Intercorrência entre a mastite e falhas no desempenho reprodutivo de ovelhas Lacaune

Abstract

The objective of this study was to evaluate the effect of the occurrence and etiology of subclinical mastitis (SM) on uterine involution (UI), return to estrus and postpartum ovarian characteristics. Dairy sheep (n = 87) were categorized based on the occurrence of one or more SM events according to evaluation 5, 20, 35 and 50 after calving. Animals with MS (n = 49) had the infection categorized according to etiology into four groups (coagulase negative Staphylococcus, Staphylococcus aureus, Coliform and other Gram-positive Pathogens). California Mastitis Test positive animals and pathogen isolation negative animals were identified as uninsulated (SI). The control group (n = 38) consisted of sheep that did not have SM in any of the evaluations. The occurrence and etiology of SM were not associated with macroscopic UI, and at 45 days of lactation all sheep had reached UI (uterine horn diameter ≤ 2 cm). The detection of estrus began on the 20th day after calving and until the 60th day 57.47% (50/87) of the sheep manifested estrus. The probability of estrus occurrence within 30, 45 and 60 days after calving was evaluated. The occurrence of SM on days 5, 20, 35 and 50 after calving did not interfere (P> 0.05) in the probability of estrus manifestation (P> 0.05). The number of follicles in classes 3 to 5 mm,> 5 mm, number of luteal bodies, total luteal area and diameter of the two largest follicles were not affected (P> 0.05) by SM on days 5, 20 and 35 after calving . The occurrence and etiology of SM on day 50 were related to the diameter of largest follicle (P = 0.04), The control group and the SM group detected by the CNS had the largest diameter than the SI group. In conclusion, the smaller diameter of the largest follicle in MS may indicate that immune / inflammatory challenge can disrupt follicular growth without interfering with UI and return to postpartum ovarian cyclicity.