The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degrad...The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P<0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P>0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P<0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P>0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.展开更多
The present experiment was conducted to investigate the effects of fiber and threonine(Thr)on growth performance,intestinal morphology and immune responses of broiler chickens.A total of 420 one-dayold mixed sex broil...The present experiment was conducted to investigate the effects of fiber and threonine(Thr)on growth performance,intestinal morphology and immune responses of broiler chickens.A total of 420 one-dayold mixed sex broiler chicks(Ross 308)were randomly divided into 6 experimental diets and 5 replicates of 14 chicks based on a factorial arrangement(2 × 3)from 1 to 42 d of age.Experimental factors included dietary supplemental fiber type(no supplemental fiber[NSF],30 g/kg sugar beet pulp[SBP]or 30 g/kg rice hull[RH])and Thr inclusion level(100% or 110% of Thr requirement recommended by breeder company[Ross 308]).Growth performance of broilers was assayed at different periods of the experiment.Intestinal morphometric features were measured at 21 d of age.Antibody titer against sheep red blood cells(SRBC),Newcastle and influenza disease viruses were measured on d 30 of trial.Dietary inclusion of SBP and RH significantly decreased feed intake and weight gain during the entire rearing period(P<0.05).Interaction of fiber and Thr had no beneficial effects on the performance of chickens across the entire rearing phase.Dietary supplementation of 110% Thr required level improved jejunal morphometric features(P<0.05),whereas its inclusion with fibrous materials failed to show the same effects.Dietary supplemental Thr together with SBP significantly increased antibody production against SRBC(P<0.05).In conclusion,although supplemental 30 g/kg fibrous materials impaired growth performance,inclusion of SBP along with 110% Thr level improved the humoral immunity in broiler chickens.展开更多
基金Lorestan University,Iran,for its financial support。
文摘The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P<0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P>0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P<0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P>0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.
文摘The present experiment was conducted to investigate the effects of fiber and threonine(Thr)on growth performance,intestinal morphology and immune responses of broiler chickens.A total of 420 one-dayold mixed sex broiler chicks(Ross 308)were randomly divided into 6 experimental diets and 5 replicates of 14 chicks based on a factorial arrangement(2 × 3)from 1 to 42 d of age.Experimental factors included dietary supplemental fiber type(no supplemental fiber[NSF],30 g/kg sugar beet pulp[SBP]or 30 g/kg rice hull[RH])and Thr inclusion level(100% or 110% of Thr requirement recommended by breeder company[Ross 308]).Growth performance of broilers was assayed at different periods of the experiment.Intestinal morphometric features were measured at 21 d of age.Antibody titer against sheep red blood cells(SRBC),Newcastle and influenza disease viruses were measured on d 30 of trial.Dietary inclusion of SBP and RH significantly decreased feed intake and weight gain during the entire rearing period(P<0.05).Interaction of fiber and Thr had no beneficial effects on the performance of chickens across the entire rearing phase.Dietary supplementation of 110% Thr required level improved jejunal morphometric features(P<0.05),whereas its inclusion with fibrous materials failed to show the same effects.Dietary supplemental Thr together with SBP significantly increased antibody production against SRBC(P<0.05).In conclusion,although supplemental 30 g/kg fibrous materials impaired growth performance,inclusion of SBP along with 110% Thr level improved the humoral immunity in broiler chickens.