Replacing urea with ammonium chloride in cattle diets: digestibility, synthesis of microbial protein, and rumen and plasma parameters/Substituicao de ureia por cloreto de amonio em dietas de bovinos: digestibilidade, sintese de proteina microbiana, parametros ruminais e sanguineos

• Published in: Acta scientiarum. Animal sciences Vol. 31; no. 3; p. 271
• Main Authors: Castaneda, Roman David, Branco, Antonio Ferriani, Coneglian, Sabrina Marcantonio, Barreto, Julio Cesar, Granzotto, Fernanda, Teixeira, Silvana
• Format: Journal Article
• Language: Spanish
• Published: Universidade Estadual de Maringa 01.07.2009
• ISSN: 1806-2636
• DOI: 10.4025/actascianimsci.v31i3.5938

Replacing urea with ammonium chloride in cattle diets: digestibility, synthesis of microbial protein, and rumen and plasma parameters. Five Holstein steers weighting 450 kg were used in a 5 x 5 Latin square statistical design, where treatments consisted of five replacement levels: 0, 25, 50, 75 and 100% of urea by ammonium chloride, as non-protein nitrogen in the diet. There was a linear decrease (p < 0.05) on intake and fecal flow, as well as a linear increase in apparent digestibility of DM, OM, CP, NDF and EE as result of ammonium chloride inclusion in the diet. There was a quadratic effect (p < 0.05) on urine pH and a linear increase of urine volume and uric acid (p < 0.05) as a result of ammonium chloride use. Treatments did not influence (p > 0.05) daily excretion of allantoin, purine derivatives, absorbed purines, as well as microbial nitrogen compounds and microbial efficiency synthesis. Rumen pH and plasma urea nitrogen decreased linearly (p < 0.05) but treatments did not influence (p > 0.05) ruminal ammonia concentration as urea was replaced by ammonium chloride. Ammonium chloride can be used as a nonprotein nitrogen source in ruminant diets up to level of 1.4% of diet dry matter. Key words: purine derivatives, ruminal fermentation, intake, non-protein nitrogen, ruminants, anionic salts. Foram utilizados cinco bovinos machos, castrados, da raca Holandesa Preta e Branca, com 450 kg de peso vivo em um delineamento quadrado latino 5 x 5, sendo os tratamentos cinco niveis de substituicao, 0, 25, 50, 75 e 100% de ureia por cloreto de amonio, como fontes de nitrogenio nao-proteico da dieta. Houve reducao linear (p < 0,05) na ingestao e no fluxo fecal, alem de aumento na digestibilidade da MS, MO, PB, FDN e EE com a inclusao do cloreto de amonio na dieta. A inclusao de cloreto de amonio na dieta influenciou de forma quadratica (p < 0,05) o pH da urina, aumentou (p < 0,05) o volume urinario assim como a excrecao de acido urico. Os tratamentos nao influenciaram (p > 0,05) a excrecao de alantoina e de derivados de purinas na urina, purinas absorvidas, sintese de compostos nitrogenados microbianos e eficiencia de sintese de proteina microbiana. Houve queda linear (p < 0,05) no pH do liquido ruminal e N ureico plasmatico com a substituicao da ureia pelo cloreto de amonio, mas os tratamentos nao influenciaram (p > 0,05) a concentracao de amonia no rumen. O cloreto de amonio pode ser utilizado como fonte de NNP para bovinos em niveis de ate 1,4% da materia seca total da dieta. Palavras-chave: derivativos de purina, fermentacao ruminal, ingestao, nitrogenio nao-proteico, ruminantes, sais anionicos.