Efficacy of difloxacin for the control of postpartum uterine infections of ewes

Clinical, Ultrasonographic, Bacteriological, Cytological and Histopathological Findings of Uterine Involution in Ewes with Uterine Infection

The objectives of the study were (a) to study the characteristics of uterine involution in ewes that had developed subclinical uterine infection in the immediately post-partum period and (b) to evaluate effects of the infection in the subsequent reproductive performance of ewes. Uterine infection was induced in ewes (I, n = 10) by intrauterine inoculation of Escherichia coli; uninoculated controls were included (C, n = 12). Animals were examined at regular intervals before and post-inoculation. Clinical and ultrasonographic examinations were performed. Vaginal swab samples and biopsy uterine tissue samples were collected for bacteriological, cytological and histological examination. Finally, ewes were put to rams and reproductive performance was monitored. After challenge, it was ultrasonographically found that caruncular dimensions, myometrial thickness and diameter of uterine lumen were greater in I ewes. In these ewes, particular reduction of dimensions occurred during the second week post-partum, whilst in C ewes during the first week. The uterine artery diameter and the blood flow into the uterus were also greater in I than in C ewes. E. coli infection was more frequent and of longer duration in I than in C ewes: in 68.1% and 50.0% of ewes and 19.5 and 14 days, respectively. There was lower proportion of neutrophils and higher of lymphocytes in group I than in C. In inoculated ewes, there was histological evidence of uterine epithelial destruction, increased cellular infiltration, hyperaemia and extracasation, which persisted up to 42 days post-partum. During the subsequent reproductive season, all ewes in group I lambed normally and produced healthy and viable lambs. No significant difference in reproductive performance parameters were seen in I comparison to C ewes. It is concluded that the innate immunity of the uterus sufficed to counteract the bacterial infection, although the process of involution took longer than in healthy animals; moreover, the ultrasonographic examination is a useful means for assessment of the genital tract of ewes post-partum; finally, no adverse effects were noted in the subsequent reproductive performance of ewes.

Trematode infections in pregnant ewes can predispose to mastitis during the subsequent lactation period

Objective was to investigate if trematode infections predispose ewes to mastitis and/or metritis. We used 80 trematode-infected ewes: primigravidae in group P-A and multigravidae in M-A remained untreated, primigravidae in P-B and multigravidae in M-B were drenched with netobimin and multigravidae in M-C were given rafoxanide. We collected faecal samples for parasitological examination, blood samples for β-hydroxybutyrate concentration measurement and uterine content, teat duct material and milk samples for bacteriological examination. We found significant differences in blood β-hydroxybutyrate concentrations between M-A, M-B and M-C during pregnancy (P ⩽ 0.002). We did not observe significant differences between groups regarding development of metritis (P>0.83). We found that for M-A, M-B and M-C ewes, respectively, median time to first case of mastitis was 5.75, 21 and 6.75 days after lambing (P = 0.003) and incidence risk of mastitis was 0.308, 0.069 and 0.222 (P = 0.047). We postulate that trematode infections predispose ewes to mastitis; perhaps, increased β-hydroxybutyrate blood concentrations adversely affect mammary cellular defences. This is the first report associating parasitic infections with mastitis in sheep.