Studies on testses development and spermatogenesis in dog |
Jae-hong Lee1, Young-seok Park1, Seong-ho Lee2 |
1Department of Veterinary Medicine, College of Veterinary Medicine, Chonnam National University 2Gong-Joo National Junior College |
개의 정소발육과 정자발생에 관한 연구 |
이재홍1, 박영석1, 이성호2 |
1전남대학교 수의과대학 수의학과 2공주전문대학 |
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Abstract |
This study was conducted in order to observe the changes in cellular association of seminiferous tubules from 16 to 24 weeks of age and to obtain the cycle and relative duration of the seminiferous epithelia from 28 to 44 weeks of age in Korean native dogs. The results were summarized as follows; 1. Gonocytes were seen at 16 weeks of age, however they were not observed as from 20 weeks of age. Both type A and type B-spermatogonia occurred from 20 weeks, while primary spermatocytes were found from 20 weeks. Secondary spermatocytes and spermatids appeared from 28 weeks. Spermatozoa were observed at first at 28 weeks of age. 2. Type A-spermatogonia appeared approximately 1.6 times as many at stage II compared to stage I, while the same numbers of cells were seen in both stage I and VII, showing the least number among VIII stages of the cycle of the seminiferous epithelia. The type B-spermatogonia were found from stage VI to VIII, Leptotene phase of the primary spermatocyte divided from type B-spermatogonia in stage VII observed at the stage VIII. Pachytene phase of the primary spermatocytes were shown the least in number at stage IV. The secondary spermatocyte could be seen only at stage IV. 3. The relative frequency of each stage from stage I to VIII of the cycle of the seminiferous epithelia was 30.3, 12.0, 9.8, 4.2, 8.5, 10.5, 11.4 and 13.4% respectively. Thus the establishment of spermatogenesis in Korean native dog was completed from 28 weeks of age. |
Key Words:
Spermatogenesis, dog, cycle of the seminiferous tubule, relative frequency |
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