Radial immunodiffusion test with native hapten in the differentiation of cattle with repeated Brucella abortus S19 strain revaccinations
The purpose of this study was to learn about the ability of radial immunodiffusion (RID) with a native hapten to differentiate vaccine-derived from infection-derived antibodies in cattle with repeated S19 strain revaccinations. The study was carried out in a dairy herd located in the state of Mexico, with experiencing abortions, placental retentions, stillbirths, and mummified fetuses. Heifer calves had been vaccinated at an early age with the classic dose rate of B. abortus S19 strain. Later, as adults, they received yearly repeated vaccinations with the reduced dose of the same vaccine. Some cows had received 2-6 revaccinations at the time of the study. Serum samples were obtained from all females (n = 300) at breeding age. Ninety (30 %) cows with reproductive problems were selected using cow records. Serum samples were analyzed using the card, rivanol, and native hapten RID tests. Milk and vaginal exudate samples were collected from these 90 cows with reproductive problems, for acteriological diagnosis. Out of the 300 cattle sampled, 157 (52.3 %) were positive to the card test, and 98 (32.6 %) were positive to the rivanol test. Out of the 91 cows with reproductive problems, 88 (97.37 %) cows were positive to the card test, 67 (74.4 %) cows were positive to the rivanol test, and 19 (21.1 %) cows were positive to the RID test. Seventeen (17) (89.4 %) out of the 19 RID-positive cows were considered as infected, since they were positive (1:200) to rivanol, while 2 (10 %) resulted negative to the rivanol test. Three biotype 1 B. abortus strains were isolated from milk samples. It was concluded that the RID test is useful to discriminate infected cattle from those that have been repeatedly revaccinated with reduced S19 vaccine doses.
| Main Authors: | , , |
|---|---|
| Format: | Digital revista |
| Language: | spa |
| Published: |
Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias
2012
|
| Online Access: | https://cienciaspecuarias.inifap.gob.mx/index.php/Pecuarias/article/view/1742 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|