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Update Date: [2022-10-05]

Publication Field trlals of poly-valent bacterins for erysipelas control-evaluation of immunity effects on pigs vaccinated with erysipelas vaccines with feed containing antimicrobial additives


Reportno.

AHRI report No.33

Topic

Field trlals of poly-valent bacterins for erysipelas control-evaluation of immunity effects on pigs vaccinated with erysipelas vaccines with feed containing antimicrobial additives

Department

1.Department of Biological Products Research, Taiwan Animal Health Research Institute.
2.Chia-Yi Hsien Livestock Disease Control Center Tay-Pao

Author Ching-Chuan Lu 1, Ching Chen*1, Jiun-Shyong Lai1, Hao-Jan Ko1, Nae-Wei Guo1 and I-Po Chan' Chi-Ming Yeh2, Wen-Chang Chang2, Hwng-Meng Hsiaw2, Maw-Jenn Chen2, Lan-how Chiu2, and Jen-Sung Lo2• 
Summary

The geometric mean titer (GMT) of the growth agglutination (GA) titers of swin.., vaccinated with attenuated Erysipelas vaccine against la serotype strain isolated in TaiwAn were round to be 1 : 16, 1 : 14.9, and 1 : 19.7, respectively, at 3, 6, and 12 weeks after vaccination in feeding condition with feed containing 1.2 kg/ ton of SP-500 additive. Those GA titers were distinguishable from the counterparts measured, respectively, 1 : 7, 1 : 9.2, and 1 : 7 from the group of pigs inoculated with inactived bacterin under the same feeding condition. It indicated that the immunity abilities of the pigs immunized with attenuated vaccine were not affected by that antimicrobial additive. 

On the other hand, two groups of pigs were fed with Amoxicillin 0.3 kg + Chloramphenicol 1.0 kg per ton additives. The GMT of the GA titers were 1 : 9.8, 1 : 7.5, and 1 : 7 for the group of pigs immunized with attenuated vaccine. Compared to the GMT of the GA titers of 1 : 7, 1 : 9.2, and 1 : 8 obtained from the group of pigs with inactivated bacterin vaccination under the same feed condition, the resulting GA titers were similar, Comparing the two groups of pigs inoculated with attenuated vaccine but fed with different additives, the immunity effects of the pigs were inhibited under the second feed condition. On the contrary, the GMT of the GA titers were at the same level under both feed conditions for the groups of pigs vaccinated with inactivated bacterin. 
Although the GA titers were low in all groups of pigs vaccinated with inactivated bacterin, the GMT titers were not distinctly different in the two additive groups tested. Based on the challenge exposure to virulent strain, the results indicated that all groups of pigs showed various degree of challenge reactions. In the end, except for one dead pig in the group with inactivated bacterin vaccination, the rest survived like the group of pigs vaccinated with attenuated vaccine. 

Keyword

Erysipelas, Attenuated vaccine, Inactivated vaccine, Antimicrobial additives, Growth agglutination titer.