Ingestive behavior and movement patterns of steers grazing sorghum and supplemented with concentrate

Abstract

The present study was developed at the Beef Cattle Laboratory of the Federal University of Santa Maria and evaluated the effect of three levels of concentrate supplementation (S 0.8, S 1.0, and S 1.2, corresponding to 0.8%, 1.0%, and 1.2% of bodyweight, respectively) on the ingestive behavior and movement patterns of 24 steers grazing on sorghum. The experiments were performed using a completely randomized block design in a 3 ? 3 factorial arrangement (three levels of supplementation ?three experimental periods), and the grazing time was evaluated using a 3 ? 24 factorial arrangement (three levels of supplementation ? 24 hours of observation). The steers fed S 0.8 presented longer(P=0.009) grazing time in the morning (241 min day-1) compared to animals fed S 1.2(172 min day-1). The number of bites per feeding station was higher (4.05) during the second experimental period, and the number of bites min-1 increased from 25.4 to 31.4 from the first to the second experimental period. The changes in sward structure during the growth stages of sorghum affected the number of bites per feeding station and the number of bites per minute.