Jiménez R, Alarcón F J, Sánchez A, Burgos M, De La Guardia R D
Departmento de Genética, Universidad de Granada, Spain.
J Exp Zool. 1996 Feb 1;274(2):130-7. doi: 10.1002/(SICI)1097-010X(19960201)274:2<130::AID-JEZ6>3.0.CO;2-Q.
The age-related evolution and ontogenic origin of the ovotestes in fertile females of the Spanish mole (Talpa occidentalis) were studied. Volume of the ovotestis and its ovarian and testicular components, size of the epididymis and testicular cords, number of ovarian follicles and testicular cords, uterus weight, and age index were analyzed statistically in a large sample of young and adult individuals of this species. Comparison of means and linear correlation analyses were done. Most variables were shown to be age dependent, with a period of rapid change during puberty. In adult animals, volume of the ovarian portion and uterus weight followed a seasonal cycle of sexual activity. Interindividual variability was evident in most of the variables investigated except for the number of testicular cords per ovotestis, which remained unchanged throughout the animal's life and hence was not inversely correlated with the number of ovarian follicles. This finding ruled out an ovary-testis transdifferentiation hypothesis for the ontogenic origin of the testicular tissue in the ovotestes of female moles. An alternative hypothesis based in the absence of oocytes in a portion of the undifferentiated fetal gonad is proposed in accordance with a new general model for mammalian sex determination.
对西班牙鼹鼠（Talpa occidentalis）可育雌性个体中卵睾体的年龄相关演变和个体发生起源进行了研究。在该物种的大量幼年和成年个体样本中，对卵睾体及其卵巢和睾丸成分的体积、附睾和睾丸索的大小、卵巢卵泡和睾丸索的数量、子宫重量以及年龄指数进行了统计分析。进行了均值比较和线性相关分析。大多数变量显示出与年龄相关，在青春期有一个快速变化期。在成年动物中，卵巢部分的体积和子宫重量遵循性活动的季节性周期。除了每个卵睾体的睾丸索数量在动物一生中保持不变且因此与卵巢卵泡数量无负相关外，在所研究的大多数变量中个体间差异明显。这一发现排除了雌性鼹鼠卵睾体中睾丸组织个体发生起源的卵巢 - 睾丸转分化假说。根据哺乳动物性别决定的新通用模型，提出了一种基于未分化胎儿性腺一部分中不存在卵母细胞的替代假说。
