Infrequent dietary supplementation feeding in beef cattle: animal responses and factors affecting its success.

Abstract Infrequent supplementation (IS; i.e., feeding supplement to animals at frequency less than daily) as opposed to frequent (i.e., daily) could be used as a management tool to improve economic returns of extensive beef production systems by reducing costs associated with the delivery of supplement to cattle. However, previous reports on the effectiveness of IS on production responses in beef cattle are ambiguous and the factors affecting responses to IS by beef cattle are poorly known. The objective of this study was to summarise available data related to the success of IS in beef cattle fed a low quality diet. Additionally, we aimed to identify other potential factors, such as supplement type and composition, forage quality, supplemental degradable intake protein, breed of cattle and environment, which may influence the animal's response to IS. The results of our study suggest that no single factor could fully explain the discrepancies among studies and, therefore, each of these factors should not be treated in isolation. Cattle maintained with IS appear to be more efficient using the urea recycling mechanism to maintain level of ruminal ammonia during the non-supplemental feeding days. Systematic approaches compiling all potential factors affecting responses of beef cattle to IS are required to determine the likelihood of success with IS for a given farming system.