Association of additives in cattle supplement finished pasture at the rainy season

Author(s)

Erick Escobar Dallantonia

• Document type: Master's Dissertation
• Press: Jaboticabal. 2017-04-26.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal
• Defense date: 2017-02-23
• Advisor: Telma Teresinha Berchielli; Josiane Fonseca Lage

Abstract

Two experiments were conducted in order to evaluate the effect of the use of additives in supplementation of steers finished at pasture during the rainy season, on intake, digestibility, ruminal fermentation, microorganism profile in the rumen, performance, methane emissions, meat quality and carcass characteristics. For the evaluate the ruminal parameters, 12 cannulated Nellore in the rumen were used, with an average weight of 518.42 ± 55.40 kg and for the performance of young bulls were used 90 Nellore with average initial weight of 360 kg ± 24.98 kg and submitted to protein-energy supplementation in 0.3% body weight. The treatments were four supplements with different additives, and additives without supplement (SUPL), supplementation with monensin (MN), supplementation with virginiamycin (VM) and supplement with monensin association and virginiamycin (MNVM). The DM intake tended to decrease (P = 0.07) for animals supplemented with additives and the ruminal pH was higher of this animals (P <0.05). The proportion of butyrate was affected (P <0.05), the acetate ratio tended to decrease in VM fed animals compared to MN fed animals (P = 0.07), however, the propionate and the A / P ratio was not affected by the inclusion of the additives (P> 0.05). The use of additives increased the proportion of gram-positive bacteria and decreased of the gram-negative bacteria (P <0.05), in addition, no adaptive effect of the microorganisms was observed during the experimental period. The hot carcass weight and carcass gain (P> 0.05) was not affected by treatments with additives, however, carcass yield, ADG and feed efficiency (P <0.05) were affected, the animals receiving MNVM consumed less and maintained ADG equal to SUPL, resulting in better feed efficiency. There was a tendency to reduce the emission of methane (g / kg of carcass gain) in animals fed MNVM (P = 0.07). The use of additives allowed an effective control of gramnegative bacteria, but no decrease in methane production was observed. Already the association improved the feed efficiency of the animals and had no effect on the ADG. (AU)

• FAPESP's process: 15/05216-7 - Additives in suplementation of Nellore young bulls finished in pasture at the rainy season
• Grantee: Erick Escobar Dallantonia
• Support Opportunities: Scholarships in Brazil - Master