Abstract: Anthropophagic horses have been described in classical mythology. From a current perspective, two such instances are worth mentioning and describing: Glaucus of Potniae, King of Efyra, and Diomedes, King of Thrace, who were both devoured by their horses. In both cases, the horses' extreme aggression and their subsequent anthropophagic behaviour were attributed to their madness (hippomania) induced by the custom of feeding them with flesh. The current problem of 'mad cow' disease (bovine spongiform encephalopathy) is apparently related to a similar feed pattern. Aggressive behaviour in horses can be triggered by both biological and psychological factors. In the cases cited here, it is rather unlikely that the former were the cause. On the other hand, the multiple abuses imposed on the horses, coupled with people's fantasies and largely unconscious fears (hippophobia), may possibly explain these mythological descriptions of 'horse-monsters'.

Abstract: Cognition and perception in horses has often been misunderstood. Not only in the past but even today, people proclaim that horses react only by instinct, that they are just conditioned-response animals, that they lack advanced cognitive ability, and that they have poor visual capabilities (e.g., acuity, color vision, depth perception). Until relatively recently, there was little scientific evidence to address such beliefs. Change, however, is underway as scientific and public interest in all aspects of equine learning and perception intensifies. A review of the scientific literature, as well as practical experience, shows that horses excel at simpler forms of learning such as classical and operant conditioning, which is not surprising considering their trainability when these principles and practices are applied. Furthermore, horses have shown ease in stimulus generalization and discrimination learning. Most recently and unexpected by many, horses have solved advanced cognitive challenges involving categorization learning and some degree of concept formation. A comprehensive understanding of the cognitive and perceptual abilities of horses is necessary to ensure that this species receives proper training, handling, management, and care.

Abstract: Holstein steer calves (n = 32; 156 {+/-} 33.2 kg average BW) were used to evaluate the duration of restraint and isolation stress (RIS) on endocrine and blood metabolite status and the incidence of dark-cutting LM. Calves were blocked by BW and assigned randomly within blocks to one of four stressor treatments: unstressed controls (NS) or a single bout of RIS for 2, 4, or 6 h. Venous blood was collected via indwelling jugular catheters at 40, 20, and 0 min before stressor application and at 20-min intervals during RIS. Unstressed calves remained in their home stanchions and, except for blood sampling, were subjected to minimal handling and stress. Serum cortisol and plasma lactate concentrations were increased (P <0.01) during the first 20 min after RIS application, and remained elevated throughout the 6 h of RIS. Plasma concentrations of glucose and insulin were greater (P <0.05) in RIS calves than in NS calves after 80 and 100 min of stressor application, respectively; however, RIS did not (P >0.80) affect plasma NEFA concentrations. Calves were slaughtered within 20 min of completion of RIS, and muscle samples were excised from right-side LM at 0, 0.75, 1.5, 3, 6, 12, 24, and 48 h after exsanguination for quantifying LM pH, and glycogen and lactate concentrations. The pH of the LM from calves subjected to 6 h of RIS exceeded 6.0, and was greater (P <0.05) at 24 and 48 h postmortem than the pH of NS calves or calves subjected to 2 or 4 h RIS. Muscle glycogen concentrations did not differ (P = 0.16; 25.58, 10.41, 13.80, and 14.41 {micro}mol/g of wet tissue weight for NS and 2-, 4-, and 6-h RIS, respectively), and LM lactate concentrations tended to be lower (P = 0.08) in calves subjected to 6 h of RIS. At 48 h after exsanguination, the LM from calves subjected to 6 h of RIS had more (P <0.05) bound and less (P <0.05) free moisture than did the LM from NS calves or calves subjected to 2 or 4 h of RIS. Additionally, the LM from RIS calves was darker (lower L* values; P <0.05) than the LM of NS calves. Visual color scores for the LM were greatest (P < 0.05) for calves subjected to 6 h of RIS and least (P <0.05) for NS calves. Subjecting lightweight Holstein calves to 6, 4, and 2 h of RIS resulted in six (75%), two (25%), and two (25%) carcasses characteristic of the dark-cutting condition, respectively. There were no dark-cutting carcasses produced from NS calves. Thus, RIS may be a reliable animal model with which to study the formation of the dark-cutting condition. N1 -

Abstract: We studied the natural history and social behavior of Paratemnoides nidificator (Balzan 1888) in a tropical savanna system. Females were responsible for all nymphal care. We observed, for the first time in pseudoscorpions, the occurrence of matriphagy behavior by the offspring. During conditions of food deprivation, the mother went out of the nest and passively awaited the protonymphs' attack, not reacting to the capture nor to the nymphs feeding on her body. We suggest that this extreme form of parental care, matriphagy, can reduce cannibalism among protonymphs and facilitate the evolution of social behavior in pseudoscorpions. RESUMO Nos estudamos a historia natural e o comportamento social de Paratemnoides nidificator (Balzan 1888) na regiao dos cerrados. As femeas foram responsaveis por todo o cuidado as ninfas. Nos observamos, pela primeira vez em pseudoescorpioes, a ocorrencia de matrifagia pela prole. Em condicoes de fome, a mae deixa o ninho e passivamente espera que as protoninfas a ataquem, nao reagindo nem a captura, nem a alimentacao das ninfas sobre seu corpo. Nos sugerimos que esta forma extrema de cuidado parental, matrifagia, possa reduzir o canibalismo entre as protoninfas e assim facilitar a evolucao de comportamento social em pseudoescorpioes.