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The aim of this research was to determine the influence of Neospora caninum(NC) infection on reproductive parameters of Holstein dairy cows. The study was performed at 32 farms in the south of Brazil, latitude 27°30′S to 31°S and longitude 51°30′W to 55°30 W Farms included in this study met rigorous vaccination schedule for infectious bovine rhinotracheitis, bovine viral diarrhea virus, leptospirosis, and brucellosis. Blood samples collected from the dairy cows were submitted to serologic testing by an indirect fluorescent antibody test (IFAT) and were distributed into 2 groups: seropositive (GP; n= 160) and seronegative (GN; n= 558). The dogs (n= 51) of the farms were tested by IFAT. After abortion, fetuses were frozen at -80°C and submitted to PCR detection of NC in tissues. Seropositive cows that aborted were also tested by IFAT. Pregnancies of GP and GN cows were mon- itored by periodic ultrasound exams. After parturition or abortion all cows in GP and GN groups were submitted to gynecological exams. Cows that developed disease (clinical mastitis, metabolic disease, or laminitis) after parturition or abortion were excluded from the analysis to prevent any distortion of data. Farms were divided into 3 categories according to production technology, specifically, average milk production per cow per lactation: high (>25 kg), medium (15-25 kg), and low ( 0.05). The prevalence in dogs was 48.6% and did not differ among production systems. Fifty-nine (41.37%) NC-seropositive cows aborted. This differs significantly from the seronegative cow abortion rate (n= 17; 2.6%; P< 0.001). Occurrence of retained fetal membranes (RFM), endometritis, absence of uterine infection after abortion, and days between abortion and first estrus can be observed in Table 1. Abortion occurred between the fifth and eighth month of pregnancy. Occurrence of RFM was more frequent in cows that were seropositive. The period between abortion and first estrus was 79.06 v. 65.8 days for seropositive and seronegative groups, respectively, which differed significantly (P< 0.001). The results suggest that the higher occurrence of RFM after abortion in dairy NC-seropositive cows affects uterine involution, resulting in a delay of ovarian activity. Table 1.Neospora caninumseropositive and seronegative cows that aborted and their reproductive parameters.This study was supported by CNPq graduate funding. [ABSTRACT FROM AUTHOR]

Reproductive data from 304 cows were analyzed in milk herds of the western central region of the Rio Grande do Sul (RS), Brazil, to evaluate the effect of diseases in the postpartum period and their effect on the reproductive issues related to specialist (n= 180), semi-specialist (n= 84), and non-specialist (n= 40) systems of milk production. For statistical analysis ANOVA and correlation at 5% significance were used. The results revealed that 42% of females had postpartum disorders (129/304) and 58% were healthy (175/304). At 60 days after AI, 51% (114/225) of the cows were pregnant. Sick postpartum animals had a low rate of pregnancy (19%). In the specialized and non-specialized systems, a correlation (P= 0.00227; 0.0310) was detected between healthy animals and pregnant, among patients and non-pregnant (P= 0.0289; 0.0160), respectively. The incidence of uterine infection detected by ultrasound after parturition (28%) was higher than the incidence in animals with mastitis (16%). None of the production systems has proved to be an effective model to prevent postpartum disease. The incidence of disease postpartum, as well as the incidence of uterine infections, was similar between the systems of production. The neosporose, uterine infections and mastitis were the reproductive health problems most prevalent in the study. This study was support by CNPq graduate funding to the first and second authors. [ABSTRACT FROM AUTHOR]