Abstract: The Swedish riding horse population includes about 6000 broodmares and 150 breeding stallions. The overall breeding goal is to produce riding horses competitive in several disciplines, i.e. dressage as well as showjumping and eventing. The effectiveness of this multi-purpose objective was studied in alternative strategies for selecting stallions and mares as candidate dams for them. The alternative selection strategies for stallions included 1-stage (conformation), 2-stage (conformation and performance test) and 3-stage (conformation, performance test and competition results at advanced levels) selection schemes. The mare selection schemes included the corresponding 1- and 2-stage selection schemes. The results clearly showed the 2-stage selection procedure to be most efficient, especially for stallions. It is important that the intensity in selection after the performance test is kept high. Differences in defining the breeding objective are less important, provided the selection is based on a performance test including both dressage and jumping. According to the results, the development of the Swedish performance testing scheme, in which now only 30% of the tested stallions are selected for breeding, seems justified. In mare selection schemes, performance tests also seem to be justified, especially if jumping ability is to be improved. Differences between field and station tests are only minor and since the volume of testing can be much higher in the field this would allow a much stronger selection and should thus be preferred.

Abstract: Changes in populations of several ungulate species in the Serengeti-Mara region of East Africa over the past 30 years suggest several hypotheses for their regulation and coexistence. Recent censuses in the 1980s have allowed us to test the hypotheses that: (1) there was competition between wildebeest (Connochaetes taurinus) and Thomson's gazelle (Gazella thomsoni). This predicted that gazelle numbers should have declined in the 1980s when wildebeest were food limited. Census figures show no change in gazelle numbers between 1978 and 1986, a result contrary to the interspecific competition hypothesis; (2) wildebeest and African buffalo (Syncerus caffer) populations were regulated by intraspecific competition for food. Since both populations reached food limitation in the 1970s, the hypothesis predicted that the populations should have been stable in the 1980s. The results confirm these predictions for wildebeest and the buffalo population in the Mara reserve. In the Serengeti the buffalo population declined 41% over the period 1976-1984. The decline was not evenly distributed over the park, some areas showing an 80-90% decline, others no change or an increase in numbers. The decline was associated with proximity to human habitation; (3) an outbreak of the viral disease, rinderpest, in 1982 may have been the cause of the drop in buffalo population. Blood serum samples to measure the prevalence of antibodies were collected from areas of decreasing, stable and increasing populations. If rinderpest was the cause of decrease there should be a negative relationship between the prevalence of rinderpest and the instantaneous rate of increase (r). The results showed no relationship. We conclude that rinderpest was not the major cause of the drop in buffalo numbers. Elephant (Loxodonta africana) numbers dropped 81% in Serengeti in the period 1977-1986. In the Mara there was little change. The evidence suggests that extensive poaching in northern and western Serengeti during 1979-1984 accounted for the drop in both elephant and buffalo numbers.

Abstract: In a trial of cage designs for laying hens, eggs were discovered in dust baths where access was restricted by a closed door during the normal laying period (08:00-13:00 h). Observations showed that the hens in these dust bath treatments had developed methods of opening the doors in order to lay in the baths. Three different methods of opening were observed. An average time of 34.4 min was spent attempting to open the doors before access was finally achieved. This implies a strong nesting motivation in these hens. The proportion of eggs laid in the dust baths increased (with occasional fluctuations) over a 24-week period. Door opening is likely to have initially developed in one individual in each cage through a trial and error basis, and then have been learned by cage mates through imitation. The speed and efficiency of door opening was not found to increase with experience or time.

Abstract: Abstract 10.1002/ajp.1350200409.abs Instead of close and differentiated relationships among adult females, the accepted norm for savanna baboons, groups of Drakensberg mountain baboons (Papio ursinus) showed strong affiliation of females towards a single male. The same male was usually the decision-making animal in controlling group movements. Lactating or pregnant females focused their grooming on this “leader” male, producing a radially patterned sociogram, as in the desert baboon (P. hamadryas); the leader male supported young animals in the group against aggression and protected them against external threats. Unlike typical savanna baboons, these mountain baboons rarely displayed approach-retreat or triadic interactions, and entirely lacked coalitions among adult females. Both groups studied were reproductively one-male; male-female relationships in one were like those in a unit of a hamadryas male at his peak, while the other group resembled the unit of an old hamadryas male, who still leads the group, with a male follower starting to build up a new unit and already monopolizing mating. In their mountain environment, where the low population density suggests conditions as harsh for baboons as in deserts, adults in these groups kept unusually large distances apart during ranging; kin tended to range apart, and spacing of adults was greatest at the end of the dry, winter season. These facts support the hypothesis that sparse food is responsible for convergence with hamadryas social organization. It is suggested that all baboons, though matrilocal, are better categorized as “cross-sex-bonded” than “female bonded”.

Abstract: In summary, horses spend 60% or more of their time eating when grazing or when feed is available free choice. Grasses are their preferred food, but they supplement the grass with herbs and woody plants. Sweetened mixtures of oats and corn are the most preferred concentrate. Horses can increase or decrease the time spent eating and amount eaten to maintain caloric intake. Their intake is stimulated by drugs such as diazepam and by the presence of other horses. Horses stop eating when gastric osmolality increases; increases in plasma osmolality, protein, and glucose accompany digestion. Foals eat several times an hour and begin sampling solid food at the same time that their dam is eating. Several areas of particular importance to the equine industry have not been investigated. These areas include the effect of exercise on short- and long-term food intake and the influence of reproductive state on the feeding of mares.