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S W Seager

Publications and source records attributed to S W Seager.

47 records · Page 3Linked to original sources

Laparoscopic exposure and sequential observation of the ovary of the cycling bitch.

A method was developed to alter surgically the bursa of the bitch to allow sequential observation of the ovary by means of laparoscopy. Adult anesthetized female dogs of three breeds underwent laparoscopic examinations in which each natural bursa slit was lengthened 1.0-1.5 cm using laparoscopic hook scissors in conjunction with electrocautery. The ovary could be effectively and repeatedly exposed for laparoscopic viewing through the lengthened bursa slit. Neither laparoscopic surgery nor frequent routine laparoscopic examinations of the reproductive organs had an effect on subsequent ovarian activity. All dogs subjected to the laparoscopic ovarian exposure technique exhibited estrus behavior, follicle development, ovulation and corpus luteum formation. Preovulatory follicular development was detected as early as 11 days before ovulation with the most rapid follicular maturation occurring two to three days before ovulation. Follicular collapse and extensive hemorrhage at the rupture site during ovulation did not occur. Release of the cumulus mass from a vesicular follicle was observed in one bitch. The cumulative mass adhered to the follicular wall for an indefinite time following ovulation. The structural size of the bitch corpus luteum was maximal four to eight days following ovulation. Corpora lutea remained visible on the ovarian surface for 16 weeks. No differences in cyclic ovarian morphology were observed among the three breeds of dogs studied.

Animals↗

Successful pregnancies with concentrated frozen canine semen.

A method for concentrating canine semen prior to freezing was developed. Concentration was by centrifugation at 1470 g at room temperature, after which the majority of seminal fluid was removed. Motility, speed of progression, and morphology of sperm were not affected by concentration. Subsequent artificial insemination using concentrated semen resulted in a conception rate of 92%. The offspring were normal and healthy. The mean litter size (6.7) and birth weight (256.3 g) were comparable to those reported by a commercial supplier (6.2 and 255.7 g) of the same breed (beagle).

Animals↗

Freeze preservation of squirrel monkey sperm for use in timed fertilization studies.

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.

Animals↗