|
Steelman, S. M., Michael-Eller, E. M., Gibbs, P. G., & Potter, G. D. (2006). Meal size and feeding frequency influence serum leptin concentration in yearling horses. J. Anim Sci., 84(9), 2391–2398.
Abstract: Energy is an essential nutrient for all horses, and it is especially important in performance horses, pregnant and lactating mares, and young growing horses. A negative energy balance in horses such as these may result in unsatisfactory performance, decreased fertility, or slow growth. Therefore, ensuring adequate energy intake is an important aspect of the nutritional management of the equine. This study was undertaken to investigate the effects of feeding large, carbohydrate-rich, concentrate meals on the satiety-inducing hormone, leptin. Three groups of yearling horses were rotated through 3 feeding schedules in a replicated 3x3 Latin square design. Horses were fed 2, 3, or 4 times per day (2x, 3x, and 4xfeeding schedules, respectively), each for a period of 11 d, with the total amount of daily feed held constant. Horses were weighed and BCS was determined on the first day of each period. Blood samples were collected before the morning meal on d 1, 4, and 7 of each period. Additionally, blood was sampled for the last 24 h of the 2xand 4xdietary periods. Neither weight nor BCS changed during the study (P = 0.99 and P = 0.28, respectively). Both mean and peak plasma glucose were greatest in 2xhorses (P < 0.05), as were mean areas under the curve. Serum leptin concentration increased in 2xhorses (P < 0.05), but not in horses fed 3 or 4 times daily. Leptin was elevated in horses with greater BCS (P < 0.05) and increased steadily throughout the study (P < 0.05). Data from the 24-h collection indicated that 2xhorses had fluctuations in leptin production throughout the day (P < 0.05), whereas horses fed 4 times daily did not. Overall, this study indicates that feeding horses 2 large concentrate meals daily can increase mean serum leptin concentrations and may cause fluctuations in leptin production over a 24-h period. This departure from baseline leptin concentration has the potential to affect appetite, along with numerous other physiological processes.
|
|
|
Rizzolatti, G., Fogassi, L., & Gallese, V. (2001). Neurophysiological mechanisms underlying the understanding and imitation of action. Nat Rev Neurosci, 2(9), 661–670.
Abstract: What are the neural bases of action understanding? Although this capacity could merely involve visual analysis of the action, it has been argued that we actually map this visual information onto its motor representation in our nervous system. Here we discuss evidence for the existence of a system, the ‘mirror system’, that seems to serve this mapping function in primates and humans, and explore its implications for the understanding and imitation of action.
|
|
|
Warneken, F., & Tomasello, M. (2009). Varieties of altruism in children and chimpanzees. In Trends in cognitive sciences (Vol. 13, pp. 397–402). Elsevier Science,.
Abstract: Recent empirical research has shed new light on the perennial question of human altruism. A number of recent studies suggest that from very early in ontogeny young children have a biological predisposition to help others achieve their goals, to share resources with others and to inform others of things helpfully. Humans nearest primate relatives, such as chimpanzees, engage in some but not all of these behaviors: they help others instrumentally, but they are not so inclined to share resources altruistically and they do not inform others of things helpfully. The evolutionary roots of human altruism thus appear to be much more complex than previously supposed.
|
|
|
Merl, S., Scherzer, S., Palme, R., & Möstl, E. (2000). Pain causes increased concentrations of glucocorticoid metabolites in horse feces. J Equine Vet Sci, 20(9), 586–590.
Abstract: The concentration of 11,17-dioxoandrostanes (11,17-DOA), a group of cortisol metabolites, was measured using enzyme immunoassay in fecal samples of horses experiencing painful episodes. One group of horses consisted of 10 stallions castrated (samples were collected daily for 10 days); the other group was made up of 29 horses which were brought to an animal hospital because of signs of colic (samples were collected twice daily for six days). Before castration, median concentrations of 10.5 nmol/kg feces were measured. On days 1 and 2 after castration, median 11,17-DOA values increased up to 26.2 and 50.0 nmol/kg feces, respectively, and decreased thereafter to levels lower than at the beginning of the sampling period. High variations were measured between individual cases of colic. In animals with colic, all horses excreted more than 33 nmol 11,17-DOA/kg feces for various periods. The highest concentration measured was 885 nmol/kg feces. One animal out of the 29 colic horses did not show any clinical signs of pain upon arrival in the hospital. The 11,17-DOA values were below 17 nmol/kg feces in all those samples. From this data we conclude, that the concentration of 11,17-DOA in feces is a parameter for painful situations that have occurred one or two days earlier.
|
|
|
Rosati, A. G. (2017). Foraging Cognition: Reviving the Ecological Intelligence Hypothesis. Trends in Cognitive Sciences, 21(9), 691–702.
Abstract: What are the origins of intelligent behavior? The demands associated with living in complex social groups have been the favored explanation for the evolution of primate cognition in general and human cognition in particular. However, recent comparative research indicates that ecological variation can also shape cognitive abilities. I synthesize the emerging evidence that ?foraging cognition? ? skills used to exploit food resources, including spatial memory, decision-making, and inhibitory control ? varies adaptively across primates. These findings provide a new framework for the evolution of human cognition, given our species? dependence on costly, high-value food resources. Understanding the origins of the human mind will require an integrative theory accounting for how humans are unique in both our sociality and our ecology.
|
|
|
Houpt, K. A., Zahorik, D. M., & Swartzman-Andert, J. A. (1990). Taste aversion learning in horses. J. Anim Sci., 68(8), 2340–2344.
Abstract: The ability of ponies to learn to avoid a relatively novel food associated with illness was tested in three situations: when illness occurred immediately after consuming a feed; when illness occurred 30 min after consuming a feed; and when illness was contingent upon eating one of three feeds offered simultaneously. Apomorphine was used to produce illness. The feeds associated with illness were corn, alfalfa pellets, sweet feed and a complete pelleted feed. The ponies learned to avoid all the fees except the complete feed when apomorphine injection immediately followed consumption of the feed. However, the ponies did not learn to avoid a feed if apomorphine was delayed 30 min after feed consumption. They could learn to avoid alfalfa pellets, but not corn, when these feeds were presented with the familiar “safe foods,” oats and soybean meal. Ponies apparently are able to learn a taste aversion, but there were constraints on this learning ability. Under the conditions of this study, they did not learn to avoid a food that made them sick long after consumption of the food, and they had more difficulty learning to avoid highly palatable feeds.
|
|
|
Chase, I. D., Tovey, C., Spangler-Martin, D., & Manfredonia, M. (2002). Individual differences versus social dynamics in the formation of animal dominance hierarchies. Proc. Natl. Acad. Sci. U.S.A., 99(8), 5744–5749.
Abstract: Linear hierarchies, the classical pecking-order structures, are formed readily in both nature and the laboratory in a great range of species including humans. However, the probability of getting linear structures by chance alone is quite low. In this paper we investigate the two hypotheses that are proposed most often to explain linear hierarchies: they are predetermined by differences in the attributes of animals, or they are produced by the dynamics of social interaction, i.e., they are self-organizing. We evaluate these hypotheses using cichlid fish as model animals, and although differences in attributes play a significant part, we find that social interaction is necessary for high proportions of groups with linear hierarchies. Our results suggest that dominance hierarchy formation is a much richer and more complex phenomenon than previously thought, and we explore the implications of these results for evolutionary biology, the social sciences, and the use of animal models in understanding human social organization.
|
|
|
Hunter, L., & Houpt, K. A. (1989). Bedding material preferences of ponies. J Anim Sci, 67(8), 1986–1991.
Abstract: The bedding preferences of ponies were determined using video recordings of nighttime (1900 to 0700) behavior of individually housed ponies. The ponies' behavior each minute was recorded to determine time budgets. In Exp. I, preference for bedding was determined using three mares, three stallions and two geldings given access to bedded and unbedded areas in a box stall. The ponies spent more time (66%) on the bedded area and were never observed lying on the unbedded areas. In Exp. II, three mares and six stallions were given access to a box stall, one side of which was bedded with wood shavings and the other with straw. Although some individual animals preferred one bedding over the other, neither form of bedding was preferred consistently. Time budgets in Exp. II were similar on both bedding materials. The ponies spent 12% of their nighttime lying, 2% walking, 35% eating and 50% standing inactively. Some ponies had a relatively strong preference for bedding, but the type of bedding preferred varied with the individual animal. Some individual ponies had no clear preference, but instead had a side or position preference
|
|
|
Fabrega, H. J. (2006). Making sense of behavioral irregularities of great apes. Neurosci Biobehav Rev, 30(8), 1260–73; discussion 1274–7.
Abstract: Psychopathology, mental illness, and psychiatric treatment are concepts relevant to modern medicine and medical psychology and replete with cumbersome intellectual and literary baggage. They bear the imprint of suppositions, world views, and general beliefs and values exemplified in the science, history, and general culture of Anglo European societies. The study in higher apes of phenomena addressed by such concepts raises conceptual dilemmas, usually termed speciesism and anthropomorphism, not unlike those encountered in comparative human studies of similar phenomena across cultures and historical periods, namely, ethnocentrism and anachronism. The authors' synthesis of literature and their analysis of the implications of higher ape psychopathology represent an epistemically compelling account that broadens the scope of the comparative study of behavioral irregularities, a topic that provides a different slant for examining challenging questions in evolutionary biology and primatology, such as cognition, self awareness, intentional behavior, culture and behavioral traditions, social intelligence, sickness and healing, and altruism. Theoretical and empirical study of this topic expands formulation and can help provide informative answers about human evolution as well as essential features of human psychiatric syndromes, with potential practical implications. The study of psychopathology of higher apes and other non human primates represents an appropriate focus for neuroscience and bio-behavioral sciences.
|
|
|
Provenza, F. D. (1996). Acquired aversions as the basis for varied diets of ruminants foraging on rangelands. J. Anim Sci., 74(8), 2010–2020.
|
|