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Albright, J. D., Mohammed, H. O., Heleski, C. R., Wickens, C. L., & Houpt, K. A. (2009). Crib-biting in US horses: Breed predispositions and owner perceptions of aetiology. Equine Veterinary Journal, 41(5), 455–458.
Abstract: Reasons for performing study: Crib-biting is an equine stereotypy that may result in diseases such as colic. Certain breeds and management factors have been associated.
Objectives: To determine: breed prevalence of crib-biting in US horses; the likelihood that one horse learns to crib-bite from another; and owner perceptions of causal factors.
Methods: An initial postal survey queried the number and breed of crib-biting horses and if a horse began after being exposed to a horse with this habit. In a follow-up survey, a volunteer subset of owners was asked the number of affected and nonaffected horses of each breed and the extent of conspecific contact. The likelihood of crib-biting given breed and extent of contact was quantified using odds ratio (OR) and significance of the association was assessed using the Chi-squared test.
Results: Overall prevalence was 4.4%. Thoroughbreds were the breed most affected (13.3%). Approximately half of owners believed environmental factors predominantly cause the condition (54.4%) and crib-biting is learned by observation (48.8%). However, only 1.0% of horses became affected after being exposed to a crib-biter. The majority (86%) of horses was turned out in the same pasture with other horses and extent of contact with conspecifics was not statistically related to risk.
Conclusion: This is the first study to report breed prevalence for crib-biting in US horses. Thoroughbreds were the breed more likely to be affected. More owners believed either environmental conditions were a predominant cause or a combination of genetic and environmental factors contributes to the behaviour. Only a small number of horses reportedly began to crib-bite after being exposed to an affected individual, but approximately half of owners considered it to be a learned behaviour; most owners did not isolate affected horses.
Potential relevance: Genetic predisposition, not just intensive management conditions and surroundings, may be a factor in the high crib-biting prevalence in some breeds, and warrants further investigation. Little evidence exists to suggest horses learn the behaviour from other horses, and isolation may cause unnecessary stress.
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Aldezabal, A., & Garin, I. (2000). Browsing preference of feral goats (Capra hircus L.) in a Mediterranean mountain scrubland. J Arid Env, 44.
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Aldridge, B., Lescun, T., & Radcliffe, J. S. (2012). Recent Molecular Advances in Equine Nutrition – from Test Tube to Practice. In K. Krueger, & (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: The use of molecular techniques has increased our understanding of biological systems; in particular how genes and proteins operate within a cell or organ in response to various stimuli. These techniques can be used to study modes of action or mechanisms in disease states, or in response to applied management or nutritional changes. While applied and basic research are often conducted independent of one another, the real advantages to the equine industry will come from the use of molecular techniques to address applied challenges and/or opportunities within the industry. Therefore, the overall goal of our research has been to use basic and molecular tools to investigate modes of action resulting from changes in nutrition or management. We investigated active nutrient transport capacities of the small and large intestine, the effects of feed withdrawal on intestinal transporter gene expression and function, as well as other measurements pertaining to gut health (gut barrier function and gastrointestinal morphology). This novel and thorough approach to characterize sectional differences (fore- and hind- gut) of nutrient absorption has resulted in quantitative measures of active transport capacity for glucose, phosphorus, glutamine, lysine, and di-peptides in the horse. This research demonstrates that by-products of fermentation in the cecum such as microbial proteins and hydrolyzed phytate phosphorus, can be absorbed in the colon. Previously unidentified in the hindgut of the horse, we reported the expression of the di-and tri-peptide transporter, PepT1, as well as the neutral amino acid transporter, ASCT2, and transport of their substrates. We observed that nutrient transporters for glucose (SGLT1), glutamine (ASCT2) and for di-peptides (PepT1) can be regulated by diet, implying biological relevance to feeding management strategies. Feed withdrawal in horses pre- or post-surgery, prior to or during horse shows, during transport, or for other management reason is common. It is therefore important to understand how the removals of nutrients impacts gut health and/or disease susceptibility. The use of molecular techniques has provided a basis for the roles of certain core nutrients during times of feed withdrawal. For example, nutrients such as glutamine play a major role in proliferation and repair in the gut, serve as a major energy substrate, and may provide a means of assessing nutritional stress in the gut. Recent data concludes that following a feed withdrawal, the need for glutamine increases up to 116% in the proximal jejunum, and the gene expression of its transporter (ASCT2) increases by 78%. Additional studies utilizing molecular techniques to address nutritional challenges in the horse include how hormone loss due to ovariectomization impacts the homeostatic regulation of calcium and phosphorus in the horse. To improve nutrition and feeding management practices in horses, knowledge regarding how and where nutrients are absorbed, utilized and regulated under varying physiologic stressors (disease, exercise, reproductive status, etc.) is needed. The integration of applied and basic research facilitates a better and more complete understanding of mechanisms underlying common health and nutritional challenges facing the equine industry.
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Alexander, B. K., & Bowers, J. M. (1969). Social organization of a troop of Japanese monkeys in a two-acre enclosure. Folia Primatol (Basel), 10(3), 230–242.
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Alexander, D. J. (1982). Ecological aspects of influenza A viruses in animals and their relationship to human influenza: a review. J R Soc Med, 75(10), 799–811.
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ALEXANDER, F. (1963). Digestion in the horse. Zool. Garten., , 259–268.
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Alexander, F. (1982). Effect of phenylbutazone on electrolyte metabolism in ponies. Vet. Rec., 110(12), 271–272.
Abstract: Phenylbutazone administered in therapeutic doses to ponies decreased urinary sodium and chloride excretion. The volume and osmolality of the urine was unaffected as was potassium excretion. Faecal excretion of chloride decreased and that of potassium increased, while faecal sodium excretion was unaffected. Plasma pH, bicarbonate and total carbon dioxide decreased after phenylbutazone administration. Packed cell volume, plasma sodium, potassium, carbon dioxide tension and chloride were unchanged.
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Alexander, F. (1978). The effect of some anti-diarrhoeal drugs on intestinal transit and faecal excretion of water and electrolytes in the horse. Equine Vet J, 10(4), 229–234.
Abstract: The effect of morphine, Tinct. opii, loperamide, pethidine and atropine on intestinal transit and the faecal and urinary excretion of water and electrolytes was studied in ponies. The rate of passage of a particulate marker was slowed by morphine, hastened then slowed by loperamide and Tinct. opii, and hastened by atropine. The liquid marker was slowed by Tinct. opii and hastened then slowed by the other drugs. Only loperamide decreased the faecal sodium excretion. This drug also decreased faecal water and weight; it appeared worthy of clinical trial in diarrhoea. Tinct. opii decreased by morphine, pethidine and atropine increased faecal water.
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Alexander, F. (1977). The effect of diuretics on the faecal excretion of water and electrolytes in horses. Br J Pharmacol, 60(4), 589–593.
Abstract: 1. The effect on plasma, urinary and faecal electrolytes of frusemide and hydrochlorthiazide was measured in ponies, mean weight 180 kg. 2. The rapid loss in urine of large quantities of sodium had only a small effect on plasma sodium concentration. 3. Faecal sodium excretion was increased substantially after the administration of frusemide. 4. Frusemide increased faecal potassium during the 48 h following administration and faecal water in the 24/48 h period. It also produced a hypopotassaemia. 5. Hydrochlorthiazide increased faecal chloride during the 24 h after administration. 6. Frusemide increased the intestinal transit time of both liquid (polyethylene glycol) and particulate (Cr2O3) markers.
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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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