One of the most important factors that today is important with the risks associated of the growing industry and technology, is plant pesticides that can lead to the destruction of aquatic communities in the long times by entering aquatic ecosystems. So in current study acute toxicity of butachlor poison that is a very common at the agricultural plant was studied in 5-7 gr common carp and Caspian roach for detection of LC50 at 96 hour. Experiment was in static plan and based on the OECD standard conducted for 4 days; water physicochemical parameters including PH, dissolved oxygen and temperature were measured that they were in suitable ranges. Based on the results, acute toxicity of butachlor on carp and Caspian roach were 0.785 and 0.258 mg/l respectively and maximum allowable concentration MAC value were calculated as 0.078 and 0.025 mg/l respectively. According to the standard for determine of the toxicity of various pesticides, butachlor was considered more highly toxic for Caspian roach than common carp.

Due to use of ovulin hormone in the carp breeding centers and lack enough information about the effect of its different concentrations on this fish broodstocks, evaluation of the effectiveness of ovulin hormone in artificial reproduction of carp is essential. This study was performed on 12 male broodstocks of carp with an average weight of 1307.85±169.57g. Fish in 4 groups (each group with 4 fish) were injected at doses of 0.2, 0.25, 0.3 and 0.35mg/kg body weight of ovulin hormone in one time. The injection method was performed peritoneally and below the pectoral fin. Blood samples were taken from fish in two times, before injection and 10 hours after injection. Based on the results, it was found that injection of different doses of ovulin hormone had no effect on red blood cell counts (RBC), mean corpuscular hemoglobin (MCH) and white blood cell counts (WBC) (P>0.05). However, the amount of hemoglobin, hematocrit and granulocytes in all treatments decreased in the blood of male broodstock after the injection of ovulin hormone and the percentage of monocytes increased (P <0.05). It had no effect on total protein and sodium (P>0.05). However, glucose and calcium levels increased and triglyceride, albumin and potassium levels decreased in the studied doses (P<0.05). The levels of cortisol and sex hormones testosterone, estradiol and progesterone in male broodstocks increased in all doses studied (P<0.05). Also, the highest sperm motility and spermatocrit were observed in 0.2 mg/kg, pH in 0.3 mg/kg, triglyceride and alkaline phosphatase in 0.35mg/kg and calcium, sodium and potassium in 0.25mg/kg (P<0.05). The results of this study showed that doses of 0.25 and 0.3mg/kg body weight had the best effect on blood indices, steroid hormones and sperm indices in male broodstocks of carp.

Blood is directly involved in many metabolic processes, and blood and hormonal assessments can be helpful in diagnosing the physiological status of fish. In this study, changes in stress indices (glucose and cortisol) and steroid hormones (testosterone, estradiol and progesterone) of sea carp broodstocks in three stages, before hormone injection, after injection and after artificial reproduction and in different doses of Ovulin hormone were analyzed. For this purpose, male and female carp broodstocks were injected in 4 treatments with doses of 0.4, 0.5, 0.6 and 0.7 ml / kg body weight of Ovulin hormone. Blood samples were taken from each group of male and female broodstocks with 3 fish from each treatment in three stages. The results of this study showed that the injection of Ovulin hormone increases glucose and cortisol and steroid hormones including testosterone, estradiol and progesterone in sea carp broodstocks , but after reproducing, the index decreases ( p <0.05). The highest increase was in the dose of 0.6 and 0.7 and the lowest was in the dose of 0.4 ml / kg. But after reproduction, the value of indices decreased (p <0.05). The results of this study show that hormone injection increases stress and increases the level of sex steroid hormones in fish. In addition, with increasing the dose of injected hormone, the levels of steroid hormones increase even more. A dose of 0.6 ml / kg seems to have had the best effect.

This study was performed to determine the identification (barcoding) using cytochrome oxidase gene of common carp, between three provinces of Golestan, Mazandaran and Gilan (respectively in Gomishan, Tajan and Kiashahr) in 2011. The results of sequencing showed that all samples from the three regions had a genetic distance less than 2%, so all samples were from the same species. The results of sequencing 30 tail samples of carp species on the southern shores of the Caspian Sea showed that all samples are of the same species and their genetic distance does not reach at least 2%. Therefore, all carp samples of the three provinces are of the same species and have the same type of barcode. In the study of nucleotide and haplotypic distance, Gomishan region was 10.75000, 1 and Kiashahr region were 3.200 and 0.9333, respectively. In the study of nucleotide diversity between the two regions, 0.01978 and the average nucleotide difference was 12.187. Haplotypic diversity in Gomishan region was 38.095 and in Kiashahr region was 23.809%. Out of 13 haplotypes, Gomishan region with 8 haplotypes (61.53%) and Kiashahr region with 5 haplotypes (38.46%) had the lowest haplotypes.The results of this study show that there is a significant difference between carp samples in Gomishan and Kiashahr regions in terms of nucleotide and haplotypic diversity (P <0.05).