The feeding amount of bamboo rats in Southern China is increased year by year. Under condition of captive breeding, the occurrence of diseases has also become more and more frequent in bamboo rats. In this paper, the ...The feeding amount of bamboo rats in Southern China is increased year by year. Under condition of captive breeding, the occurrence of diseases has also become more and more frequent in bamboo rats. In this paper, the results of mor- phological and biochemical studies showed that the cultural and biochemical charac- teristics of isolated strains are basically the same, and they all have strong pathogenicities to bamboo rats. The disease was diagnosed to be caused by the mixed infection of Escherichia coil and Arthrinium saccharico/a, and it was controlled by corresponding measures.展开更多
AIM:To study the effects of live and dead Lactobacillus rhamnosus GG(GG) on rotavirus infection in a neonatal rat model.METHODS:At the age of 2 d,suckling Lewis rat pups were supplemented with either live or dead GG a...AIM:To study the effects of live and dead Lactobacillus rhamnosus GG(GG) on rotavirus infection in a neonatal rat model.METHODS:At the age of 2 d,suckling Lewis rat pups were supplemented with either live or dead GG and the treatment was continued daily throughout the experi-ment.At the age of 5 and 6 d the pups received oral rotavirus(RV) SA-11 strain.The pups were sacrificed at the age of 7 or 8 d by decapitation.The gastrointestinal tract was removed and macroscopic observations were done.The consistency of feces in the colon was classified using a four-tier system.RV was detected from the plasma,small intestine,colon and feces by real-time quantitative polymerase chain reaction(PCR).RESULTS:In this neonatal rat model,RV induced a mild-to-moderate diarrhea in all except one pup of the RV-inoculated rats.RV moderately reduced body weight development from day 6 onwards.On day 7,after 2 d of RV infection,live and dead GG groups gained significantly more weight than the RV group without probiotics [36%(P = 0.001) and 28%(P = 0.031),respectively].In addition,when compared with the RV control group,both live and dead GG reduced the weight ratio of colon/animal body weight to the same level as in the healthy control group,with reductions of 22%(P = 0.002) and 28%(P < 0.001),respectively.Diarrhea increased moderately in both GG groups.However,the diarrhea incidence and severity in the GG groups were not statistically significantly different as compared with the RV control group.Moreover,observed diarrhea did not provoke weight loss or death.The RV control group had the largest amount of RV PCR-positive samples among the RV-infected groups,and the live GG group had the smallest amount.Rats receiving live GG had significantly less RV in the colon(P = 0.027) when compared with the RV control group.Live GG was also more effective over dead GG in reducing the quantity of RV from plasma(P = 0.047).CONCLUSION:Both live and dead GG have beneficial effects in RV infection.GG may increase RV clearance from the body and reduce colon swelling.展开更多
In recent years, research on biopolymer based-coating containing natural antimicrobial agents is developing significantly. The objective of this study was to evaluate the antimicrobial efficiency of six formulations c...In recent years, research on biopolymer based-coating containing natural antimicrobial agents is developing significantly. The objective of this study was to evaluate the antimicrobial efficiency of six formulations containing pre-selected natural antimicrobial compounds against Listeria monocytogenes, Escherichia coli O 157：H7, Salmonella typhimurium, the total bacteria and total yeasts and molds in cauliflower. Each formulation was subjected to a sensory test in parallel to microbiological analysis and the efficiency during storage at 5 ℃ was evaluated for the two best formulations, based on their ability to eliminate the target microorganisms. Both formulations were able to reduce all pathogens and total flora below detectable levels after 24 h of storage at 5 ℃. Using washing or spraying treatments, the two formulations were able to reduce Listeria to undetectable levels for 3 d. This efficiency was extended to 7 d when the formulations were incorporated into an edible coating. Washing treatment with the two formulations was also able to limit the growth of yeast and molds at levels lower than 2 log, for more than 7 d. The population of E. coli was reduced to below the detection limit during 14 d of storage, after washing treatment with the two formulations. The spraying treatment of cauliflower with the formulations allowed the use of very small amounts of antimicrobials while maintaining a fairly good efficiency, greatly reducing the potential costs of implementing this method in the industry. Future research may focus on development of nanoemulsion of antimicrobial formulations based on the developed antimicrobial formulations in this study to improve the better coating efficiency.展开更多
文摘The feeding amount of bamboo rats in Southern China is increased year by year. Under condition of captive breeding, the occurrence of diseases has also become more and more frequent in bamboo rats. In this paper, the results of mor- phological and biochemical studies showed that the cultural and biochemical charac- teristics of isolated strains are basically the same, and they all have strong pathogenicities to bamboo rats. The disease was diagnosed to be caused by the mixed infection of Escherichia coil and Arthrinium saccharico/a, and it was controlled by corresponding measures.
基金Supported by Valio Ltd and the Finnish Funding Agency of Technology and InnovationThe Foundation for Nutrition Research has financially contributed to Liisa Lehtoranta’s doctoral studies
文摘AIM:To study the effects of live and dead Lactobacillus rhamnosus GG(GG) on rotavirus infection in a neonatal rat model.METHODS:At the age of 2 d,suckling Lewis rat pups were supplemented with either live or dead GG and the treatment was continued daily throughout the experi-ment.At the age of 5 and 6 d the pups received oral rotavirus(RV) SA-11 strain.The pups were sacrificed at the age of 7 or 8 d by decapitation.The gastrointestinal tract was removed and macroscopic observations were done.The consistency of feces in the colon was classified using a four-tier system.RV was detected from the plasma,small intestine,colon and feces by real-time quantitative polymerase chain reaction(PCR).RESULTS:In this neonatal rat model,RV induced a mild-to-moderate diarrhea in all except one pup of the RV-inoculated rats.RV moderately reduced body weight development from day 6 onwards.On day 7,after 2 d of RV infection,live and dead GG groups gained significantly more weight than the RV group without probiotics [36%(P = 0.001) and 28%(P = 0.031),respectively].In addition,when compared with the RV control group,both live and dead GG reduced the weight ratio of colon/animal body weight to the same level as in the healthy control group,with reductions of 22%(P = 0.002) and 28%(P < 0.001),respectively.Diarrhea increased moderately in both GG groups.However,the diarrhea incidence and severity in the GG groups were not statistically significantly different as compared with the RV control group.Moreover,observed diarrhea did not provoke weight loss or death.The RV control group had the largest amount of RV PCR-positive samples among the RV-infected groups,and the live GG group had the smallest amount.Rats receiving live GG had significantly less RV in the colon(P = 0.027) when compared with the RV control group.Live GG was also more effective over dead GG in reducing the quantity of RV from plasma(P = 0.047).CONCLUSION:Both live and dead GG have beneficial effects in RV infection.GG may increase RV clearance from the body and reduce colon swelling.
文摘In recent years, research on biopolymer based-coating containing natural antimicrobial agents is developing significantly. The objective of this study was to evaluate the antimicrobial efficiency of six formulations containing pre-selected natural antimicrobial compounds against Listeria monocytogenes, Escherichia coli O 157：H7, Salmonella typhimurium, the total bacteria and total yeasts and molds in cauliflower. Each formulation was subjected to a sensory test in parallel to microbiological analysis and the efficiency during storage at 5 ℃ was evaluated for the two best formulations, based on their ability to eliminate the target microorganisms. Both formulations were able to reduce all pathogens and total flora below detectable levels after 24 h of storage at 5 ℃. Using washing or spraying treatments, the two formulations were able to reduce Listeria to undetectable levels for 3 d. This efficiency was extended to 7 d when the formulations were incorporated into an edible coating. Washing treatment with the two formulations was also able to limit the growth of yeast and molds at levels lower than 2 log, for more than 7 d. The population of E. coli was reduced to below the detection limit during 14 d of storage, after washing treatment with the two formulations. The spraying treatment of cauliflower with the formulations allowed the use of very small amounts of antimicrobials while maintaining a fairly good efficiency, greatly reducing the potential costs of implementing this method in the industry. Future research may focus on development of nanoemulsion of antimicrobial formulations based on the developed antimicrobial formulations in this study to improve the better coating efficiency.
