A influência das verminoses no aproveitamento dos nutrientes da dieta por equinos Mangalarga Marchador criados em condições extensivas

Abstract

The horses raised in tropical and subtropical regions are predisposed to infections caused by gastrointestinal parasites and it is suspected that the worm infestation may influence in the digestive efficiency of these animals. However, this effect has not yet been proven. The objective was to evaluate the influence of endoparasites infestation on the digestibility of nutrients of the equine diet and also compare different estimates of consumption by the LIPE indicator. Nineteen mares Mangalarga Marchador, with 3 to 8 years of age and live weight average of 32.55 kg ± 397.16 was not dewormed in the last 12 months, were distributed as the parasitic burden into two groups (V and NV). Group V mares were treated with anthelmintic and Group NV was not. These mares were kept in pasture of Panicum maximum CV. Tanzania, receiving mineral salt and water ad libtum, and concentrated in the ratio of 0.3 to 0.5% of live weight, depending on the body condition of the animals. The experiment lasted 51 days. Two digestibility trials were made: the first to define the initial level of digestibility of animals and the second, 35 days after worming the Group V to check the effect of the dewormed of the animals on the apparent digestibility of nutrients in the diet. Also blood collections were made in the first and second tests of digestibility to evaluate levels of hematocrit, hemoglobin, leukocytes, lymphocytes, eosinophils and monocytes. Consumption, faecal production and the digestibility of each nutrient in the diet were determined using the external indicator LIPE®. For determination of the digestibility of dry matter were held analysis of gross energy, crude protein, neutral detergent fiber, acid detergent fiber, ash, calcium and phosphorus of concentrated and stools. The dry matter intake evaluation of Group V were calculated in association of the LIPE, digestibility of dry matter by mobile bags, in vitro digestibility and with the external indicator Klason lignin, being the three evaluations compared with each other. The data were subjected to analysis of variance and averages were compared by Fisher test for digestibility coefficients, and Tukey test to 5% for the blood parameters and for comparing consumption estimates. There were no differences (p > 0.05) for the apparent digestibility coefficients of nutrients, with the exception of phosphorus, which was best in Group NV, nor in blood parameters evaluated. Dry matter intake by the LIPE, when associated to mobile bags and digestibility in vitro did not show differences (p>0.05), showing the potential to be used for estimating the intake of horses on pasture. Cyathostomine infestation did not alter the apparent digestibility of nutrients in the diet in mares Mangalarga Marchador, in the initial third of gestation supplemented with concentrate.