Evaluation of supplementation plans for suckling beef calves managed on tropical pasture

Abstract

This study assessed the effects of different amounts of supplement on the productive performance, nutrional caracteristics and behaviour of suckling beef calves, as well as on the productive performance of their dams on tropical pastures. Forty-four male Nellore beef calves with an average age of 120 days and an initial average body weight (BW) of 145±3.7 kg and their respective dams, with an average BW of 449±6.9 kg, were used. The amounts of supplement evaluated were as follows: 0 = calves received only mineral mixture ad libitum; 3, 6, and 9 = calves received 3, 6, or 9 g kg-1 BW of supplement, respectively, containing 250 g CP kg-1 (as-fed). The experimental design was completely randomized. A positive linear effect (P < 0.01) was observed in the intakes of dry matter and organic matter, and a cubic effect (P < 0.07) was observed for the intake of neutral detergent fiber corrected for ash and protein. There was quadratic effect (P < 0.06) for total digestibility of neutral detergent fiber. A cubic effect (P < 0.01) was observed for the calves' performance. However, the calves' supplementation did not affect the milk yield and performance (P ? 0.21) of their dams. The supplementation decreased grazing time (P < 0.01) but did not influence suckling time (P ? 0.59). It is recommended supplying of supplement containing 250 g CP kg-1 (as-fed) in amount 6 g kg-1 BW to suckling beef calves managed in tropical pasture. Supplementation of suckling beef calves increases the intake of dry matter, decreases grazing time and forage intake. However, it does not affect the suckling time and productive performance of their dams.