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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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Nowadays the production of resistant larva with high survival and desirable growth is so important in aquaculture industry. Due to the fact that larvae’s digestion is not completed after the absorption of yolk sac, the alive food should be used in this step. In this investigation, the Iranian Acipenser percicus larva growth and survival in 3 treatments feeding on 3 alive foods, Caspian Sea Acartia, Artemia and Daphnia were studied and each treatment in 3 replicates were done during 14 days. Experimental larval  feeding results showed significant difference  in final weight indicators, survival rate, food  conservation ratio, gain weight percentage, specific growth and daily growth (p<0.05). The final obtained results showed that the best growth indicators were gained in the treatment fed by Caspian Sea Acartia was and the treatments fed by Artemia and Daphnia were placed in further ratings

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In the present study clove oil extract as an anaesthetic in juvenile Persian sturgeon (Acipenser persicus) has been studied. To this end, 150 juvenile Persian sturgeons with average weight of 76.55 ± 2.15 gwere divided into15 fiberglass tanks. Then three treatment groups, one negative control group and one positive control group, each with three replicates, were considered. The fish of control groups were exposed to 50, 100 and 150 mg/l of clove oil extract as anaesthetic, respectively. Results indicated no statistical difference in stages of anaesthesia for different clove oil extract concentrations. Anaesthesia and recovery times were calculated as less than 3 minutes for all drug concentrations. According to histological examination, no pathologic sign was detected in kidney, liver and gill tissues of the sampled fishin the anaesthesia test in different concentrations. In long time exposure (20 minutes) to 150 mg/l clove oil extract oedema and epithelium lifting in secondary lamella of gill was recorded but no pathological sign was observed in kidney and liver tissues. Due to the results of the present study, the 50 mg/l clove oil extract is recommended as a standard anaesthesia for juvenile Caspian sturgeon. Also, elevation of this drug dose to 150 mg/l is acceptable and has no histopathologic effects in this fish.

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In the present study, we investigated the effects of short –term exposure (96 h) and sub-lethal concentrations of diazinon on energetic (glucose, lactate) and osmotic parameters (chloride cells number, cortisol, total protein, blood plasma ions) of Persian sturgeon juveniles (Acipenser persicus) during salinity adaptation to seawater. 500 fish were distributed in twelve 100 L tanks at density of 40 fish per tank. The experimental treatments were: (1) 0.3 ppm (%10 LC₅₀ 96 h) diazinon, (2) 0.9 ppm (%30 LC₅₀ 96 h) diazinon (3) 1.5 ppm (%50 LC₅₀ 96 h) diazinon. Also, one diazinon-free group was considered as control. The experiment was conducted in two stages including: 96 h exposure in freshwater (FW) and 24 h exposure in brackish water (BW: 12 ppt salinity). After each stage, blood and gill tissue samples were taken. The results that diazinin can affect energetic and blood osmotic parameters of Persian sturgeon juveniles before and during the salinity adaptation period, especially in high concentrations (including 0.9 and 1.5 ppm).  These effects includes: (a) 96 h exposure in FW: increase in cortisol, glucose, lactate and number of chloride cells (only in 0.3 ppm group) and decrease of ions. (b) 24 h exposure in BW: increase in cortisol, glucose and ions. In conclusion, our study showed that sub-lethal concentrations of diazinon (especially 0.9 and 1.5 ppm) reduce the potential of osmoregulation of the Persian sturgeon juveniles during salinity adaptation to seawater. These effects were: decreases in number of chloride cells, increases in stress indices (cortisol and glucose), changes in permeability of gills tissue and causing anaerobic condition which can affect the success of rebuilding the reserves of this precious species.

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The present study aims at investigating hematological and biochemical parameters (electrolyte and non-electrolyte factors) in two species of Acipenseridae, A. persicus and H. huso among three different ages, fry (2-7 months), juvenile (1-2 years) and brood stocks (7years). The study was conducted in Caspian Sea Sturgeon International Research Institute in 2012 during six month (spring and summer). For this purpose, 30 A. persicus and 30 H. huso were used (10 fry fishes, 10 juvenile fishes, 5 female and 5 male brood stocks in each group). Comparison of means of hematological and biochemical parameters revealed a significant difference among the three groups regarding potassium ion in H. huso and MCH and monocytes in A. persicus in all the indices except for RBC, MCHC and glucose. (p<0/05). But in terms of sex, significant statistical difference was only observed in glucose and potassium ion in H. huso species and in albumin, chloride and sodium ions in A. persicus (p<0/05). By investigating the present results, it can be stated that age, species and sex (broodstocks) is the most effective in the change of biochemical and blood indices.

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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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Bone gla protein and matrix gla protein are of common origin with evolutionary relation and have similar structural features and are functional in the formation of skeletal structures The present study have been evaluated the genes encoding vitamin k-dependant proteins (VKDPs) expression at hatching time (0), 1, 3, 6, 10, 12,14, 20, 30 and 50 in skeletal Persian sturgeon sturgeon (Acipenser persicus Bordin, 1897). The results of quantitative real-time PCR showed that the transcripts of VKDPs genes including bone Gla protein (bgp) and  matrix Gla protein (mgp ) were significantly up-regulated during the transition to the exogenous feeding, confirming the hypothesis about the relevance of the above-mentioned genes in chondrogenesis at early developmental stages. Maximal levels of bgp and mgp expression at juvenile stage, indicating the importance of these genes in the mineralization of the skeleton in sturgeons, although these genes are also expressed in other body tissues. This information can be considered as a reference for other studies evaluating the quality of larvae and the influence of rearing biotic and abiotic factors in the skeletogenesis of this sturgeon species and the occurrence of skeletal deformities.
 

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In this study population dynamic of Acipenser persicus with age structure model by Monte Carlo and Bootstrap approach was studied. Length frequency data a total of 4376 specimens collected from beach seine, fixed gill net and conservation force in coastal Guilan province during 2002 to 2012. Data imported to FiSAT II for length frequency analyze by ELEFAN 1. K, L_∞ and t₀ estimated 203, 0.08 and -0.94 respectively. Total and natural mortality estimated 0.26 and 0.14 year^-1 respectively. The exploitation rate (E) was computed 0.61. Confidence limit of Z was obtained 0.195-0.327 year^-1 by Bootstrap method. At Monte Carlo simulation method, confidence limit of Z was calculated 0.169-0.289 year^-1 with considering sampling error. Result of the present paper demonstrating that considering the uncertainty of population parameters of selected species could be useful for increasing the accuracy at stock assessment models. 

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In the present study, the fishing status and production of caviar from wild sturgeon as well as the stocks rehabilitation of these species in the Caspian Sea have been analyzed over the past few years. Unfortunately, due to certain reasons such as overfishing and poaching, destruction of spawning areas and natural habitats, environmental pollution and reduced the number of released juveniles sturgeon, the generation of these valuable species has sharply declined and the catching amount reached only to 13 tons in south parts of the Caspian Sea in 2019. With this situation, it seems that through the upcoming years, the generation of some fishes from the Caspian Sea will become rare and extinct. Meanwhile, attention to aquaculture of these fish, especially beluga and Siberian sturgeon has increased in Iran, so that the amount of meat and caviar production in 2019 was 2830 and 10. 6 tons, respectively. Given the severe decline in the sturgeon stocks, the necessity of rehabilitation of natural spawning areas in the rivers, prevent poaching and continuing stocks rehabilitation under the management of all surrounded countries should be considered in form of a proper "action plan" for the Caspian Sea. Moreover, for more awareness of the public people and the appropriate cultural issues, a certain day is suggested as "National Sturgeon Conservation Day".

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This study aimed to investigate the changes and growth pattern of Persian sturgeon fishing in fishing regions of Golestan and biological characteristics of this species over a period of 10 years. The highest amount of Persian sturgeon fishing was in 2012, when a total of 143 pieces of this species were caught from five fishing grounds in Golestan province, and the lowest amount was caught in 1398, when 49 pieces of this species were caught. in the present study, the maximum total length of Qarabrun was in 1397 with a total length of 257 cm. Mianqaleh fishing farm had the highest number of catches (471 pieces) of this species and the lowest amount of catches (26 pieces) for this species was recorded in Chalasht fishing farm. The results showed that the highest average total length was observed in 2014 and the highest total weight was observed in 2017 and the lowest average total length and total weight was obtained in 2012. The sex ratio of males to females of Persian sturgeon species in the ten-year period was 1.24: 1, where the male population was higher (p < 0.05). The range of growth coefficient (b) for the population of Persian sturgeon in the years 2011 to 2020 varied between 2.60 to 3.82, The results of Pauli test for the relationship between length and weight of Persian sturgeon species showed that the growth pattern of this species in 2011 and 2012 was negative allometric, in 2015 positive allometric and in 2013, 2014,  2016, 2017, 2018, 2019 and 2020 It was isometric. Conclusion of this study shows that in a period of 10 years for Qarahbrun species had a decrease of 75%, so in the waters of Golestan province this trend for Qarahbrun is among the most endangered species and this means an alarm for this valuable species It has been heard in the Caspian Sea.