Reduction of adaptation to high-energy diets using virginiamycin: protozoa and rumen degradability

• Autor(a) principal: Squizatti, M. M. [UNESP]
• Data de Publicação: 2019
• Outros Autores: Rigueiro, A. L. N. [UNESP], Soares, C. H. G. [UNESP], Nunes, A. B. C. P. [UNESP], Demartini, B. L. [UNESP], Felizari, L. D. [UNESP], Pinto, A. C. J. [UNESP], Millen, D. D. [UNESP], Chizzotti, M. L.
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.3920/978-90-8686-891-9_62; http://hdl.handle.net/11449/210692
• topic: concentrate; fermentation; metabolism

The objective of this study was to evaluate the reduction of adaptation time to high-energy diets for cannulated Nellore cattle using Virginiamycin (VM) as a feed additive, in which ciliated protozoa and rumen nutrient degradability were assessed. The experimental design was a 5x5 Latin square, where each period lasted 21 days, with 7-day washout between periods. Five 17 mo-old Nellore yearling bulls were used (415 +/- 22 kg of body weight), and the animals were divided into five treatments: (1) MON (30 mg/kg) and adaptation for 14 days; (2) MON (30 mg/kg) + VM (25 mg/kg) and adaptation for 14 days; (3) VM (25 mg/kg) and adaptation for 14 days; (4) VM (25 mg/kg) and adaptation for 9 days; and (5) VM (25 mg/kg) and adaptation for 6 days. As the adaptation length decreased for animals consuming only VM, the rumen degradability of DM (P<0.01), NDF (P<0.01) and starch (P<0.01) decreased; however, protozoa counts of Entodinium and Total protozoa increased. It is not recommended to adapt Nellore cattle in less than 14 days.