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In this research the effect of starvation on growth performance, insulin and blood serum metabolites were studied in order to assess compensatory growth mechanism in Persian sturgeon (Acipencer persicus) juveniles with average weight of 108.04± 0.28 gr (± SEM) in the same rearing condition during 8 weeks. This survey was designed in random with 5 treatments in 3 replicates which consist of control group (C, without fasting), 1w (1 week), 2w (2 weeks), 3w (3 weeks) and 4w (4weeks) starvation followed by 4 weeks of re-feeding in satiation. Results revealed that morphological factors including body weight, specific growth rate (SGR), condition factor (CF) and weight gainwere decreased significantly during starvation period.However, growth was increased after re-feedingand weight was compensated in different treatments.In addition, Blood plasma glucose and insulin during fasting and re-feedingdid not change significantly in comparison with the control group. This indicates high performance of this species in themaintenance of blood glucose during starvation and recovery of plasma glucose level after re-feeding. Whereas, plasma total lipid and triglyceride level in fasting treatments were increased. This showed a significant increase in 3w treatment that in 3w treatment(p<0.05), but after 4 weeks ofre-feeding their levels decreased in comparison with the starvationperiodwhich can be due to the energy- resource feature of lipids. The results also showed that Persian sturgeon juvenile can adapt with different long fasting periods and during fasting it can use glycogen and lipids reserves to overcome its metabolic requirements

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Reduction of quality and quantity of wild and farm Persian sturgeon in early life cycle is the most important problems in this endemic and economical species. The purpose of this study was to increase the production efficiency of Acipenser persicus in the first feeding stage to fingerling stage using effect reaction between photoperiod and light intensity. This study was conducted with 13 treatments including 4 photoperiod (24L:00D, 16L:08D, 12L:12D and 08L:16D), 3 light intensity (100, 250 and 450 lux) and one control with three repetition in each treatment (each repeated include 1800 larvae with initial weight and length 41.66 mg and 19.64 mm, respectably) during 60 days. During the experimental period, individual body length and weight were taken at the first and 60th day after the first feeding. All of the fish were fed on live food in the same amount. Biological measurements, including final weight, final length, weight gain (WG), specific growth rate (SGR), condition factor (CF), body weight increase (BWI (and Survival rate (SR), were analyzed. The result indicated that except for survival rate, growth factors were subject to the mutual effect of photoperiod and light intensity, although the final weight and length were affected more by the photoperiod. The growth factors of fish that were in 12L:12D photoperiod with an intensity of 100 lux and 08L:16D photoperiod with an intensity of 250lux were significantly better than others photoperiod and light intensity treatments.

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Persian sturgeon (Acipenser persicus) is one of the most valuable species of fish native to the Caspian Sea and Iran's waters. This study was designed to estimate heritability of Persian sturgeon eggs. In this study, 3 wild Persian sturgeons caught from the south coast of the Caspian Sea in Guilan and transferred to fish breeding programs in Shahid Beheshti rearing and propagation complex were used during 2016. Characteristics including the weight and diameter of eggs at blastula, gastrula and neurola embryological stages. To estimate heritability, 270 eggs were sampled at each stage of fetal development. Variance components was estimated using software R linear mixed model (LMM) closed Lme 4. Results showed that heritability of eggs weight and diameter  at blastula stage 0.218±0.422 and 0.375±0.145 ,at gastrula stage  0.033±0.062 and 0  and at stage neurola was  0.377±0.45 and 0.272±0.564 , respectively. Genetic value in female 3 and male 3 brood stocks was 0.787 and 0.287, respectively. Correlation between these two variables 0.106, 0.44 and 0.43, respectively. Overall, heritability of average egg weight and diameter showed that selection for these traits could be had a positive source of genetic origin.  

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The presence of nanoparticles affects the physiological condition of fish and reduces the immune function of fish, so the use of immune stimulants such as molasses is very important. 250 juveniles of common carp for 42 days in four categories: ration without molasses (treatment 1), ration containing 0.5% molasses (treatment 2), ration containing 1% molasses (treatment 3) and ration containing 2% molasses (Treatment 4) were divided. Then, 50% of the lethal concentration of nano-iron was added to each group for fourteen days. Histological studies of fish exposed to molasses and iron nanoparticles showed structural abnormalities in liver tissue. So that these changes were very different compared to the tissues of the control group. The final conclusion of the present study showed that nano-iron treatment led to tissue damage in carp liver; Although histopathological complication was also observed in the combination of nano-iron and molasses treatments, but the severity of injuries decreased with increasing molasses concentration. The negative effect of iron nanoparticles on normal carp liver tissue by molasses seems to be minimized.