A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog (Rana catesbeiana) cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella sp...A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog (Rana catesbeiana) cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. (46 isolates) followed by Aeromonas spp. (33 isolates), Flavobacterium spp. (31 isolates), and Vibrio spp. (30 isolates). Majority of the bacterial isolates were found sensitive to furazolidone (85.0%), chloramphenicol (85.0%), oxolinic acid (90.0%), florfenicol (95.0%), and flumequine (97.5%). On the other hand, most of the bacterial isolates were resistant to oleandomycin (77.5%) and lincomycin (87.5%). Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance (MAR) index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.展开更多
Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups.Each bullfrog in bacterium-injected group was injected intraperitoneally(i.p.) w...Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups.Each bullfrog in bacterium-injected group was injected intraperitoneally(i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml,while each one in control group injected i.p.with 0.2 ml sterile saline solution(0.85%,w/v).Three bullfrogs in both groups were sampled at 0,1,3,7,11,15 and 20 days post-injection(dpi) for the evaluation of non-specific immune parameters.It was observed that intraperitoneal injection of A.hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood.Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group.However,a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes.No significant difference in changes in the number of peripheral erythrocytes,serum superoxide dismutase(SOD) activity,and lysozyme activity was detected between the two groups.It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A.hydrophila infection.展开更多
Bullfrogs(Rana catesbeiana)are listed as one of the 100 worst invasive alien species in the world.They are generalist predators and thus may affect native species through predation.In previous studies,the food content...Bullfrogs(Rana catesbeiana)are listed as one of the 100 worst invasive alien species in the world.They are generalist predators and thus may affect native species through predation.In previous studies,the food contents of bullfrogs were mostly examined at a single site.In the present study,the diet composition of post-metamorphic bullfrogs on eight islands(Daishan,Liuheng,Xiushan,Fodu,Taohua,Xiashi,Cezi,and Putuoshan)in the Zhoushan Archipelago,Zhejiang Province of China,were examined by using the stomach flushing method from June 30 to August 11 in 2005.A total of 391 individual frogs were measured,including 113 adults and 278 juveniles.The analysis of the stomach contents shows that,for adult bullfrogs,the most important prey(by diet volume)overall were Decapoda,Coleoptera,Odonata,Mesogastropoda,Raniformes,and Cypriniformes.For juvenile bullfrogs,these were Decapoda,Coleoptera,Cypriniformes,Odonata,Orthoptera,Hymenoptera,Lepidoptera larvae,Mesogastropoda,and Raniformes.Moreover,the prey size and diet volume increased with the body size of both adult and juvenile bullfrogs.The diet composition of primary preys of bullfrogs was significantly different among the islands.The results indicate that bullfrogs exert different predatory influences on native fauna at different sites and that bullfrogs are generalist predators with extensive ecological impacts on native fauna.展开更多
牛蛙的生态养殖受到了养殖者的关注与重视。文章结合安徽省宿松县的实际情况,介绍了牛蛙(Rana catesbeiana)的生态养殖技术,包括牛蛙养殖场址的选择、养殖池的建造、养殖模式,以及常见的红腿病(Red-leg disease of frog)的防治措施,可...牛蛙的生态养殖受到了养殖者的关注与重视。文章结合安徽省宿松县的实际情况,介绍了牛蛙(Rana catesbeiana)的生态养殖技术,包括牛蛙养殖场址的选择、养殖池的建造、养殖模式,以及常见的红腿病(Red-leg disease of frog)的防治措施,可供养殖者参考。展开更多
基金funded by Universiti Malaysia Terengganu, Malaysia
文摘A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog (Rana catesbeiana) cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. (46 isolates) followed by Aeromonas spp. (33 isolates), Flavobacterium spp. (31 isolates), and Vibrio spp. (30 isolates). Majority of the bacterial isolates were found sensitive to furazolidone (85.0%), chloramphenicol (85.0%), oxolinic acid (90.0%), florfenicol (95.0%), and flumequine (97.5%). On the other hand, most of the bacterial isolates were resistant to oleandomycin (77.5%) and lincomycin (87.5%). Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance (MAR) index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.
基金Supported by National High-Tech Research and Development Program of China (863 Program, No.2001AA5070, 2002AA639600)Natural Science Foundation of Fujian Province of China (No.B0410022, 2006F5066)
文摘Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups.Each bullfrog in bacterium-injected group was injected intraperitoneally(i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml,while each one in control group injected i.p.with 0.2 ml sterile saline solution(0.85%,w/v).Three bullfrogs in both groups were sampled at 0,1,3,7,11,15 and 20 days post-injection(dpi) for the evaluation of non-specific immune parameters.It was observed that intraperitoneal injection of A.hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood.Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group.However,a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes.No significant difference in changes in the number of peripheral erythrocytes,serum superoxide dismutase(SOD) activity,and lysozyme activity was detected between the two groups.It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A.hydrophila infection.
基金supported by the National Natural Science Foundation of China (Grant No.30270246)the Knowledge Innovation Program of Chinese Academy of Sciences (No.KSCX3-IOZ-02 and KSCX2-SW-118).
文摘Bullfrogs(Rana catesbeiana)are listed as one of the 100 worst invasive alien species in the world.They are generalist predators and thus may affect native species through predation.In previous studies,the food contents of bullfrogs were mostly examined at a single site.In the present study,the diet composition of post-metamorphic bullfrogs on eight islands(Daishan,Liuheng,Xiushan,Fodu,Taohua,Xiashi,Cezi,and Putuoshan)in the Zhoushan Archipelago,Zhejiang Province of China,were examined by using the stomach flushing method from June 30 to August 11 in 2005.A total of 391 individual frogs were measured,including 113 adults and 278 juveniles.The analysis of the stomach contents shows that,for adult bullfrogs,the most important prey(by diet volume)overall were Decapoda,Coleoptera,Odonata,Mesogastropoda,Raniformes,and Cypriniformes.For juvenile bullfrogs,these were Decapoda,Coleoptera,Cypriniformes,Odonata,Orthoptera,Hymenoptera,Lepidoptera larvae,Mesogastropoda,and Raniformes.Moreover,the prey size and diet volume increased with the body size of both adult and juvenile bullfrogs.The diet composition of primary preys of bullfrogs was significantly different among the islands.The results indicate that bullfrogs exert different predatory influences on native fauna at different sites and that bullfrogs are generalist predators with extensive ecological impacts on native fauna.