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Casella, S., Fazio, F., Giannetto, C., Giudice, E., & Piccione, G. (2012). Influence of transportation on serum concentrations of acute phase proteins in horse. Research in Veterinary Science, 93(2), 914–917.
Abstract: The modifications of Haptoglobin (Hp), Serum Amyloid A (SAA), Fibrinogen (Fbg) and White Blood Cells (WBCs) were evaluated in 15 Saddle Italian horses. Ten horses were transported covering a distance of about 320 km within 4 h with an average speed of 80 km/h (experimental group) and five horses were not subject to transportation (control group). Blood was collected via jugular venipuncture before the transportation (T0), immediately after the transportation (T1), 12 (T12), 24 (T24) and 48 (T48) hours after the transportation in experimental group and at the same time point in control group. For each parameter statistical analysis of different groups and sampling time was performed using a two-way analysis of covariance, with the data before the transportation (T0) as the covariate, by the GLM procedure of SAS. For all parameters the interaction (Group × Time) was tested and it was resulted no significant. The application of statistical analysis showed significant differences between the control group and horses subjected to transportation (P < 0.01), and the influence of sampling time (P < 0.05) on Hp, SAA and WBCs. These modifications appeared to be innovative showing that equine Hp, generally considered as moderate acute phase protein, increases more rapidly than the SAA after transportation-induced stress.
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Cayado, P., Munoz-Escassi, B., Dominguez, C., Manley, W., Olabarri, B., Sanchez de la Muela, M., et al. (2006). Hormone response to training and competition in athletic horses. Equine Vet J Suppl, (36), 274–278.
Abstract: REASONS FOR PERFORMING STUDY: It is recognised that the amount of psychological stress that an animal encounters determines the degree of response of the hypothalamic-pituitary-adrenal (HPA) axis. In human athletes, the added emotive stress of competition is an important element in the adrenal response. The aim of this study was to examine the effect of show-jumping as well as dressage on stress levels by comparing horses' stress response at a horse show compared to their familiar home. METHODS: Fifty-one horses involved in competition were used. EDTA blood samples were collected before exercise, upon arrived to the schooling area (control), and k over a jump or dressage course. After sampling, plasma was separated and stored at -80 degrees C until determinations of cortisol and ACTH were performed. Fourteen healthy horses not involved in competition were used as control group. RESULTS: Competition induced a significant increase in cortisol and ACTH responses in both, jumping and dressage horses and this effect was more apparent in dressage horses. When horses were most experienced, cortisol and ACTH responses were much lower. CONCLUSION: This study shows that competition elicits a classic physiological stress response in horses and that different training programmes induce different responses. It suggests that horses involved in competition can provide a good model to study the exercise-induced stress response.
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Chapelain, A., & Blois-Heulin, C. (2009). Lateralization for visual processes: eye preference in Campbell"s monkeys ( Cercopithecus c. campbelli ). Anim. Cogn., 12(1), 11–19.
Abstract: Abstract: Brain lateralization has been the matter of extensive research over the last centuries, but it remains an unsolved issue. While hand preferences have been extensively studied, very few studies have investigated laterality of eye use in non-human primates. We examined eye preference in 14 Campbell"s monkeys (Cercopithecus c. campbelli). We assessed eye preference to look at a seed placed inside a tube using monocular vision. Eye use was recorded for 100 independent and non-rewarded trials per individual. All of the 14 monkeys showed very strong preferences in the choice of the eye used to look inside the tube (mean preference: 97.6%). Eight subjects preferred the right eye and six subjects preferred the left eye. The results are discussed in light of previous data on eye preference in primates, and compared to data on hand preference from these subjects. Our findings would support the hypothesis for an early emergence of lateralization for perceptual processes compared to manual motor functions.
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Chapron, G., Kaczensky, P., Linnell, J. D. C., Arx, M., Huber, D., & Andrén, H. (2014). Recovery of large carnivores in Europe's modern human-dominated landscapes. Science, 346.
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Chase, I. D., Bartolomeo, C., & Dugatkin, L. A. (1994). Aggressive interactions and inter-contest interval: how long do winners keep winning? Anim. Behav., 48(2), 393–400.
Abstract: Abstract. Considerable evidence across many taxa demonstrates that prior social experience affects the outcome of subsequent aggressive interactions. Although the 'loser effect', in which an individual losing one encounter is likely to lose the next, is relatively well understood, studies of the 'winner effect', in which winning one encounter increases the probability of winning the next, have produced mixed results. Earlier studies differ concerning whether a winner effect exists, and if it does, how long it lasts. The variation in results, however, may arise from different inter-contest intervals and procedures for selecting contestants employed across previous studies. These methodological differences are addressed through a series of experiments using randomly selected winners and three different inter-contest intervals in the pumpkinseed sunfish, Lepomis gibbosus. The results indicate that a winner effect does in fact exist in pumpkinseed sunfish, but that it only lasts between 15 and 60 min. Based on these results, predictions about the behavioural dynamics of hierarchy formation are discussed, and it is suggested that it may be impossible, in principle, to predict the outcome of dominance interactions between some individuals before they are actually assembled to form a group. Finally, the possible mechanisms underlying the winner effect are explored.
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Chase, I. D., Tovey, C., & Murch, P. (2003). Two's Company, Three's a Crowd: Differences in Dominance Relationships in Isolated Versus Socially Embedded Pairs of Fish. Behaviour, 140(10), 1193–1217.
Abstract: We performed experiments with cichlid fish to test whether several basic aspects of dominance were the same in isolated pairs as in pairs within a social group of three or four. We found that the social context, whether a pair was isolated or within a group, strongly affected the basic properties of dominance relationships. In particular, the stability of relationships over time, the replication of relationships in successive meetings, and the extent of the loser effect were all significantly less in socially embedded pairs than in isolated pairs. We found no significant winner effect in either isolated or socially embedded pairs. These findings call into question many current approaches to dominance that do not consider social context as an important factor in dominance behavior. These findings also cast serious doubt on the validity of empirical and theoretical approaches based on dyadic interactions. Among these approaches are game theoretic models for the evolution of aggressive behavior, experimental designs evaluating how asymmetries in attributes influence the outcome of dominance
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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.
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Chenoweth, P. J., Chase, C. C., Larsen, R. E., Thatcher, M. - J. D., Bivens, J. F., & Wilcox, C. J. (1996). The assessment of sexual performance in young Bos taurus and Bos indicus beef bulls. Appl. Anim. Behav. Sci., 48(3-4), 225–235.
Abstract: Yearling beef bulls, representing different Bos indicus and Bos taurus breeds, were given two sexual performance assessments (libido score, number of services, time to first mount and time of sexual inactivity) at four test periods (January, April, July and October) in 1991 (Trial 1) and 1992 (Trial 2) at the Subtropical Agricultural Research Station, Brooksville, Florida. Breed and test period, as well as their interactions, influenced most results. Sexual performance assessments generally improved with age in Bos taurus breeds, but not in Bos indicus. The temperate Bos taurus breeds (Angus and Hereford) were most sexually active, the tropically adapted Bos taurus breeds (Senepol and Romosinuano) intermediate and the two Bos indicus breeds (Brahman and Nellore x Brahman) were least active. Service rates were generally low. Seasonal patterns in sexual performance were not apparent, with breed and year differences occurring. Although breeds showed consistent test results, the failure of Bos indicus bulls to service in any test, indicates either sexual immaturity, or inadequate procedures for assessment of sexual performance in this breed group.
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Cheung, C., Akiyama, T. E., Ward, J. M., Nicol, C. J., Feigenbaum, L., Vinson, C., et al. (2004). Diminished hepatocellular proliferation in mice humanized for the nuclear receptor peroxisome proliferator-activated receptor alpha. Cancer Res, 64(11), 3849–3854.
Abstract: Lipid-lowering fibrate drugs function as agonists for the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha). Sustained activation of PPARalpha leads to the development of liver tumors in rats and mice. However, humans appear to be resistant to the induction of peroxisome proliferation and the development of liver cancer by fibrate drugs. The molecular basis of this species difference is not known. To examine the mechanism determining species differences in peroxisome proliferator response between mice and humans, a PPARalpha-humanized mouse line was generated in which the human PPARalpha was expressed in liver under control of the tetracycline responsive regulatory system. The PPARalpha-humanized and wild-type mice responded to treatment with the potent PPARalpha ligand Wy-14643 as revealed by induction of genes encoding peroxisomal and mitochondrial fatty acid metabolizing enzymes and resultant decrease of serum triglycerides. However, surprisingly, only the wild-type mice and not the PPARalpha-humanized mice exhibited hepatocellular proliferation as revealed by elevation of cell cycle control genes, increased incorporation of 5-bromo-2'-deoxyuridine into hepatocyte nuclei, and hepatomegaly. These studies establish that following ligand activation, the PPARalpha-mediated pathways controlling lipid metabolism are independent from those controlling the cell proliferation pathways. These findings also suggest that structural differences between human and mouse PPARalpha are responsible for the differential susceptibility to the development of hepatocarcinomas observed after treatment with fibrates. The PPARalpha-humanized mice should serve as models for use in drug development and human risk assessment and to determine the mechanism of hepatocarcinogenesis of peroxisome proliferators.
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Chiandetti, C., Regolin, L., Sovrano, V. A., & Vallortigara, G. (2007). Spatial reorientation: the effects of space size on the encoding of landmark and geometry information. Anim. Cogn., 10(2), 159–168.
Abstract: The effects of the size of the environment on animals' spatial reorientation was investigated. Domestic chicks were trained to find food in a corner of either a small or a large rectangular enclosure. A distinctive panel was located at each of the four corners of the enclosures. After removal of the panels, chicks tested in the small enclosure showed better retention of geometrical information than chicks tested in the large enclosure. In contrast, after changing the enclosure from a rectangular-shaped to a square-shaped one, chicks tested in the large enclosure showed better retention of landmark (panels) information than chicks tested in the small enclosure. No differences in the encoding of the overall arrangement of landmarks were apparent when chicks were tested for generalisation in an enclosure differing from that of training in size together with a transformation (affine transformation) that altered the geometric relations between the target and the shape of the environment. These findings suggest that primacy of geometric or landmark information in reorientation tasks depends on the size of the experimental space, likely reflecting a preferential use of the most reliable source of information available during visual exploration of the environment.
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