Abstract: Epinephrine and norepinephrine plasma levels were assessed in dogs in relation to paw preference following an immune challenge with rabies vaccine. The results showed that both catecholamines increased after the vaccine administration, confirming the main role of the sympathetic nervous system in the modulation activity between the brain and the immune system. Moreover, ambidextrous dogs showed a significantly higher increase of epinephrine levels 8 days after immunization with respect to right- and left-pawed dogs, suggesting that the biological activity of this molecule could be key for a different immune response with regard to laterality.

Abstract: This study investigated drinking behaviour of unhandled, semi-feral Dartmoor ponies. Aspects studied were drinking behaviour, latency to drink from novel unfamiliar drinkers after transport, preferences for different types of artificial water drinkers, effects of mixing with unfamiliar ponies and group size, on drinking behaviour, and the effect of a simulated market on the latency to drink. Ponies were tested in groups of three or six animals, or as individuals in test pens that were equipped with three water drinkers: bucket, automatic drinking bowl, flowing water trough. Behaviour was recorded using time-lapse video. An individual pony drank on average 10 l per day. Ponies also drank, but at a lower rate, during the night. The latencies to drink after 4.5 h of transport showed large variation, but most ponies drank within the first hour after being transported (all groups 80.5 ± 32.94 min, mean ± SEM). In the individual choice tests, the preferred drinkers were the bucket and the flowing water trough, but not the automatic drinking bowl (drinking time 25.2 ± 4.66, 11.5 ± 4.26, 2.4 ± 2.23 min for bucket, trough and bowl respectively, mean ± SEM; paired t-tests, bowl versus other drinkers, all tests p < 0.02). A possible reason for the avoidance of the automatic bowl was the noise it made when filling. After mixing a group of three ponies with a group of three unfamiliar animals, the ponies did not express their individual drinker preferences anymore. The use of the previously preferred bucket decreased significantly and the use of the initially, non-preferred, bowl increased significantly. This was likely caused by the fact that ponies were either intentionally or accidentally obstructing drinkers in certain areas of the pen and unfamiliar ponies did not want to push past them. In the simulated market, the differences in latencies to drink between ponies in the home pen and market groups did not reach significance. No significant effect of group size (groups of three versus six ponies) on drinking behaviour was detected. The results have implications for situations where only automatic water bowls are provided, such as during pony sales at livestock markets. Preventing ponies from expressing their drinking choice, either by offering non-preferred drinkers or by mixing with unfamiliar animals, could adversely affect their welfare especially if this happens in conjunction with other stressful events such as transport and markets, and potentially weaning.

Abstract: Observational field studies were conducted on two remote populations of feral horses in Australia to determine whether lateralization is a characteristic of Equus caballus as a species or results from handling by humans. Group 1 had been feral for two to five generations and Group 2 for 10–20 generations. In both groups, left-side biases were present during agonistic interactions and in reactivity and vigilance. Therefore, as in other vertebrates, the right hemisphere appears to be specialized to control agonistic behaviour and responses to potential threats. The leftwards bias was stronger in measures of behaviour involving more aggression and reactivity. Preferences to place one forelimb in front of the other during grazing were also determined. No population bias of forelimb preference was found, suggesting that such limb preferences present in domestic horses may be entrained. Since stronger individual limb preferences were found in immature than in adult feral horses, limb preference may be modified by maturation or experience in the natural habitat. Stronger limb preference was associated significantly with elevated attention to the environment but only in younger feral horses. No sex differences in lateralization were found. The findings are evidence that horses show visual lateralization, as in other vertebrates, not dependent on handling by humans. Limb preference during grazing, by contrast, does appear to depend on experience.

Abstract: Operant conditioning and two choice preference tests were used to assess the motivation of horses to be released from straight and from box stalls. The motivations for food, a companion, and release into a paddock were compared when the horses had to work for each commodity at increasing fixed ratios of responses (panel presses) to reward in an equine operant conditioning stall. The motivation for food (mean ± SEM = 258 ± 143) responses was much greater than that for either release (38 ± 32) from a straight stall into a large paddock alone or into a small paddock with another horse (95 ± 41) (P = 0.04). When given a two choice preference test between exercise on a treadmill for 20 min or returning to their box stalls, eight of nine horses chose to return to their stalls. In a two choice preference test six of eight horses in box stalls chose to be released into a paddock alone. Horses were given a series of two choice preference tests to determine how long they preferred to be in a paddock. After 15 min in the paddock the horses were re-tested, but all chose the paddock when released into a paddock with three other horses. They were retested every 15 min until they chose to return to their stalls. They chose to stay out for 35 ± 6 min when other horses were in the paddock but for only 17 ± 2 min when they would be alone. When deprived of stall release for 48 h the horses chose to remain in the paddock with other horses for 54 ± 6 min, but showed no compensatory behavior when they were alone (duration chosen = 16 ± 4 min). These findings indicate that horses are not strongly motivated to exercise alone and will choose not to endure forced exercise on a treadmill. The social context of voluntary exercise is important; horses are willing to stay out of their stalls longer if other horses are present and will show compensatory behavior only if other horses are present. These finding have implications for optimizing turnout time for stalled horses.

Abstract: A preference test was used to demonstrate that gilts have the ability to associate two sets of neutral cues with two different periods of confinement and water deprivation and to anticipate the long-term consequences of their choice in the test. Twelve gilts housed in two large, straw-bedded pens were trained to go to two sets of 12 crates, positioned on each side of a choice point, for feeding twice a day. Following initial training, the two sets of crates were marked with contrasting visual patterns and the patterns were associated with either 30 min (`short' confinement) or 240 min (`long' confinement) of confinement in the crates after entry. During 16 days of preference testing, the gilts were sent alternately to one side or the other in the mornings and allowed to choose in the afternoons. Eight gilts chose the short confinement side more often, two, the long confinement side more often and two, each side an equal number of times, indicating that most gilts learned the association and preferred to be released shortly after feeding. However, gilts still chose the long confinement side on occasion, suggesting that they did not find 240 min of confinement very aversive. When the gilts were sent to the crates in the morning, their behaviour indicated that they expected to be released or confined depending on which crate they were in. The cognitive abilities of animals with respect to perception of time and anticipation of future events have important implications for their welfare. This study demonstrates that methods can be developed to ask animals about such things.