We evaluatedthe effects of diets with different crude protein (CP) levels on growth performance, rumen fermentation and bacterial communities in weaned Chahaer lambs. 128 weaned Chahaer lambs ((20.56±1.43) k...We evaluatedthe effects of diets with different crude protein (CP) levels on growth performance, rumen fermentation and bacterial communities in weaned Chahaer lambs. 128 weaned Chahaer lambs ((20.56±1.43) kg body weight; ram:ewe 1:1) aged (61±1.85) d were randomly alotted to one of four diets with CP content of 11.17% (T1), 12.06% (T2), 13.40% (T3) or 14.36% (T4).Ruminal fermentation parameters were measured and bacterial communities were analysed using PCR-dena-turing gradient gel electrophoresis (PCR-DGGE) and quantitative PCR. The average daily gain and feed utilization efifciency in T3 were higher than those in the other groups (P〈0.05), although the dry matter intake and metabolizable energy intake were similar. Total volatile fatty acid concentration in the ruminal lfuid of T3 was lower than that of T1 (P=0.011), T2 (P=0.008) or T4 (P=0.309). The ammonia nitrogen concentration and acetate/propionate ratio of ruminal lfuid were signiifcantly higher in lambs fed the higher CP diets, whereas the molar concentrations of propionate and butyrate of ruminal lfuid were lower. The rumen bacterial community was similar in T2 and T3 which shown more stable and diverse rumen microbes ecosystem compared with the other groups. The DGGE proifles and phylogenetic tree indicated thatBacteroides uniformis,Clostrid-iumalkalicellulosi,Alkalibaculum bacchiandSaccharofermentanssp.were common bacterium of Chahaer lamb rumen. B. uniformis,C.alkalicelulosi,Saccharofermentanssp. andGracilibacter thermotolerans,which belong to the Bacteroidetes and Firmicutesphyla,were the dominant species in the rumen of lambs fed 13.40% CP.However,Ruminococcus albus, Ruminococcus lfavefaciensand Butyrivibrio ifbrisolvenswerenot differentin lambs fed different CP diets. Therefore, it could be concluded thatB. uniformis,C.alkalicelulosi,A. bacchiandSaccharofermentanssp.were common bacteria of Chahaer lamb rumen. Furthermore, the dietary CP of 13.04% could improve performance and change rume展开更多
基金a part of the Public Service Program(Agriculture)Special Fund for Agro-scientific Research in the Public Interest,China(201303062)
文摘We evaluatedthe effects of diets with different crude protein (CP) levels on growth performance, rumen fermentation and bacterial communities in weaned Chahaer lambs. 128 weaned Chahaer lambs ((20.56±1.43) kg body weight; ram:ewe 1:1) aged (61±1.85) d were randomly alotted to one of four diets with CP content of 11.17% (T1), 12.06% (T2), 13.40% (T3) or 14.36% (T4).Ruminal fermentation parameters were measured and bacterial communities were analysed using PCR-dena-turing gradient gel electrophoresis (PCR-DGGE) and quantitative PCR. The average daily gain and feed utilization efifciency in T3 were higher than those in the other groups (P〈0.05), although the dry matter intake and metabolizable energy intake were similar. Total volatile fatty acid concentration in the ruminal lfuid of T3 was lower than that of T1 (P=0.011), T2 (P=0.008) or T4 (P=0.309). The ammonia nitrogen concentration and acetate/propionate ratio of ruminal lfuid were signiifcantly higher in lambs fed the higher CP diets, whereas the molar concentrations of propionate and butyrate of ruminal lfuid were lower. The rumen bacterial community was similar in T2 and T3 which shown more stable and diverse rumen microbes ecosystem compared with the other groups. The DGGE proifles and phylogenetic tree indicated thatBacteroides uniformis,Clostrid-iumalkalicellulosi,Alkalibaculum bacchiandSaccharofermentanssp.were common bacterium of Chahaer lamb rumen. B. uniformis,C.alkalicelulosi,Saccharofermentanssp. andGracilibacter thermotolerans,which belong to the Bacteroidetes and Firmicutesphyla,were the dominant species in the rumen of lambs fed 13.40% CP.However,Ruminococcus albus, Ruminococcus lfavefaciensand Butyrivibrio ifbrisolvenswerenot differentin lambs fed different CP diets. Therefore, it could be concluded thatB. uniformis,C.alkalicelulosi,A. bacchiandSaccharofermentanssp.were common bacteria of Chahaer lamb rumen. Furthermore, the dietary CP of 13.04% could improve performance and change rume