نوع مقاله : تغذیه
1 گروه شیلات، دانشکده شیلات و محیط زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
2 موسسه تحقیقات بین المللی ماهیان خاویاری دادمان ، سازمان تحقیقات شیلات ایران ، رشت ، ایران
3 دانشگاه آزاداسلامی واحد علوم و تحقیقات تهران, گروه علوم دامی, ایران
عنوان مقاله [English]
The present research was carried out in order to examination of the effects of astaxanthine and β-carotene supplementation on reproductive indices and the tensions induced by high density in the early development stage of goldfish embryos (Carassius auratus). The study was included seven treatments based six diets containing astaxanthine (A) and β-carotene (B) with three different levels of 50, 100, and 150 mg kg-1 of the diet, as well as a control diet which was devoid of any added carotenoid. The fish were fed using these diets for a period of 4 months. At the end of the experiment, the female fish were artificially bred with identical male fish (which were fed with the control diet). The various propagation indices in different treatments were compared. In the incubation phase, the fertilized eggs were incubated in batches containing 10000 eggs and 20000 eggs per liter. The result showed a significantly difference for egg fertilization rate betweendifferent treatments (P≤0.05). The egg survivability rate from fertilization up to the onset of gastrolasion stage turned out to be significantly different between treatments with normal density and treatment with double density (P≤0.05). In this stage, the egg survivability rate in the normal density treatment had higher than those treatments which had two times greater density than the normal one. In the egg development stage, and in the normal density treatments, the astaxanthine percentage out of the total carotenoid showed significant different rather than double density treatments.