Feeding behavior of feedlot Nellore cattle using different protocols of adaptation to high-concentrate diet

Abstract

The objective of this study is to evaluate the effects of adapting feedlot Nellore cattle to a high concentrate diet with different protocols on feeding behavior. The experiment will be designed as a 2 × 2 factorial arrangement of treatments using repeated measures over time, replicated 6 times (4 bullocks/pen), in which 96 24-mo-old bullocks (380 kg) will be used to this experiment. Factors will be the protocols of adaptation and the duration of those protocols, being the treatments: T1 - step up program in 14 days (S14), T2 - feed restriction program in 14 days (R14), T3 - step up program in 21 days (S21) and T4 - feed restriction program in 21 days (R21). Each treatment will have 6 pens, which each will be considered the experimental units. The experimental diets will be fed twice daily (8 a.m. and 3 p.m), and after the periods of adaptation, all treatments will receive the same finishing diet. On the days of each data collection, visual appraisal will be performed every five minutes during 24 hours by six trained people. During the observations, data of time spent eating, ruminating and resting (all expressed in minutes), number of meals, and number of visits to the water trough will be recorded.