This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using convention...This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.展开更多
Three different treatment methods, including topical application method, injection method and immersion method were employed to treat 17or - hydroxyprogesterone, so as to investigating its effect on ovarian developmen...Three different treatment methods, including topical application method, injection method and immersion method were employed to treat 17or - hydroxyprogesterone, so as to investigating its effect on ovarian development red swamp crayfish （Procambarus clarkii）. The results showed that all the three differ- ent methods could facilitate the synchronous ovarian development of red swamp crayfish at different degree, with the degree of maturity of 10% high compared with the control group. The highest maturity degree was 50% that was observed in immersion treatment group. The effect was determined as in order immersion method 〉 injection method 〉 topical apphcation method 〉 control group. The immersion method and the injection method could facilitate synchronization spawning of red swamp crayfish, with the order of immersion method 32.5%, injection method 20%, topical application 17.5% and the control group 17.5 %. Taking the synchro- nization spawning rate, final spawning rate and mortality into account, the order was the immersion method 〉 injection method 〉 topical application method 〉 control group.展开更多
基金Supported by the Science and Technology Innovative Research Team of Anhui Academy of Agricultural Sciences(14C0504)the Youth Innovation Foundation of President of Anhui Academy of Agricultural Sciences(14B0529)Anhui Aquaculture Industry Technology System for Shrimp and Crab
文摘This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.
文摘Three different treatment methods, including topical application method, injection method and immersion method were employed to treat 17or - hydroxyprogesterone, so as to investigating its effect on ovarian development red swamp crayfish （Procambarus clarkii）. The results showed that all the three differ- ent methods could facilitate the synchronous ovarian development of red swamp crayfish at different degree, with the degree of maturity of 10% high compared with the control group. The highest maturity degree was 50% that was observed in immersion treatment group. The effect was determined as in order immersion method 〉 injection method 〉 topical apphcation method 〉 control group. The immersion method and the injection method could facilitate synchronization spawning of red swamp crayfish, with the order of immersion method 32.5%, injection method 20%, topical application 17.5% and the control group 17.5 %. Taking the synchro- nization spawning rate, final spawning rate and mortality into account, the order was the immersion method 〉 injection method 〉 topical application method 〉 control group.
