Abstract: Cerebral lateralization, i.e. hemispheric asymmetries in structure and function, relates in many species to a preference to attack from their left. Lateralization increases cognitive capacity, enabling the simultaneous processing of multiple sources of information. Therefore, lateralization may constitute a component of fighting ability (Resource Holding Potential), and/or influence the efficiency of information-gathering during a contest. We hypothesized that lateralization will affect contest outcome and duration, with an advantage for more strongly lateralized individuals. In 52 dyadic contests between weight-matched pigs (Sus scrofa; n = 104; 10 wk age), the direction of orientation towards the opponent was scan sampled every 10 s. Laterality indexes (LI) were calculated for the direction and strength of lateralization. Up to 12.5% of the individuals showed significant lateralization towards either the right or left but lateralization was absent at the population level. In line with our hypothesis, animals showing strong lateralization (irrespective of direction) had a shorter contest duration than animals showing weak lateralization. Winners did not differ from losers in their strength or direction of lateralization. Overall the results suggest that cerebral lateralization may aid in conflict resolution, but does not directly contribute to fighting ability, and will be of value in the study of animal contests.

Abstract: In most cases, the social organisation of each of the seven species of Equidae existing today outside captivity is either territorial or non-territorial. The striking differences found between these two types of organisation in the social grouping and bonds, mating behaviour, leadership and dominance hierarchies of the animals are examined. It is thought that the non-territorial species show a less primitive type of organisation than the territorial animals. Infant Equidae are precocious animals and are able to follow their dams soon after birth. They stay close by their dams and travel with the herd from an early age and are therefore classified as “followers”, in contrast to the species which have a period of hiding after birth. Dams recognise their foals immediately after birth, whereas it takes 2 or 3 days for a foal to form an attachment to its dam. Being in close proximity to their dams, foals are able to nurse frequently and, unless artificially weaned, a foal will nurse until its dam foals again. Foals start to graze during their first week and as they grow older they spend more time grazing and less time nursing and resting. It is normal for foals to be corprophagic until one month old, and this provides them with bacteria essential for the digestion of fibre. Play behaviour is solitary in very young foals, but after 4 weeks of age, foals play together, with male foals playing more than females and showing more aggressive, fighting movements in play.

Abstract: Housing conditions for horses impose various levels of confinement, which may compromise welfare. Lying behaviour and activity can be used as welfare indicators for domestic animals and rebound behaviour suggests a build-up of motivation resulting from deprivation. The objective of this study was to determine if activity and lying behaviour of horses are affected by housing conditions and to investigate the occurrence of rebound behaviour after release from confinement. Eight horses were subjected, in pairs, to each of four experimental treatments; paddock (P), fully stabled (FS), partly stabled (PS) and yard (Y). Each horse received 6 days acclimatisation prior to the 24 h recording period. Time spent in lying and activity were electronically recorded using a tilt switch and motion sensor connected to a data logger worn on the horse's left foreleg. Time spent active during the first 5 min of release from stable to paddock in the PS treatment (days 1 and 5) and at the same time of day in the P treatment was used as a measure of rebound behaviour. Effect of housing conditions on total time spent active was highly significant (FS = 123 s, PS = 158 s, Y = 377 s, P = 779 s, P < 0.001). Housing conditions did not significantly affect total time spent lying (P = 0.646). Horses were significantly more active, compared with baseline paddock behaviour, on release from stabling on both days 1 (P = 0.006) and 5 (P = 0.025) of PS treatment. These results suggest that activity patterns of horses, but not lying behaviour, are affected by the housing conditions tested and that rebound activity occurs in horses after a period of confinement.

Abstract: Domestic horses are faced with social challenges throughout their lives due to limitations in social contact, space restrictions and frequent changes in social companionship. This is in contrast to natural conditions where horses live in relatively stable harem bands. Currently, little is known about how repeated regrouping affect horse behaviour and welfare, and it is unknown whether horses may adapt to regrouping. In this study, we aimed to investigate the effects of an unstable group structure, caused by weekly regroupings, on behaviour and frequency of injuries in young horses. Forty-five horses were included in the study and were randomly assigned to the treatments; Stable (S; seven groups of three horses) or Unstable (U; eight groups of three horses). The experimental period lasted 7 weeks, during which horses in Stable groups remained in the same group, whereas one horse was exchanged between Unstable groups every week. The groups were kept in 80m×80m grass-covered enclosures and were fed additional roughage on the ground daily. Social interactions were recorded in Unstable groups immediately after each regrouping (30min), and in both Stable and Unstable groups on day 1, 3 and 6 after each regrouping (2×20min/group/day). Injuries were scored by the end of the experimental period. The level of aggression shown by horses in Unstable groups immediately after regrouping was not affected by week (F5,35=0.42, P=0.83), indicating that horses neither habituated, nor sensitized, to repeated regrouping. Compared to horses in Stable groups, more agonistic behaviour was shown by horses in Unstable groups (i.e. non-contact agonistic; F1,65=5.60, P=0.02), whereas there was no treatment effect on other variables. The level of play behaviour appeared, however, to be more variable in Unstable groups. There was a significant effect of week on the level of contact agonistic interactions as well as greeting behaviour, due to a high occurrence in weeks 4-6. Non-contact agonistic interactions constituted the major part of agonistic interactions (66%). Possibly as consequence, no serious injuries were registered and there was no treatment effect (U=184; P=0.11). We conclude that the behaviour of young horses is affected by group management, and that horses appear not to adapt to weekly regroupings.

Abstract: Social learning in 11 human-raised capuchin monkeys (Cebus apella) was investigated using an artificial fruit that was designed as an analogue of natural foraging problems faced by primates. Each subject observed a human model open each of 3 principal components on the fruit in 1 of 2 alternative ways (“morphs”). The capuchin monkeys reproduced, to differing extents, the alternative techniques used for opening 1 component of the task (poking vs. pulling while twisting out a pair of smooth plastic bolts) but not the other 2. From the subjects' actions on the bolt latch, independent coders could recognize which morph they had witnessed, and they observed a degree of matching to the demonstrator's act consistent with simple imitation or object movement reenactment (A learns from watching B how an object, or parts of an object, move). Thus, these capuchins were capable of more complex social learning than has been recently ascribed to monkeys. (PsycINFO Database Record (c) 2016 APA, all rights reserved)