Epidemiological Evaluation of Reproductive Infectious Agents in Sheep in the Brazilian Semiarid

Abstract

The aim of this work was to identify sheep herds with history of reproductive failures (abortions and perinatal mortality) associated to presence of Chamydophila abortus, Brucella ovis and Leptospira spp. infections in the semiarid region of Northeastern Brazil. Blood samples were collected from 476 animals from 72 herds in 14 counties of the Sertão mesoregion, state of Paraíba. For the serological diagnosis of C. abortus, B. ovis and Leptospira spp. infections, complement fixation test (CFT), agar gel immunodiffusion test (AGID) and microscopic agglutination test (MAT) were used, respectively. Herd-level prevalence (herds with at least one seropositive animal) of C. abortus was 52.8%, followed by B. ovis (33.3%) and Leptospira spp. (27.7%); concerning seropositivity in animals there was also a higher frequency of C. abortus (19.7%), followed by B. ovis (12.1%) and Leptospira spp. (7.6%) (p < 0.05). Herds with history of abortion (31.9%; 23/72) and perinatal mortality (54.2%; 39/72) had at least one sheep seropositive to one of the infectious agentes. For abortions, herd-level prevalence of C. abortus was 60.8%, followed by B. ovis (43.4%) and Leptospira spp. (30.4%). For perinatal mortality, herd-level prevalence was 64.1% for C. abortus, 38.4% for B. ovis and 33.3% for Leptospira spp. It is suggested that these agents may be important causes of reproductive failures in the semiarid region, and, thus, it is recommended that herd owners should be informed on reasonable sanitary measures related to animal health, and advised to perform diagnosis in cases of abortion and perinatal mortality. Keywords: Reproduction diseases, small ruminants, epidemiology, control, Northeastern Brazil. Read more →