Induced reproduction of aphanius fasciatus by ecophysiological conditioning and hormonal treatment in fresh and marine water

The reproductive performance of a stock of 234 Mediterranean toothcarp (Aphanius fasciatus) was investigated. Spawning was induced using ecophysiological conditioning where water temperature and photoperiod were changed in fresh and marine water. A fish group maintained in marine water was hormonally treated with carp pituitary extract (CPE). The combined effect of temperature, photoperiod and hormonal treatment induced ovary maturation and larvae production in all experimental groups. Reproductive rate was always very high with respect to natural reproduction (average eggs/female: 2-4), the final average number of eggs/female ranging from 5.9 to 10.5. Additionally, a 97-100% hatching rate was obtained. The results of this study show that Mediterranean toothcarp reproductive condition may be controlled in an artificial environment: the lack of mortality in adults during freshwater and marine water acclimation and during conditioning indicates a good domestication and plasticity in the reproductive parameters. The results presented here are an important contribution in the pursuit of the propagation of the Mediterranean toothcarp for the biological control of mosquito larvae.