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Quiroz-Rothe, E., Novales, M., Aguilera-Tejero, E., & Rivero, J. L. L. (2002). Polysaccharide storage myopathy in the M. longissimus lumborum of showjumpers and dressage horses with back pain. Equine Vet J, 34(2), 171–176.
Abstract: This study was designed to investigate whether horses with clinical signs of back pain due to suspected soft tissue injuries were affected by polysaccharide storage myopathy (PSSM). Diagnosis of PSSM in muscle biopsies obtained from the M. longissimus lumborum of 5 showjumpers and 4 dressage horses with a history of back pain is reported. M. longissimus lumborum biopsies of these horses were characterised histopathologically and in 3/9 cases also by electron microscopy. Observations were compared with M. gluteus biopsies of the same horses, and with M. gluteus biopsies obtained from 6 Standardbreds with recurrent exertional rhabdomyolysis and from 6 healthy trotters. M. longissimus biopsies from horses with back pain showed pathognomonic signs of PSSM, i.e. high glycogen and/or abnormal complex amylase-resistant polysaccharide deposits. Similar features were found in M. gluteus biopsies of the same horses. Sections of horses with rhabdomyolysis had increased PAS stain when compared with healthy horses, but did not show amylase-resistant material. Qualitative observations were corroborated by quantitative histochemistry (optical densities) of sections stained with PAS and amylase PAS. This study demonstrated the presence of PSSM in the M. longissimus of showjumpers and dressage horses with back pain and indicates that epaxial muscle biopsy is an option in diagnosing back problems in horses when clinical examination and imaging techniques do not provide a precise diagnosis.
Keywords: Amylases/analysis; Animals; Back Pain/etiology/*veterinary; Biopsy; Carbohydrate Metabolism, Inborn Errors/diagnosis/pathology/*veterinary; Diagnosis, Differential; Glycogen/analysis; Horse Diseases/*diagnosis/pathology; Horses; Microscopy, Electron; Muscle, Skeletal/pathology; Muscular Diseases/diagnosis/pathology/*veterinary; Polysaccharides/*metabolism; Rhabdomyolysis/diagnosis/pathology/veterinary
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Bouchard, J. (2002). Is social learning correlated with innovation in birds? An inter-and an interspecific test. Master's thesis, Department of Biology McGili University Montréal, Québec, .
Abstract: This thesis focuses on the relationship between innovation and social learning in the foraging context, across and within bird species, using two different sources of data: anecdotal reports from the literature, and experimental tests in the laboratory and the field. In chapter 1, I review the trends in innovation and social learning in the avian literature, and contrast them with trends in mammals, especially primates. In chapter 2, I use anecdotal reports of feeding innovation and social learning in the literature to assess taxonomic trends and to study the relationship between the two traits at the interspecific level. In chapter 3, I investigate the relationship between innovation and social learning at the intraspecific level in captive feral pigeons (Columba livia). Innovation is estimated from the ability to solve an innovative foraging problem, and social learning is measured as the number of trials required to learn a foraging task from a proficient demonstrator. (Abstract shortened by UMI.)
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Jones, J. E., Antoniadis, E., Shettleworth, S. J., & Kamil, A. C. (2002). A comparative study of geometric rule learning by nutcrackers (Nucifraga columbiana), pigeons (Columba livia), and jackdaws (Corvus monedula). J Comp Psychol, 116(4), 350–356.
Abstract: Three avian species, a seed-caching corvid (Clark's nutcrackers; Nucifraga columbiana), a non-seed-caching corvid (jackdaws; Corvus monedula), and a non-seed-caching columbid (pigeons; Columba livia), were tested for ability to learn to find a goal halfway between 2 landmarks when distance between the landmarks varied during training. All 3 species learned, but jackdaws took much longer than either pigeons or nutcrackers. The nutcrackers searched more accurately than either pigeons or jackdaws. Both nutcrackers and pigeons showed good transfer to novel landmark arrays in which interlandmark distances were novel, but inconclusive results were obtained from jackdaws. Species differences in this spatial task appear quantitative rather than qualitative and are associated with differences in natural history rather than phylogeny.
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Zentall, T. R. (2002). A cognitive behaviorist approach to the study of animal behavior. J Gen Psychol, 129(4), 328–363.
Abstract: Traditional psychological approaches to animal learning and behavior have involved either the atheoretical behaviorist approach proposed by B. F. Skinner (1938), in which input-output relations are described in response to environmental manipulations, or the theoretical behaviorist approach offered by C. L Hull (1943), in which associations mediated by several hypothetical constructs and intervening variables are formed between stimuli and responses. Recently, the application of a cognitive behaviorist approach to animal learning and behavior has been found to have considerable value as a research tool. This perspective has grown out of E. C. Tolman's cognitive approach to learning in which behavior is mediated by mechanisms that are not directly observable but can be inferred from the results of critical experiments. In the present article, the author presents several examples of the successful application of the cognitive behaviorist approach. In each case, the experiments have been designed to distinguish between more traditional mechanisms and those mediated by hypothesized internal representations. These examples were selected because the evidence suggests that some form of active cognitive organization is needed to account for the behavioral results.
Keywords: Animals; *Attention; *Behavior, Animal; *Cognition; Learning; *Memory; Social Behavior
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Goto, K., Lea, S. E. G., & Dittrich, W. H. (2002). Discrimination of intentional and random motion paths by pigeons. Anim. Cogn., 5(3), 119–127.
Abstract: Twelve pigeons ( Columba livia) were trained on a go/no-go schedule to discriminate between two kinds of movement patterns of dots, which to human observers appear to be “intentional” and “non-intentional” movements. In experiment 1, the intentional motion stimulus contained one dot (a “wolf”) that moved systematically towards another dot as though stalking it, and three distractors (“sheep”). The non-intentional motion stimulus consisted of four distractors but no stalker. Birds showed some improvement of discrimination as the sessions progressed, but high levels of discrimination were not reached. In experiment 2, the same birds were tested with different stimuli. The same parameters were used but the number of intentionally moving dots in the intentional motion stimulus was altered, so that three wolves stalked one sheep. Despite the enhanced difference of movement patterns, the birds did not show any further improvement in discrimination. However, birds for which the non-intentional stimulus was associated with reward showed a decline in discrimination. These results indicated that pigeons can discriminate between stimuli that do and do not contain an element that human observer see as moving intentionally. However, as no feature-positive effect was found in experiment 1, it is assumed that pigeons did not perceive or discriminate these stimuli on the basis that the intentional stimuli contained a feature that the non-intentional stimuli lacked, though the convergence seen in experiment 2 may have been an effective feature for the pigeons. Pigeons seem to be able to recognise some form of multiple simultaneously goal-directed motions, compared to random motions, as a distinctive feature, but do not seem to use simple “intentional” motion paths of two geometrical figures, embedded in random motions, as a feature whose presence or absence differentiates motion displays.
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Kusunose, R., & Yamanobe, A. (2002). The effect of training schedule on learned tasks in yearling horses. Appl. Anim. Behav. Sci., 78(2), 225–233.
Abstract: Twelve yearlings were divided into two groups and subjected to two different training schedules: (a) 30min of training daily (the daily trained group); and (b) 30min of training for 4 days, followed by a 3-day rest (the intermittently trained group), in order to compare the effect of two training methods on the ability of the horses to learn to be driven and ridden and to respond to the handlers? cues. The length of this experimental training was 17 days. The first step of training was surcingling and proceeded to lunging, to driving from the ground, and finally to being ridden at a trot on a track. Both groups were tested four times during the experimental period when they were at the same stage of training. They were driven and then ridden at a walk by a rider on a specified course and evaluated. The time to complete the course, accuracy of traveling the course, and heart rate during the test were used as the indicators of success in training. In three out of the four tests, the daily trained group tended to move faster and with more accuracy than the intermittently trained group. It would appear that daily training without a long interruption is more effective for yearlings.
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Weaver, A., & de Waal, F. B. M. (2002). An index of relationship quality based on attachment theory. J Comp Psychol, 116(1), 93–106.
Abstract: Two measures are reported of the nature or quality of a mother-offspring (MO) relationship during development using brown capuchin monkeys (Cebus apella) as models. One is a qualitative classification of MO relationships as secure, resistant, or avoidant attachments. The other is an empirical ratio of relative affiliation to agonism called the MO relationship quality, or MORQ, Index. The two methods tapped similar relationship features so relationships high or low of a median split of MORQ values were heuristically labeled secure (n = 22) or insecure (n = 16), respectively. A comparison revealed extensive behavioral differences between secure and insecure MO relationships and suggested MORQ provided an objective, continuous measure of attachment security.
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Watve, M., Thakar, J., Kale, A., Puntambekar, S., Shaikh, I., Vaze, K., et al. (2002). Bee-eaters ( Merops orientalis) respond to what a predator can see. Anim. Cogn., 5(4), 253–259.
Abstract: Two sets of experiments are reported that show that the small green bee-eater ( Merops orientalis, a small tropical bird) can appreciate what a predator can or cannot see. Bee-eaters avoid entering the nest in the presence of a potential nest predator. In the first set of experiments bee-eaters entered the nest more frequently when the predator was unable to see the nest from its position, as compared to an approximately equidistant position from which the nest could be seen. In the second set of experiments bee-eaters entered the nest more frequently when the predator was looking away from the nest. The angle of gaze from the nest was associated significantly positively with the probability of entering the nest whereas the angle from the bird was not. Birds showed considerable flexibility as well as individual variation in the possible methods of judging the predator's position and direction of gaze.
Keywords: Animals; Birds/*physiology; *Predatory Behavior; *Visual Perception
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Ray, E. D., & Heyes, C. M. (2002). Do rats in a two-action test encode movement egocentrically or allocentrically? Anim. Cogn., 5(4), 245–252.
Abstract: Two-action tests of imitation compare groups that observe topographically different responses to a common manipulandum. The general aim of the two experiments reported here was to find a demonstrator-consistent responding effect in a procedure that could be elaborated to investigate aspects of what was learned about the demonstrated lever response. Experiment 1 was a pilot study with rats of a variant of the two-action method of investigating social learning about observed responses. Groups of observer rats ( Rattus norvegicus) saw a demonstrator push a lever up or down for a food reward. When these observers were subsequently given access to the lever and rewarded for responses in both directions, their directional preferences were compared with two 'screen control' groups that were unable to see their demonstrators' behaviour. Demonstrator-consistent responding was found to be restricted to observers that were able to see demonstrator performance, suggesting that scent cues alone were insufficient to cue a preference for the demonstrators' response direction and thereby that the rats learned by observation about body movements (imitation) or lever movement (emulation). Experiment 2 assessed responding on two levers, one that had been manipulated by the demonstrator, and a second, transposed lever positioned some distance away. Demonstrator-consistent responding was abolished when actions were observed and performed in different parts of the apparatus, suggesting that observed movement was encoded allocentrically with respect to the apparatus rather than egocentrically with respect to the actor's body. With particular reference to the influence of scent cues, the results are discussed in relation to the strengths and weaknesses of this and other varieties of the two-action procedure as tests of imitation in animals and human infants.
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Waran, N., Leadon, D., & Friend, T. (2002). The Effects of Transportation on the Welfare of Horses. In The Welfare of Horses (pp. 125–150).
Abstract: Typically, horses are transported many times in their lives, this is with the exception of the horses reared for meat. Although difficult to estimate the extent of the movement of horses worldwide, it is clear that this is a substantial and growing practice. Until recently research into the effects of the different methods of transport (road, sea and air), was limited. This may have been because it was presumed that, because of their financial and emotional value, horses experience higher standards of transportation, than other large domestic animals. The process of transporting horses includes a range of potential Stressors, and there is scientific evidence that many of these can impact upon the welfare of the horse. In this chapter, we examine the effects of the different modes used to transport horses and we offer suggestions where possible for improvements in this practice.
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