幼畜腹泻双价基因工程苗对牛和羊的攻毒保护试验

STUDIES ON PROTECTING CALF AND LAMB AGAINST PATHOGENIC BACTERIUM TEST WITH DIVALENT GENETIC ENGINEERING VACCINE PREVENTING INFANTILE DIARRHEA

用幼畜腹泻双价基因工程苗以两种剂量（正常免疫剂量和1／2免疫剂量）分别免疫接种怀孕母牛和怀孕母羊，待其分娩并保证其所产幼畜（犊牛、羔羊）采食初乳后，经口灌服致幼畜腹泻的强毒活菌。结果，正常免疫剂量组，犊牛腹泻发病率为14．3％，死亡率为零；羔羊腹泻发病率为15．8％，死亡率为2．7％。1／2免疫剂量组，犊牛腹泻发病率为30．7％，死亡率为10．3％；羔羊腹泻发病率为24．4％，死亡率为12．2％。未接种疫苗的对照组，犊牛腹泻发病率为83．3％，死亡率为44．4％；；，羔羊腹泻发病率为78．9％，死亡率为57．8％。经统计学处理，三组之间犊牛和羔羊的发病率和死亡率均是极显著差异（P＜0．01）。

The pregnant cows and sheep were vaccinated with diavalent genetie engineering vaccine in two kinds of dose separately (normal dose and half-normal dose) to prevent infantile diarrhea. After feeding colostral balk from the dams, thnewborn calves and lambwere taken orally pathogenic bacterium producing infantile diarrhea. It was shown that thecalves diarrhea attack rate and death rate were 14. 3% and 10% separately, the lamb diarrhea attack rate and death rate were 15. 8% and 2. 7% separately in the normal group; thecalves diarrhea attack rate and death rate were 30. 7% and 10. 3% separately, the lamb diarrhea attack rate and death rate were 24. 4% and 12. 2% separately in the half normal dosegroup; and in the control group without vaccinating, the calves diarrhea attack rate anddeath rate were 83. 3% and 44. 4% separately, the lamb diarrhea attack rate and death ratewere 78. 9% and 57. 8% separately. There was a significant difference (p<0.01) among theattack rate and death rate of the 3 groups by statistical comparision.