PubMed Health⌕ Search

Biomedical subjects

A Okólski

Publications and source records attributed to A Okólski.

7 recordsLinked to original sources
PubMed1997

Equine oocyte-cumulus morphology as affected by follicular size.

From the ovaries of 256 slaughtered mares a total of 1713 follicles were isolated from which 1641 (95.8%) oocytes were recovered (6.4/mare). A total of 564 follicles and oocytes were evaluated for the degree of vascularisation of the follicle wall, the appearance of the follicular fluid and the location and morphology of the cumulus-oocyte-complex. Follicles with a diameter of >10 mm displayed more numerous, well branched and more pronounced blood vessels than the smaller ones (4-10 mm diameter) and most of them contained clear, yellowish fluid with few granulosa cells. The percentage of oocytes with compact cumuli increased significantly with an increasing diameter of the follicle, being 233%, 43.9%, 55.6% and 64.2% (P<0.01) for the follicles with diameters of 4-10, 11-15, 16-20 and 21-35 mm, respectively. The percentage of oocytes attached to the follicle wall also increased with increasing follicle size, being 48.0%, 59.6%, 81.5% and 90.1% (P<0.01), respectively. On the contrary, the percentage of oocytes floating in the follicular fluid decreased with increasing follicle diameter, from 52.0% in the smallest follicles to 9.9% in the biggest ones. A significantly greater percentage of oocytes found on the follicular wall than in the follicular fluid had a compact cumulus (56.6 versus 21.3%; P<0.01). For in vitro culture were accepted 30.4%, 54.3%, 60.7% and 77.8% (P<0.01) of oocytes from the follicles with diameters of 4-10, 11-15, 16-20 and 21-35 mm, respectively. After culture for 28-40 h in TCM 199 medium, 90 of a total of 165 (54.5%) oocytes reached the metaphase II stage of maturation.

Animals↗
PubMed1987

Evaluation of mare oocyte collection methods and stallion sperm penetration of zona-free hamster ova.

Comparisons were made between 2 methods of oocyte recovery from the ovarian follicles of slaughtered mares: 500 oocytes (3 per mare) were obtained by aspiration of follicular fluid from ovaries of 162 mares, and 120 oocytes (8 per mare) by isolation and rupture of follicles from ovaries of 14 mares. In the oocytes recovered after rupture of follicles, 89.2% were morphologically unchanged, in comparison to 29.3% obtained by aspiration of follicular fluid. Stallion spermatozoa capacitated in vitro were tested on zona-free hamster oocytes. The stallion spermatozoa were washed in TCM-199 and preincubated for 4-5 h at a concentration of 0.5-1.0 x 10(9)/ml. Of the 305 hamster oocytes fertilized by spermatozoa obtained from 8 stallions, 77.8% penetration was confirmed on the basis of the presence of enlarged heads of spermatozoa and male pronuclei with their corresponding tails. Spermatozoa from one of the stallions were tested 10 times, 8 months later. The percentage of penetrated oocytes averaged 52.8% (39.1-76.9%). In the control group of oocytes preincubated in the absence of spermatozoa, spontaneous activation and female pronuclei were found in 12 out of a total of 57.

Animals↗
PubMed1982

Prostaglandins in stallion semen.

The purpose of the experiment was to obtain preparatory information about the presence of prostaglandins in semen collected from various types of horses after different periods of sexual rest. Semen was collected with an artificial vagina. Prostaglandin-like activity was estimated by the bioassay procedure described by Vane (1). Results are expressed in ng/ml PGE(2) of seminal plasma. The total concentration of prostaglandins in the full ejaculate averaged 43.73 +/- 4.93 ng/ml of plasma while the total amount of prostaglandins in the ejaculate was 1076 ng. Taking into consideration the period of sexual rest in the stallion, statistically significant differences were found in the prostaglandin level in the semen of all the stallions.

Journal Article↗