Intake, nitrogen balance and microbial protein synthesis of steers fed with or without lipid addition

• Autor(a) principal: Bendia, Laila Cecília Ramos
• Data de Publicação: 2020
• Outros Autores: Fontes, Carlos Augusto de Alencar, Processi, Elizabeth Fonsêca, Silveira Filho, Clóvis Carlos, Lombardi, Cláudio Teixeira, Pimentel, Paulo Roberto Silveira, Oliveira, Ronaldo Lopes, Bezerra, Leilson Rocha, Rocha, Tiago Cunha
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Bioscience journal (Online)
• Texto Completo: https://seer.ufu.br/index.php/biosciencejournal/article/view/42294
• topic: Corn silage; Nitrogen balance; Ruminal ammonia; Soybeans; Soybean oil; Agricultural Sciences; Amônia ruminal; Balanço de nitrogênio; Óleo de soja; Silagem de milho; Soja

This study investigated the influence of energy supplementation with or without the addition of lipids on microbial production, microbial synthesis efficiency and nitrogen balance. Eight fistulated steers were used with accessible rumens and kept in individual stalls. Their diets consisted of corn silage; corn silage + concentrate; corn silage + concentrate with addition of lipids in the form of soybean oil; and corn silage + concentrate with addition of lipids in the form of soybean grains. Estimates of microbial protein synthesis were obtained based on the urinary excretion of purine derivatives. The concentrations of ammonia in the rumen were determined immediately at 2, 4, 6 and 8 hours after feeding. The diets with concentrate increased (P<0.05) the microbial protein synthesis and the efficiency of the synthesis and nitrogen balance without a difference between the lipid sources (P>0.05). Concentrated diets presented higher concentrations of urea nitrogen in the serum and urinary urea excretion (P<0.05), but there was no difference between the lipid sources (P>0.05). Energy supplementation, with or without lipid addition, can be used as a strategy to increase the synthesis of the microbial protein in the cattle fed corn silage.