R. Bras. Zootec.24/Jul/2019;48:e20190114.

Effects of antibiotic growth promoters mixed with mineral supplement on growth performance, ingestive behavior, and mineral intake of grazing bulls

Marcelo Vedovatto ORCID logo , José Mauro da Silva Diogo ORCID logo , João Artêmio Marin Beltrame ORCID logo , Marcella Cândia D'Oliveira ORCID logo , Cássio José da Silva ORCID logo , Clayton Quirino Mendes ORCID logo , Sergio Lucio Salomon Cabral Filho ORCID logo , Gumercindo Loriano Franco ORCID logo

DOI: 10.1590/rbz4820190114

ABSTRACT

The objective was to evaluate the addition of antibiotic growth promoters to free-choice mineral supplement on ingestive behavior, mineral intake, and growth performance of grazing bulls. Sixty Nellore bulls [initial body weight (BW) of 219±17.8 kg and 15±2 months of age] were divided in 12 marandu grass paddocks. The treatments were: mineral supplement (control), mineral supplement + virginiamycin (VIRG), mineral supplement + lasalocid sodium (LASA) and mineral supplement + salinomycin sodium (SALI). Mineral supplements were formulated with target intake of 60 g d−1 and the growth promoters of 75 mg 100 kg−1 of BW. The experimental design was the completely randomized blocks. There was no treatment effect on ingestive behavior or mineral intake; however, the active ingredient intake differed between treatments. In the last experimental period, the intake of active ingredient LASA and SALI were higher than VIRG (0.66, 0.54, and 0.39 mg kg−1 of BW, respectively). Treatments also did not affect BW and average daily gain, which were 0.63, 0.60, 0.64, and 0.62 kg d−1 for control, VIRG, LASA, and SALI, respectively. Free-choice mineral supplementation intake by bulls has a high variability, and this impairs the regulation of the intake of antibiotic growth promoter additives. Therefore, the addition of antibiotic growth promoters to the mineral supplement does not affect ingestive behavior, mineral intake, and growth performance of grazing bulls.

Effects of antibiotic growth promoters mixed with mineral supplement on growth performance, ingestive behavior, and mineral intake of grazing bulls

Comments