Nutritional Strategies to Improve Efficiency in the Stocker and Feedlot Industries in a Consumer Conscious Market
Biological efficiency potential and nutrient supply synchrony are primary determinants of feed efficiency when converting feed to beef carcass yield. Feedlot diets have historically been formulated to have a minimum roughage inclusion to maintain rumen health and a minimum protein level (crude, metabolizable, or degradable protein) for targeted growth rates. While historically effective, we have asked if poorly digested and increasingly expensive roughage could be eliminated. We have also asked why diets are formulated for protein when calves have specific requirements for AA. When no-roughage diets were formulated to match absorbable AA supply to diet effective energy density (AAEE), net energy equations were found to overestimate energy required for gain and feed efficiency was improved in growing cattle. Recently developed, commercially available in-pen weighing technology offers further opportunity to improve feed efficiency and reduce diet costs by formulating diets to supply absorbable AA equal to requirements based on animal growth rate. Further improvement in efficiency has been demonstrated via selection for efficiency based on residual feed intake (RFI). Our research to date has led us to conclude that nutrient requirement is influenced by RFI phenotype. More accurate estimates of biological energy requirement, real-time growth performance measurement capability, and increased biological efficiency selection can improve post-weaning feed efficiency of cattle to a greater magnitude than generally thought possible, but full potential will not be realized if diet formulations do not support the potential for improvement.
Keywords: Beef, Efficiency, Nutrition