Effects of sodium lasalocid and roughage/concentrate ratio on ruminal fermentation in dry cows

• Autor(a) principal: Rodrigues, Paulo Henrique Mazza
• Data de Publicação: 2000
• Outros Autores: Lucci, Carlos de Sousa, Castro, Ari Luiz de
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Brazilian Journal of Veterinary Research and Animal Science
• Texto Completo: https://www.revistas.usp.br/bjvras/article/view/5824
• topic: Ionóforos; Ácidos graxos voláteis; Amônia; Ruminantes; Ionophores; Volatile fatty acids; Ammonia; Ruminants

Sodium lasalocid and different roughage:concentrates ratios were studied in a 4 x 4 change over design, with four canulated heifers (500 kg body weight). Treatments were applied in a 2 x 2 factorial arrangement with 40% or 70% of roughage (Coast Cross hay) and zero or 200 mg of lasalocid/animal/day. Ruminal liquid collections were made at the twentieth first day of each experimental subperiod at 0, 1, 2, 3, 4, 6, and 8 hours after first meal. Statistical interaction between lasalocid and roughage:concentrate ratio was detected in molar percentage of propionate (p < 0.05): lower roughage diet increased propionate 19.0% with lasalocid but only 0.6% without. Also, lower roughage diet decreased acetate:propionate ratio 20.6% with and only 4.9% without lasalocid (p < 0.05). Acetate was 4.7% lower and butirate 15.7% greater at the 40% roughage diet, with or without lasalocid (p < 0.05). Lower roughage diets increased DM consumption (p < 0.05), decreased ruminal ammonia concentration since four hours after the first meal (p < 0.05), decreased ruminal pH since two hours after the first meal (p < 0.05) and decreased ruminal liquid turnover by quilogram of DM consummed (p < 0.05), but did not result in differences of liquid ruminal volume or blood urea concentrations.