Aerobes and anaerobe facultative Gram-negative rod-shaped bacteria in the ruminal fluid of beef cattle fed lignified pasture and steers with ruminal acidosis

作者：Vieira Edvaldo Alves; Abrao Flavia O; Ribeiro Izabella Carolina O; Nigri Carolina de A; da Silva Kariny F; Careli Roberta T; Geraseev Luciana C; Duarte Eduardo R^*

来源：Pesquisa Veterinaria Brasileira, 2015, 35(9): 811-816.

DOI：10.1590/S0100-736X2015000900007

• Cattle
• Enterobacteriaceae
• ruminal microbiota
• rumen acidosis
• semiarid

This study aimed to analyze the population of Gram negative bacteria, rod-shaped aerobic and facultative anaerobes, in ruminal fluid of health Zebu cattle of different categories fed in tropical pasture and steers fed high levels of grain and without bulky. Rumen fluid from 32 cows, 50 steers and 50 calves fed on Brachiaria spp. and 20 steers with ruminal acidosis were collected. After decimal dilutions, the samples were inoculated on petri dishes with agar MacConkey at 39 degrees C. Biochemical tests were used to identify the most common genera these bacteria. The concentration of these bacteria did not differ in the rumen of cows, calves and calves fed lignified tropical pasture and the most frequently identified genera for these animals were Escherichia, Enterobacter and Klebsiella. However, steers fed without forage and with acidosis showed a higher detection rate and larger population of these bacteria in the rumen (> 6 log/ml) compared to steers fed only pasture. The Escherichia coli species was predominant among theses bacteria isolated from the rumen fluid of steers with acidosis ( p< 0.01). In beef zebu cattle raised on pasture lignified, the population of these microorganisms in the rumen is low showing greater diversity of genera. However in confined zebu steers fed without forage and with sub acute ruminal acidosis occur disequilibrium with increased E. coli population.

• 出版日期2015-9