J. L. Barnett

Behavioural response to humans and the productivity of commercial dairy cows

This study examined the relationships between the attitude and the behaviour of the stockperson towards cows and the behavioural response to humans and the milk production of cows at 31 commercial dairy farms over one lactation. The attitude of the stockperson was measured on the basis of the stockpersons opinion of the cows behaviour and how the stockperson evaluated his own behaviour. The behaviour of the stockperson was measured by recording the nature and frequency of the tactile interactions and some visual and auditory interactions directed towards the cows. The behavioural response of cows to humans was assessed by observing their approach behaviour to an unfamiliar experimenter in a standard test and production records were collected for the entire lactation at each farm. Correlation and regression analyses using farm averages were used to examine relationships between human and cow variables. Several cow behaviour variables, indicative of fear of humans, were moderately (P<0.05) to highly (P<0.01) correlated with milk yield and composition and regression analysis indicated that fear of humans accounted for 19% of the variation in milk yield between farms. The results suggest that at farms where milk yield was low, cows showed less approach to the experimenter in the standard fear test than at farms where milk yield was higher. A composite attitude score, based on the responses of stockpeople to questions about patting and talking to cows, ease of movement of cows and cows recognising unfamiliar stockpeople, was moderately (P<0.05) to highly (P<0.01) correlated with the behaviour of the stockperson. While a number of stockperson behaviour variables were correlated (P<0.05) with milk yield, the former variables were generally poorly correlated with cow behaviour. Therefore these preliminary findings provide evidence that, as seen in the pig industry, sequential relationships may exist between the attitude and behaviour of the stockperson and the behaviour and productivity of commercial dairy cows. Research is required to further examine these relationships because of the possible implications on cow productivity and welfare.

A survey of dog ownership in suburban Australia—conditions and behaviour problems

There has been an increasing emphasis in Australia on confining dogs to owner’s properties (household backyards) as a solution to problems of dog aggression. Therefore, there is a need to determine the social and physical conditions that make up the dog’s backyard environment and how these factors may affect dog behaviour and welfare. The aim of this study was to provide an overview of the conditions provided to dogs in suburban Melbourne (Australia) and any behavioural problems associated with these conditions. A survey of 203 dog owners across suburban Melbourne was conducted. The questionnaire consisted of questions relating to demographics, the dogs’ routine and confinement and what behaviours the owners observed in their dogs. The relationship between some of the environmental factors and the occurrence of problem behaviour was then examined. The main behaviour problems reported by owners were overexcitement (63%) and jumping up on people (56%). Some of the factors that were correlated with the occurrence of problem behaviours included how well the dog obeyed commands (P<0.01), whether the owner had owned a dog before (P<0.01) and how much time was spent with the dog (P<0.01). Dogs that had obedience training were more likely to obey commands than those that that did not (P<0.01) and large dogs were more likely to receive training than small dogs (P<0.01). These findings provide an interesting insight into some of the factors that may be related to the occurrence of behaviour problems in dogs.

Improving the attitude and behaviour of stockpersons towards pigs and the consequences on the behaviour and reproductive performance of commercial pigs

This study examined firstly whether it is possible to improve the attitudinal and behavioural profiles of stockpersons towards pigs and, if successful, secondly the consequences of these attitudinal and behavioural changes on the behaviour and productivity of commercial breeding pigs. Two treatments were imposed: a modification treatment, consisting of a cognitive-behavioural intervention procedure designed to modify the behaviour of stockpersons towards pigs; a control treatment, where no intervention was attempted. Thirty-five commercial farms were selected for study on the basis of their suitability and 25 farms completed this 2 year study (13 modification and 12 control). The effectiveness of the intervention programme was assessed by monitoring the changes in the attitudinal and behavioural profiles of stockpersons, and the behaviour and reproductive performance of pigs at the two groups of farms from an 8 month pre-modification period to a 15 month post-modification period. An analysis of the proportional changes in the attitude, behaviour and production variables from the pre-modification period to the post-modification period revealed some significant treatment effects on both the attitude and behaviour of the stockpersons towards pigs, and the behavioural response of pigs to humans. For example, the modification treatment resulted in a greater (P<0.05) increase in the total score given by the stockperson to those attitude questions relating to petting and talking to pigs, indicative of a more positive belief towards these behaviours. Corresponding with this relative improvement in the attitude of stockpersons at the modification farms was a significant (P<0.01) reduction in the percentage of physical interactions displayed by the stockperson which were negative in nature at the modification farms relative to stockpersons at the control farms. These relative improvements in the attitude and behaviour of stockpersons at the modification farms corresponded with a significant relative reduction in the level of fear of humans by pigs at these farms. There were increases (P<0.05) in the time that pigs spent within 0.5 m of the experimenter and in the number of interactions with the experimenter in the standard test for pigs at the modification farms relative to pigs at the control farms. While the difference was not significant (P<0.11), there was a strong tendency for an increase in the number of pigs born per sow per year at the modification farms relative to the control farms (+6% and −3%, respectively). In general, these results, together with the results on the adverse effects of increasing the level of fear in experimental pigs, indicate that fear of humans may be an integral component in the pathway(s) in which human factors, such as human attitude and behaviour, affect animal productivity and welfare.

Sources of sampling variation in saliva cortisol in dogs.

The main advantage of collecting saliva cortisol as opposed to plasma cortisol is that it is non-invasive and therefore it is now widely used in stress measurement studies on farm animals and dogs. Although a plasma cortisol response to handling associated with blood collection generally occurs at 3 min from the commencement of handling, there is no information in the literature on the time course of the response of salivary cortisol concentration to handling. The aims of these experiments were to (1). determine if there is a response to up to 4 min handling that affects cortisol concentration in saliva and (2). determine the main causes of variation in saliva cortisol in dogs over time. In experiment 1, saliva was collected from six Kelpies at 0 min then 2, 3 or 4 min after the commencement of restraint. There was no handling effect found in up to 4 min sampling time. In experiment 2, saliva was collected from six Labrador Retrievers five times in 2 h (14:00-16:00), three days a week for four weeks. Some of the sources of variation in saliva cortisol over time included between dog variation that varied over a period of days and variation between occasions that affected the group of dogs as a whole.

The welfare of extensively managed dairy cattle: A review

Abstract In contrast to intensive dairying practices in many Northern Hemisphere countries, dairy cattle in many countries in the Southern Hemisphere, such as Australia and New Zealand, are grazed outdoors all year round. Outdoor farming has a more favourable welfare image largely because of the freedom of the animals to perform a wide range of species-specific behaviours and possibly because of the perception of less stress and fewer health problems. However, there are a number of practices that have the potential to adversely affect the welfare of cows and calves. This review identifies some of the main animal welfare issues in extensive dairy production. Induced calving can result in high calf mortality rates (rates vary from 0 to 38.5%), particularly if induction occurs prior to 270 days of gestation, and in slower and less efficient uptake of colostral immunoglobulins. Also, the ability of cows to respond to stressors may be impaired due to long-term suppression of endogenous cortisol. Lameness is conservatively estimated to range between 5.5 and 14% of cows, although one estimate is as high as 60% of cows on an annual basis. Lameness may be affected by a number of factors including the type and maintenance of the farm track, the patience of the stockperson in handling the cows and the herd size. Transport of young calves can result in a 50% incidence of bruised stifles and mortality rates greater than 20% following transport, particularly when calves are transported younger than 14 days old. While calves are relatively cold sensitive at birth, both heat and cold can affect the immune system of calves and adversely affect growth rate of neonatal calves. The adult cow is adversely affected more by heat than by cold with effects on both reproduction and lactation; some of the adverse effects on lactation can be obviated by the provision of shade. Nevertheless, a climatic factor often associated with cold is wet weather and this can contribute to lameness. The behaviour of the stockperson (e.g. impatience) may be associated with lameness and there is some limited evidence to indicate that cows that are less fearful of humans may have better milking behaviour and milk production. Tail-docking can adversely affect fly-avoidance behaviour to such an extent that grazing and rumination are disturbed. Disbudding appears to be associated with pain responses that can be obviated by local anaesthesia. Some biotechnological manipulations currently include procedures such as bovine somatotrophin, superovulation, embryo transfer and genetic engineering.

Behavioural responses to humans and the productivity of commercial broiler chickens

The effects of differing degrees of previous exposure to humans on the subsequent behavioural and adrenocortical responses of broiler chickens to approach and restraint by an experimenter were measured in Experiment 1. A higher proportion of birds that had received minimal human contact withdrew as an experimenter approached in a standard test than birds that had received regular human contact (0.77 vs. 0.46, P<0.05). Furthermore, these birds that had received minimal human contact had higher plasma corticosterone concentrations after 12 min of handling than birds in the latter treatment (12.61 vs. 5.40 nmol l−1, P<0.05). The usefulness of behavioural measures as indicators of the birds fear of humans is demonstrated by these results in which handling treatments, designed to affect differentially fear of humans, caused divergence in the behavioural and adrenocortical responses of birds to humans. The major objective of the present study was addressed in Experiment 2, in which the between-farm relationships between the behavioural responses to humans and the productivity of broiler chickens were examined at 22 commercial farms. Some of the behavioural variables were significantly correlated with feed conversion (feed to gain ratio). For example, the average number of birds that approached or remained within 750 mm of an experimenter in a standard test (variable BIRDSs) and the number of birds that remained forward and oriented forward or to the side when an experimenter closely approached in another standard test (REMAINFS) were significantly (P<0.01 and P<0.05, respectively) and negatively correlated with feed to gain ratio (FC) at the farm. The direction of these significant correlations indicate that feed conversion was poor at farms in which birds avoided the experimenter in the two standard tests. The variable BIRDSs was found to predict FC significantly (P<0.02), and this variable accounted for 28% of the variance in feed conversion at the farms. These significant relationships between the behavioural responses of birds to an experimenter and feed conversion suggest that fear of humans may be an important factor limiting the productivity of commercial broiler chickens. The precise mechanism(s) responsible for this inverse fear-productivity relationship in broiler chickens is unclear. However, attention is drawn to the potential for improving the productivity and welfare of commercial broiler chickens by identifying and manipulating those human factors which are influential in commercial units.

Stimulus generalization: the inability of pigs to discriminate between humans on the basis of their previous handling experience

Abstract Two experiments tested whether pigs, under handling conditions similar to those in the commercial industry, could discriminate between two humans on the basis of their previous experience with either one or both of these humans. In the first experiment, pigs were handled by one of two handlers and both handlers used predominantly negative or aversive physical interactions in handling pigs. In the second experiment, all pigs were handled by two handlers; however, the handlers differed markedly in the nature of their handling towards pigs. The handling treatments were imposed over a 6-week period in both experiments. To examine whether stimulus generalization had occurred, the approach behaviour of all pigs to both handlers in a standard human approach test was observed following the handling treatments. In both experiments there were no significant interactions between the handling treatments and the handler in the human approach test. Furthermore, there were no consistent differences between handled pigs in their behavioural responses to familiar and unfamiliar handlers in the test. Therefore, in situations in which pigs are briefly handled by one of two stockpersons in a predominantly negative manner or in which pigs are briefly handled by stockpersons who differ markedly in the nature of their behaviour towards pigs, pigs are likely to exhibit stimulus generalization as measured by their behavioural responses to humans. Thus, in similar handling situations, the behavioural response of commercial pigs to one handler is likely to extent to other humans.

The effects of early contact with humans on the subsequent level of fear of humans in pigs

This study examined the influence of early handling at various ages on the subsequent behavioural responses of pigs to humans. Piglets in handling treatments were handled daily at either 0–3 weeks, 3–6 weeks, 6–9 weeks or 9–12 weeks of age. Handling in these treatments involved individual introduction for 2 min to an experimenter in a small arena. The experimenter squatted during the introduction and attempted to gently pat or stroke the pig whenever it approached closely. Piglets in a fifth treatment received no human contact other than that received during routine husbandry. Piglets in the 0–3 week and 9–12 week handling treatments displayed reduced levels of fear of humans at 18 weeks of age in comparison with those in the non-handling treatment. For example, pigs handled from 0–3 weeks and 9–12 weeks were quicker (P 0.05) treatment effects on the behavioural responses of pigs to humans. As previously found, the results indicate that handling early in life may influence the subsequent behavioural responses of pigs to humans. In the present study, the periods 0–3 weeks and 9–12 weeks were the ones in which handling had the most pronounced effects on behaviour at 18 weeks of age. It is possible that the 0–3 week period was effective since it may represent a sensitive period for socialization in which social contact may influence subsequent social relationships, while the 9–12 week period was effective because it involved the most recent intense handling. However, in contrast to earlier results, those of the present study indicate that the effects of early handling may dissipate or be overriden by the effects of handling later in life.

The effects of fear of humans and pre-slaughter handling on the meat quality of pigs

This study using 90 commercial pigs examined the relationships between the handling that pigs received immediately prior to slaughter and some measures of their meat quality. A number of significant correlations were found between the number of negative interactions that pigs received from the stockperson and subsequent meat quality of the pigs. For example, the number of highly negative interactions received by the pigs was negatively (P < 0.01) correlated with plasma glucose concentrations post-slaughter and positively correlated (P < 0.05) with both post-slaughter plasma lactate concentrations and the light reflectance of the ham. Most of these highly negative interactions were prods with an electric goad. Both the number of interactions by the pig with the experimenter in a standard test used to assess fear of humans and the time taken by the pig to move along the final route to the stunning area were positively correlated (P < 0.05) with the number of highly negative interactions received by the pig prior to slaughter. Regression analysis revealed that the number of highly negative interactions received by the pig, plasma lactate concentration, and the time to physically interact by the pig with the experimenter in the standard test were significant (P < 0.001) predictors of ham lightness. These variables accounted for 18% of the variance in ham lightness. It is concluded that there are some important associations between the behaviour of the stockperson and the muscle physiology of pigs. Although no significant associations were found between stockperson behaviour and ham pH, the correlations between stockperson behaviour, plasma lactate and glucose, and muscle lightness reflect increased muscle glycogenolysis, presumably associated with increased handling stress prior to slaughter. Such results indicate the opportunity to manipulate the behaviour of stockpeople prior to slaughter to improve meat quality.

Effects of grouping unfamiliar adult pigs after dark, after treatment with amperozide and by using pens with stalls, on aggression, skin lesions and plasma cortisol concentrations

The effects of methods, previously shown to reduce aggression, were determined on the number of aggressive interactions, skin lesions and plasma cortisol concentrations following grouping of four unfamiliar, adult ovariectomised pigs. There were four treatments involving 24 pigs in six replicates: (i) Control; (ii) Stall, in which there were four partial stalls used for feeding; (iii) Amperozide, an anti-aggression drug; (iv) Dark in which the pigs were grouped 30 min after sunset. All treatments were in rectangular pens providing a space allowance of 1.4 m2 per pig. Aggressive interactions were observed for 90 min following grouping and for 40-min periods around feeding on the day following grouping and 9 days later. Skin lesions were assessed 3 days after grouping. The spatial use of the pens was determined during a 60 min period between 14:00 and 16:00 h on the day following grouping and 9 days later. Total cortisol concentrations were determined from samples collected during a 75 min period commencing 90 min and 24 h after the start of grouping and total and free cortisol concentrations were determined from nine blood samples collected at hourly intervals on days 8 and 10. Fewer aggressive interactions (P 0.05). However, there were significant positive regressions between aggressive interactions and the number and length of lesions (P < 0.05). There was an acute stress response in the Amperozide treatment 90–165 min after grouping compared with all other treatments (0.001 < P < 0.01) and the magnitude of this stress response raises some welfare concerns on the use of amperozide. Animals in the Stall treatment showed a lower (P < 0.01) total cortisol concentration on day 10 than animals in the other treatments and this indicates a welfare benefit from the provision of stalls.