Seroprevalence of anti-Neospora caninum antibodies in sheep from the rapidly expanding flock of Rio de Janeiro, Brazil.

Neosporosis is primarily a disease of cattle and dogs, but Neospora caninum has been linked to abortion and neonatal mortality in sheep. Since the economic, clinical and epidemiological importance of the infection in sheep remains uncertain, this work investigated the seroprevalence of anti-N. caninum antibodies and associated factors in the rapidly expanding flock of Rio de Janeiro state. Blood samples from 388 sheep of 12 farms were collected and sera tested by a commercial Enzyme-Linked Immunosorbent Assay. Seroprevalence at the animal-level was of 6.2% (24/388) and, at the herd-level, 50% (6/12) of the studied farms had at least one seropositive animal. Multivariate analysis detected that occasional veterinary assistance (P < 0.05) was significantly associated to higher seroprevalence, which is also associated to age (P < 0.001) and gender (P < 0.0001). Farmers' investments should focus on making technical assistance more frequent and future studies should assess the association of veterinary assistance with anti-N. caninum antibodies in sheep flocks.

Colour-Doppler ultrasound imaging as a laparoscopy substitute to count corpora lutea in superovulated sheep.

This study evaluated colour-Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty-five Santa Ines ewes were superovulated three times at 21-day intervals. Corpora lutea were counted by colour-Doppler UI (CLDOPPLER ) 6 days after each superovulation and confirmed by laparoscopy (CLLAP ) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CLDOPPLER and CLLAP , respectively) with a significant positive correlation (r = .94; r2 =.89). Colour-Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation.

Potential differences between Leptospira serovars, host-adapted (Bratislava) and incidental (Copenhageni), in determining reproductive disorders in embryo transfer recipient mares in Brazil.

The objective was to investigate potential differences between two Leptospira serovars, host-adapted (Bratislava) and incidental (Copenhageni), in causing reproductive disorders in mares. From August 2009 to March 2011, 608 adult recipient mares from eight studs located in the state of Rio de Janeiro, Brazil, were screened for leptospirosis. These mares were 3-8 years of age, of various breeds, and were managed in a semiextensive system (embryo transfer centres). According to the reproductive history of these mares, the studs were categorised as Group A (357 mares: high prevalence of reproductive problems), and Group B (251 mares: all pregnant). Of the 608 samples tested serologically, 273 (44.9 per cent) were reactive (titres ≥200), predominantly against Bratislava (62.3 per cent of reactive mares). In Group A, 247/357 sera (69.2 per cent) were reactive, with reactivity against Bratislava (64.8 per cent of reactive). By contrast, in Group B, only 26/251 sera (10.4 per cent) were reactive, the majority against Copenhageni (61.5 per cent of reactive). Seroreactivity against Bratislava was more likely to be associated (P<0.001) with reproductive problems than seroreactivity against Copenhageni; this association was true for early embryonic death (P<0.001), perinatal death (P<0.01), and abortion (P<0.001). Additionally, 29 urine samples were collected (from Group A mares) for Leptospira species PCR, of which 16 were positive (55.2 per cent). We concluded that leptospirosis was associated with poor reproductive performance in embryo recipients, with the majority due to host-adapted Bratislava.