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Kurvers, C. M. H. C., van Weeren, P. R., Rogers, C. W., & van Dierendonck, M. C. (2006). Quantification of spontaneous locomotion activity in foals kept in pastures under various management conditions. Am J Vet Res, 67(7), 1212–1217.
Abstract: OBJECTIVE: To describe spontaneous locomotion activity of foals kept under various management conditions and assess the suitability of global positioning system (GPS) technology for recording foal activity. Animals-59 foals. PROCEDURES: During the foals' first 4 months of life, 921 observation periods (15 minutes each) were collected and analyzed for locomotion activities. The GPS system was evaluated by simultaneously carrying out field observations with a handheld computer. RESULTS: Foals spent 0.5% of total observed time cantering, 0.2% trotting, 10.7% walking, 32.0% grazing, 34.8% standing, and 21.6% lying down. Total observed daytime workload (velocity x distance) in the first month was approximately twice that in the following months. Locomotion activity decreased with increasing age. Colts had more activity than fillies in certain periods, and foals that were stabled for some portion of the day had compensatory locomotion activity, which was probably insufficient to reach the level of foals kept continually outside. The GPS recordings and handheld-computer observations were strongly correlated for canter, trot, and walk and moderately correlated for standing and lying. Correlation for grazing was low. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that domestically managed foals, when kept 24 h/d at pasture, will exercise at a level comparable with feral foals. High workload during the first month of life might be important for conditioning the musculoskeletal system. The GPS technique accurately quantified canter, trot, and walk activities; less accurately indexed resting; and was unsuitable for grazing because of the wide array of velocities used while foraging.
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Janson, C., & Byrne, R. (2007). What wild primates know about resources: opening up the black box. Anim. Cogn., 10(3), 357–367.
Abstract: Abstract We present the theoretical and practical difficulties of inferring the cognitive processes involved in spatial movement decisions of primates and other animals based on studies of their foraging behavior in the wild. Because the possible cognitive processes involved in foraging are not known a priori for a given species, some observed spatial movements could be consistent with a large number of processes ranging from simple undirected search processes to strategic goal-oriented travel. Two basic approaches can help to reveal the cognitive processes: (1) experiments designed to test specific mechanisms; (2) comparison of observed movements with predicted ones based on models of hypothesized foraging modes (ideally, quantitative ones). We describe how these two approaches have been applied to evidence for spatial knowledge of resources in primates, and for various hypothesized goals of spatial decisions in primates, reviewing what is now established. We conclude with a synthesis emphasizing what kinds of spatial movement data on unmanipulated primate populations in the wild are most useful in deciphering goal-oriented processes from random processes. Basic to all of these is an estimate of the animals ability to detect resources during search. Given knowledge of the animals detection ability, there are several observable patterns of resource use incompatible with a pure search process. These patterns include increasing movement speed when approaching versus leaving a resource, increasingly directed movement toward more valuable resources, and directed travel to distant resources from many starting locations. Thus, it should be possible to assess and compare spatial cognition across a variety of primate species and thus trace its ecological and evolutionary correlates.
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Herholz, C. P., Gerber, V., Tschudi, P., Straub, R., Imhof, A., & Busato, A. (2003). Use of volumetric capnography to identify pulmonary dysfunction in horses with and without clinically apparent recurrent airway obstruction. Am J Vet Res, 64(3), 338–345.
Abstract: OBJECTIVE: To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. ANIMALS: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). PROCEDURE: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11 horses with exacerbated RAO). Expiratory volume and CO2 curves were recorded by use of a computerized ultrasonic spirometer. Volumetric capnograms were plotted, and derived indices were calculated. RESULTS: Dead-space volume (VD) was calculated by use of the Bohr equation (VD(Bohr)) and for physiologic VD (VD(phys)). Ratios for VD(Bohr) to expiratory tidal volume (VT) and VD(phys) to V(T) as well as an index of effective CO2 elimination were significantly different among groups of horses. Age and use of the horses also significantly affected volumetric capnography indices. CONCLUSIONS AND CLINICAL RELEVANCE: Ratios of VD(Bohr) to VT and VD(phys) to VT as well as an index of effective CO2 elimination were sufficiently sensitive measures to distinguish between healthy horses and horses with RAO in remission. To optimize the ability of volumetric capnography indices to differentiate among horses in heterogeneous populations, it is important to account for effects of age and specific use of the horses.
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Goodwin, D., Davidson, H. P. B., & Harris, P. (2007). A note on behaviour of stabled horses with foraging devices in mangers and buckets. Appl. Anim. Behav. Sci., 105(1-3), 238–243.
Abstract: Processed feed for stabled horses is usually presented in buckets or mangers, and is easily and rapidly consumed. Foraging devices based on the Edinburgh foodball can be used to provide part of the ration. Current designs are all placed on the floor, raising concerns regarding ingestion of foreign materials along with the dispensed food. Alternative devices were evaluated, when presented within suitable, clean containers to prolong food-handling times but avoid such issues. In four Latin square designed replicated trials we investigated behaviour of 12 stabled horses with three foraging devices. These were separately presented for 5 min, varied in sensory complexity (round, square, polyhedral) and contained 500 g high fibre pellets. In Trials 1 and 2 six geldings were presented with devices in buckets then mangers. All individuals foraged successfully from at least one device and behaviour was compared. However, all individuals exhibited some frustration while using the devices (either pawing or biting them). Horses frequently removed the devices from the buckets in Trial 1 terminating these sessions. In Trial 2 mean device foraging duration was ranked polyhedral > round > square. Mean pawing rate in Trial 2 was calculated for horses (frequency of pawing per individual/summed duration manipulation and foraging) and was highest with square (0.11, npawers = 6). In Trial 3 six stabled mares were presented with the same foraging devices in mangers. Mean foraging duration with devices again ranked polyhedral > round > square. Mean pawing rate was highest with round device (0.08, npawers = 4). Trial 4 investigated behaviour of six horses when devices initially containing five high fibre pellets became empty. Mean foraging duration with devices ranked round > polyhedral > square. Mean pawing rate was highest with square device (0.11, npawers = 4). All horses foraged successfully from at least one foraging device in buckets and mangers. Devices met initial objectives but the unpredictability of reward suggests a source of frustration and warrants further investigation.
Keywords: Stabled horse; Behaviour; Foraging device; Management; Edinburgh foodball
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Fleurance, G., Duncan, P., Fritz, H., Cabaret, J., Cortet, J., & Gordon, I. J. (2007). Selection of feeding sites by horses at pasture: Testing the anti-parasite theory. Appl. Anim. Behav. Sci., 108(3-4), 228–301.
Abstract: Management of grazed grasslands for production and/or conservation objectives requires a thorough understanding of the choices of feeding sites by herbivores, and of the biological processes involved. Most models of the feeding strategies of herbivores are based on the principle that optimising the intake of energy (or some nutrient) is the primary goal of foragers but other selective forces, such as parasitism, could be important. Gastrointestinal parasites (including cyathostome nematodes) have powerful effects on the fitness of herbivores and may act as a major selection pressure favouring host behaviour that reduces the risk of encountering parasites. Among large herbivores, horses have perhaps the most marked tendency to select particular feeding sites within grasslands. We test here: (1) whether horses select feeding patches with relatively low parasite densities and (2) if their choice is affected by their parasite load. We used 10 two-year old saddle-horses and three periods. In the first period, the horses were under natural parasitism which varied strongly among individuals; in the second period they were all dewormed, and in the third, a sub-set of the horses was experimentally infected with cyathostome larvae. Ninety-eight percent of the infective larvae in the pasture were found <1 m from faeces. The main determinant of the choice of feeding patch by horses was the availability of patches of different parasite risk and grass height. Controlling for availability, the horses used tall grasses (>16 cm) less than expected, whether the grass was contaminated or not, and they selected for short patches >1 m from faeces, where the risk of encountering parasites was low. These results suggest that selection of feeding sites by horses is driven by an interaction between their nutritional and anti-parasite strategies: the horses avoid the patches of tall grass which are generally of low quality and areas contaminated by parasite larvae which leads them to prefer the patches of short grass far from faeces. The parasite status of the horses at the time of the experiment had no effect on their feeding choices. However, before concluding that the challenge by cyathostomes has no effect on the selection of feeding sites in horses, it will be necessary to test whether the history of parasitism of the individuals, rather than the current status, is important.
Keywords: Foraging strategies; Horses; Parasite risk; Patch choice
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Fischhoff, I. R., Sundaresan, S. R., Cordingley, J., Larkin, H. M., Sellier, M. - J., & Rubenstein, D. I. (2007). Social relationships and reproductive state influence leadership roles in movements of plains zebra, Equus burchellii. Anim. Behav., 73(5), 825–831.
Abstract: In animal groups, collective movements emerge from individual interactions. Biologists seek to identify how characteristics of actors in these groups, and their relationships, influence the decision-making process. We distinguished two basic factors determining leadership in group choices: identity and state. We hypothesized that identity is more important to leadership in groups with stable relationships, which permit the development of habitual roles. In groups with fluid membership, particular individuals or subgroups are less likely to emerge as consistent leaders. Instead, we predicted that movement initiation in unstable groups depends on individual state at the time of the decision. We characterized how identity and reproductive state influenced leadership patterns in the movements of plains zebra. As in many other mammals, lactation in this species significantly alters water and energy needs. We investigated leadership in tightly knit harems and loosely bonded herds of multiple harems. Harem females tended to have habitual roles in the initiation of harem movement. In herds, however, we found no consistent leaders among harems. At both levels of social organization, lactation was a key determinant of leadership. In harems, lactating females were more likely to initiate movement than nonlactating females. In turn, harems containing lactating females were more likely to lead herd movements. Thus, we conclude that social relationships and reproductive state together shape the interactions that produce group behaviours. One benefit to lactating females of leading herd movements is preferential access to scarce water. Thus, leadership roles in group decisions may have fitness consequences.
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Dyson, S., & Murray, R. (2003). Pain associated with the sacroiliac joint region: a clinical study of 74 horses. Equine Vet J, 35(3), 240–245.
Abstract: REASONS FOR PERFORMING STUDY: There has been no large study of horses with suspected sacroiliac (SI) joint region pain in which the clinical diagnosis has been supported by either abnormal radiopharmaceutical activity in the SI joint region or by periarticular infiltration of local anaesthetic solution. OBJECTIVES: To describe the clinical features of horses with SI joint region pain, to document the age, breed, sex, discipline, size and conformation of affected horses and to compare these with the author's (SD) normal case population and to document the results of infiltration of local anaesthetic solution around the SI joint region. METHODS: Horses were selected for inclusion in the study based upon the exclusion of other causes of lameness or poor performance, together with clinical signs suggestive of SI joint pain and abnormal radiopharmaceutical activity in the SI joint region and/or a positive response to periarticular infiltration of local anaesthetic solution. RESULTS: Sacroiliac joint region disease was identified in 74 horses between November 1997 and March 2002. Dressage and showjumping horses appeared to be at particular risk (P < 0.001). Affected horses were generally slightly older than the normal clinic population (P < 0.0001), taller at the withers (P < 0.0001) and of greater bodyweight (P < 0.01). There was a significant effect of breed (P < 0.001), with a substantially higher proportion of Warmblood horses (51%) in the SI pain group compared to the normal clinic population (29%). There was no correlation between conformation and the presence of SI joint region pain. The tubera sacrale appeared grossly symmetrical in most (95%) horses. Poor development of the epaxial muscles in the thoracolumbar region and asymmetry of the hindquarter musculature were common. Twenty-six horses (35%) showed restricted flexibility of the thoracolumbar region and 10 (16%) had an exaggerated response to pressure applied over the tubera sacrale. Fourteen horses (19%) were reluctant to stand on one hindlimb for prolonged periods. The majority of horses (75%) had a straight hindlimb flight and only 18% moved closely behind or plaited. In all horses restricted hindlimb impulsion was the predominant feature; invariably this was most obvious when the horse was ridden. Stiffness, unwillingness to work on the bit and poor quality canter were common. Sacroiliac joint region pain was seen alone (47%), or in conjunction with thoracolumbar pain (16%), hindlimb lameness (20%), forelimb lameness (7%) or a combination of problems (10%). Seventy-three horses (99%) had abnormalities of the SI joint region identified using nuclear scintigraphy. Infiltration of local anaesthetic solution around the SI joint region produced profound improvement in gait in all 34 horses in which it was performed. CONCLUSIONS AND POTENTIAL RELEVANCE: Careful clinical examination combined with scintigraphic evaluation of the SI joint region and local analgesia can enable a more definitive diagnosis of SI joint region pain than has previously been possible.
Keywords: Age Factors; Analgesia/veterinary; Anesthetics, Local/pharmacology; Animals; Body Height; Body Weight; Breeding; Female; Forelimb; Gait; Hindlimb; Horse Diseases/*diagnosis/radionuclide imaging; Horses; Lameness, Animal/*physiopathology; Lumbar Vertebrae/physiopathology; Male; Pain/diagnosis/drug therapy/radionuclide imaging/*veterinary; Sacroiliac Joint/*physiopathology; Sacrum/physiopathology
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de Waal, F. B., Uno, H., Luttrell, L. M., Meisner, L. F., & Jeannotte, L. A. (1996). Behavioral retardation in a macaque with autosomal trisomy and aging mother. Am J Ment Retard, 100(4), 378–390.
Abstract: The social development of a female rhesus monkey (Macaca mulatta) was followed from the day of birth until her death, at age 32 months. The subject, born to an older mother, had an extra autosome (karyotype: 43, XX, +18), an affliction that came about spontaneously. MRI scans revealed that she was also hydrocephalic. Compared to 23 female monkeys growing up under identical conditions, the subject showed serious motor deficiencies, a dramatic delay in the development of social behavior, poorly established dominance relationships, and greater than usual dependency on mother and kin. The subject was well-integrated into the social group, however.
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Crowell-Davis, S. L., & Houpt, K. A. (1985). Coprophagy by foals: effect of age and possible functions. Equine Vet J, 17(1), 17–19.
Abstract: In colts and fillies observed from birth to 24 weeks old, coprophagy occurred from Weeks 1 to 19. Its frequency was greatest during the first two months. Coprophagy was rarely observed in mares and stallions. Foals usually ate the faeces of their mother but were observed to eat their own and those of a stallion and another unrelated mare. Urination by the foal occurred before, during or after 26 per cent of the coprophagy incidents. It is hypothesised that foals may consume faeces in response to a maternal pheromone which signals the presence of deoxycholic acid or other acids which the foal may be deficient in and which it may require for gut immuno-competence myelination of the nervous system. Such a pheromone may also serve to accelerate growth and sexual maturation. Coprophagy may also provide nutrients and introduce normal bacterial flora to the gut.
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Corr, J. A. (2004). Nuns and monkeys: investigating the behavior of our oldest old. Sci Aging Knowledge Environ, 2004(41), pe38.
Abstract: The use of nonhuman primates, particularly rhesus macaques (Macaca mulatta), as the best model for human physiological and cognitive aging is broadly accepted. Studies employing nonhuman primates to investigate behavioral changes that may occur with increasing age, however, are not common mostly because of the unavailability of appropriate subjects. Recent longitudinal human studies suggest that individual personality might play a large role in aging “successfully” and in the retention of high levels of cognition into old age. As a result of the demographic trend of increasing numbers of aged monkeys and apes in captivity, an opportunity exists to further investigate behavioral aging using the monkey model.
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