Performance of feedlot Nellore cattle fed with rations containing different corn genotypes

Abstract

Of the world's maize production, 70% to 85% is used for animal feed and represents a high-quality energy source. The main corn genotypes are flint corn (high vitreous endosperm), semi-flint corn (medium vitreous endosperm), and semi-dent corn (low vitreous endosperm); as the vitreous in the grain increases, starch degradation decreases. The whole grain and intact matrix protein of corn are resistant to digestion by ruminants because rumen bacteria cannot adhere to them. Some studies have shown that starch degradation is better for corn with low vitreous endosperm; however, in Brazil, most of maize produced is flint corn (high vitreous endosperm). Most farmers use corn grain that is ground and incorporated into the concentrate ration for ruminant feeds without consideration of corn genotype or particle size, which influence rumen fermentation, microbial protein yield, and feed efficiency. This trial was conducted to evaluate the performance of beef feedlot cattle that received rations containing different corn genotypes.