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This project was carried out in the year 2003 in Khuzestan province waters to determine the best artificial propagation techniques for mass production of Barbus xanthopterus. The fish is one of the most valuable and economic species in the area. The propagation was started in late March and continued till late April while suitable temperature was 21-24.5 C. A number of 23 female broodstock with mean weight and length 3.85±0.45kg and 64.95±21cm respectively with a sex ratio of 2:1 male to female were used in the process. The amount of hypophysis injection was 4mg/kg weight of fish and two injections with 10-12 h interval to 10:90 were undertaken. Spawning success was 87% in broodstock. Latency period was 15- 17h and the incubation duration was 59-60h in 23-25 C.The fish eggs has a low stickiness and the count of dry and water-absorbed eggs were 480±32 and 287±25g, respectively. In the twice-injected broodstock, the fertilization rate was 77.22±3.1%, the hatching rate was 81.2 ±1.89% and the survival rate was 83.4±2%. Size of the dry and water-absorbed eggs was 1248±45 and 2110±125, respectively. Washing time with fertilization liquid was 10 min for removing stickiness. In the end, 660 thousand larvae were produced and released to earthen ponds for culture.

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The object of this study was to investigate the status of physicochemical parameters and nutrients in demersal fishing grounds in the Iranian waters of the Persian Gulf from the Hormozgan province to Khuzestan province, from autumn and winter of 2017 to 2020. The local data of physical and chemical parameters of water were recorded and analyzed, by using a CTD (Conductivity, Temperature, and Depth)  device, during 2017, 2018 and 2020 years. Also, the sea surface temperature and chlorophyll-a were recorded from the MODIS (Moderate Resolution Imaging Spectroradiometer) satellite, aqua sensor, in 2018 and 2019 years. The average of remote sensing data of sea surface temperature and chlorophyll-a were 22.83 C° and 1.80 mg.m^-3, respectively in the studied area, from 2018 to 2020. The average of local data of water temperature, chlorophyll-a, salinity and pH were 21.53 °C, 0.84 mg.m^-3, 39.53 ppt and 8.28, respectively in the studied area during the years 2017, 2018 until 2021 winter. The average of concentrations of nitrate, phosphate and silicate were 0.034, 0.008 and 0.517 mg/L, respectively, in the present study. Based on the results, the amount of chlorophyll in the Persian Gulf has a relationship with the sea surface temperature and silicate. By increasing the sea surface temperature and concentration of silicate, the chlorophyll-a increases in the studied area. Changes in the concentrations of nitrate and phosphate had no significant effect on the concentration of chlorophyll-a in the studied area. The average of sea surface temperature and the concentrations of phosphate and silicate increased, but the concentration of chlorophyll-a and nitrite decreased from 2018 autumn to 2020 winter.

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This study aimed to compare reproductive indices of broodstocks between and within (control and selected treatments) four different populations common carp of Hungarian-originated (TATA), North Iran, China-originated (RAN), and South Iran (Khuzestan). Control and selected treatments in each population comprised the average of the broodstock population and those chosen deliberately from 30% above the population mean (apart from shooter fish with excessive growth and out of the normal range), respectively, to calculate the genetic progress. Male and female reproductive indices were checked respectively by evaluating sperm quality (spermatocrit, sperm density per milliliter, percentage of motile sperm, and motility duration) and measuring working and relative fecundity, ovum and hydrated egg diameter, fertilization rate, hatching rate, the larval survival rate, and larval size after hatching. The results showed that, despite the high fecundity in the South Iran population, it has the lowest egg diameter and larval survival rate (p<0.05). Although the China-originated (control and selected treatments) population had the lowest sperm volume, sperm density per milliliter, and percentage of spermatocrit among different populations, the selected-treatment had the highest motile sperm percentage and the motility duration, which resulted in the most elevated fertilization rate belonging to it (p<0.05). The highest survival rate 24 hours post-hatching was observed in China-originated (control and selected) and North Iran-control, and the lowest in TATA (control and selected), North Iran-selected, and South Iran populations (p<0.05). China-originated control population gained the highest larval survival rate 72 hours after hatching. Although it did not differ significantly with the North Iran (control and selected) and TATA-control (p>0.05) populations, it has meaningful difference with the South Iran, TATA-selected, and China-originated-selected (p<0.05). The larval size in TATA-selected, North Iran-control, and South Iran is significantly smaller than other populations (p<0.05). There is no considerable difference in larval length size of the North Iran population between the control and the selected treatments, but it is significantly more in control than selected treatments in the China-originated and TATA populations. This finding illustrated that the selective breeding of broodstocks did not affect the reproductive indices within populations and the larval survival rate in F1. However, it improved the larval size. China-originated and North Iran populations performed satisfactorily in male and female reproductive indices, respectively, and it is worth bringing into mind hybridization between the two populations in future studies.