characteristics; P < 0.01). These relationships suggest that improvements in cow behaviour may lead to improvements in both job satisfaction and the quality of life of the farmer. Furthermore, regression analysis revealed that a number of the shed features, such as height of the breast rail, presence of stall gates, length and width of the platform and solid side on first milking bail, were significant predictors of one or more of these 6 PCA factors. Although these results may not reflect causal relationships, these relationships between shed characteristics and a number of job-related characteristics of the farmer highlight the potential importance of shed design to both the cow and the farmer and provide a valuable guide in identifying features of milking sheds that require future examination as to their effects on cow behaviour.

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The ability of cows (Bos taurus) to perceive depth has never been experimentally investigated. If cows can perceive depth, the milking pit in commercial milking facilities may be fear provoking for dairy cows, as past research has shown that most land-dwelling species possess an instinctive fear of heights. In the current study, 12 dairy heifers (1-year-old cows) were exposed to a milking pit (depth-exposed group) and 13 heifers (control group) were exposed to a standard change in the environment while they moved through a milking facility over a 5-day treatment period. Heifers in the depth-exposed group showed a higher heart rate (p < .05) and stopped more often (p < .05) than did those in the control group; persistence of heart rate but not of behavioral responses on repeated exposures indicated that some habituation to the depth stimulus had occurred. Depth exposure had no effect on cortisol concentrations or on ease of handling. These results indicate that heifers responded differently to a change in depth than they did to a standard change in the environment and provide evidence of both depth perception and acute fear of heights in cows.

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