Ordem de carregamento dos ingredientes e tempo de mistura sobre a homogeneidade da dieta de bovinos de corte confinados

Abstract

The mixing process is intended to produce food for the animals in which they are evenly distributed. The correct mixing process produces a uniform feed in a minimum time, with a minimum cost of overload, energy and work. Variation between samples may be expected, but an ideal mix would have minimal variation in total diet composition (TMR). The addition sequence of the ingredients may also determine the dispersion result of the food in the blending process, as well as the type of blender. Knowing the foods you are going to work on is fundamental to building a safe and economically viable diet. More widespread methods, through chemical analyzes and less widespread as Near Infrared Spectroscopy (NIRS) are methodologies that are being used by nutritionists for food knowledge. Factors such as mixing time, overload and maintenance of equipment, order of inclusion of food, can also affect the mixing quality of the diet. Evaluating the homogeneity of the total ration and finding a common denominator is the best guarantee that the cattle in the feedlot system actually feed on the predicted diet, taking into account their nutritional requirements. The inhomogeneity of the feed can lead to economic losses due to the fall in animal performance and accidents due to over dosing of the ingredients and additives contained in the formulation. Metabolic disorders such as acidosis, tympanism, laminitis, and intoxication may occur if animals are selected for food. The objective of this study was to evaluate the homogeneity of the total diet, through the order of loading of the ingredients in the mixing car and the time of mixing of the diet used in a commercial confinement of cattle. The treatments corresponded to two loading orders and two mixing times. Ten samples of the diet in the trough line were collected after each treatment, being MS, PB, EE and NDF the variables of interest analyzed. A second analysis was performed to evaluate if there was an effect of the sample collection order on the nutrient concentration studied. The results showed that for MS, PB and NDF, there was no evidence of differences in the variability between treatments, whereas for EE, a significant effect was observed for the loading time factor For the effect of the order of sampling on the composition of the diet, there were no indications of changes in the composition of the variables analyzed along the trough lines.