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981.
982.
Vishwanath S.J. Kolte M.P. Singh R.P. Awasthi 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(2):217-220
Resistance in susceptible mustard cv. PR-15 against the highly virulent A. brassicae isolate A (AbA) and moderately virulent isolate C (AbC) was induced using an avirulent Alternaria brassicae isolate D (AbD). The induction of resistance due to AbD against AbA or AbC resulted in significant reduction in disease severity. The A. alternata (Aa) failed to induce resistance against AbA and AbC, on the contrary it induced susceptibility against them. 相似文献
983.
984.
Positive correlation between Aeromonas salmonicida vaccine antigen concentration and protection in vaccinated rainbow trout Oncorhynchus mykiss evaluated by a tail fin infection model 下载免费PDF全文
M H Marana J Skov J K Chettri B Krossøy I Dalsgaard P W Kania K Buchmann 《Journal of fish diseases》2017,40(4):507-516
Rainbow trout, Oncorhynchus mykiss (Walbaum), are able to raise a protective immune response against Aeromonas salmonicida subsp. salmonicida (AS) following injection vaccination with commercial vaccines containing formalin‐killed bacteria, but the protection is often suboptimal under Danish mariculture conditions. We elucidated whether protection can be improved by increasing the concentration of antigen (formalin‐killed bacteria) in the vaccine. Rainbow trout juveniles were vaccinated by intraperitoneal (i.p.) injection with a bacterin of Aeromonas salmonicida subsp. salmonicida strain 090710‐1/23 in combination with Vibrio anguillarum serotypes O1 and O2a supplemented with an oil adjuvant. Three concentrations of AS antigens were applied. Fish were subsequently challenged with the homologous bacterial strain administered by perforation of the tail fin epidermis and 60‐s contact with live A. salmonicida bacteria. The infection method proved to be efficient and could differentiate efficacies of different vaccines. It was shown that protection and antibody production in exposed fish were positively correlated to the AS antigen concentration in the vaccine. 相似文献
985.
Biochemical changes and tissue distribution of Enterocytozoon hepatopenaei (EHP) in naturally and experimentally EHP‐infected whiteleg shrimp,Litopenaeus vannamei (Boone, 1931), in India 下载免费PDF全文
S Santhoshkumar S Sivakumar S Vimal S Abdul Majeed G Taju P Haribabu A Uma A S Sahul Hameed 《Journal of fish diseases》2017,40(4):529-539
Stunted growth in pond‐reared Litopenaeus vannamei was observed in different farms located in Tamil Nadu and Andhra Pradesh, India. No mortality was associated with stunted growth. PCR assay on these samples revealed the presence of Enterocytozoon hepatopenaei (EHP) in stunted shrimp. Tissue distribution of EHP in naturally and experimentally infected shrimp was studied by PCR and histology. Histological examination revealed the presence of EHP in hepatopancreas and gut, but not in other organs. The PCR assay revealed the presence of EHP in all the organs tested in both naturally and experimentally infected shrimp. Healthy shrimp were challenged with E. hepatopenaei by intramuscular injection and oral route, and no mortality was observed in both routes after 30 days post‐challenge. Different developmental stages of the microsporidian parasite were observed in the hepatopancreatic epithelial cells. Biochemical parameters such as total protein, albumin, aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase were measured in the haemolymph of naturally and experimentally EHP‐infected shrimp. All biochemical parameters mentioned were found to be significantly higher in EHP‐infected shrimp when compared to normal shrimp. This is the first report relating AST and ALT levels to EHP infection in naturally and experimentally infected shrimp. 相似文献
986.
Nonspecific responses of Japanese eels to environmental stress were monitored by assaying various lytic activities in eel epidermal extract. In fish maintained at 10 and 30 °C for up to 10 days, epidermal proteolytic activities due to serine protease and aminopeptidase and hemolytic activity varied within a 2-fold value range. Other proteolytic activities, due to cathepsins B and L, in the fish at 30 °C increased for up to 8 days and were 3.4 and 2.9-fold over those in fish maintained at 10 °C, respectively. This was accompanied by a 3.0-fold increase in bacteriolytic activity. Other forms of stress were exerted on the fishes by immersing them in a suspension of Flavobacterium columnare or giving them intraperitoneal injections of Edwardsiella tarda over 72 h. Although serine protease and aminopeptidase activities and hemolytic activity in the fishes exposed to F. columnare changed marginally, and were similar to those in the control fish, cathepsins B and L activities in the infected fishes increased more than 1.5-fold over their initial values over a 48 h period, along with a 4.5-fold increase in bacteriolytic activity. No marked change was detected in any of the lytic activities of the fishes exposed to E. tarda. These findings indicate that epidermal cathepsins B and L probably participate in bacteriolysis associated with Japanese eel skin and that their activities are elicited by environmental stimuli and may be an important nonspecific response of eels. Abbreviations: Cbz – carbobenzoxy; MCA – 4-methylcoumaryl-7-amide. 相似文献
987.
988.
Hideko KAMEYAMA Yoshikazu FUJIMOTO Yukiko TOMIOKA Sayo YAMAMOTO Haruka SUYAMA Hiromi INOUE Eiki TAKAHASHI Etsuro ONO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(4):574
Bordetella bronchiseptica (B. bronchiseptica) is associated with respiratory tract infections in laboratory animals. In our laboratory animal facility, B. bronchiseptica was isolated from 21 of 27 apparently healthy rabbits obtained from a breeding farm contaminated with B. bronchiseptica. Restriction fragment length polymorphism (RFLP) analysis showed that the flagellin genotype of isolates from the laboratory animal facility and breeding farm was type A, which is seen relatively frequently in rabbits in Europe. To examine its pathogenicity, guinea pigs, rats, and mice were inoculated intranasally with a representative strain isolated in the laboratory animal facility. Following inoculation of 107 colony forming unit (cfu), severe inflammation was observed in the lungs of guinea pig and mice, although the inflammation was less severe in rats. The strain was recovered from the trachea and lungs of these species after inoculation with lower dose such as 103 or 104 cfu. These results suggest that the isolated strain causes respiratory tract infection in guinea pigs, rats, and mice, and that its pathogenicity higher in mice than in rats. This study extends our knowledge of interpreting the microbiologic status of laboratory animals, which will contribute to the development of reliable and reproducible animal experiments. 相似文献
989.
990.
猪衣原体病的调查 总被引:4,自引:2,他引:4
1986-2002年从全国17个省部分猪场收集猪血清17448份,用间接血凝试验(IHA)检测猪衣原体抗体,其中青海猪衣原体抗体阳性检出率为33.3%和42.9%,四川11.5%和80.0%,新疆22.2%,陕西38.0%。广西21.2%。云南24.5%。广东50.2%。甘肃42.2%和36.0%。河南35.1%和18.2%。宁夏15.1%,海南38.2%,湖北37.5%,湖南16.7%。江西50.0%,辽宁43.2%。黑龙江77.1%,吉林20.5%。并从一些省区所采的流产胎儿,流产母猪阴道拭子,仔猪肺炎死亡病例病料分离到鹦鹉热衣原体。从东北三省猪群检出衣原体抗体在国内属首次报道。 相似文献