本 硏究는 日本메추리의 成長過程中 細精管內 細胞組成의 變化樣相과 成熟時(14週齡時)細精管의 上皮週期 및 週期內 各期의 出現頻度를 觀察ㆍ究明코저 한 것이다. 育成中인 숫메추리 集團에서 2週부터 8週까지 每週齡과 14週齡에 各各 10首씩 無作爲 抽出해 諸般事項을 調査하였으며 얻어진 結果를 要約하면 다음과 같다.
1. 體重은 4週부터 5週齡사이, 精巢重量과 細精管의 管徑은 6週부터 8週齡사이에 急成長 하였다.
2. 胚芽細胞는 2~3週齡에 觀察되었고 4週齡 以後에는 出現되지 않았다. 精祖細胞는 Ⅰ型과 Ⅱ型 모두가 3週齡부터 出現되었고 精母細胞는 4週齡, 精子細胞는 6週齡以後에 出現되었다. 精子는 7週齡에 처음으로 觀察되었으나 完成된 精子의 射出은 8週齡부터였다.
3. 成熟時(14週齡時)의 精巢重量은 平均 3.7g이였고 體重에 대한 精巢重量比率은 約3%였다.
4. 成熟時 細精管의 管徑은 平均 192.08㎛였고 細精管 橫斷面上에 나타난 셀토리細胞, 精祖細胞, 第一精母細胞, 精子細胞 및 精子의 平均數는 各各 7.74, 40.81, 28.42, 104.55 및 169.98이였다. 精祖細胞는 두가지 型으로, 精子細胞는 세가지 型으로 各各 크게 分類되었다.
5. 成熟時의 細精管 上皮週期는 5期로 區分할 수 있었고 各期의 特徵은 다음과 같았다.
第一期 : 精子細胞 Ⅰ型과 Ⅱ型이 出現된 時期
第二期 : Ⅲ型의 精子細胞 出現時期
第三期 : Ⅲ型의 精子細胞가 未成熟 精子로 되어 基底膜쪽으로 移動해 셀토리細胞의 細胞質에 모여드는 時期
第四期 : 셀토리細胞의 細胞質內에 15~20個의 精子가 하나의 結束을 이룸.
第五期 : 結束된 精子群이 內腔쪽으로 移動하여 사라질때 까지임.
6. 細精管의 橫斷面上에는 上反週期內 2~3個의 期가 同時에 觀察되었으며 各期의 出現頻度는 一期에서 五期까지 各各 11.97%, 23.05%, 27.96%, 19.04% 및 17.98%였다.
以上과 같은 結果들로 보아 일본메추리의 여름철 性成熟은 8週齡부터 이며 細精管의 上皮週期는 哺乳動物들과는 달리 五期로 區分되는 特徵을 갖는다고 할 수 있다.
This study was conducted to observe 1) the changes of cellular association in seminiferous tubles from 2 to 8 weeks of age, and 2) the cycle phenomena of seminiferous epithelia at 14 weeks of age in Japanese quail. Total 80 birds were examined at a week interval from 2 to 8 weeks, and 14 weeks of age. The results were summarized as follows;
1) The body and testis weights showed most prominent increase during 4 to 5 weeks and 6 to 8 weeks of age respectively. And also the diameters of seminiferous tubles were abruptly enlaged during 6 to 8 weeks of age.
2) Genocytes in the seminiferous tubles were still in existence at 3 weeks of age, however they did not come out after 4 weeks of age. Spermatogonia, primary spermatocytes and spermatids made their first appearances in the seminiferous from 3, 4 and 6 weeks of age, respectively. Spermatozoa were observed for the first time at 7 weeks of age, but full spermatogenic activity was completed from 8 weeks of age.
3) At 14 weeks of age, the average weight at testis was 3.7g and its ratio to the body weight was approximately 3.0 percent. And at this age, average diameter of seminiferous tubules was 192.08㎛, and average numbers of spermatogonia, spermatocytes, spermatids and spermatozoa within the cross section of seminiferous tubules were 7.74, 40.81, 28.42, 104.55 and 105.98, respectively. Spermatogonia and spermatid were classfied into 2 and 3 types, respectively.
4) At 14 weeks of age, the cycle of seminiferous epithelium could be divided into 5 stages with following characterisitics.
(1) Stage Ⅰ : Seminiferous tubules showing type Ⅰ and Ⅱ spermatids.
(2) Stage Ⅱ : Seminiferous tubules showing type Ⅲ spermatids only.
(3) Stage Ⅲ : Immature spermatozoa gathered near the sertoli cytoplasm.
(4) Stage Ⅳ : Forming a bundle of 15-20 spematozoa.
(5) Stage Ⅴ : Spermatozoa bundle leaving the sertoli cytoplasm into lumen of the seminiferous tubule.
5) Usually 2-3 stages of the seminiferous epithelium cycle were concurrently appeared within a tubular cross section, and frequency of each stage from Ⅰ to Ⅴ within cross section of seminiferous tubules were 11.97%, 27.03%, 27.96%, 19.04% and 17.98%, respectively.