Nutritional balance, performance, bone parameters, economics and meat quality of Nellore submitted or not to phosphorous supplementation during feedlot

Abstract

Dietary phosphorus requirements for feedlot cattle may be smaller than those required by the National Research Council (NRC ). On the other hand, phosphorus consumed in excess is excreted primarily through the feces and urine of animal , accumulates in the soil and can cause eutrophication of water resources, in addition to bringing economic losses due to wastage of this mineral resource. There is no scientific evidence , both from a nutritional standpoint or clinicopathologic, justifying the use of phosphorous supplementation for beef cattle feedlot receiving diets with a high proportion of concentrate. Because it is a nonrenewable resource, its high cost and its ability to environmental contamination , this study makes it necessary for the problems related to phosphorous supplementation in Brazilian feedlots. For both, will run a test field with the Nelore cattle subjected to confinement and receiving high grain diets with or without supplemental phosphorous . Fecal and urinary excretion of phosphorus, weight gain, bone parameters and meat quality of animals tested and the final cost of supplementation will be evaluated. (AU)