Utilização de Bovaer® (3-nitrooxipropanol) em dietas para bovinos confinados

Abstract

The objective of this work was to evaluate the effects of 3-nitrooxypropanol (3-NOP, Bovaer, DSM Nutritional Products) at different levels in diets for confined beef cattle on productive performance, biological efficiency and methane (CH4) emissions. Thirty Nellore bulls with an average weight of 407 ± 6 kg were randomly distributed into three treatments with ten replicates (animal) per treatment. The animals were fed a high concentrate diet for 86 days, according to the three treatments: 1) 0, Control (without addition of 3-NOP); 2) BV75 (75 mg/kg DM of 3-NOP), 3) BV100 (100 mg/kg DM of 3-NOP). Gas emissions (CH4 and H2) were evaluated individually using the GreenFeed unit (C-Lock, USA), while dry matter consumption variables (DMI) were evaluated using digital feeders (Sistema Intergado, Brazil). The animals' body weights were recorded after a 12-hour fast at the beginning and end of the experiment. The data were subjected to PROC MIXED analysis of SAS 9.4, evaluated by orthogonal contrasts, with a significance level of 5%. The initial PV was used as a covariate when significant for adjusting the statistical model. No differences were observed in DMI (kg/d and %LW) between control animals and those fed with 3-NOP. Animals fed with BV75 had higher ADG than control and BV100, (1.73 vs. 1.63 and 1.60 kg/d, respectively) and better biological efficiency than control (127.0 vs. 135.3 kg IMS/BV of carcass produced. A similar result was observed for carcass gain, in which animals supplemented with BV75 had greater gains than the control. Animals fed with 75 and 100 mg/kg of 3-NOP MS emitted respectively 33.7% and 42.7% less methane (g/d) compared to control, and additionally produced more hydrogen vs. control There were significant reductions in methane production measured in relation to DMI (CH4: DMI) and methane intensity (CH4/GMD) for animals fed both levels of 3-NOP , compared to the control, as well as a significant difference in CH4 reduction in relation to biological efficiency for animals fed with 3-NOP. Differences were observed in pH, WHC, FC and fat content of the meat in the groups with 3-NOP inclusion compared to the control, 3-NOP was also significant for the lipid composition, presenting higher concentration of meat fatty acids for C14:1, C16:1, C17:1, C18:2 CLA, C18:3 ⱷ3 and C20:1. We concluded that feeding 3-NOP consistently reduces methane emissions from confined cattle, in which the intensity of the reduction increased over the dosages evaluated in the present study, without harming animal performance and meat quality.