梅山豚とランドレ-スの1代雑種における卵巣,卵管および子宮角の発達

概要

論文の詳細を見る
Ovaries, oviducts and uterine horns collected from a total of seventeen Meishan×Landrace gilts of various ages were examined histologically. Vesicular follicles were already observed in ovaries at 45 days of age. Subsequently the ovarian weight increased rapidly up to 75 days of age, as the increase of protruding vesicular follicles. Between 75 and 105 days of age, the number of protruding follicles did not change significantly. One gilt at 120 days and all at 135 days of age had ovaries with corpora lutea. The weights of the oviducts and the uterine horns increased rapidly from 45 days and from 60 days of age, respectively. Thickness of the inner circular and outer longitudinal layers of the myometrium also increased rapidly from 45 days of age. After the onset of estrous cycles, the weight of the uterine horns increased markedly. These results show that 1) the ovaries of Meishan×Landrace gilts develop rapidly from 45 days of age, which development is accompanied by the increase of the weight of the oviducts and uterine horns; and 2) the gilts start estrous cycles between 120 and 135 days of age.
社団法人日本畜産学会の論文