| Abstrakt: |
Ovarian characteristics, daily serum progesterone (P4) and estradiol-17β(E2) concentrations (d 7 through 17) and uterine luminal secretory protein components and histological variables were evaluated in parous Bos taurus (Angus, n=20) and Bos indicus (Brahman, n=19) cows. Cows were slaughtered on d 17 (estrus = d 0) for measurement of ovarian structures, flushing of uteri and removal of uterine tissue for histological evaluation. Cows were placed into one of three reproductive categories: nonpregnant, remnant (flushings contained remnants of embryonic tissue) or pregnant. For ovarian and uterine variables, there were only a few differences among reproductive categories within breeds. For combined categories, weight of the active ovary (containing the corpus luteum) was similar between breeds, but inactive ovarian (P<.001) and follicular fluid (P<.01) weights, stromal weight (P<.01) and number of follicles <5 mm in diameter (P<.01) for both ovaries combined were greater in Brahman than Angus cows. Corpus luteum weight (P<.001), luteal P4content (P<.08) and number of follicles >5 mm in diameter for both ovaries combined (P<.05) were greater for Angus than for Brahman cows. Overall, mean serum P4concentrations were greater in nonpregnant (P<.05), pregnant (P<.005) and combined (P<.025) reproductive categories for Angus than corresponding categories of Brahman cows and mean serum E2concentrations were greater in remnant (P<.025) and combined (P<.05) reproductive categories for Angus than corresponding categories of Brahman cows. Mean total uterine luminal protein was greater (P<.05) in Angus than in Brahman cows for pregnant (23.4 vs 14.7 mg, respectively) and combined reproductive categories (22.4 vs 16.1 mg, respectively). Using electrophoretic analyses, percentage composition of three uterine specific cathode migrating protein bands and quantitative estimates of proteins with molecular weights (MW, × 10−3) of 9, 15.5, 34.2, 41.3, 46.2 and 183.1 were greater (P<.05 to P<.001) in uterine flushings from Angus than from Brahman cows. Uterine, myometrial and endometrial thicknesses, number of glands/microscopic field and uterine luminal epithelial cell height variables were generally greater (P<.05 to P<.001) in pregnant and combined reproductive categories for Angus than for Brahman cows. |
