Micotoxinas na dieta dos equinos: influência sobre a digestão, o metabolismo e o desempenho

Abstract

The objective was to verify the effect of mycotoxins on the physiological, biochemical and hematological parameters of horses. The research was conducted at School Sergeants of Arms (ESA), in Três Corações, MG. The total experimental period was 40 (forty) days, split into two phases, one pre-experimental of 12 (twelve) days and the experimental phase of 28 (twenty eight) days. Along experimental phase, the animals were homogeneously distributed in a completely randomized design in a split/splot arrangement, with three treatments with four animals each, the animal being the experimental unit. In this phase, a one kg of concentrated meal prepared with 50 ppb or 100 ppb of AFB1 was fed daily to the animals, according to the recommended treatment. During the 4-week duration of the experiment, blood samples were collected once a week to verify animal health by monitoring hematological, renal and hepatic function, by means of the evaluation of hematimetric indices and blood biochemistry. The performance was assessed by the physical exercise effort performed at 21 days of the experimental phase. The exercise consisted of a previous warm-up of 17 (seventeen) min at a trot and followed by three gallops of 450 m / min, with heart rate (HR) monitoring between the gallops. Before the exercise and immediately after the third gallop, the physiological and blood parameters were monitored along of 48 hours after exercise. At the end of the experimental phase, the animals were submitted to the digestion test, using the partial feces collection method, with LIPE® as an indicator. The results of the hematological, biochemical and physiological parameters and the diet digestibility were submitted to analysis of variance (ANOVA) and compared by the Tukey test at 5% of significance. The presence of aflatoxin in the diet influenced white blood cell rates, especially granulocytes, serum creatine kinase activity and alkaline phosphatase (FAL), which presented higher values in the treatment with 100 ppb AFB1. In response to exercise, the presence of AFB1 influenced FAL activity, which presented higher averages in the treatment with 100 ppb, possibly due to the associated hepatotoxic action of mycotoxins in the diets. There was no action of mycotoxins at concentration used in the digestibility of nutrients; however, the presence of mycotoxins in food exposes the animals to continual risk, especially the equines.