Stephen W.J. Seager

Ovarian Response in the Estrual Cat Receiving Varying Dosages of HCG

Laparoscopy was utilized to determine the ovulatory response of the domestic cat to various dosages of human chorionic gonadotropin (HCG) administered intramuscularly at one or two time periods during estrus. A linear HCG dose-ovulatory response was observed in queens receiving 0--500 IU HCG as a single injection on day 1 or as injections given on days 1 and 2 of estrus. Animals treated with 500 IU HCG on day 1 or days 1 and 2 of estrus produced the maximum percent ovulation rates based on pre- and post-HCG ovarian morphology observation by laparoscopy (100.0, 95.9%, respectively). A single injection of 500 IU HCG produced a significant increase (p less than 0.05) in mean percent ovulation rate in comparison to the 0, 50 and 100 IU HCG single injections. Administration of 500 and 250 IU HCG for 2 days of estrus resulted in a greater percent ovulation rate than the 2-day injection of 50 IU (p less than 0.05). These results indicate that the proportion of mature follicles ovulating in an induced ovulator, such as the cat, is an increasing function of graded dosages of exogenous hormone.

Electroejaculation and semen analysis in a male lowland gorilla,Gorilla gorilla gorilla

Two electroejaculations and a testicular biopsy were performed on a lowland gorilla,Gorilla gorilla gorilla, to determine fertility. Sperm morphology showed 92.5% abnormal sperm which were of primary, or testicular, origin. Testicular biopsy revealed abnormally shaped nuclei in the later stages of spermiogenesis, supporting the semen analysis performed from the electroejaculations. The majority of abnormalities consisted of pyriform heads (23%) and abnormal acrosomes (35%).

Electroejaculation of paraplegic males followed by pregnancies**Supported by a grant from the Eastern Paralyzed Veterans of America.

Semen obtained by electroejaculation was used to achieve pregnancies in the spouses of T5-6 and T4-5 paraplegics. Viable semen was recovered in both an antegrade and retrograde fashion. In both cases, the SPA test was positive. Semen recovered for AIH IUI was washed and swum up prior to insemination.

Freeze Preservation of Squirrel Monkey Sperm for Use in Timed Fertilization Studies**Supported by a grant from the Ralston Purina Co., St. Louis, Mo. (to Dr. Seager); a grant to the Department of Cell Biology from the Ford Foundation; and National Institutes of Health Grant HD 7495-02.

These investigations were concerned with the response of squirrel monkey sperm to freezing. A procedure involving preincubation at 37 degrees C, progressive cooling combined with a two-step dilution, and freezing on Dry Ice was applied to semen samples collected by electroejaculation from two animals. Sperm concentrations in these samples were 321.8 X 10(6)/ml (+/-204.1 SD) and 532.8 X 10(6) ml (+/-117.1 SD), respectively. Sperm motility prior to freezing was 68.1% (+/- 15.9 SD) AND 63.6% (+/-14.8 SD). Following freezing and thawing, motilities of 53.8% (+/-17.1 SD) and 51.8% (+/-22.9 SD) were observed. The freezing procedure increased sperm motility in approximately 30% of samples from both animals. Changes in the motile behavior of sperm were not observed after freezing. Serum testosterone measurements, the first made in the squirrel monkey, gave values similar to those obtained for other primates. A progressive decline in testosterone concentration, seen in both animals during the course of these investigations, did not affect semen characteristics or the response of sperm to freezing.