Time required for ruminal bacteria to adapt to changes in the diet of confined cattle: Review

Abstract

The system of production in animals’ feedlot is an excellent strategy for periods of food scarcity and lack of space. In feedlot, concentrated diets with high levels of fast-digesting carbohydrates are used. This review was carried out with the objective of addressing the effect of feedlot diets on the ruminal bacterial population in cattle finished in feedlot. Ruminal bacteria respond rapidly to dietary changes, since they reproduce at intervals of less than 60 minutes. The time of colonization of ruminal bacteria indicates the speed that adhere and penetrate into the food. Rumen microorganisms can be associated with food particles at different times. The particle size of food is one of the important factors for degradation, since it determines the attack surface for microorganisms and directly influences the time of colonization of the food. There is a linear relationship between the body size of the animals and the rumination rate, evidencing that it relates the size of the rumen or digestive tract with the body weight of the animals. Restriction and ladder adaptation protocols are the most used by nutritionists in beef cattle in feedlot The inclusion of additives and probiotics is a valid strategy to improve utilization, as long as it is used at appropriate levels. To minimize the negative effects of changes in diets, it is necessary to gradually adapt the ruminal microbiota, either by the adaptation protocols by ladder or by restriction. Both protocols typically improve health and maximize the performance of animals with 14 days of adaptation.