Abstract

VEDOVATTO, Marcelo et al. Inclusion of concentrate and growth promoters’ additives in sheep diets on intake, digestibility, degradability, ruminal variables and nitrogen balance. Rev. mex. de cienc. pecuarias [online]. 2020, vol.11, n.1, pp.132-152.  Epub June 11, 2020. ISSN 2448-6698.  https://doi.org/10.22319/rmcp.v11i1.4981.

This study evaluated the inclusion of concentrate and monensin, salinomycin and flavomycin in sheep diets on intake, digestibility, in situ degradability, ruminal variables and nitrogen balance. Five sheep in a latin square received the treatments: HAY (hay only), CONT (hay + concentrate), MON (hay + concentrate + monensin), SALI (hay + concentrate + salinomycin), and FLAV (hay + concentrate + flavomycin). Hay was offered ad libitum, concentrate, 20 g kg-1 of body weight (BW), and additives, 0.75 mg kg-1 of BW. The treatments with the concentrate (CONT, MON, SALI and FLAV) showed increased (P≤0.05) on intake, digestibility, total VFA, propionate and butyrate proportions, N-NH3, and nitrogen balance, and decreased (P≤0.05) DM and NDF degradability, acetate proportion, acetate:propionate ratio, and rumen pH compared to the HAY. The comparison between the outcome effects from additives with the CONT showed that the acetate proportion and acetate:propionate ratio was only reduced by MON (P≤0.05). MON and SALI increased (P≤0.05) the propionate proportion. The proportion of butyrate was increased with the inclusion of FLAV and reduced with MON 8and SALI. Only MON reduced the production of N-NH3 (P≤0.05). Other variables showed no effects from additives (P>0.05) in relation to the CONT. The inclusion of the concentrate in sheep diets caused alterations on intake, digestibility, ruminal variables (VFA, pH, and N-NH3) and nitrogen balance. However, the additives only altered the ruminal variables (VFA and N-NH3) and the greatest effects were observed with MON.

Keywords : Bambermycin; Flavomycin; Monensin; Ruminants; Salinomycin.