Abstract: Biological market models explain variability in reciprocity and interchange between groups. In groups with a shallow dominance gradient, grooming will be mostly exchanged for itself (i.e. exchange will occur). In groups with steep dominance hierarchies, interchange is expected: individuals will groom higher ranking individuals to get access to limited resources or commodities such as support in conflicts, and grooming will be traded for these commodities. We examine patterns of reciprocity in grooming and support, and of interchange of grooming for support or for tolerance in six captive groups of bonobos. We test whether differences between groups in patterns of reciprocity and interchange can be attributed to differences in a measure of steepness of dominance hierarchies, which is based on dyadic agonistic interactions. We found that grooming was reciprocal in some, but not all groups. Support was highly reciprocal, but this was a side effect of dominance in most groups. Interchange between grooming and support was observed in some groups. Corroborating earlier findings, this was a side effect of individuals preferring high ranking individuals as grooming and support partners, possibly because these high-ranking individuals provide more efficient support in conflicts. There was no evidence for interchange of grooming for tolerance. Variability in grooming reciprocity was explained by differences in steepness of dominance hierarchies, as predicted by the biological market models. In groups with a shallow dominance hierarchy, grooming was more reciprocal. This was not true for reciprocity in support. There was some evidence that individuals groomed dominants more frequently in groups with a steep dominance hierarchy. The variation in interchange relations between grooming and support did not depend on the steepness of dominance hierarchies. We suggest that grooming in itself is a valuable commodity in bonobos, especially under captive conditions, which can be exchanged reciprocally. Bonobos may interchange grooming for another value equivalent, with food sharing as a very likely candidate. This interchange effects seem more dependent on potential to monopolise food than on steepness of dominance hierarchies per se.

Abstract: Summary The taxonomic status of all equid species is not completely unravelled. This is of practical relevance for conservation initiatives of endangered, fragmented equid populations, such as the Asiatic wild asses (in particular Equus hemionus onager and E. hemionus kulan). In this study, a marker panel consisting of 31 microsatellite loci was used to assess species demarcation and phylogeny, as well as allocation of individuals (n = 120) to specific populations of origin (n = 11). Phylogenetic analysis revealed coalescence times comparable with those previously published from fossil records and mtDNA data. Using Bayesian approaches, it was possible to distinguish between the studied equids, although individual assignment levels varied. The observed results support the maintenance of separate captive conservation herds for E. hemionus onager and E. hemionus kulan. The first molecular genetic results for E. hemionus luteus remained contradictory, as they unexpectedly indicated a closer genetic relationship between E. hemionus luteus and E. kiang holderi compared with the other hemiones.

Abstract: The small Cape mountain zebra population in Gamka Mountain Nature Reserve represents a third of the entire gene pool of this endangered species and is thus vital for it's conservation. Presently, management of this population is largely hands off, with the belief that it will grow to levels which will allow it to form a source for the mixing of mountain zebra stocks in the future. The growth of this population however, has been slow and we investigated the influence of habitat and fire on this growth. Firstly, we used a diffusion model to perform a population viability analysis. This analysis indicated that the population had a low probability of attaining quasi-extinction in the next 50 years (G = 0.0032). However, our findings indicated that less than 30% of the reserve was suitable for mountain zebra and that the preferred habitat would have to be burnt at unnaturally short intervals to sustain the present growth. We therefore argue that the risk of quasi-extinction to this population is greater than predicted and suggest that management options need to be implemented to reduce this risk. These options include; translocation to another protected area; acquisition of adjacent land; burning preferred habitat at unnaturally short intervals; forming a conservancy with adjacent landowners; leasing cultivated land for pasture. We suggest that only the latter two options are likely to stimulate mountain zebra population growth in the short term and that these should receive immediate attention.

Abstract: The aim of this study was to establish some basic facts about weanling horse (Equus caballus) behaviour in a loose housing/paddock environment during winter. The behaviour of 10 foals (seven American Standardbred and three Finnish cold-blooded foals) was observed in a cold loose housing/paddock environment from December 2002 to March 2003. The time budget, circadian rhythm and effect of weather conditions on behaviour were examined. The foals were observed for a total of 23 24-h periods by video recording. The method used was instantaneous sampling (), where the locations of foals were noted at every 15 min along with the behaviour performed at that time. Temperature, humidity and wind speed were recorded three times a day. The foals spent 43.2 +/- 6.6% of the time in the sleeping hall (an insulated building with a deep-litter bed), 51.4 +/- 5.8% in the open paddock and 5.2 +/- 2.7% in the shelter (a two-sided, roofed entrance shelter in front of the sleeping hall). The time spent outdoors was greatest between the hours of 08:00 and 20:00, but the foals spent some time outdoors also at night. They spent most of the day eating hay (27.6 +/- 3.0%) (offered ad libitum), standing (25.5 +/- 2.8%) and resting (32.1 +/- 2.4%). The proportion of locomotive behaviour patterns was 5% of the observations. The foals in this study were able to perform species-specific behaviour patterns (resting, eating, being active) and to follow the natural circadian rhythm of these patterns. The behaviour of the foals did not change much as the temperature dropped from 0 to -20 [degree sign]C. The time spent in the sleeping hall did not increase greatly, nor the time spent eating, resting or lying close to each other (huddling). On the basis of their behaviour, the weanling horses did not seem to suffer from the cold environment.

Abstract: Like most large grazing herbivores, horses select their food based on visual cues, odour, taste, texture, availability and variety. There is relatively little published information about the role of flavour in diet selection by domestic horses in comparison with other domestic and companion animals. However, previous trials investigating effects of diet flavour in stabled horses indicated significant effects on foraging behaviour and selection. In this series of three trials we aimed to determine relative acceptance by presenting flavour preference tests to eight horses. Horses were stabled and fed hay ad lib on trial data collection days plus a standard unflavoured concentrate ration at 7:30 a.m. In Trial 1, 15 flavours were separately presented in standard 100 g cereal by-product meals and the trial was replicated. Quantity consumed, time of completion, partial rejection or refusal were recorded. Order of presentation was determined by a Latin Square design. Trial data were collected on five sampling days, separated by a minimum of 1 day. Horses were presented with six flavoured meals daily; minimum 1 h between the meals. Twelve flavours were universally accepted and of these the eight flavours with fastest mean consumption times (banana, carrot, cherry, cumin, fenugreek, oregano, peppermint and rosemary) were presented in paired preference tests in Trial 2. In Trial 2, all paired combinations of the eight flavours were presented, in two tests per day at noon and 4 p.m. Presentations of the same flavour were separated by at least 1 day. Paired presentations were in 300 g cereal by-product. Presentations were terminated when approximately half of the total amount presented had been consumed. Flavour preferences were expressed as a ratio from 0 (rejection) to 1 (exclusive consumption). Paired flavour preferences produced the following rank order: fenugreek, banana, cherry, rosemary, cumin, carrot, peppermint, oregano. In Trial 3, relative consumption times of mineral pellets flavoured with fenugreek and banana were significantly reduced in comparison with unflavoured pellets. In these short-term trials, flavour had significant effects on diet acceptance, selection and consumption times.