The Persian sturgeon (Acipenser persicus) is considered as an endemic sturgeon of the south part of the Caspian Sea and provides the highest Iranian caviar production. Due to overfishing, degradation of the rivers conditions of the natural reproductive habitats, the fish stocks is decreasing. The immature breeders do not response to hormonal therapy at the sturgeon hatcheries as most having PI (above 10) and large numbers of breeders caught and transported to the hatcheries were unable to reproduce. This study was attempted to find the effect of LHRHa implantation on oocytes maturation and spawning of Persian sturgeon. Broodstocks were caught from the southeast region of the Caspian Sea. The selected female broodstocks (PI>10) ranged in size from 24.0 to 37.5 kg were implanted with LHRHa cholesterol pellets at concentrations of 0 μg/kg (control), and treatments of 10, 15  and 20 μg/ kg (in three replicates. The results from this study indicated that females treated with LHRHa hormone implantation at 10, 15, 20 µg per kg body weight reached final maturation. These results were observed for all fish from treatment numbers 2 (15 μg/ kg) and 3 (20 μg/kg), however only one fish reached final maturation in treatment 1(10 μg/ kg). The current implantation of LHRHa was able to enhance breeders with PI above 10 to final maturation which under normal condition at sturgeon’s hatcheries this is not possible. The results suggested that final maturation can be achieved that lead to high fertilization (78.33% ±13.87, 68.33% ±4.16 in treatment 2 and 3, respectively) and hatching rates (85.3% ±9.07, 68.33% ±7.64 in treatment 2 and 3, respectively) and also total larvae production. Thus, the information from this study is very useful for artificial propagation of not-fully-matured females of Persian sturgeon at Sturgeon hatcheries especially in Iran.

This study examined the effects of China rose powder (Hibiscus rosasiensis) supplementation (1.5%) on the growth performance, body composition, and pigmentation of blue gourami at different stocking densities (0.6 and 0.9 fish L^-1). Four treatments were assigned in this study: China rose diet+0.6 fish L^-1 (CG0.6), China rose diet+0.9 fish L^-1 (CG0.9), control diet+0.6 fish L^-1 (C0.6) and control diet+0.9 fish L^-1 (C0.9). The results showed that after 70 days, there were no significant differences in growth and body composition between China rose treated groups and their corresponding control groups. Color parameters (L*Lightness, a*redness, b*yellowness) behind the operculum were measured on a weekly basis. Results indicated that in the most of weeks, there were no significant differences for (L*, a*, b*). However in the China rose treatments, the fish were brighter in the first weeks but turned darker in the last weeks. The fish in the China rose treatments had higher greenness and yellowness values at the end of the experiment. The amounts of skin total carotenoids, canthaxanthin and β-carotene in the China rose groups were significantly different compared with the corresponding control groups. Similar patterns were observed in muscle and caudal fin canthaxanthin and β-carotene contents. Significant differences were observed in the content of blood plasma canthaxanthin and β-carotene between C0.6 and CG0.6; whereas such differences were observed in astaxanthin, canthaxanthin and β-carotene between C0.9 and CG0.9 groups. The study shows that the China rose powder is a potent natural carotenoid source for blue gourami to enrich its color in low density.