Abortions and stillbirths in goats immunized against brucellosis | Presencia de aborto y mortinatos en cabras inmunizadas

Inglés. The presence of abortions was evaluated in brucellosis-vaccinated goats in endemic zones. In total, 243 goats under extensive management conditions were used, 57 goats were vaccinated with RB51 at the dose rate of 1 x 1010 colony-forming units (cfu)/ml, 68 goats received 1 x 109 cfu rfbK, 97 goats received 1 x 105 cfu Rev 1, and 21 goats were kept as non-vaccinated controls. One hundred thirty nine (139) goats were detected pregnant, resulting in the following pregnancy rates: 40.3 % (23/ 57) for RB51, 66.2 % (45/68) rfbK, 46.4 % (45/97) for Rev 1, and 85.7 % (18/21) for the non-vaccinated controls. Abortion rates were as follows: RB51: 74.1 % (23/31), rfbK: 35.5 % (16/45), Rev 1: 22.2 % (0/45), and non-vaccinated controls: 16.6% (3/18). The RB51 strain was isolated from one aborted fetus. The relative risk of abortion was as follows: RB51: 4.45, rfbK: 2.13, and Rev 1: 1.33. In addition, goats in a herd with excellent nutritional conditions were also vaccinated, as follows: 10 with 1 x 1010 cfu RB51, 10 with 1 x 109 cfu rfbK, 10 with 1 x 105 cfu Rev 1, and 9 goats remained as non-vaccinated controls. The RB51 group had one abortion and one stillborn kid. In both cases, the RB51 strain was isolated from the fetuses and vaginal exudates. It was concluded that among the immunogens evaluated in goats, the RB51 strain vaccine is not an adequate option, since it results in abortions and stillbirths.

Español; castellano. Se evaluó la presencia de abortos en cabras vacunadas contra brucelosis en zonas endémicas. Se trabajó con 243 cabras en explotaciones extensivas, 57 fueron vacunadas con RB51 a una dosis de 1 x 1010 ufc/ml, 68 cabras con rfbK a 1 x 109 ufc, 97 cabras con Rev 1 a 1 x 105 ufc y 21 cabras sin vacunar. Se detectaron gestantes a 139 cabras, los porcentajes de gestación fueron: 40.3 % (23 de 57) para RB51, 66.2 % (45 de 68) de rfbK, 46.4 % (45 de 97) para Rev 1 y en las no vacunadas 85.7 % (18 de 21). Los porcentajes de abortos fueron para RB51 de 23/31 (74.1 %), para rfbK de 16/45 (35.5%), para Rev 1 de 10/ 45 (22.2 %) y en el grupo no vacunado 3/18 (16.6 %), se logró aislar la cepa RB51 de un feto abortado. El riesgo relativo de presentar abortos en el grupo con RB51 fue de 4.45, con rfbK de 2.13 y con Rev 1 de 1.33. Además se vacunaron cabras gestantes de un rebaño con excelentes condiciones nutricionales, 10 con RB51 a una dosis de 1 x 1010 ufc, 10 con rfbK a 1 x 109 ufc, diez con Rev 1 y nueve cabras sin vacunar. El grupo de RB51 presentó un aborto y un mortinato, en ambos casos RB51 fue aislada de los fetos y exudados vaginales. Se concluye que entre los inmunógenos evaluados en cabras, la RB51 no es una opción conveniente ya que es causa de abortos y de mortinatos.