Abstract: A study was made of the behavior of young male Misaki feral horses in the developmental stage, by observing nine of them once a week from January 1988 to December 1996. The relationship between behavior before separation and in the developmental stage was also investigated. This stage begins just after young males separate from their natal band or mothers, and it continues until they start to form harems. The duration of the developmental stage in the study ranged from 0.6 to 3.9 years, depending on the age of the young males at the time of separation. Young males associated with three types of social groups at the beginning of the developmental stage, according to their social groups before separation. These were bachelor groups, harem groups and wandering female groups. During this period, males joined the three groups, mixed sex groups and sometimes were solitary. It was considered that these associations provided a good opportunity for males to acquire different behavioral patterns and experiences before they entered the next stage. Depending on the groups with which they associated, young males that spent more time with bachelor groups had the longest average developmental stage. They associated with harem groups more often during the breeding season and more frequently with other groups or were solitary during the non-breeding season. This may be a transition period because by the end of this stage all males had spent time in solitude before forming their own harem bands.

Abstract: Abstract Conservation agencies within the European Union promote the restoration of traditional land uses as a cost-effective way to preserve biodiversity outside reserves. Although the European Union pursues the integration of the environment into strategic decision-making, it also dictates sectoral policies that may damage farmland biodiversity. We illustrate this point by outlining the socioeconomic factors that allow the persistence of traditional free-ranging horse husbandry in Galicia, northwestern Spain. Free-ranging Galician mountain ponies provide ecological and socioeconomic services including the prevention of forest fires, the maintenance of heathlands and wolves, and the attenuation of wolf-human conflicts. This traditional livestock system may have persisted because it entails negligible costs for farmers. Wolf predation upon Galician mountain ponies does not threaten farmer's economies and seems to be tolerated better than attacks to more valuable stock. Recently, European Union's regulations on animal welfare, carcass management, or meat production put new economic and administrative burdens on farmers, make free-ranging horse rearing economically unsustainable, and incentivize its abandonment. The aim of the European Union to integrate environmental policies may be successful to preserve farmland biodiversity only through careful anticipation of the side effects of apparently unrelated regulations on the fragile equilibrium that sustain traditional land uses.

Abstract: Abstract There is increasing interest in keeping horses in groups, but progress is hampered by a lack of knowledge about which horses can and should be kept together. Therefore, our objective was to investigate the effect of group composition on the occurrence of injuries among horses, the ease of removing horses from groups and horses’ reactivity to a fearful stimulus. Using a matched case control design, 61 groups of horses were studied in Denmark, Norway, Finland and Sweden. They were allocated into groups of similar or different age and sex or where membership changed regularly or remained stable. Injuries were recorded before mixing the horses into treatment groups, the day after mixing and four weeks later. Reactivity of horses to a moving novel object and the behaviour of a horse being removed from its group and the reactions of other group members towards this horse and the handler were evaluated. It was hypothesized that a more socially variable group composition has beneficial effects on behaviour, ease of handling and reducing reactivity whereas frequent changes in group composition has negative consequences, resulting in more injuries. We found that differences in treatment effects were mainly related to breed, rather than group composition. Icelandic horses reacted less to the movement of the novel object (P = 0.007) and approached it more afterwards (P = 0.04). They also had fewer new injuries than warmbloods following mixing (P < 0.001) and fewer than all other groups 4 weeks later (P < 0.01). Most new injuries after mixing were minor and recorded on the horse’s head, chest, hind legs and rump. In conclusion, variations in sex and age composition of the group had little effect on injury level, reactivity and ease of handling compared to the general effect of breed. Concerns about the risk of severe injuries associated with keeping horses in groups are probably overestimated. Thus, we propose that horses can be successfully kept in groups of different sex and age composition.

Abstract: Achieving a high social rank may be advantageous for individuals at high population densities, because dominance status may determine the priority of access to limited resources and reduce individual loss of body mass. The establishment of dominance relationships between individuals involves variable levels of aggressiveness that can be influenced by resource availability. The relationship between social rank and aggressiveness and the impacts of resource abundance on aggressiveness are, however, poorly understood, but may be relevant to understand the mechanisms determining dominance relationships between individuals. We experimentally simulated, in seminatural enclosures, a deterioration of winter forage quality induced by a high-density deer population and examined the effects of (1) social dominance and (2) diet quality on aggressiveness, forage intake and body mass loss of white-tailed deer, Odocoileus virginianus, fawns during two winters. Within diet-quality treatments, fawns were consistently organized into linear hierarchies and showed clear dominance relationships. Dominants initiated more interactions and showed higher aggressiveness than subordinates, but subordinates had higher forage intake than dominants throughout winter. Social rank did not influence cumulative body mass loss of fawns. During both winters, fawns fed the control diet maintained their aggressiveness level, whereas fawns fed the poor-quality diet decreased it. Our experimental approach revealed that white-tailed deer responded to a reduction in winter forage quality by modifying their aggressiveness, indicating that ungulates may show plasticity not only in their foraging behaviour in response to decreased resources but also in their social behaviour.

Abstract: African horse sickness (AHS) is an infectious but no-contagious viral disease of equidae with high mortality in horses. The disease is caused by an arthropod-borne double-stranded RNA virus within the genus Orbivirus of the family Reoviridae transmitted by at least two species of Culicoides. Nine different serotypes have been described. The nine serotypes of AHS have been described in eastern and southern Africa. Only AHS serotypes 9 and 4 have been found in West Africa from where they occasionally spread into countries surrounding the Mediterranean. Examples of outbreaks that have occurred outside Africa are: in the Middle East (1959-1963), in Spain (serotype 9, 1966, serotype 4, 1987-1990), and in Portugal (serotype 4, 1989) and Morocco (serotype 4, 1989-1991). Laboratory diagnosis of AHS is essential. Although the clinical signs and lesions are characteristic, they can be confused with those of other diseases. Several techniques have been adapted for the detection of RNA segments, antibodies and antigen. Two types of vaccines have been described for AHS virus. Attenuated live vaccines (monovalent and polyvalent) for use in horses, mules and donkeys, are currently available, as well as a monovalent, serotype 4, inactivated vaccine, produced commercially but no longer available. New vaccines, including a subunit vaccine, have been evaluated experimentally. In this paper a review of the last AHS outbreaks in Spain, occurring during 1987-1990, and affecting the central and south part of the country, is presented. The role that vaccination played for the control and eradication of the disease, as well as other aspects such as climatological conditions, number of vectors and horse management, are also presented and evaluated.