Utilization of whole cottonseed in diets with high proportion of concentrate in feedlot lambs: performance, carcass characteristics and meat, ingestive behavior and digestibility of diets.

Abstract

Cottonseed is an ingredient of high interest in ruminant nutrition because of its high content in protein, fiber and energy allowing low cost diet formulation. To evaluate the effects of feeding cottonseed in high-concentrate diets fed to lambs two experiments will be performed. Experiment 1: Sixty-four ram lambs, Dorper X Santa Inês, will be alloted in a randomized complete block design and confined for a period of 56 days. The experimental diets will be isonitrogenous (16% CP) and composed of 90% concentrate and 10% coastcross hay. The levels of cottonseed will be: 0, 7, 14 and 21% (DM basis), corresponding to the experimental diets CA0, CA7, CA14 and CA21, respectively. The objective of experiment 1 will be to determine the effects of using diets with cottonseed on performance, carcass characteristics and feeding behavior. Experiment 2: Eight ram lambs, cannulated in the rumen, will be used to evaluate the diets used in Exp. 1. The variables determined will be: nutrient digestibilities, nitrogen balance and ruminal measures. The experimental design will be a double 4x4 Latin square.