Abstract: The colours of the horses have long been a subject of interest to owners and breeders of horses as well as to scientists. Though, the colour of horses has little to do with its performance, it is a primary means of identification and also the first indicator of questionable parentage. Probably the ancestral colour of the horse was a black-based pattern that provided camouflage protection against predators. Horse colours are mostly controlled by genes at 12 different loci. The three basic colours of horses are black, bay and chestnut. The genetic control of the basic colours of horses resides at two genetic loci, namely Extension (E) and Agouti (A) loci. Among the basic colours bay is dominant to black and both are epistatic to chestnut. Dilution of basic colours of horses as a result of four colour dilution genes such as cream dilution, dun, silver dapple and champagne resulted in extensive array of possible colours of horses. The most widespread and familiar of the horse colour dilution gene is the one that produces the golden body colour and are called as palomino or buckskin based on the colour of the points. The grey coat colour is due to the presence of dominant gene (G) at the grey locus. Grey is epistatic to all coat colour genes except white and a grey horse must have at least one grey parent. Roan is due to a dominant gene (Rn) at roan locus and this combines with any base colour to produce the various shades of roan pattern. White coat is due to a single dominant gene (W) and it is epistatic to the genes controlling all other colours. White marking in the face and legs are due to genetic and non-genetic factors. Several genes are involved in producing white markings. During recent years, comparative genomics and whole genome scanning have been used to develop DNA tests for different variety of horse colours. Molecular genetic studies on coat colour in horses helped in identification of the genes and mutation responsible for coat colour variants. In future, this will be applied to breeding programmes to reduce the incidence of diseases and to increase the efficiency of race horse population.

Abstract: It is advantageous to identify individuals who are likely to behave fairly and those who are not. This ability to judge others’ fairness seems important for social species to interact or cooperate with their partners. Domestic horses (Equus caballus) have lived with humans for over five thousand years, hence they might have developed sensitivity to human personality. In the present study, we investigated whether horses would discriminate between a person who behaved fairly and a person who behaved unfairly. Specifically, we asked whether horses show a preference for the former. We tested 12 horses (11 thoroughbred and 1 Anglo-Arabian horses) at the horseback-riding club of Kyoto University. They were divided into 6 pairs which consisted of a participant and a partner. A participant was picketed between two polls next to a partner at the hoof washing place. Each horse put his/her mouth in an actor’s hand when the actor (an unfamiliar person) stood in front of them, and then received food from the actor. A fair actor always behaved fairly and gave a small quantity of hay (low-value food) to both of them in return for the task. An unfair actor always behaved unfairly, giving a small quantity of hay to the participant in return for the task, but always giving a piece of carrot (high-value food) to the partner in return for the task. Both actors always stood in front of the partner first, so the partner always did the task and received food from the actor before the participant. Finally, the participant was offered a piece of carrot by the two actors. The participant indicated which offer was accepted by stretching toward the chosen actor. The latter then moved the hand forward to allow the participant to take the food while the other actor’s hand withdrew. The orders (1st or 2nd) and the positions (left or right) of the two actors varied pseudo-randomly across trials. The color of the clothes of the two actors (white or black) was counterbalanced between sessions. We conducted 8 sessions, consisting of 8 experimental trials, across which the actors maintained their respective roles (fair or unfair) of the fair and unfair person. Furthermore, the two actors switched roles across sessions so that they played both roles the same number of times. One session was run per day. If horses can discriminate between fair and unfair people and show a preference for the former, they should choose the former significantly more often than the latter when both actors offered food. The participants showed no overall preference for accepting food from either actor. However, three of six participants showed a side preference. The result of the present study suggests that horses are insensitive to humans’ fairness. Horses may not have expectations about fair treatment.

Abstract: The ecology of Rhodococcus (Corynebacterium) equi in soil was studied on a horse-breeding farm. R. equi was cultured from soil at a depth of 0, 10, and 20 cm on the six sites of the farm at monthly intervals for 10 months from March to December of 1983. The highest numbers of R. equi were found in the surface soil. The mean number of bacteria in soil samples at every depth increased remarkably from 0 or 10(2) to 10(4) colony-forming units (CFU) g-1 of soil in the middle of April, and later decreased gradually. R. equi inoculated into six soil exudate broths prepared from surface soils at separate sites yielded suspensions with different optical densities, indicating differences in growth. The distribution of serotypes in the soil was similar to that in the horses on the farm. These findings indicated that R. equi could multiply in the soil and flourish in the cycle existing between horses and their soil environment.

Abstract: REASONS FOR PERFORMING STUDY: One cause of overstrain injury to the superficial digital flexor tendon (SDFT) in horses is the force loaded on the SDFT during repeated running. Therefore, decreasing this force may reduce SDFT injury. It has been reported that strain on the SDFT decreases with a toe-wedge shoe. Uphill courses are used for training of racehorses, and the angle of hoof-sole to the horizon during uphill running is similar to that of the toe-wedge shoe. OBJECTIVES: To determine the effects of uphill exercise on the force on the SDFT during trotting and cantering. METHODS: Arthroscopically implantable force probes (AIFP) were implanted into the SDFT of the left or right forelimb of 7 Thoroughbred horses and AIFP output recorded during trotting and cantering on a treadmill inclined at slopes of 0, 3 or 8%, and then 0% again. Superficial digital flexor tendon force was calculated as a relative value, with the amplitude of AIFP output voltage at initial 0% slope equal to 100. RESULTS: Out of 14 sets of experiments, AIFP data were analysed successfully in 9 at the trot, in 3 at the canter in the trailing forelimb on a slope of 3 and 8%, and in 2 at the canter in the leading forelimb on a slope of 3%. Increasing the incline from 0-8% tended to decrease peak force in the SDFT at the trot, and in the trailing forelimb at the canter. However, force in the SDFT was unchanged in the leading forelimb at the canter on the 3% incline. CONCLUSIONS: The force in the SDFT trotting or cantering uphill is unchanged or lower than that loaded at the same speed on a flat surface. Because at similar speeds the workload for uphill exercise is greater than on the flat, uphill running increases exercise intensity without increasing force in the SDFT. POTENTIAL RELEVANCE: Uphill exercise may reduce the risk of SDFT injury as both running speed and SDFT force are decreased on an incline as compared to the flat, even when exercise intensity is the same. Further study is needed to confirm these findings at canter in a larger population of horses.