Abstract: In contrast to horses in pastures, it is thought that free-ranging horses do not perform latrine behaviour, i.e. a behavioural pattern whereby the animals graze and defecate in separate areas. However, few studies deal with this particular subject, reporting contrasting conclusions. We hypothesize that horses free-ranging in large heterogeneous areas do not perform latrine behaviour. Thus, we believe that grazing and elimination behaviour are spatially related: where horses graze, they will also defecate. Behavioural data were collected from Konik horses, Haflinger horses, Shetland ponies and donkeys, grazing in different nature reserves (54-80 ha). Data for the different equids were analyzed separately, as well as data for mares and stallions (Konik and donkey stallions only). We investigated the proportion of the number of defecations/urinations while grazing on the total number of defecations/urinations; furthermore, we searched for the sequence of behaviours representing latrine behaviour in the strict sense. Additionally, we analyzed the correlation between grazing behaviour and eliminative behaviour on both vegetation type level and patch level. All the female equids often continued grazing while defecating. During urination, grazing ceases in the majority of instances. Cases where a mare terminated grazing in a certain vegetation type and sward height to eliminate in another vegetation type or in another sward height within the same vegetation type were rarely observed. On the vegetation type level as well as on the patch level, there was a highly significant (P<0.001) positive correlation between grazing time and number of eliminations (or eliminating time). The high values of the correlation coefficients (in case of the defecation variables r ranges between 0.553 and 0.955; in case of the urination variables r ranges between 0.370 and 0.839) illustrate that the spatial distribution of the eliminative behaviour can be explained to a high degree by the spatial distribution of the grazing behaviour. Results in the case of the stallions are preliminary, but indicate the same pattern. Horses, free-ranging in large heterogeneous areas, do not perform latrine behaviour, but defecate where they graze. Possibly, animal density is of major importance to explain this behavioural difference with horses in pastures. We suggest that also spatial vegetation heterogeneity and plant productivity of the grazed area, as well as parasite status of the grazing animals could play a role.

Abstract: It has been suggested that during instrumental learning, animals are likely to react emotionally to the reinforcer. They may in addition react emotionally to their own achievements. These reactions are of interest with regard to the animals' capacity for self-awareness. Therefore, we devised a yoked control experiment involving the acquisition of an operant task. We aimed to identify the emotional reactions of young cattle to their own learning and to separate these from reactions to a food reward. Twelve Holstein-Friesian heifers aged 7-12 months were divided into two groups. Heifers in the experimental group were conditioned over a 14-day period to press a panel in order to open a gate for access to a food reward. For heifers in the control group, the gate opened after a delay equal to their matched partner's latency to open it. To allow for observation of the heifers' movements during locomotion after the gate had opened, there was a 15m distance in the form of a race from the gate to the food trough. The heart rate of the heifers, and their behaviour when moving along the race towards the food reward were measured. When experimental heifers made clear improvements in learning, they were more likely than on other occasions to have higher heart rates and tended to move more vigorously along the race in comparison with their controls. This experiment found some, albeit inconclusive, indication that cattle may react emotionally to their own learning improvement.

Abstract: The cooperative abilities of captive chimpanzees, Pan troglodytes, in experiments do not match the sophistication that might be predicted based on their naturally occurring cooperative behaviours. This discrepancy might partly be because in previous experiments potential chimpanzee cooperators were partnered without regard to their social relationship. We investigated the ability of chimpanzee dyads to solve a physical task cooperatively in relation to their interindividual tolerance levels. Pairs that were most capable of sharing food outside the test were also able to cooperate spontaneously (by simultaneously pulling two ropes) to obtain food. In contrast, pairs that were less inclined to share food outside of the test were unlikely to cooperate. Furthermore, previously successful subjects stopped cooperating when paired with a less tolerant partner, even when the food rewards were presented in a dispersed and divisible form to reduce competition between subjects. These results show that although chimpanzees are capable of spontaneous cooperation in a novel instrumental task, tolerance acts as a constraint on their ability to solve such cooperative problems. This finding highlights the importance of controlling such social constraints in future experiments on chimpanzee cooperation, and suggests that the evolution of human-like cooperative skills might have been preceded by the evolution of a more egalitarian social system and a more human-like temperament.

Abstract: Weaning in suckler calves influences performance in a learning task. The aim of the present study was to investigate whether the improved performance after weaning, including relocation, is due to differences in motivation for the reward or in learning abilities. Forty Aubrac calves were used; half of them were weaned from their dams at around eight months, the other half were weaned one month later. After weaning, calves were housed in groups of four in a new setting. From the day after weaning of the last group of calves, the animals were subjected to two tests: (1) an arena test, (2) a T-maze test where one arm led to either a social or a food reward. The T-maze test consisted of three sessions: in Session 1, trials were conducted until the animal acquired the task (i.e. did not take the unrewarded arm on three consecutive trials); in Session 2, the motivation for the reward was assessed via the walking time of the animal to reach the reward; in Session 3, the place of reward was reversed and the animals were trained until they acquired the new task. Calves weaned for one day explored more (P < 0.05) and had lower heart rates during the arena test (P < 0.05) compared to the ones weaned for one month. During the T-maze test, calves weaned for one month versus one day did not differ in their capacities to learn the initial route (Session 1) or in their motivation for either the social or food reward (Session 2). Calves weaned for one day learned significantly faster (P < 0.05) the reversed route (Session 3) than calves weaned for one month. Hence, the better performances at reversal in the T-maze by calves that have just been weaned cannot be accounted for by a higher motivation for the reward. A better cognitive control of their behaviour due to a lower stress state is suggested by our results.

Abstract: An attempt to replicate Grzimek (1952; Z. Tierpsychol., 27: 330-338) is reported where a Quarter-Horse mare chose between colored and gray stimuli for food reinforcement. Stimuli varied across a broad range of reflectance values. A double-blind procedure with additional controls for auditory, olfactory, tactile, and position cues was used. The subject could reliably discriminate blue (462 nm) vs. gray, and red (700 nm) vs. gray without regard to reflectance (P<0.001), but could not discriminate green (496 nm) vs. gray. It is suggested that horses are dichromats in a manner similar to swine and cattle.