Seasonal Changes in Ovarian Follicle Growth in Iran Viper (Vipera albicornuta)

Abstract

The Vipera albicornuta is an economically important snake of Iran, its venom is used for antivenin production, and we need to breed the snake in the captivity. In order to know about the viper's reproductive biology, seasonal alterations in ovarian weight, morphology, and the follicles developmental stages in Vipera albicornuta were studied using macroscopic parameters and histological examination of reproductive tissues during a year. Twenty-four female vipers were collected from mountainous zone of Bostanabad, East Azerbaijan, and Tarom in Zanjan through years 2011-2012. Evaluation of the reproductive parameters of this viper is performed for the first time in Iran. Our observation revealed that vitellogenesis cycle begins in autumn and continues till early summer; ovaries and follicles are in previtellogenesis stage in autumn and vitellogenesis in winter and during spring. Weight of ovary is heaviest in spring, ovulation occurs in late spring till early summer, and copulation is prior to ovulation.

Serum Level of Thyroid Stimulating Hormone, Triiodothyronine, Thyroxin and Weight Rate in Caucasian Pit Viper (Viperidae: Gloydius Halys Caucasicus) of Iran during Different Seasons

“…The relationship between body condition and reproductive activity is wellestablished in snakes; however, little is known about the thyroid hormonal regulating this relationship in snakes. At the present study, body weight of female Caucasian viper (C. viper) in summer was more than autumn and winter (P≤ 0.05) that may be because of snake activity in suitable temperature [37] and food availability [34] in summer that is similar to body fat increment in viviparous vipers according to Afsharzadeh, et al [38], following mating, the body weight of snake have decreased in autumn. Our previous studies have shown male C. vipers have summer/ aestival spermatogenesis [37] and mating with female may occur at the time of ovulation in summer [39,40].…”

The reproductive cycle of the flowered racer (Platyceps florulentus) from a rural area to the east of the Nile Delta, Egypt.

“…The timing of the different stages of the reproductive cycle of males of the present study could generally be compared with that for other snake species of the Middle East such as the grass snake, Natrix natrix (Faghiri et al, 2011) and the dice snake, Natrix tessellata (Savasari et al, 2015) in northern Iran. The reproductive cycle of females could also be compared with that of other serpents of the region such as the Iran viper, Vipera albicornuta (Afsharzadeh et al, 2015). Synchronization between the reproductive activities of both males and females of the Schokari sand racer, Psammophis schokari, in Israel was recorded in spring (Goldberg, 2015).…”

“…The male reproductive cycle of P. florulentus could thus be referred to as a vernal cycle (Savasari et al, 2015). Ovulation in females of this species follows the peak of spermatogenesis in males so that, the female reproductive cycle could be referred to as a prenuptial cycle (Afsharzadeh et al, 2015).…”