Background： Colibacillosis caused by enterotoxigenic Escherichia coil （E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varyin...Background： Colibacillosis caused by enterotoxigenic Escherichia coil （E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum （C. butyficum） on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli （E. coil） K88. Methods： The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment （NC） consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment （PC） consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment （CB） consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment （CS） consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results： The body weight （BW） and average day gain （ADG） in the broilers of CB group were higher （P 〈 0.05） than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher （P 〈 0.05） concentration of tumor necrosis factor-a （TNF-a） at 3 and 7 d post-challenge, and higher （P 〈 0.05） concentration of interleukin-4 （IL-4） at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower （P 〈 0.05） at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower （P 〈 0.05） at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher （P 〈 0.05） jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower （P 〈 0.05） jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher （P 〈 0.05） activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher （P 〈 0.05） activity of lipase at 3, 7 d post-challenge than PC birds.展开更多
[Objective] On the basis of previous researches, this experiment aimed to analyze the effect of K＊ and the interaction of K＋ , salinity （ s）, Ca2＋ , Mg2＋ on growth and adenosine triphosphatase （ATPase）, which ...[Objective] On the basis of previous researches, this experiment aimed to analyze the effect of K＊ and the interaction of K＋ , salinity （ s）, Ca2＋ , Mg2＋ on growth and adenosine triphosphatase （ATPase）, which was closely related to growth, of Litopenaeus vannamei. [Method] 5 -week Litopenaeus vannamei breeding experiment was performed according to L16（215） orthogonal experiment design. Then the effect of K＋ and the interaction of K＋ , salinity, Ca2＋ , Mg2＋ in water on survival, growth and ATP enzyme activity of Litopenaeus vannamei. [Result] K＋ had signifi- cant effect on survival rate, length and weight gain, ATP enzyme activity in Litopenaeus vannarnei. The highest survival rate was at K＂ of 150 rng/L. The fastest growth rate was at 50 mg/L, as well as the activities of Na＊ - K＋ -ATPase, Mg2＋ -ATPase, Ca＋ -ATPase. The interaction of salini- ty, Ca2＋ , Mg2＋ , K ＋ in water also had significant effect on survival rate, length and weight gain, ATP enzyme activity in Litopenaeus vannamei. [Conclusion] Among the horizontal combinations of factors in the experiment, the optimal combination for Litopenaeus vannamei survival rate was salinity of 15, K＋ of 150 mg/L, Ca2＋ of 100 mg/L, Mg2＋ of 300 mg/L, the optimal combination for growth rate was salinity of 15, K＋ of 50 mg/L, Ca2＋ 100 mg/L, Mg2＋ 100 mg/L, the optimal combination for Na＋ -K＊ -ATPase, Mg2＋ -ATPase, Ca2＋ -ATPase activity in Litopenaeus van- namei was salinity of 5, K＋ of 50 mg/L, Ca2＋ of 100 mg/L, Mg2＋ of 100 mg/L.展开更多
The gene of enzyme（Ape1547） was cloned from hyperthermophilic archaeon Aeropyrum pernix K1 and expressed in Escherichia coil.The effect of calcium cation on the properties of Ape1547 was studied.Ape1547 exhibits bot...The gene of enzyme（Ape1547） was cloned from hyperthermophilic archaeon Aeropyrum pernix K1 and expressed in Escherichia coil.The effect of calcium cation on the properties of Ape1547 was studied.Ape1547 exhibits both peptidase activity and esterase activity.The fluorescence spectrum shows that calcium cation quenches the fluorescence of the enzyme through static quenching mechanism,indicating that calcium cation was bound to the enzyme.Based on the study of calcium cation on CD ellipticity of Ape1547 by circular dichroism,we concluded that the change of enzyme structure induced by calcium cation may be responsible for the change of enzyme activity.Calcium cation has dual effects on Ape1547：it could activate the enzyme activity when its concentration was 0.1 mol/L,and the enzyme had the highest activity;however,when its concentration was higher than 0.2 mol/L,the enzyme activity was inhibited.The results indicate that the activity center of peptidase activity might involve more amino acid residues than that of esterase activity.展开更多
基金supported by the International Cooperation Project of Zhejiang Province(No.2012C14031)Innovative Research Team Program of Zhejiang Province(No.2011R50025)
文摘Background： Colibacillosis caused by enterotoxigenic Escherichia coil （E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum （C. butyficum） on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli （E. coil） K88. Methods： The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment （NC） consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment （PC） consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment （CB） consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment （CS） consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results： The body weight （BW） and average day gain （ADG） in the broilers of CB group were higher （P 〈 0.05） than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher （P 〈 0.05） concentration of tumor necrosis factor-a （TNF-a） at 3 and 7 d post-challenge, and higher （P 〈 0.05） concentration of interleukin-4 （IL-4） at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower （P 〈 0.05） at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower （P 〈 0.05） at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher （P 〈 0.05） jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower （P 〈 0.05） jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher （P 〈 0.05） activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher （P 〈 0.05） activity of lipase at 3, 7 d post-challenge than PC birds.
基金Key Projects of Science and Technology Promoting Farm in Shanghai City (Shanghai Agricultural Key Project [2010] No.1-6 )Science and Technology Promoting Projects of Science and Technology Promoting Farm in Shanghai City(Shanghai Agricultural Promoting Project [2008]No.5 -1 )Leading Academic Discipline Project of Shanghai Education Commission(J50701)
文摘[Objective] On the basis of previous researches, this experiment aimed to analyze the effect of K＊ and the interaction of K＋ , salinity （ s）, Ca2＋ , Mg2＋ on growth and adenosine triphosphatase （ATPase）, which was closely related to growth, of Litopenaeus vannamei. [Method] 5 -week Litopenaeus vannamei breeding experiment was performed according to L16（215） orthogonal experiment design. Then the effect of K＋ and the interaction of K＋ , salinity, Ca2＋ , Mg2＋ in water on survival, growth and ATP enzyme activity of Litopenaeus vannamei. [Result] K＋ had signifi- cant effect on survival rate, length and weight gain, ATP enzyme activity in Litopenaeus vannarnei. The highest survival rate was at K＂ of 150 rng/L. The fastest growth rate was at 50 mg/L, as well as the activities of Na＊ - K＋ -ATPase, Mg2＋ -ATPase, Ca＋ -ATPase. The interaction of salini- ty, Ca2＋ , Mg2＋ , K ＋ in water also had significant effect on survival rate, length and weight gain, ATP enzyme activity in Litopenaeus vannamei. [Conclusion] Among the horizontal combinations of factors in the experiment, the optimal combination for Litopenaeus vannamei survival rate was salinity of 15, K＋ of 150 mg/L, Ca2＋ of 100 mg/L, Mg2＋ of 300 mg/L, the optimal combination for growth rate was salinity of 15, K＋ of 50 mg/L, Ca2＋ 100 mg/L, Mg2＋ 100 mg/L, the optimal combination for Na＋ -K＊ -ATPase, Mg2＋ -ATPase, Ca2＋ -ATPase activity in Litopenaeus van- namei was salinity of 5, K＋ of 50 mg/L, Ca2＋ of 100 mg/L, Mg2＋ of 100 mg/L.
基金Supported by the National Natural Science Foundation of China(Nos.30400081 and 20772046)
文摘The gene of enzyme（Ape1547） was cloned from hyperthermophilic archaeon Aeropyrum pernix K1 and expressed in Escherichia coil.The effect of calcium cation on the properties of Ape1547 was studied.Ape1547 exhibits both peptidase activity and esterase activity.The fluorescence spectrum shows that calcium cation quenches the fluorescence of the enzyme through static quenching mechanism,indicating that calcium cation was bound to the enzyme.Based on the study of calcium cation on CD ellipticity of Ape1547 by circular dichroism,we concluded that the change of enzyme structure induced by calcium cation may be responsible for the change of enzyme activity.Calcium cation has dual effects on Ape1547：it could activate the enzyme activity when its concentration was 0.1 mol/L,and the enzyme had the highest activity;however,when its concentration was higher than 0.2 mol/L,the enzyme activity was inhibited.The results indicate that the activity center of peptidase activity might involve more amino acid residues than that of esterase activity.
