Estratégia de suplementação de novilhas nelore no período de transição águas-seca

Abstract

Effect of different supplementary strategies for cattle on performance, carcass and meat quality and economic viability with supplementation. Two hundred Nellore heifers were used, distributed in a completely randomized design. The treatments consisted of providing different supplementary sources at the levels: SP1- protein supplement with 240 g protein kg-1 de DM of (control), offered at 4 g kg-1 of BW during all the experimental period; SP2- protein supplement with 240 g protein kg-1 of DM at 4 g kg-1 of BW for 28 days and protein-energy supplement with 120 g protein kg-1 of DM provided at 8 g kg-1 of BW for 28 days and protein-energy supplement with 120 g protein kg-1 of DM offered to 12 g kg-1 body weight (BW) for 28 days; SP3 - Protein supplement with 240 g protein kg-1 of DM offered at 4 g kg-1 of BW for 56 days and protein-energy supplement with 120 g protein kg-1 of DM offered at 12 g kg-1 of BW for 28 days; SP4- Protein-energy supplement with 120 g protein kg-1 of DM of offered at 4 g kg-1 of BW for 28 days and protein-energy supplement with 120 g of protein kg-1 of DM offered at 8 g kg-1 of BW for 28 days and protein-energy supplement with 120 g protein kg-1 of DM offered at 12 g kg-1 of BW for 28 days; SP5- Protein-energy supplement containing 180 g protein kg-1 of DM offered at 4 g kg-1 of BW for 28 days and protein-energy supplement with 180 g protein kg-1 of DM offered at 8 g kg-1 of BW for 28 days and protein-energy supplement with 180 g protein kg-1 of DM offered at 12 g kg-1 BW for 28 days. The greatest average daily gain (ADG) were observed in heifers that received protein-energy supplement, except for the treatment offered at the last evaluation cycle (SP3), which did not differ from the control treatment (SP1). The greatest ADG in the treatments SP2, SP4 and SP5 resulted in final body weight of 300 kg BW. The use of energy protein supplementation with 180g/kg of protein DM during the wet-dry seasons transition period (SP5) resulted in animals with better carcass characteristics; however, the meat quality had similar characteristics between treatments. The use of protein supplement in the first period, followed by energy protein supplementation at increasing levels (SP2), reduced the production cost without affecting the profitability. The use of supplement with180 g protein kg-1 of DM concentration resulted in animals with the greatest carcass quality attributes compared to other treatments. However, among the strategies evaluated, the use of protein supplement only in the first period, followed by energy protein supplementation, reduces the cost of production without affecting the productivity and profitability of the system.