摘要
以9株人肠道病原菌(致病大肠杆菌3株、志贺氏菌3株、沙门氏菌3株)制备的混合抗原对孕牛进行系统免疫,以获得对人致病肠道杆菌具有特异性的牛乳抗体。对母牛进行系统免疫后,免疫乳和非免疫乳中IgG总含量没有显著变化。但经免疫处理的母牛,其初乳(产犊后24h内)中针对9种致病肠道杆菌的特异性IgG效价为210-212,而非免疫母牛为27～210,免疫处理后初乳中特异性IgG效价提高了2-9倍;经免疫处理的母牛,其常乳中针对9种致病肠道杆菌的特异性IgG效价为26-210,而非免疫母牛为21-26,免疫处理后常乳中特异性IgG效价提高了8-14倍。对免疫乳中IgG热致变性进行研究,其结果为:经60℃、10min,60℃、30min,70℃、10min,70℃、30min,80℃、10min,80℃、30min加热处理,免疫乳中IgG变性率分别为14.81％、25.20％、76.44％、85.58％、100％、100％。对免疫乳中IgG酸稳定性进行研究,其结果为:经pH2、10min,pH2、30min,pH4.5、60min,PH4.5、120min处理,免疫乳中IgG活性持留率分别为66.69％、56.55％、100％、100％。
Objective: Selecting 3 strains pathogenic E. coli, 3 strains Salmonella and 3 strains Shigella as antigens to make the mixed vaccine, and gestation cows were immunized systemically. We can prepare immune milk with 9 milk antibodies. Methods: Experimental cows were immunized systemically three times before parturition and after parturition they were immunized systemically three times again. After parturition we collected the milk and researched the change of the total IgG and specific IgC in the milk. We also researched the change of the total IgC after the heat treatment and acidity treatment. Results: The antibody tilers against 9 pathogenic bacteria in immune colostrums were 210-212, 2-9 folds of control regular colostrums. The antibody titers against 9 pathogenic bacteria in immune milk were 26 - 210, 8 - 14 folds of control regular milk. The denaturalion percentages of IgG after treatment at 60℃10min, 60℃30min, 70℃ 10min, 70℃ 30min, 80℃10min, 80℃ 30min were 14.81%, 25.20%, 76.44%, 85. 58%, 100%, 100%, respectively. The retain percentages of IgG after treatment at pH2 10min, pH2 30min, pH4. 5 60min, pH4. 5 120min were 66. 69%, 56. 55%, 100%, 100%, respectively. Conclusion: Immunized sys-lemically could not increase the concentration of total IgG in the immune milk, but significantly heighten the specificity IgG of immune milk.
