Feedlot cattle adaptation phase: principles and updates

The ability of cattle feeders to efficiently adapt animals from high-forage to high-concentrate (finishing) diets, known as the adaptation period, is crucial to overall animal growth performance and health. The adaptation period can be modified by dietary and nutritional management practices, which can either hinder or promote animal health and subsequent growth performance (Lyle et al., 1981; Castillo-Lopez et al., 2014). One of the more common dietary upsets to occur as a result of an inappropriate adaptation is acidosis (Tremere et al., 1968; Elam, 1976); A typical adaptation period in the US, utilized by cattle feeders to limit potential dietary upsets, lasts, on average 21 to 28 days (Brown et al., 2006; Vasconcelos and Galyean, 2007; Samuelson et al., 2016). This adaptation period has been adopted by most producers to allow adequate time for development of lactate-utilizing bacteria (Tajima et al., 2000), ruminal papillae (Schurmann et al., 2014), and animal feeding behavior to