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21.
In the mare, natural breeding is associated with bacterial contamination of the reproductive tract. The purpose of this study was to examine postcoital bacterial contamination and the resulting inflammatory response of the uterus. Uterine swabs for bacteriological and cytological examination were obtained from 80 mares. Each mare was sampled once between 4 and 69 hours postbreeding. In mares which did not conceive, sampling was repeated at the following estrus. The findings were compared with those obtained prior to breeding and correlated with the breeding outcome. Bacteria were cultured from 72.5% of the postcoital swabs. There was a wide spectrum of organisms which included species known as potential causes of endometritis. Neutrophilic granulocytes were found in varying concentrations in 48.8% of cases. In 16.3% of mares both bacteriological and cytological examinations were negative. Mares with positive bacteriological and/or cytological results at the postcoital examination had better foaling rates compared to the remaining mares (p less than 0.05). The postcoital findings did not correlate with those of the prebreeding examination, or with the interval between breeding and sampling, or with the different stallions.  相似文献   
22.
A three‐year‐old intact female Old English sheepdog was presented for evaluation of infertility. A uterine biopsy was performed during dioestrus, and the microscopic appearance was inconsistent with progesterone stimulation; the glands were sparse, simple and failed to show coiling, while the glandular epithelium was cuboidal instead of columnar. There was very little evidence of glandular activity. Due to the inappropriate appearance of the glands for the stage of the cycle, immunohistochemistry for progesterone receptors was performed. No progesterone receptor‐positive immunoreactivity was identified in the endometrial luminal epithelium, glandular epithelium or stroma. Weak intranuclear immunoreactivity was identified within the smooth muscle cells of the myometrium. The absence of progesterone receptors within the endometrial glands is the most likely explanation for the abnormal appearance of the endometrium and for this bitch's infertility. To our knowledge, this is the first report of endometrial progesterone receptor absence in a bitch.  相似文献   
23.
To investigate the vulvovestibular contamination of endometrial culture swabs in the mare, a liquid culture of a streptomycin-resistant strain of Escherichia coli was applied to the vulvovestibular area of mares and used as a marker of contamination of endometrial culture swabs. Prior to taking endometrial swabs, the perineal area was washed with soap, rinsed with water, and dried. Endometrial culture swabs were taken from mares that were in anestrus or diestrus and from mares that were in estrus. When a manual transvaginal swabbing technique was used, 22 of 24 endometrial swab specimens from 12 mares were contaminated with the experimental bacterial strain; culture of only one endometrial swab yielded more than nine colonies. When a speculum approach was employed, three of 12 swab specimens from 12 mares yielded between one and three colonies. The stage of cycle had no effect on the extent of contamination, but the proportion of positive cultures was significantly smaller when swabs were taken via a vaginal speculum approach, compared to a manual transvaginal approach. Complete preclusion of vulvovestibular contamination of endometrial swab specimens was not achieved; however, fewer than ten colonies can be expected even in mares in which the vulvovestibular area has been thoroughly contaminated with a broth culture, provided that the perineal area is adequately cleaned prior to swabbing.  相似文献   
24.
Endometrial sections from mares with varying degrees of mononuclear cell infiltration were examined for immunoglobulin (Ig)A-, IgM-, IgG(T)- and IgG(Fc)-containing cells, luminal and glandular epithelial cell Ig-staining and free interstitial Ig-staining, using a peroxidase anti-peroxidase technique. Mares with mild to moderate (Group 2) and mares with severe diffuse mononuclear cell infiltration, superimposed by acute endometritis (Group 3), had significantly higher numbers of Ig-containing cells than genitally-normal mares (Group 1). The differences between Groups 1 and 3 were significant for all four isotypes. In Groups 1 and 2, numbers of IgA-containing cells were significantly larger than numbers of IgM- and IgG(T)-containing cells. Generally, more glandular epithelial cells stained for IgA and IgM than for IgG(T) and IgG(Fc), and Ig-staining for all isotypes increased from Group 1 to Group 3. Free interstitial staining did not appear to differ among the three groups, but IgG(Fc)- and IgG(T)-staining generally was more intense than IgA- and IgM-staining. The efficiency of uterine defence in the mare does not seem to depend solely on humoral factors, and defects involving other components of the defence system may contribute to failure of the uterus to clear infection.  相似文献   
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A feeding‐and‐digestibility trials were carried out to evaluate the efficacy of replacing fishmeal with brewers yeast Saccharomyces cerevisiae in diets of pacu, Piaractus mesopotamicus, juveniles. The feeding trial was conducted during 54 days with 450 fish (26.6 ± 1.7 g) testing six isonitrogenous (270 g kg?1 crude protein) and isoenergetic (19 MJ kg?1 crude energy) diets, with increasing yeast level to replace 0 (control), 30, 35, 50, 70 or 100% of dietary fishmeal. Growth performance and feed utilization increased with increasing dietary yeast level until 50% fishmeal replacement. Protein retention efficiency was higher in fish fed 35 and 50%. Protein digestibility and the fillet hue (the red/green chromaticity) were not significantly different among all treatments. Nitrogen gains were significantly improved in fish fed 35% replacement diet compared to fish fed the control diet. The retentions of indispensable amino acids tended to increase with increasing dietary yeast levels, with maximum retention at 35–50%. On the basis of our results, replacing 50% fishmeal by yeast in pacu diets successfully improved feed efficiency and growth performance, and reduced nitrogen losses, thereby reducing the nitrogen outputs from fish farms.  相似文献   
28.
The objective of this study is to evaluate the reproductive efficiency in donors and recipient Mangalarga Marchador mares in commercial programmes of embryo transfer (ET) and the effects of some reproductive characteristics and ET methodology on conception rates in the recipient mares. A total of 1140 flushing procedures were performed and 830 embryos (72.8%) were recovered. There were no differences between the rates of embryonic recovery in the different breeding seasons (p > 0.05) and 92.8% of the recovered embryos were 8–9 days old. There was no difference in the embryonic recovery regarding the collection order from the first to the ninth embryo collection along the breeding season, as well as among mares inseminated during the foal heat or subsequent cycles (p > 0.05). Pregnancy rates observed in the total period of all reproductive seasons at 15, 30, 45 and 60 days of pregnancy were 73.4, 69.9, 66.7 and 64.5%, respectively. Differences in pregnancy rate and early embryonic loss rates were not observed between embryos transferred immediately after collection (66.8% and 13.5%) and embryos transported at room temperature for periods of <1 h (62.9% and 14.4%; p > 0.05). Pregnancy rates were higher when the interval between ovulations of donor and recipient mares remained between ?3 and ?2 days (p < 0.05), and the lowest rates were observed for intervals of ?6 days (p < 0.05) with intermediary values for intervals of ?1, 0 and +1 (p > 0.05). Embryonic loss rates, however, did not differ between intervals of ovulation’s synchronism between donor and recipient mares (p > 0.05). This flexibilization in the ovulatory synchronism between donor and recipient mares optimizes the use of recipient mares, thus reducing costs and facilitating management of horse breeding farms.  相似文献   
29.
Clinical and subclinical endometritis are common causes of infertility and subfertility in high producing dairy cattle, delaying the onset of ovarian cyclic activity after parturition, extending luteal phases and reducing conception rates. Escherichia coli and Arcanobacterium pyogenes cause endometrial damage and inflammation. Components of microbes, such as lipopolysaccharide (LPS), are detected by Toll-like receptors on endometrial cells, leading to secretion of cytokines, chemokines and antimicrobial peptides. Long luteal phases associated with endometritis are probably caused by a switch in endometrial prostaglandin production from prostaglandin F2a (PGF) to prostaglandin E2. In addition, LPS impairs the function of the hypothalamus and pituitary, and directly perturbs ovarian granulosa cells steroidogenesis, providing mechanisms to explain the association between uterine disease and anovulatory anoestrus. Cows with uterine disease that ovulate have lower peripheral plasma progesterone concentrations that may further reduce the chance of conception associated with endometritis.  相似文献   
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