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Milgram, N. W., Head, E., Muggenburg, B., Holowachuk, D., Murphey, H., Estrada, J., et al. (2002). Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy. Neurosci Biobehav Rev, 26(6), 679–695.
Abstract: The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition.
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McGreevy, P. D., Cripps, P. J., French, N. P., Green, L. E., & Nicol, C. J. (1995). Management factors associated with stereotypic and redirected behaviour in the thoroughbred horse. Equine Vet J, 27(2), 86–91.
Abstract: A greater knowledge of the effect of management factors is required to investigate the ontogeny of abnormal behaviour in the stabled horse. A postal survey of racehorse (flat) trainers yielded information about 22 yard and management factors. The relationship of the factors to the prevalence of abnormal behaviour was analysed by logistic regression. Management factors related to the time spent in the stable showed the strongest associations with stereotypic behaviour. The risk of horses performing abnormal behaviour increased: 1) as the amount of forage fell below 6.8 kg/day, 2) when bedding types other than straw were used, 3) when the total number of horses on the yard was fewer than 75, 4) in association with box designs that minimised contact between neighbouring horses, 5) when hay, rather than other types of forage, was used.
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McBride, S. D., & Long, L. (2001). Management of horses showing stereotypic behaviour, owner perception and the implications for welfare. Vet. Rec., 148(26), 799–802.
Abstract: A telephone survey was conducted of 100 racing stables, 100 riding schools and 100 competition establishments (8,427 horses in total) to determine what management practices were being applied to horses showing stereotypic behaviour, and to determine the underlying reasons for them by assessing the perceptions and opinions of the people working with the horses. The results indicated that horse owners are concerned about stereotypic behaviour, first, because it reduces the performance of the animal (31, 30 and 27 per cent of the owners of racing stables, riding schools and competition establishments respectively), secondly, because it has adverse clinical effects on the horse (52, 55 and 56 per cent), and thirdly, because it reduces the monetary value of the animal (45, 59 and 31 per cent). The belief that these behaviours are learnt or copied also affects the management of affected horses: they are not allowed on to the premises by 4, 32 and 17 per cent of owners of racing stables, riding schools and competition establishments, respectively; attempts are made to remove the causal factors of the stereotypy by 35, 43 and 36 per cent; the behaviours are physically prevented by 77, 67 and 79 per cent, and the affected horses are kept separate from other horses by 39, 30 and 48 per cent.
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Nicol, C. J., Potzsch, C., Lewis, K., & Green, L. E. (2003). Matched concurrent case-control study of risk factors for feather pecking in hens on free-range commercial farms in the UK. Br Poult Sci, 44(4), 515–523.
Abstract: 1. The aim of the study was to compare the management and husbandry of free-range flocks in the UK where feather pecking was either present (case) or absent (control). 2. One hundred flocks were enrolled into a concurrent case-control study: 50 where birds had recently started feather pecking, and 50 matched control flocks where birds of the same age had not started feather pecking. 3. Information was obtained from a detailed interview with the flock manager, and by direct inspection of the flock, house and range. 4. Initial univariate analyses revealed that case flocks were more likely to comprise ISA Brown than Lohmann, were more likely to be restricted from litter areas to prevent floor eggs, and were less likely to use the outside range. 5. Cluster analysis indicated that feather pecking was not associated with any particular husbandry system. 6. The only influential risk factor significant in the multivariable conditional logistic regression analysis was use of the outdoor range. The risk of feather pecking was reduced 9-fold in flocks where more than 20% of birds used the range on sunny days (odds ratio = 0.12). Use of the range was positively associated with the presence of trees and/or hedges on the range.
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Pere, M. C. (1995). Maternal and fetal blood levels of glucose, lactate, fructose, and insulin in the conscious pig. J. Anim Sci., 73(10), 2994–2999.
Abstract: To study nutrition and metabolism in the fetal pig, a chronic catheterization method was developed that allows blood sampling in arteries and veins, at both the umbilical and uterine sources, in the conscious, unstressed animal. A catheter was inserted in the fetal aorta through a femoral artery, and another one was introduced in the umbilical vein. A catheter was put in a femoral artery of the sow so that its end was in the abdominal aorta. A fourth catheter was placed in a uterine vein draining the fetoplacental unit studied. This procedure was applied to 18 Large White primiparous sows at 99 d of gestation. Blood samples were drawn simultaneously using the four catheters before a meal at 103 d of pregnancy, and glucose, insulin, lactate, and fructose were determinated. Glycemia was 2.5 times higher in the sow than in the fetus. The extraction coefficient of glucose by the fetus amounted to 14% of the umbilical supply. The insulin level in the fetal pig was very low ( < 5 microU/mL). Lactate and fructose seemed to originate from the placenta. Blood lactate was 2.6 times lower in the sow than in the fetus, and its extraction coefficient by the fetus amounted to 8%. Fructose in the fetal blood was 2.3 times higher than that of glucose. Fructose was not utilized by the pig fetus. The present results obtained in the fetal pig are comparable to the conclusions drawn from studies with other species.
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Palme, R. (2005). Measuring fecal steroids: guidelines for practical application. Ann N Y Acad Sci, 1046, 75–80.
Abstract: During the past 20 years, measuring steroid hormone metabolites in fecal samples has become a widely appreciated technique, because it has proved to be a powerful, noninvasive tool that provides important information about an animal's endocrine status (adrenocortical activity and reproductive status). However, although sampling is relatively easy to perform and free of feedback, a careful consideration of various factors is necessary to achieve proper results that lead to sound conclusions. This article aims to provide guidelines for an adequate application of these techniques. It is meant as a checklist that addresses the main topics of concern, such as sample collection and storage, time delay extraction procedures, assay selection and validation, biological relevance, and some confounding factors. These issues are discussed briefly here and in more detail in other recent articles.
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Bayly, K. L., Evans, C. S., & Taylor, A. (2006). Measuring social structure: A comparison of eight dominance indices. Behav. Process., 73(1), 1–12.
Abstract: Measurement of social status is an important component of many behavioural studies. A variety of techniques have been developed and adopted, but while there have been some analyses of index properties using simulated data, the rationale for selecting a method remains poorly documented. As a first step in exploring the implications of index choice, we compared the characteristics of eight popular indices by applying each to the same data set from interactions between male fowl Gallus gallus, the system in which social hierarchies were first described. Data from eight social groups, observed over four successive breeding seasons, were analysed to determine whether different indices produced consistent dominance scores. These scores were then used in tests of the relation between social status and crowing to explore whether index choice affected the results obtained. We also examined the pattern of dominance index use over the last decade to infer whether this has likely been influenced by tradition, or by taxa of study animal. Overall agreement among methods was good when groups of birds had perfectly linear hierarchies, but results diverged when social structure was more complex, with either intransitive triads or reversals. While all regression analyses revealed a positive relationship between dominance and vocal behaviour, there were substantial differences in the amount of variance accounted for, even though the original data were identical in every case. Index selection can hence perturb estimates of the importance of dominance, relative to other factors. We also found that several methods have been adopted only by particular research teams, while the use of others has been taxonomically constrained, patterns implying that indices have not always been chosen solely upon their merits. Taken together, our results read as a cautionary tale. We suggest that selection of a dominance index requires careful consideration both of algorithm properties and of the factors affecting social status in the system of interest.
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Dreschel, N. A., & Granger, D. A. (2009). Methods of collection for salivary cortisol measurement in dogs. Horm. Behav., 55(1), 163–168.
Abstract: Salivary cortisol has been increasingly used as a measure of stress response in studies of welfare, reaction to stress and human–animal interactions in dogs and other species. While it can be a very useful measure, there are a number of saliva collection issues made evident through studies in the human and animal fields which have not been investigated in the canine species. Collection materials and the volume of saliva that is collected; the use of salivary stimulants; and the effect of food contamination can all dramatically impact cortisol measurement, leading to spurious results. In order to further examine the limitations of the collection method and the effects of collection material and salivary stimulant on salivary cortisol levels, a series of clinical, in vitro and in vivo studies were performed. It was found that there is a large amount of inter- and intra-individual variation in salivary cortisol measurement. Beef flavoring of collection materials leads to unpredictable variability in salivary cortisol concentration. Using salivary stimulants such as citric acid also has the potential to affect cortisol concentration measurement in saliva. Hydrocellulose appears to be a useful collection material for salivary cortisol determination. Recommendations for collection materials and use of salivary stimulants are presented.
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Dargatz, D. A., & Traub-Dargatz, J. L. (2004). Multidrug-resistant Salmonella and nosocomial infections. Vet Clin North Am Equine Pract, 20(3), 587–600.
Abstract: Nosocomial infections are a serious threat to optimum patient care. In addition, nosocomial infections can have far-reaching consequences for the hospital personnel and the financial aspects of the hospital. Nosocomial infections with Salmonella spp have been described among hospitalized equine populations more frequently than any other agent. Salmonella spp associated with hospitalized equids often possess more antimicrobial resistance determinants than do Salmonella spp isolated from healthy horses in the general population. There is little evidence to suggest that resistant salmonellae are more virulent than nonresistant forms. MDR forms of Salmonella complicate the selection of appropriate antimicrobials when they are indicated, however. Furthermore, the use of some antimicrobials may apply selection pressure toward enhanced ability of MDR Salmonella to colonize equine patients. Further research should help to elucidate the risky uses of antimicrobials in the hospital setting and define the role of disinfectants and treatments such as NSAIDs in the ecology of MDR forms of nosocomial infections, including Salmonella. In the meantime, thoughtful selection of when and how to use antimicrobials in equine patients, together with deliberate selection of which antimicrobials to use based on monitoring data and other factors, such as safety and spectrum, is advised.
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Alexander, F. (1970). Multiple fistulation of the horse's large intestine. Br. Vet. J., 126(11), 604–606.
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