homayoun hosseinzadeh sahafi

One of the global aproches to ensuring fish security involves aquaculture and using aquatic protein.in this context, fish production can engage to the coastlines and marine environments. International statistics in 2020 indicated the unique role of marine aquaculture production and development in the world. A significant part of aquaculture production (122.6 million tons), about 33.1 million tons belongs to coastal and mariculture. The global production of seaweed (35 million tons) should also be added to this statistic, which includes a total of 68.1 million tons. Marine aquaculture in Iran creates a good opportunity to produce a variety of aquatic products, which, taking into account the components of sustainable development, ie. attention to the basics of the environment and economic and social aspects. Mariculture also provides the field of productive employment. Today, due to some production limitations in inland waters and lack of fresh water in non-coastal provinces, the approach of using marine waters in the north and south of the country (the Caspian Sea, the Persian Gulf, the Oman Sea) has been formed and is expanding. in this regard, useing marine areas for fish production in various types sea cages, as well as the seaweed production and cultivation of all types of oysters and mollusks, along with the balanced development of shrimp production in the seventh national development plan (Including the general policies of the sea-oriented economy) is recommended.

This study was conducted with the aim of investigating the effect of alprazolam on sex steroids, ovarian tissue development and oocyte ultrastructure of three spot gourami after bromocriptine induction. A number of 90 adult female three spot gourami fish were purchased and divided into six groups of 15, including intact control group, solvent control group, bromocriptine control group, and three treatment groups receiving bromocriptine with a dose of 1 mg /kg and alprazolam with three doses of 1, 2, and 4 mg/kg. The drugs were injected intramuscularly in such a way that, control and treatment groups received bromocriptine in one day and the next day treatment groups received different doses of alprazolam. After completing the injections, the fish were euthanized and dissected. The ovaries of the fish were also removed to be examined by optical and electron microscopes. The tissue fluid was used to measure steroid hormones by ELISA kit. In the bromocriptine control group, steroid hormones had a sharp drop and the oocytes were in the peri-nucleolar stage. In treatment groups with bromocriptine and alprazolam at a dose of 4 mg/kg, the levels of 17β-estradiol and testosterone was higher than all control and treatment groups (p<0.01) and oocytes were in vitellogenin stage. Therefore, a high dose of Alprazolam was the stimulant of gonadal development and oocyte growth in three spot gourami fish. it can be concluded that bromocriptine blocked the HPG axis and alprazolam caused re-stimulation of this axis, oocyte maturation and ovarian sex steroid secretion.

Fisheries tourism is a relatively new style of tourism in many countries, which has brought many benefits to both sectors by merging the tourism and fishing sectors. To create and develop fisheries tourism, the participation of the local community, including the fishermen community, as one of the most important groups related to fisheries tourism, is considered an effective tool and an important element. Among the most important prerequisites for the participation of communities in the development of fisheries tourism is the intention of these communities to participate. Therefore, this research was conducted with the general purpose of investigating the intention of fishermen to participate in fisheries tourism and the factors affecting it. This research is practical in terms of purpose, is descriptivr - correlational in terms of analysis, and has been carried out through survey relying on the theory of planned behavior. The statistical population in this research was fishermen who are members of beach seine cooperatives in the Caspian Sea Coastline(N=9594). Due to the distribution of fishermen in the three provinces of Golestan, Mazandaran and Gilan, the sample size of the study was determined to be 209 fishermen and the samples were selected using the multi-stage random sampling method. Data collection was done using a researcher-made questionnaire, which was designed based on the theoretical framework of the research and based on the The Decomposed Theory of Planned Behavior (DTPB). The results showed that fishermen who are members of beach seine cooperatives in the Caspian Sea Coastline have a high intention to accept and participate in the implementation of fisheries tourism. The results also showed that participation in the program "watching the local fish markets by fisheries tourists" has the highest level of intention among all fisheries tourism activities among the fishermen of beach seine cooperatives. They also expressed their intention to participate in programs for "watching beach seine fishing and throwing nets". "staying in the house of local people and being familiar with local fishing communities (cultures and customs)" and cooperation to "participation in local festivals related to fisheries" were other activities that fishermen were interested in participating them.

The communication axis between hypothalamus-pituitary-gonad (HPG) is the basis of the reproductive process in vertebrates. In this study, the effects of salbutamol injection after Cabergoline injection, which is an inhibitor of the HPG axis, were investigated on the ovary. The number of 105 pieces of female three-spot gourami fish was divided into 7 groups of 15, including 3 control groups and 4 treatment groups. Three control groups included intact fish, receiving normal saline (solvent) and Cabergoline at a dose of 25 micrograms per kilogram of fish body weight. The treatment groups received Cabergoline on one day and salbutamol on the next day with doses of 1, 3, 10 and 20 mg per kilogram of fish body weight. Injections were performed every other day and intramuscularly, between the lateral line and the dorsal fin. At the end, after complete anesthesia and death of the fish, sex hormones and ovarian tissue were examined. Statistical evaluation showed that after salbutamol injection, 17-beta-estradiol and gonadosomatic index increased, but the testosterone level decreased (P<0.05). Histological and ultrastructural studies of the ovary also showed that cabergoline inhibited oocyte growth and salbutamol stimulated it.

Effective anticonvulsant drugs each selectively suppress the abnormal activity of neurons to some degree. However, their mechanism of action and efficacy differ in different types of epilepsy disorders.

Investigation of histological effects of 4chloro-N (2-(4-methoxyphenil)-4-oxotiazolidin-3-yl)-2-phenoxybenzamid compared to Diazepam as a reference drug on Trichogaster trichopterus ‘s liver which has done at the fish lab of Islamic Azad University.

In this study, 150 fish specimens with an average weight of 2 ± 0.5 gr were bought from Khan-mahi fish farm. This study was performed on 4 treatment groups (1, 3, 5, 7 mg/kg b.w.) and three controls including, control 1 (intact), control 2 (solvent tween 80), reference control (Diazepam 3 mg/kg.b.w). Before dropping fishes into the aquariums, dechlorination of water was performed in 24 hours, and physicochemical factors were measured. Injections were performed every other day for 20 days and all the treatments were anatomized and their livers put into the fixative to check by optical and electron microscope later.

The results showed that the ALT, AST and ALP were changed in controls to treatments. These results showed a significant difference between the control and the treatment groups (P≤0.05) Microscopic images also showed membrane changes, rupture, gaps between sinusoids, and necrosis at a dose of 5 mg /kg body weight and was in a dose-dependent.

The aim of the present study is to investigate the growth performance and sexual maturation process of female rainbow trout reared in a cage in the Caspian Sea (Mazandaran- Nowshahr). Rainbow trout with an average weight of 122± 5 g were stocked into a cage located in Caspian Sea. Fish were fed daily and random sampling was done monthly (January 2015) to May 2016. Weight and length of thirty fish were measured; their gonad and liver were weighted; total length, total weight, liver and gonad weight, condition factor, GSI and HSI and oocyte diameter were calculated; their blood samples were collected and the levels of 17 beta estradiol, testosterone, progesterone and the vitellogenin were measured; also gonad tissue samples were prepared and examined using a light microscope. The results showed optimal somatic and gonadal growth of fish caged in the Caspian Sea. Sex hormones and vitellogenin levels increased significantly (P<0.01) during the study period. The levels of 17 beta estradiol, testosterone and progesterone in January were 0.56± 0.05 ngml-1, 0.50± 0.05 ngml-1and 0.14± 0.01 ngml-1 respectively and reach to 1.63± 0.13 ngml-1, 0.80± 0.01 ngml-1 and 0.28± 0.03 ngml-1 in May, respectively. Vitellogenin levels increased from 382.40± 55.26 ngml-1 in January to 651.40± 86.34 ngml-1 in May. The gonads developed to stage 4 and the oocyte diameter increased significantly (P<0.01) during the study period. The findings of present study show that female rainbow trout are able to have appropriate somatic growth in the brackish water of the Caspian Sea like fresh water, and the natural process of sexual maturation won’t be disturbed.

251 specimens of kutum fish caught by bony fish persine on the southern shores of the Caspian Sea (Mazandaran) during the years 2017-2019 were studied to study the growth trend of this species. In this study, maximum estimated length (L∞) and annual growth coefficient (K) of kutum fish were estimated 71.79 cm and 0.13, respectively. The results of natural reproduction of this species in Kheirud river with a length of 2 km showed that in 2017-2018, more than 30,000 breeders (female) of anadromous fish migrated to Kheirud river for reproduction and more than 97% of it were kutum fish. As a result of this study, more than 525,000 kutum fish fry were produced and prepared to migrate to sea. (2017-2018). The results showed that the partnerships of fishermen and local rural communities can have a positive effect on the natural reproduction Influence coefficient of kutum fish (P <0.05). The results showed that the penetration coefficient (effectiveness) of fishermen (35%) and rural women (30%) ) were more than the students' effectiveness (16.7) (P <0.05). Thus, by protecting the natural reproduction of kutum fish, other species of anadromous fish have reproductive successes in the Kheirud river, which will establish the desired ecological balance and exploit the ecological carring capacity of the ecosystem.

In this study, we aimed to investigate the effect of serotonin on the lower levels of HPG by blocking the upper HPG axis.90 pieces of three spot Gourami fish with an average weight of 3±1 gram were bought from the Khanmahi fish breeding center. The fish were divided into 6 groups. Intact Control group, solvent (Ethanol 70º) group, bromocriptine control and 3 treatment group received bromocriptine and escitalopram in three doses of 1,5 and 10 milligram per kilogram body weight. The injection was given intramuscular (IM) every other day. The fish were dissected and ovarian tissues dissected for light and electron microscope. After tissue fluids preparation, steroid hormones were measured with a special kit. Based on the results of the second dose of escitalopram and bromocriptine which was the predominant stage of vitellogenesis and gonadal index, it can be concluded that serotonin receptor may be present at the lower levels of the HPG axis.

Swan mussel, Anodonta cygnea, is a freshwater bivalve inhabitant of Anzali wetland, which population is in danger due to pollution and habitat destruction by human manipulation. In the present study, some reproductive traits of this species were evaluated for one year period using microscopic and biometric studies. The mean length was 10.6±0.1cm, the mean width was 6±0.04cm, the mean height was 4±0.04cm, the mean weight was 132±3g and the mean age was 6±0.1 years old. In all shells, two sexes were separated. There was no external feature for sex determination. The frequency of female was 1.5 times that of male. The mean diameter of mature oocyte and sperm were 139.95±8.1 and 4.5±0.26μm, respectively, and the mean area of ​​them was 15255.58±1834.4 and 9.1±1.16μm2, respectively. The mean fecundity was 107844.6±20621.9. Both of male and female gonads were in developing phase in spring (May and June) and in summer (July and August). The spawning stage occurred in the fall and the post-spawning stage in the winter. The development of glochidia were completed in January and the release of them from the gill were occurred between January and March.

The involvement of adrenergic and dopaminergic receptor subunits are recognized in regulating fish repoduction. The potential for neuroendocrine novel pharmaceutics to induce final maturation and ovulation has not been well studied. The aim of the present study was to investigate the effects of new catecholamine pharmaceutics at different doses, including clozapine and olanzapine (the third generation of D4 and D2 dopamine receptor antagonists, respectively), which could be more effective than the first and second generations, salbutamol (β2-adrenergic receptor agonist) and metoprolol (β1- adrenergic receptor antagonist) as compared with ovaprim (D-Ala6,Pro9-Net)-sGnRH+Domperidone, on final oocyte maturation (FOM), ovulation and spawning in Rutilus frisii kutum. In the present investigation, 126 gravid females were injected once with ovaprim, 0.5mlkg-1 BW, salbutamol sulphate (SLB) 2, 4 or 8 mg kg-1 BW; metoprolol tartrate (MTP) 5, 10 or 20 mg kg-1 BW; olanzapine (OLZ) 2, 5 or 10 mg kg-1 BW; clozapine (CZ) 2, 8 or 12 mg kg-1 BW (N=9), been divided into 14 groups. Intact and ovaprim were negative and positive Control groups respectively. The results showed that all fish dosed with 0.5 ml kg-1 of ovaprim ovulated within 13 hours after injection,while no fish ovulated in negative control group (Intact). The parameters include ovulation index, fertilization success, relative fecundity and the number of eggs which were the highest mean values belonged to ovaprim treatment. Ovulation succes (100%) was obtained in OLZ 5 mg kg-1, CZ 12 mg kg-1, MTP 5 mg kg-1 and SLB 4 mg kg-1 treatments. Therefore, it could be concluded that SLB 4 mg appears to employ β2-adrenoceptor mechanisms in mediating the considered effects. In contrast, MTP at high doses (10 mg and 20 mg) significantly inhibited the stimulatory effect of adrenergic system on FOM and ovulation. The stimulation by the blocker (MTP) was higher in the low dose, 5 mg kg-1. The successful spawning using CZ 12 mg and OLZ 5 mg are important steps in the expansion of the culture of Caspian kutum.

In addition to the development of new technologies to improve the biological conditions of cultured fish, the biochemical nature and physiological functionality of those feed additives strongly affect the stress response. This study explores the effect of dietary arachidonic acid (ARA, 20:4n-6) levels compared with cortisol and glucose levels and whole fatty acid composition in the using Zebrafish as the model organism. Juvenile zebrafish (20-days post-fertilization) fed the five iso-nitrogenous and iso-energetics experimental diets utilizing different ratios of the ARA diet (0, 0.5, 1, 2, and 4% ARA of total fatty acid) for 70 days. Then, Whole-body cortisol and glucose levels were determined, after short-term stress (48 hours’ exposure to starvation). Results showed that the muscle ARA levels were highly correlated to dietary ARA levels. The experiments revealed significant, High ARA levels (2% and 4%) seemed to affect lipid metabolism in complicated ways (p < 0.05). Fish reflected dietary ARA content and post-stress cortisol increased with ARA supply up to 1%, whereas 4% ARA seems to enhance basal cortisol slightly and alter the response to stress. Actually, our results indicate that an ARA-enriched diet induces changes in complex lipids, cortisol and glucose levels, and Overall affect physiological parameters.

Long-chain polyunsaturated fatty acids (such as Arachidonic acid, ARA, C20:4 n-6) have unique roles in controlling and regulating growth performance, lipid metabolism, cell membrane fluidity, and immune function in fish. This research was conducted to produce higher quality and resistant zebrafish using arachidonic acid diet to achieve the best growth and survival rate. Five experimental groups were established and fed diets with different levels of ARA corresponding to 0 (control), 0.5, 1, 2 and 4% of total fatty acid.  Zebrafish larvae (20-days post-fertilization) were fed ad libitum 5 times daily for 10 weeks. Both weight and length were recorded to determine growth indices. Although there were significant differences in general growth demographics (length/weight) after the 10-week feeding trial, no significant differences in the overall survival rate of Zebrafish. Increase in dietary Arachidonic acid (up to 2%), maximum final weight (0.38 ± 0/01 g), body weight gain (0.32±0/16), body weight gain percent (613.42 ± 28/44), daily growth rate (0.46 ± 0/02) and the lowest feed conversion ratio (2.24 ± 0/05) were higher than other treatments. The results show that ARA has a significant influence on the growth factors of Zebrafish.

Controlling reproduction in captivity is indispensable for aquaculture. In some fish, spawning conditions can be made by manipulating the light period and water temperature. But in many breeding fish, the progression in each stage of reproduction requires the administration of hormones from outside the body of the fish. In some fish, these hormonal manipulations are just as a management tool for increasing egg production and ease of work in the workshops. As for the rest of the fish, external hormones are the only way to produce eggs that will surely be fertilized. Hormonal manipulation of breeding fish is based on the use of the LH luteinizing hormone that acts directly on the gonadal surface, or on the synthetic agonists of the GnRHa gonadotrophin releasing hormone that acts on the surface of the pituitary to induce endogenous LH. Today, there are relatively few known hormones in finch fish, a relatively small amount of protein production. But those that have been cultivated have played a decisive role in aquaculture production systems, and their use in an appropriate framework and in a safe and sustainable way is not expected. In this paper, in addition to reviewing mechanisms for regulating reproduction in fish, important natural and artificial hormones used in aquaculture in the world and Iran, and their scientific and practical applications have been analyzed.

Today, the influence of estrogen on the natural sex hormones in fish have been proven as a contributing factor.The effects of Vitexagnus-castus extracts were investigate on gonadal structure and reproductive performance of goldfish (C.auratus).Maturing females (n=180) with an average weight of 16/5 ± 0/8 g was stocked for 48 hours after adaptation to the environment. Physical and chemical factors such as pH(6.5), dissolved oxygen(6.5), temperature(26) adjusted to optimal condition. FToday, the influence of estrogen on the natural sex hormones in fish have been proven as a contributing factor. The effects of Vitex agnus-castus extracts were investigate on gonadal structure and reproductive performance of goldfish (C. auratus).Maturing females (n=180) with an average weight of 16/5 ± 0/8 g was stocked for 48 hours after adaptation to the environment. Physical and chemical factors such as pH (6.5), dissolved oxygen (6.5), temperature (26) adjusted to optimal condition. Gold Fishes were separated in 8 groups (2 control groups and 4 treatment groups) with three replications, each group contains 15 fishes. Different doses of extract (10, 20, 30 and 50 mg/kg) were injected intramuscularly (IM) for 20 days (10 times). Fishes were anesthetized after 21 days length and weight were measured. Gonads were taken for estimating gonadosomatic condition. Histological studies were considered by tissue processing and staining with H & E using light microscope. After blood sampling, Sex hormones (testosterone and 17 ß-estradiol) were determined by radioimmunoassay. 17- ß estradiol were decrease in all treatments copair to control groups and had dose dependent significant differences (P<0.01). Testosterone in 30 and 50 mg/kg treatments were also decreased significantly. Gonadosomatic index at 30 and 50 mg/kg treatments showed the same pattern witch supporting the inhibitory effects of Vitexagnus-castus extract on growth and development of oocyte and reproductive performance of fishes.

To investigate the effect of probioenzyme on growth, nutrition, hematology and immune response in rainbow trout (Oncorhynchus mykiss),this matter was supplemented at 0.3, and 0.5g/kg diet(treatments of 2 and 3 respectively) and control group(treatment 1: no food supplemented probioenzyme) in three treatments with three replications. This survey was performed in nine 200ltanks containing 30  fish(average weight: 26.3± 2.7g) in each tank for 60 days. At the end of the feeding period, the growth and blood factors analyzed. Based on the results, there is no significant difference between treatments 1, 2 and in growth, nutrition and blood erythrocytes factors(P >0.05). The mean white blood cells and blood cells neutrophil percentage in treatment of 3 was significantly different (P <0.05) from the control group fish. Significant differences in serum complement components in the treated groups were in comparission to control group (P <0.05). ACH50 activity and immunoglobulin (IgM) did not show significant differences between treatments (P> 0.05). The lysozyme and serum globulins in treatment 3 compared to the control treatment was higher and statistically significant (P <0.05). Although there weren,t signs of significant effects of probioenzyme on growth and nutrition factors, Probioenzyme can have immunological effects on rainbow trout.

The advancement of modern technology and its many uses in the environment, especially the aquatic ecosystem, has caused, in addition to humans, other organisms, especially fish, to be affected by its margins, including the effects of electromagnetic waves emitted by them. Therefore, attention to the effects of these waves on fish as the most important inhabitants of aquatic environments is necessary with economic aspects. The aim of this study was to investigate the effect of mobile electromagnetic waves (900 MHz) on gonadal and liver weights, GTH II and ovarian tissue structure of angel fish female brooders during 10 days and in 3 experimental groups including: 1) control (without receiving Waves), 2) 4 times a day and each time for 30 minutes in faced with mobile phones in a standby position, and 3) 4 times a day and each time for 30 minutes in faced with mobile phones in a calling mode. At the end of the test after blood sampling, centrifugation and serum separation, GTH II was measured by radio immunoassay (RIA). The broods were then biometrically analyzed and scattered. The histological section of ovaries were prepared by the classical method of histology with hematoxylin-eosin staining, and microscopically evaluated for quantitative and qualitative examination. The gonadosomatic and hepatosomatic index as well as the mean level of GTH II in treatment group 2 was significantly higher than control group and treatment 1. No brooders of treatment 2 spawned. The number of atresia in treatment 2 was higher than that of other groups. The results showed that mobile-induced electromagnetic waves produced significant changes in the reproductive indices of female angel fish. However, more extensive studies are needed in the future.

Caspian Kutum (Rutilus frisii kutum Kamenskii, 1901), is one of the most valuable commercial and endemic fish in the Caspian Sea. The aim of the present study was to evaluate the effects of the third generation dopaminergic pharmaceutical compounds antagonists and adrenergic agonist and antagonist pharmaceutics with Buserelin (GnRHa) on plasma levels of 17β-estradiol (E2) and 17α-hydroxyprogeterone (17α-OHP) in this species. 117 gravid female were selected for the study, pharmaceutics including, Buserelin Acetate (BUS) 5 μg kg-1 BW, Ovaprim, 0. 5 ml kg-1 BW, Salbutamol Sulphate (SLB) 4 mg kg-1 BW, Olanzapine (OLZ) 5 mg kg-1 BW, Clozapine (CZ) 12 mg kg-1 BW و Metoprolol Tartrate (MTP) 5 mg kg-1 BW. Pharmaceutics were divided into 10 groups: Group 1: OLZ+SLB, Group 2: OLZ+MTP, Group 3: OLZ+BUS, Group 4: CZ+SLB, Group 5: CZ+MTP, Group 6: CZ+BUS, Group 7: OLZ+BUS+SLB, Group 8: OLZ+BUS+MTP, Group 9: CZ+BUS+SLB, Group 10: CZ+BUS+MTP. Saline 0. 7% and Inact were considered as the positive and negative Control respectively, also Ovaprim was the evidence treatment (n=9).
The results showed that the level of E2 was increased before administration of pharmaceutics in 0 h, but was decreased followed by pharmaceutics administration (12 h), so that Ovaprim, OLZ+BUS+SLB and CZ+BUS treatments were significantly differed compared with other treatments (P<0. 01). Also the treatment OLZ+SLB, OLZ+MTP, CZ+SLB, OLZ+BUS+MTP and CZ+BUS+SLB were significantly differed in P0. 05). The level of 17α-OHPwas low before pharmaceutics administration in 0 h, but was increased after administration of pharmaceutics (12 h). Ovaprim, OLZ+BUS+SLB, CZ+BUS and OLZ+SLB treatments were significantly differed in compared with other treatments in 12 h (P<0. 01). it could be concluded that, dopaminergic system was inhibited reproductive functions while adrenergic system stimulated it, thus there was an inverse relationship between the dopaminergic and adrenergic systems. So that adrenergic system agonist can be used beside the third generation Dopamine antagonists and GnRH analogue in Caspian Kutum.

Origanum vulgare was used as an effective herbal for infertility treatment in traditional medicine. The present study compared the effects of the hydroalcoholic extract of the air branch of Origanum vulgare، LHRH-A2، and17β-estradiol on the ultrastructure of oocyte and pituitary in immature Trichogaster trichopterus. For this purpose 60 pieces of Trichogaster trichopterus with average weight of 2. 1±1gram were divided into 6 groups: saline، placebo، ethanol and 3 experimental groups (Origanum vulgare and 17β-estradiol at a dose of 50 mg/kg and LHRH-A2 at a dose of 0. 005 mg/kg) (each group 10 fish). Fish were injected intra-muscularly، one dose every other day and seven doses in total. Ultrastructure of oocyte and anterior pituitary in the three treatments were measured and compared with control treatments. The results showed that the size of oocytes follicle and the mean diameter of Golgi vesicles in Origanum vulgare treatment was higher than that in LHRH-A2 treatment، but there were lesser than that in 17beta-estradiol treatment (p≤0. 05). The results of the ultrastructural comparision of the anterior pituitary showed that in Origanum vulgare treatment the number of small cells increased and made a few large granules in gonadotroph cells. In fish treated with 17β-estradiol the number of large granules increased significantly، whereas in LHRH-A2 treatment large granules were lysed and stimulation was complete. The present results suggested that the Origanum vulgare affected Trichogaster trichopterus fertility.

The effect of Kutum (Rutilus firisi kutum) stock enhancement for homing behavior and imprinting with morpholine were studied during 2004 to 2008. This species is a migratory anadromous fish, spawning in rivers in March–April. It has a group synchronous and single spawning behavior. Total of 15, 930 Tagged (ABC Tags) specimens of Kutum fingerlings were released into the Khoshkroud river estuary (South part of the Caspian Sea). Kutums were treated with synthetic amine based odorant morpholine (C4H9NO) with different concentrations (5x10-2. 5x10-5 and 5x10-7 mg/lit) to enhance imprinting of natural river odors and promote homing behavior. To find the best time of exposing at various developmental stages, Kutums were treated with 5x10-5mg/lit morpholine in yolk sack, active larvae, 2-3 g. fingerlings and 4-5 g. fingerling stages. Results revealed that significant differences (P<0. 001) existed between kutum homing rate exposed to 5x10-5 mg/lit (0. 5 %) with other treatments i. e. 5x10-7، (0. 16%) and 5x10-2 (0. 1%) as well as with control (0. 02 %), during the experimental period. Total Return rate was 0. 32%. Results showed significant differences (P<0. 001) between kutum return (homing) rate in active fry stage (1 %) compared to other stages, i. e., yolk sac fry (0. 23%), 2-3- g fingerling (0. 23%), 4-5 g. fingerling (0. 26%) and control (0. 13%) during the tree years of experimental period. There were significant differences in sex ratio [M (1. 42): F (1)] in recaptured kutums in khoshkrud river (x2=6. 4 α= 0. 05 df= 1). Average recapturing rate was greater (6. 7 %) than the average recapturing rate for the 5 year period of 2000 to 2004 (5%). As such, it is suggested that revealed that morpholine could be used for return rate enhancing of kutum. Results reviled the role of morpholine as an pheromone like substance for enhancing migratory behavior of Kutum (Rutilus firisi kutum) fish.