Avaliação da sensibilidade à insulina em equinos de uso militar

Abstract

The study was carried out to evaluate insulin sensitivity in orses fed diets with high level of soluble carbohydrates. The study was undertaken at the 2nd Cavalary and Guard Regiment Andrade Neves Regiment, situated in Rio de Janeiro, in the year of 2007. Blood samples were taken monthly from fasting horses, and body condition scores (BCS) evaluated during nine consecutive months, from February to October, 2007. Blood was sampled into heparinized and fluorized vacutainer tubes and centrifuged, plasma separated, refrigerated and transported to the EQUILAB Laboratory at the Federal Rural University of Rio de Janeiro, where plasma was stores at -20oC. Plasma was analyzed for glucose spectrophotometrically, and insulin by radioimmunoassay. Basal proxies were calculated for the assessment of insulin sensitivity (RSQUI) and pancreatic beta cell response (MIRG). Feed and hay samples were taken monthly and analyzed for nutrient contend. A glycemic index test was undertaken in a selected group of six horses from the sampled group. No significant relation was found between colic incidence and sex, plasma glucose, insulin, MIRG and RSQUI. Animals that had colic had a trend (P = 0.072) to have a higher BCS, compared to animals without colic during the analyzed period. Horses that had colic had lower body weights than horses without colic (P < 0.05), suggesting that these animals also had lower lean mass, and perhaps more fat. Insulin sensitivity (RSQUI) was higher in the months of higher physical activity. Results of the current study indicate that physical activity is the best prevention for insulin resistance, and, at the same time helps to reduce body fat, and indirectly prevent the occurrence of colic.