The aim of this study was to evaluate the factors influencing the inactivation effect of intense pulsed light(IPL)on Aeromonas salmonicida grown on chicken meat and skin,and to further develop prediction models of ina...The aim of this study was to evaluate the factors influencing the inactivation effect of intense pulsed light(IPL)on Aeromonas salmonicida grown on chicken meat and skin,and to further develop prediction models of inactivation.In this work,chicken meat and skin inoculated with meat-borne A.salmonicida isolates were subjected to IPL treatments under different conditions.The results showed that IPL had obvious bactericidal effect in the chicken skin and thickness groups when the treatment voltage and time were 7 V combined with 5 s.In addition,the lethality curves of A.salmonicida were fitted under IPL conditions of 3.5-7.5 V.The comparison of statistical parameters revealed that the Weibull model could best fit the mortality curves and could accurately predict the mortality dynamic of A.salmonicida grown on chicken skin.And further a secondary model between the scale factor b and the treatment voltage in Weibull model was established using linear equations,which determined that the secondary model could accurately predict the inactivation of A.salmonicida.This study provides a theoretical basis for future prediction models of Aeromonas,and also provides new ideas for sterilization approaches of meat-borne Aeromonas.展开更多
Vibrio scophthalmi and Aeromonas salmonicida can cause high turbot mortality and huge economic losses.Presently,vaccination is the most promising method for preventing communicable diseases.In this study,we used forma...Vibrio scophthalmi and Aeromonas salmonicida can cause high turbot mortality and huge economic losses.Presently,vaccination is the most promising method for preventing communicable diseases.In this study,we used formalin to kill V.scophthalmi and A.salmonicida cells,and mixed with the mineralized oil adjuvant(Montanide^(TM)ISA 763 AVG)to prepare the bivalent inactivated vaccine.The results showed that turbot inoculated with the bivalent inactivated vaccine exhibited strong tolerance to the infection of V.scophthalmi and A.salmonicida,and no obvious clinical symptoms and pathological changes were observed.The activities of enzymes lysozyme,acid phosphatase and complement C3 had significantly increased after the vaccination.The antibody titer response of vaccinated turbot was greatly boosted,which was positively connected with the immunological impact according to ELISA results.Simultaneously,the expression levels of immune-related genes such as MHC-IIα,MHC-IIβ,CD4,CD8,TNF-αand IL^(-1)βwere up-regulated,demonstrating that it might stimulate humoral and cellular immunological response in turbot.These findings highlight the potential of the bivalent inactivated vaccine for controlling V.scophthalmi and A.salmonicida infections in turbot.展开更多
Aim of this research was to find out the concentration of enrofloxacin residue in tilapia meat for several weeks after antibiotic treatment. Twenty seven tilapia fishes were divided into three groups. The first group ...Aim of this research was to find out the concentration of enrofloxacin residue in tilapia meat for several weeks after antibiotic treatment. Twenty seven tilapia fishes were divided into three groups. The first group was not infected and treated, the second group was infected with A. salmonicida subsp, smithia and the third group was infected with A. salmonicida subsp. achromogenes intramuscularly. Six days after infection, treatment was carried out using Baytril administered orally for the second group and intramuscularly for the third group during five days. At the 1 st, 4th and 8th week after the treatment, Three fish were taken from each group to be analyzed for its concentration of enrofloxacin residue by diffusion on Mueller Hinton Agar （MHA） method and quantitatively using high performance liquid chromatography （HPLC） method. The MHA test showed the formation of inhibition zone, at the 1 st week and 4th week after the treatment, while at 8th week after treatment did not show inhibition zone. The HPLC test on enrofloxacin residual concentration in tilapia infected with A. salmonicida subsp, smithia （second group） at the 1st, 4th and 8th week after treatment showed the average of 33.0, 6.10 and 0.0021 μg/g of enrofloxacin residue level. While in tilapia infected with A. salmonicida subsp, achromogenes and treated with enrofloxacin intramuscularly （third group） showed the average of residue level 35.79, 2.18 and 0.00065 μg/g. In conclusion, the residue of enrofloxacin was still high concentration until the fourth week after treatment in the second and third groups. Based on Indonesian National Standards and Rules, the maximum limit of enrofloxacin residue is 0.01 μg/g. The concentration of enrofloxacine residue was very low and the concentration of enrofloxacin residue collected from tilapia using orally and intramuscularly method of treatment was not different.展开更多
Aeromonas spp.are commonly found in spoilage of chilled meat.Aeromonas salmonicida NCM 29 and A.salmonicida NCM 57 have been discovered the spoilage heterogeneity in degrading myofibrillar protein.In this study,the tw...Aeromonas spp.are commonly found in spoilage of chilled meat.Aeromonas salmonicida NCM 29 and A.salmonicida NCM 57 have been discovered the spoilage heterogeneity in degrading myofibrillar protein.In this study,the two strains were tested to uncover the discrepancy of meat spoilage in collagen-rich chilled meat and extracted collagen.The results revealed that chicken claws,riched in collagen,inoculated with NCM 29 showed higher values of total viable counts(TVC),total volatile basic nitrogen(TVB-N),pH,adhered cells,trichloroacetic acid(TCA)-soluble peptides,and protease activity compared to those inoculated with NCM 57.Furthermore,NCM 29 generated higher quantity of volatile organic compounds related to meat spoilage.The collagenase((hemagglutinin protease(Hap))secreted by NCM 29 has been identified as the key factor responsible for the observed discrepancies in spoilage,which gradually degraded collagen into peptides and hydroxyproline.The capacity of Hap to degrade type Ⅰ collagen in vitro indicated that it has apparent proteolytic activity,which could reduce the average particle size and alter secondary structure of collagen.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)further confirmed the degradation of theβ-chain in collagen.These findings not only provide a theoretical basis for in-depth investigation of the meat spoilage mechanisms of Aeromonas spp.,but also encourage us to take measures to avoid the spoilage of related bacteria such as Aeromonas spp.during the preservation process.展开更多
【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长...【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长度1 446 bp,Gen Bank登录号为JX164202)与其它杀鲑气单胞菌16S r RNA基因一致性在99%-100%之间,构建发育树确定该菌株为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp.salmonicida)。人工回感可导致异育银鲫死亡。药敏试验结果显示:对头孢呋辛、复方新诺明、恩诺沙星等23种抗生素敏感;对阿米卡星、四环素、大观霉素、头孢拉定等11种抗生素中度敏感;对青霉素G、链霉素、庆大霉素、氟苯尼考、万古霉素等10种抗生素耐药。【结论】研究结果证实引起异育银鲫死亡的病原为杀鲑气单胞菌杀鲑亚种。展开更多
利用 A 值法与活菌平板计数法,测定了杀鲑气单胞菌在不同条件下的生长曲线,研究了不同温度及pH对杀鲑气单胞菌（Aeromonas salmonicha）生长的影响。结果表明,活菌计数法更能真实的反映细菌数量的动态变化。在28℃,15℃,10℃,5℃条件下...利用 A 值法与活菌平板计数法,测定了杀鲑气单胞菌在不同条件下的生长曲线,研究了不同温度及pH对杀鲑气单胞菌（Aeromonas salmonicha）生长的影响。结果表明,活菌计数法更能真实的反映细菌数量的动态变化。在28℃,15℃,10℃,5℃条件下,随着温度降低,杀鲑气单胞菌生长速率明显下降；在pH6.0-8.0时,酸性条件能明显抑制杀鲑气单胞菌的生长；在28℃、pH7.5条件下,杀鲑气单胞菌生长速率最快,达到稳定期时细菌数量也最多。在养殖生产过程中,为了抑制杀鲑气单胞菌的生长繁殖,建议在不影响鱼类正常生长的条件下,尽量降低养殖水体温度并合理控制水体pH,以降低养殖鱼类发病率。展开更多
基金supported by projects funded by grants from the Natural Science Foundation of Jiangsu Province in China(BK20221515)the National Natural Science Foundation of China(32172266)the Changzhou Science and Technology Support Program(CE20222002)。
文摘The aim of this study was to evaluate the factors influencing the inactivation effect of intense pulsed light(IPL)on Aeromonas salmonicida grown on chicken meat and skin,and to further develop prediction models of inactivation.In this work,chicken meat and skin inoculated with meat-borne A.salmonicida isolates were subjected to IPL treatments under different conditions.The results showed that IPL had obvious bactericidal effect in the chicken skin and thickness groups when the treatment voltage and time were 7 V combined with 5 s.In addition,the lethality curves of A.salmonicida were fitted under IPL conditions of 3.5-7.5 V.The comparison of statistical parameters revealed that the Weibull model could best fit the mortality curves and could accurately predict the mortality dynamic of A.salmonicida grown on chicken skin.And further a secondary model between the scale factor b and the treatment voltage in Weibull model was established using linear equations,which determined that the secondary model could accurately predict the inactivation of A.salmonicida.This study provides a theoretical basis for future prediction models of Aeromonas,and also provides new ideas for sterilization approaches of meat-borne Aeromonas.
基金supported by the Fish Innovation Team of Shandong Agriculture Research System (No. SDAIT-1206)the Aquatic Animal Immunologic Agents Engineering Research Center of Shandong Province, the Qingdao Agricultural University Doctoral Start-Up Fund (6631122030)+5 种基金the National Natural Science Foundation of China (No. 32002421)the Advanced Talents Foundation of QAU (No. 6651118016)the Natural Science Foundation of Shandong Province (No. ZR2019BC009)the ‘First-Class Fishery Discipline’ program of Shandong Province, the special top talent plan ‘One Thing One Decision (Yi Shi Yi Yi)’the Key Research and Development Program in Shandong Province (No. 2018YFJH0703)Breeding Plan of Shandong Provincial Qingchuang Research Team (2019)
文摘Vibrio scophthalmi and Aeromonas salmonicida can cause high turbot mortality and huge economic losses.Presently,vaccination is the most promising method for preventing communicable diseases.In this study,we used formalin to kill V.scophthalmi and A.salmonicida cells,and mixed with the mineralized oil adjuvant(Montanide^(TM)ISA 763 AVG)to prepare the bivalent inactivated vaccine.The results showed that turbot inoculated with the bivalent inactivated vaccine exhibited strong tolerance to the infection of V.scophthalmi and A.salmonicida,and no obvious clinical symptoms and pathological changes were observed.The activities of enzymes lysozyme,acid phosphatase and complement C3 had significantly increased after the vaccination.The antibody titer response of vaccinated turbot was greatly boosted,which was positively connected with the immunological impact according to ELISA results.Simultaneously,the expression levels of immune-related genes such as MHC-IIα,MHC-IIβ,CD4,CD8,TNF-αand IL^(-1)βwere up-regulated,demonstrating that it might stimulate humoral and cellular immunological response in turbot.These findings highlight the potential of the bivalent inactivated vaccine for controlling V.scophthalmi and A.salmonicida infections in turbot.
文摘Aim of this research was to find out the concentration of enrofloxacin residue in tilapia meat for several weeks after antibiotic treatment. Twenty seven tilapia fishes were divided into three groups. The first group was not infected and treated, the second group was infected with A. salmonicida subsp, smithia and the third group was infected with A. salmonicida subsp. achromogenes intramuscularly. Six days after infection, treatment was carried out using Baytril administered orally for the second group and intramuscularly for the third group during five days. At the 1 st, 4th and 8th week after the treatment, Three fish were taken from each group to be analyzed for its concentration of enrofloxacin residue by diffusion on Mueller Hinton Agar （MHA） method and quantitatively using high performance liquid chromatography （HPLC） method. The MHA test showed the formation of inhibition zone, at the 1 st week and 4th week after the treatment, while at 8th week after treatment did not show inhibition zone. The HPLC test on enrofloxacin residual concentration in tilapia infected with A. salmonicida subsp, smithia （second group） at the 1st, 4th and 8th week after treatment showed the average of 33.0, 6.10 and 0.0021 μg/g of enrofloxacin residue level. While in tilapia infected with A. salmonicida subsp, achromogenes and treated with enrofloxacin intramuscularly （third group） showed the average of residue level 35.79, 2.18 and 0.00065 μg/g. In conclusion, the residue of enrofloxacin was still high concentration until the fourth week after treatment in the second and third groups. Based on Indonesian National Standards and Rules, the maximum limit of enrofloxacin residue is 0.01 μg/g. The concentration of enrofloxacine residue was very low and the concentration of enrofloxacin residue collected from tilapia using orally and intramuscularly method of treatment was not different.
基金supported by projects funded by grants from the Natural Science Foundation of Jiangsu Province in China(BK20221515)the National Natural Science Foundation of China(32172266).
文摘Aeromonas spp.are commonly found in spoilage of chilled meat.Aeromonas salmonicida NCM 29 and A.salmonicida NCM 57 have been discovered the spoilage heterogeneity in degrading myofibrillar protein.In this study,the two strains were tested to uncover the discrepancy of meat spoilage in collagen-rich chilled meat and extracted collagen.The results revealed that chicken claws,riched in collagen,inoculated with NCM 29 showed higher values of total viable counts(TVC),total volatile basic nitrogen(TVB-N),pH,adhered cells,trichloroacetic acid(TCA)-soluble peptides,and protease activity compared to those inoculated with NCM 57.Furthermore,NCM 29 generated higher quantity of volatile organic compounds related to meat spoilage.The collagenase((hemagglutinin protease(Hap))secreted by NCM 29 has been identified as the key factor responsible for the observed discrepancies in spoilage,which gradually degraded collagen into peptides and hydroxyproline.The capacity of Hap to degrade type Ⅰ collagen in vitro indicated that it has apparent proteolytic activity,which could reduce the average particle size and alter secondary structure of collagen.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)further confirmed the degradation of theβ-chain in collagen.These findings not only provide a theoretical basis for in-depth investigation of the meat spoilage mechanisms of Aeromonas spp.,but also encourage us to take measures to avoid the spoilage of related bacteria such as Aeromonas spp.during the preservation process.
文摘【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长度1 446 bp,Gen Bank登录号为JX164202)与其它杀鲑气单胞菌16S r RNA基因一致性在99%-100%之间,构建发育树确定该菌株为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp.salmonicida)。人工回感可导致异育银鲫死亡。药敏试验结果显示:对头孢呋辛、复方新诺明、恩诺沙星等23种抗生素敏感;对阿米卡星、四环素、大观霉素、头孢拉定等11种抗生素中度敏感;对青霉素G、链霉素、庆大霉素、氟苯尼考、万古霉素等10种抗生素耐药。【结论】研究结果证实引起异育银鲫死亡的病原为杀鲑气单胞菌杀鲑亚种。
文摘利用 A 值法与活菌平板计数法,测定了杀鲑气单胞菌在不同条件下的生长曲线,研究了不同温度及pH对杀鲑气单胞菌（Aeromonas salmonicha）生长的影响。结果表明,活菌计数法更能真实的反映细菌数量的动态变化。在28℃,15℃,10℃,5℃条件下,随着温度降低,杀鲑气单胞菌生长速率明显下降；在pH6.0-8.0时,酸性条件能明显抑制杀鲑气单胞菌的生长；在28℃、pH7.5条件下,杀鲑气单胞菌生长速率最快,达到稳定期时细菌数量也最多。在养殖生产过程中,为了抑制杀鲑气单胞菌的生长繁殖,建议在不影响鱼类正常生长的条件下,尽量降低养殖水体温度并合理控制水体pH,以降低养殖鱼类发病率。
