Almeida-Santos Selma M, Laporta-Ferreira Iara L, Antoniazzi Marta M, Jared Carlos
Laboratory of Herpetology, Instituto Butantan, Av. Dr Vital Brazil 1500, CEP 05503-900, São Paulo, Brazil.
Comp Biochem Physiol A Mol Integr Physiol. 2004 Oct;139(2):169-74. doi: 10.1016/j.cbpb.2004.08.004.
Seasonal variations in spermatozoa numbers and in sperm motility along the vas deferens in Crotalus durissus terrificus from southeastern Brazil were analyzed. Our data demonstrate storage and motility of the spermatozoa along the vas deferens throughout the year. This is characteristic of a postnuptial reproductive cycle, usually found in snakes living in temperate climates. We describe similarities in reproductive cycle patterns found in the tropical nonhibernator C. durissus terrificus and in hibernator snakes from temperate zones. Our results show that in C. durissus terrificus, a significant difference in spermatozoa counts occurs between winter and summer. Higher numbers of spermatozoa in summer and autumn, due to intense spermiogenesis, coincides with the mating season in autumn. These data indicate that after spermiogenesis in summer, the males combine the peak of sperm storage to the period females are attractive. Mating, however, is not linked to ovulation, and the sperm is stored in the females during winter until fertilization occurs in spring. In the males, after mating, spermatozoon counts low. In spring, they gradually increase, turning again the highest in summer and autumn. During spermiogenesis in the convoluted vas deferens, spermatozoa gain motility, enhancing their performance along their way towards the distal portion.
分析了巴西东南部杜氏响尾蛇（Crotalus durissus terrificus）输精管中精子数量和精子活力的季节性变化。我们的数据表明，全年输精管中都存在精子的储存和活力。这是婚后生殖周期的特征，通常见于生活在温带气候的蛇类。我们描述了热带非冬眠的杜氏响尾蛇与温带冬眠蛇类在生殖周期模式上的相似之处。我们的结果表明，在杜氏响尾蛇中，冬季和夏季的精子数量存在显著差异。由于强烈的精子发生作用，夏季和秋季的精子数量较多，这与秋季的交配季节相吻合。这些数据表明，夏季精子发生后，雄性将精子储存的高峰期与雌性具有吸引力的时期相结合。然而，交配与排卵无关，精子在雌性体内储存至冬季，直到春季发生受精。在雄性中，交配后精子数量减少。在春季，精子数量逐渐增加，在夏季和秋季再次达到最高水平。在输精管的卷曲部分进行精子发生过程中，精子获得活力，在向远端移动的过程中增强其性能。
