Ovarian and Uterine Morphology and Function in Angus and Brahman Cows3

Abstract

Ovarian characteristics, daily serum progesterone (P4) and estradiol-17 beta (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 less than .001) and follicular fluid (P less than .01) weights, stromal weight (P less than .01) and number of follicles less than 5 mm in diameter (P less than .01) for both ovaries combined were greater in Brahman than Angus cows. Corpus luteum weight (P less than .001), luteal P4 content (P less than .08) and number of follicles greater than 5 mm in diameter for both ovaries combined (P less than .05) were greater for Angus than for Brahman cows. Overall, mean serum P4 concentrations were greater in nonpregnant (P less than .05), pregnant (P less than .005) and combined (P less than .025) reproductive categories for Angus than corresponding categories of Brahman cows and mean serum E2 concentrations were greater in remnant (P less than .025) and combined (P less than .05) reproductive categories for Angus than corresponding categories of Brahman cows. Mean total uterine luminal protein was greater (P less than .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, X 10(-3)) of 9, 15.5, 34.2, 41.3, 46.2 and 183.1 were greater (P less than .05 to P less than .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 less than .05 to P less than .001) in pregnant and combined reproductive categories for Angus than for Brahman cows.

Endocrine and metabolic differences between Bos taurus and Bos indicus cows andimplications for reproductive management

“…In studies with Nelore cattle, the diameter of ovulatory follicle was between 11 and 14 mm (Figueiredo et al, 1997;Sartorelli et al, 2005;Sartori et al, 2016), and the maximum diameter of the ovulatory follicle in Holstein cattle was between 13 and 19 mm (Ginther et al, 1989;Sartori et al, 2002aSartori et al, , 2004. Similarly, the CL diameter of B. indicus ranged from 17 to 21 mm or ~2.5 to 5.0 cm 3 (Segerson et al, 1984;Rhodes et al, 1995;Figueiredo et al, 1997;Bó et al, 2003;Sartori et al, 2016), whereas the CL diameter of B. taurus ranged from 20 and 30 mm or ~4.0 to 14.0 cm 3 (Ginther et al, 1989;Bó et al, 2003;Sartori et al, 2004Sartori et al, , 2016.…”

Estádios de desenvolvimento embrionário de vacas zebuínas superovuladas

“…O peso do CL está relacionado com sua capacidade de produzir progesterona, hormônio intimamente relacionado com a manutenção de um ambiente útero-tubárico adequado ao desenvolvimento embrionário e manutenção do próprio CL durante o período crítico da vida embrionária (da ovulação à implantação), quando ocorre o reconhecimento materno da gestação (Fields & Fields, 1996). Fêmeas zebuínas apresentaram CL menor, com menor conteúdo de progesterona por grama de tecido luteal (Segerson et al, 1984). Neste aspecto, estudos anteriores reportaram que a detecção do CL por palpação transretal é mais difícil em zebuínos do que em taurinos (Plasse et al, 1968a;Vale Filho et al, 1986).…”

Efficacy of Hormonal (PGF and eCG) Treatment on the Reproductive Performance of Muturu Cows Crossed with White Fulani Semen under Natural Grazing Condition: A Research Work

“…It goes without saying that follicle sizes could be categorized into 3 classes as depicted in Table 1. Several studies have also characterized follicular -wave dynamics in Bos indicus cattle and indicated that Bos indicus cattle have smaller diameters of the dominant follicles and corpus luteums (B.O et al, 2003) and lower serum progesterone concentrations (Segerson et al, 1984) relative to those of Bos Taurus Cattle. Previous studies also showed that the diameter of the dominant follicle at the time of deviation has been reported to be smaller in Nelore (6.0 to 6.3mm) Sartorelli et al, (2005) than in Holstein (8.5m) cattle (Ginther et al, 1996).…”