The effect of various protein levels on the growth and survival rates of Penaeus monodon Fabricius

Postlarvae of tiger prawns, P. monodon, were fed with various protein levels of 0; 30; 40 and 50%, fish meal and rice bran were combined and pelletized for 16 wks. Prawns used had an average mean length of 1.2 mm and an average mean weight of 5.5 mg. Nitrite, ammonia, dissolved oxygen content, temperature and pH were monitored. After one month of feeding, growth increments of postlarvae fed with 30% protein diet were significantly different from those given 0; 40 and 50%. Survival rate of the group fed 40% protein was higher (81.7%) but was not significantly different from those fed 30% (68.0%). The highest feed efficiency was obtained from the 30% protein pellets (4.6). At the end of 16 weeks, growth increment of 40% protein level was significantly different from the 30% and 50% protein levels, but the survival rate was not significantly different from the 30% protein level. Feed conversion for the 40% protein diet was 2.8.

Prevention of infestation by Dermestes maculatus Degeer in east African dried fish by solar treatment

East African sun-dried fish infested by Dermestes maculatus were exposed to tropical sunlight at ambient temperature and analysed for insect mortality and weight losses. Solar treatment for 6 to 8 lo was highly effective for one layer of split sun-dried fish and 100% insect mortality was toted, while pest species were still present in the four layer batch. Weight losses between 1.2% and 10.2% were recorded, the top layer suffering the highest loss. The high surface temperature of 60°C caused fish to become brittle and quality losses occurred. A reduction in length of exposure/temperature is probably a presupposition for application of the method to local conditions.

Status and prospects of mackerel and tuna fishery in Bangladesh

Present status and future prospects of mackerel and tuna fisheries in Bangladesh were assessed during July 2003-June 2004. The work concentrated on the fishing gears, length of fishes, total landings and market price of the catch and highlighted the prospects of the fishery in Bangladesh. Four commercially important species of mackerels and tuna viz. Scomberomorus guttatus, Scomberomorus commerson, Rastrelliger kanagurta, and Euthynnus affinis were included in the study. About 95% of mackerels and tuna were caught by drift gill nets and the rest were caught by long lines (4%) and marine set-bag-net (1%). Average monthly total landing of mackerels and tunas was about 264 t, of which 147 t landed in Cox's Bazar and 117 t in Chittagong sites. Total catches of the four species in Cox's Bazar and Chittagong sites were found to be 956 and 762 t, respectively. The poor landing was observed during January-February and the peak landing was in November and July. Gross market value of the annual landing of mackerels and tunas (1,718 t) was found to be 1,392 latch taka. Nevertheless, the mackerel and tuna fisheries in Bangladesh are increasingly contributing to the marine fish production of the country and have very good potential for further expansion for both domestic and export market.

Generation of 63-nJ pulses from a fiber oscillator modelocked by nanotubes

We mode-lock a fiber oscillator with cavity length of ~1500m using nanotubes, achieving 1.55ps pulses with pulse energy up to 63nJ at 134 KHz repetition rate. © 2010 Optical Society of America.

Embryonic and larval development of Mystus gulio (Ham.)

Mystus gulio eggs are strongly adhesive and contain relatively small yolk (0.75-1.0 mm). The egg envelop is thick and transparent. First cleavage (two cells), four cells, eight cells, sixteen cells and multi cells stages were found 20, 25, 35-40, 60 and 70 minutes after fertilization, respectively. The morula stage was visualized within 1.5 h after fertilization. The heart beat visible and the circulatory system commenced after 16 h of fertilization. Embryos hatched 18-20h after activation of egg. The newly hatched larva measured 2.82±0.03 mm in length and 0.32±0.06 mg in weight. The yolk sac was fully absorbed by the third day though larvae commenced exogenous feeding even before completion of yolk absorption. A 5-day old post larva began wandering in search of food. Ten-day old post larvae endowed with eight branched rays in dorsal fin and seven in caudal fin. Fifteen-day old post larvae had the pectm:al spine become stout though the embryonic fin folds had to be disappeared. The length of fingerlings ranged from 25-30 mm after 30 days, and their external features were just like those of an adult except that they were not sexually matured.

Effects of supplemental feed and fertilizer on growth and survival of Macrobrachium rosenbergii (de Man) post larvae in pond nursery system

The study was conducted to compare the performance of different nursing practices of giant freshwater prawn (Macrobrachium rosenbergii) post-larvae (PL). Three treatments such as only fertilizers (T1), fertilizers with 5% supplementary feed (local feed) (T2), and 10% commercial feed (T3) were applied in the nursing system of prawn PLs in earthen pond. An earthen pond (315m²) was divided into nine equal small ponds by fine meshed nylon nets. Feeds were used once daily on a tray placed near the pond bottom. There was a significant difference (p<0.05) in some water quality parameters like pH and total alkalinity, but all measured water quality parameters viz. water temperature, transparency, dissolved oxygen and ammonia-nitrogen were within the acceptable range for nursing of prawn PL. The results showed that the mean final lengths of prawn post-larvae were 6.3±0.07 cm, 7.12±0.22 cm and 8.17±0.16 cm in T1, T2 and T3, respectively. There were significant difference (p<0.05) in mean final length of prawn PL among the treatments. Significantly higher (p<0.05) average daily weight gain was observed in T3 (0.071 ±0.007 g) than in T2 (0.052±0.006 g) and T1 (0.031 ±0.002 g). The specific growth rate (SGR) of T3 (8.81±0.26) was found significantly higher (p<0.05) than T2 (8.35±0.22) and T1 (7.42±0.11). Survival rate (%) was also significantly higher (p<0.05) in T3 (66.24±1.58) than in T2 (60.52±1.64) and T1 (53.86±2.71). Therefore, it may be concluded that the growth and survival in prawn nursery was better in commercial feed than only fertilizers and fertilizers with local feeds.

Population dynamics and stock assessment of the common carp (Cyprinus carpio) in Iranian waters of the Caspian Sea

In order to come up with the responsible fishing pattern of common carp, there was a need to identify some of the biological characteristics and stock assessment of carp in Iranian waters of the Caspian Sea .The fork length ,weight ,age ,growth parameters of von bertalanffy and mortality rates of common carp were estimated from oct 2006 to sept 2007.Based on the exponential relationship between length and weight in the size range 6.3-65.6 cm ,b was calculated 2.895, 2.843 and 2.925 respectively for combined sexes ,males and females. The mean condition factor was 1.9 which is close to the ideal condition.The results from measuring 3170 specimens ,were showed the first fork length of maturity was 30 cm for males and 32 cm for females. The results indicated that females were predominate and sex ratio was 0.66:1 (M:F) and chi-squares analysis showeda significant difference between males and females.(p<0.05).Length infinity and growth coefficient were calculated by three different methods as below: Length frequency analysis : k=0.17 L∞ =68.04 Age-Length Key k=0.15 L∞ =74.25 Back calculation : k=0.14 L∞ =68.4 The mortality parameters and exploitation rate were estimated as below : Z=0.73 per year M=0.31 per year F=0.42 per year E=0.56 Refer to amount of common carp catch in 2007 -08 ,biomass was calculated 9640.2 tones by jone's cohort analysis and MSY 2374.5 tones.According to analysis ,the number of common carp in the distribution area (Iranian part of the Caspian Sea ) was estimated 24 millions in the 2006-07.

Investigation of polymorphism by PCR-RFLP method in Cobia fish Rachycentron canadum in the Persian Gulf and Oman Sea

Cobia is a native fish species in Iranian waters in the Persian Gulf and Sea of Oman and has a good internal and foreign market. This fish is a fast growing species and for this reason Iranian Fisheries is considering to go for it culture practices. To go for any utilization such as fishing from wild stocks or culture activities, needs a better understanding of its peculiarities and genetic characteristics of its natural resources. Therefore, this project was discribed and conducted. In this investigation, cuts 2 or 3 cm of fin tissue of  specimen of Cobia obtained from Sistan and Bluchestan, Hormozgan, Bushehr and Khuzestan water provinces, were collected. DNA was extracted by Phenol-chlorophorm method and produced PCR product in length of 1060 and 1450 base pair of two mitochondrial genes COI and NADH2. Using 13 cutting enzymes (4 enzymes were subscriber for both of genes), 205 base pair (from 2510 base pair, equal with %3.8 from gene regains) were directly investigated. But binding patterns of enzymatic digestion of PCR products of both COI and ND genes from electrophoresis were monomorph in all samples and no polymorphism was observed. This may be attributed to the unsuitable choice of COI and ND2 genes for showing of intra specific divergence. But in general non-existence of genetic diversity or noticeable decrease of that among individuals has been reported in regions were fish migration exist and they can freely move between two regions. Therefore, non-observation of polymorphism in the study area might be the case and indicates represents the area. On the other hand, some scientists believe that the distributions of populations in different regions are greatly affected by environmental and physical and ecological factors. Althoug Cobia is a migratory fish, but with regard to the fact that the environmental conditions are different (specially temperature and salinity) between east and west of Persian Gulf and Oman sea, there is a possibility that different genetic groups of this species exist in the regions. Of course It is clear that using more samples and enzymes from other genetically regions could produce better results. Since none of the two investigated genes didn’t show genetic divergence or polymorphism amongst the individuals of one region or between different regions, therefore, statistic analysis for estimating of haplotype diversity or nucleotide diversity and drawing of relationship tree among individuals using available softwares was not possible.

Study of density, distribution and yield on benthic fauna and brown trout (Salmo trutta fario) feeding in Laar reservoirs

Lar lake, with the international UTM specification of 39S 579680 3976567 & 39S 589930 3976184 is Situated in Lar national Park with an aerial distance of 55 Km of Tehran along Haraz road. The present research is carried out as part of a comprehensives Plan for assessment of bioresearches of Lar lake & the rivers flowing into it. This research includes examination of there benthic Samplings performed in Lar lake and each of the related rivers including Delichaee, Ab-e-sefid , Alarm & Lar (Kamardasht).Tubifex and Chironomus genus were found to have the highest frequencies of occurrence in the lake with %77.117 & %21.823 respectively followed by Chironomidae and Simulidae from the Diptera order which accounted for %72.328 and %13.812 occurrences in four rivers examined in the Study. The benthic biomass at various examined Sites and the average wet weight of the benthic biomass in station No one in the lake Was 17.397g and the figure for the examined site in Alarm was 20.242 g which were the highest level among Other examination stations the index for the abundance of species in Alarm river was greater than the rest of the examined rivers with 12.57. A sum of 354 Pieces of brown trouts was caught in the course of sampling which were closely investigated in terms of their digestive tract Content. It was identified that Daphniidae and Chironomus constituted the bulk of eaten items from the lake with %17.985 and %63.973 respectively. Meanwhile, Chironomidae and Simuladae were the most frequently eanten benthos by the fish with %81.47 and %7.93 respectively.The index for the relative length of gut was recorded at 0.49± 0.08 which is well indicative of the carnivorous diet of the fish.The index for the feeding intensity amounted to 138  83 showing that the one year old fish were of more feeding intensity.The coefficient of condition (K) was estimated at 1.02  0.142 for all the caught fish. The average wet weight of the benthos was 10.348 g per square meter which if extended to 700ha surface area of the lake, the total macrobenthic production in the lake would amount to 72730Kg of wet weight or 6510 Kg of dry weight. Since the Secondary Production of macrobenthos have always been double that of their biomass, it is reasonable to assume that the Secondary Production of macrobenthos amount to 145640 Kg by their wet weight and Since the energy transfer in the food chain of the lake from benthos to fish is 10 percent, the fish production Capacity Coming from benthic resources of the lake (Lar) would be 14.5 MT, half of which (7000-8000MT) could annually be harvested. Further more, the actual fish Production Capacity might exceed the projected level Since Daphnia, Rotifers and Ostracoda which belong to Zooplanktons, play a part in the natural diet of trout. Meanwhile, rivers Play a major role in fish nutrition and the annual fish production in Delichaee river is about 4481.8Kg while the figures for Ab-e-sefid, Alerm and Lar rivers are 2370.7 4848.7 and 2586.2 Kg respectively, that further increase fish Production in the area and every year half of these resources can be exploitable from the river & the lake.Nevertheless, due to ecological & biological importance of rivers and the probability of environmental Pollution, devastation of natural fish habitats & their nursery grounds, Sport fishing is not recommended at all.

The study of biological characteristics and determination of population dynamic parameters of sawtooth barracuda (Sphyraena putnamae) in the Persian Gulf (Hormozgun Province waters)

The biological characteristics and population dynamisms of Sphyraena putnamae, were studied in the northern Persian Gulf and Oman Sea restricted to Hormuzgan province waters within 13 months period, from November 2006 up to November 2007. Biometrical and anatomical measurements were carried out, and biological surveys were conducted on 486 specimens. On the other hand, the growth and mortality parameters were estimated by using 3096 samples. These samples were collected from 3 landings, namely Bandar Abbas, Bandar Lengeh and Bandar Jask. The measurements of the minimum and maximum Fork lengths and weights were 11.7 to 8.03 cm and 135.0 to 4140.0 g, respectively. The results indicated that this species, having the Relative Length of Gut, RLG=0.34±0.002, is strongly carnivorous (often fish-eater), proven by the fact that more than 98% of its stomach contents were fish pieces. Examining the changes in the index of stomach emptiness by the percentage of CV = 0.47% indicates that this fish is Moderate feeder. The level of feeding increased in March, before spawning and decreased in June and September, simultaneously with the spawning season. There are 2 peaks of reproduction or spawning seasons during the months of April-May and September, of which the prior is assumed as the main spawning. The sex ratio (M:F) was calculated 0.5:1.0(X2 =2.11), which did not show a significant difference with expected level of 1:1 (P>0.05). The average absolute and relative reproduction rates of Sphyraena putnamae is respectively as follows: 1866827.1±255448.9 and 1097.7±94.3. The highest and the lowest diameter of matured egg are from 200 to 750 μ, and its average diameter is 402.10 ± 0.190 μ. A parameter for Saw-tooth barracuda length measurement, Lm50, based on the Fork-length, was calculated as 54.01 cm. In other words, as far as the fisheries management is concerned, the fish whose lengths are less than 54.01 cm should not be caught. The calculated level of (R2) (correlations of total length & weight), indicated strong correlations between length and weight of this fish, and the obtained formula included W =0.007100 FL 2.9295 and reinforced this assumption. The “K” Index for this fish in 3 above mentioned landings (Jask, Bandar-Abbas and Bandar-Length) were 1.24, 0.37 and 0.46 per year, respectively and the FL index for the same landings were estimated as 129, 110 and 134 cm, respectively. The growth coefficient (MONRO) for the above mentioned regions were calculated as 3.601, 3.647 and 3.917, respectively; and in the surveyed regions there were no significant differences in populations. The Total mortality coefficient (Z) was calculated 0.76, 1.12 and 1.07 per year, the Natural mortality coefficient was 0.46, 0.63 and 0.70, and the Fishing mortality coefficient (rate) (F) was found to be 0.30, 0.49 and 0.37 per year. The value of the exploitation rate (E) is equal to 0.39 per year, indicating that this species is an under-exploited resource, and there is no excessive fishing pressure on the fish supply of this species in the afore-said regions. The highest level of exploitation was found for ‘Bandar Abbas’ fishing region and the lowest level of exploitation is in ‘Bandar Lengeh’ waters.

Reproductive biology of Catla catla in the Udawalawe reservoir, Sri Lanka

The reproductive biology of Catla catla (Hamilton-Buchanan) in the Udawalawe reservoir was studied from June 2007 to December 2008. Samples of eggs from Indian major carp C. catla were collected from fish landed in the reservoir and analysed in the laboratory to assess the reproductive characteristics. C. catla. Cirrhinus mrigala, exotic Cichlids and Labeo rohita accounted for 62.2%, 21.0%, 12% and 1.0% respectively of the total landings in the Udawalawe reservoir during the study period. Gonads of C. catla were collected in the field and examined in the laboratory to determine the stage of maturity and fecundity. Data on fish length and gonad weight were collected to estimate the gonado-somatic indices (OSI). Landed catches were also examined in the field to determine the sex ratio of C. catla in the catch and was found to be 1:5.6 male to female. Results of fecundity estimates revealed that C. catla females in the Udawalwe reservoir were fully mature in June and October of the year. From the monthly variation of OSI, two recruitment pulses per year were evident. The length of the body at first maturity in female C. catla in the Udawalwe reservoir was estimated to be 74.2 cm.

The study of artificial propagation efficiency and fingerlings production of Coregonus lavaretus

In order to study of the artificial propagation efficiency in white fish (Coregonus lavaretus) and its fingerlings producing in IRAN, a 9 mounts study project was been done which during it, the characteristics of the matures and brood stocks fishes, the condition of their natural and artificial propagation, and the characteristics of produced frys, were been studied. Throughout the total 82 pieces caught fishes during September til February 2003, 10 pieces of them were the female brood stocks which during the catch time did not have spouse. The study of these fishes showed that there was no significant correlation between their weight and their length. The most and the least absolute fecundity of these brood stocks were 19120 and 11496 respectively. The artificial propagation was been done by 5 males and 4 females broods took which 57602 ova, with 89/2% fertilization rate, earned from them. The incubation period prolonged 55 days in 8°c. At the end of the incubation, 23913 larvae released. So the artificial propagation efficiency was calculated 41/51% in this study. Yolk sack absorption prolonged 4 days. 3 different food treatment were considered for fry breeding which contain of Brachiouns plicatilis as live food, salmon starter food as commercial food, and the mixed of equal amounts of live and commercial foods as third treatment. For each treatment, 3 repeat has been considered. Breeding duration prolonged 13 weeks throughout this period, different characteristics of fry were been studied weekly. The breeding results showed that there was very significant correlation between the weight and the length of frys. However the live food provided better results in growth and survival rate of frys during breeding initial 6 weeks. More ever, commercial food, in some characteristics, provided more acceptable results in comparing the live food after sixth week. The results of this study project showed that the artificial propagation in whitefish is possible in IRAN and the producing of its frys in order to restocking or introducing this species to the other Iranian suitable water resources is executable. Based on the earned information from this study, the suitable time for natural spawning of whitefish in IRAN (Amirkabir dam lake) determined between 10th January til 20th February.

Survey of exist specifications morphometric, meristic and inter species molecular genetic on Bream (Abramis brava orientalis) in Anzali wetland, southern coast of Caspian Sea, Aras Dam Lake and Azerbijan Republic

Bream (Abramis brava orientalis) is one of Cyprindae the Caspian Sea and its basin which has a special ecological, biological and economical role. Stock of this fish in the Caspian Sea has reduced during several years for different reason the over fishing, different industrial, agriculture, urban pollution and destroy of the spawning habitat. So that fishery company decided to recover the stock of this fish by the way of artificial reproduction of a Bream couple hunted from south coast of the Caspian Sea (Iran) and setting the fingerling to the rivers and inflow wetlands of the Caspian Sea.This activity has due to 20 tons Bream annual fishing in the Iranian South coast of the Caspian Sea (Gilan province coast and Anzali wetland), The artificial reproduction has decreased Bream population diversity of Caspian sea and Anzali wetland.So it has been declined to improve Braem population diversity by the entrance of Azerbijan republic Bream and encounter to the Caspian sea Bream. Meanwhile there is Bream in the Aras Dam Lake which had been forgotten by the Fishery Company of Iran .For this reason specifications morphometric, meristic and inter species Molecular Genetic have been surveyed in Anzali wetland,Southern coast of Caspian Sea ,Aras Darn Lake and Azerbijan republic during 2003-2005. According to the research on specifications of Morphometric and Meristic of Anzali wetland(120 species),Southern coast of Caspian Sea(90 species), Aras Dam Lake(110 species) and Azerbijan Republic(125 species)has Morphometric and Meristic differences. So that average weight and total length of Anzali wetland Bream respectively was 167 g and 23/76 cm, 102 g and 27/62 cm in Caspian Sea , 461 g and 3 5/38 cm in Aras Darn Lake and 3 4189 g and 15/21 cm in Azerbijan republic (We forced to use 1 year Bream of artificial reproduction in Iran). Also variation coefficient average Morphometric, Morphometric specification Ration and meristic in Anzali wetland Bream was 17/45, 21/56 and 4/63, in Caspian Sea bream 22/58, 15/27 and 3124, in Aras Dam lake Lake 17145. 1.5/27 and 3/57 and Azerbaijan republic Bream 22/29, 19/66 and 4/22. Also Bream of these four regions in general status had Morphometric significant differences based on One Way ANOVA Analysis. Meanwhile Anzali wetland Bream with Caspian Sea Bream from 41 Morphometric surveyed factors in 33 factors, with Aras Darn Lake Bream in 41 factors, with Azerbkjan republic Bream in 41 factors,Caspian Sea Bream with Aras Darn Lake Bream in 36 factors,with Azerbijan republic B ream in 40 factors and A ras Dam L ake Bream with Azerbijan republic Bream in 38 factors had significant statistical differences. These four regions Bream had differences according to the Morphomertric specification ration based on One Way ANOVA Analysis. Also Anzali wetland Bream was surveyed with Caspian Sea Bream from 37 factors i n 27 factors, Anzali wetland Bream with Aras Dam 1ake in 37 factors Anzali wetland Bream with Azerbijan republic Bream in 32 factors,Caspian sea bream with Arsa Dam Lake Bream in 26 factors, Caspian Sea Bream with Azerbijan republic Bream in 29 factors and Aras Dam Lake Bream with Azerbijan republic Bream in 34 factor had significant statistical differences. Based on Meristic factor of four regions bream in 16 surveyed factors in 10 factors had meaningful differences according to the One Way ANOVA Analysis. While Anzali wetland Bream was surveyed with Caspian Sea Bream from in 3 factors,Anzali wetland Bream with Aras Dam lake in 8 factors,Anzali wetland Bream with Azerbijan republic B ream in 6 factors,Caspian Sea bream with Arsa Dam Lake Bream in 6 factors,Caspian sea Bream with Azerbijan republic Bream in 3 factors and Aras Dam Lake Bream with Azerijan republic Bream in 8 factor had significant statistical differences.Meanwihle based on Factor Analysis and Discriminant Breams had differences. Also according to the resrarchs Anzali wetland Bream in 0+ age group till 5+ (6 age groups),Caspian Sea bream in 1+ - 5+(5 age groups),Aras Darn Lake Bream in 1+ - 7+ (7 age groups) and Azerbijan republic Bream for Morphometric and Meristic studies in 1+age group and for molecular Genetic reaserch were in 8+and 9+ age groups. According to the research 4 ecosystems Bream in status of same age, Aras lake Bream were bigger according to weight and length.Also in this research genetic diversity between four population was researched by PCR-RFLP technic on a piece of mitochondrion genome with the length of 3500bp contain of tRNA-leu,tRNA-glu,ND5/6,Cytb. Between 17 used enzyme. 4 enzyme, Dral, Bc11, Haefll and Banff showed diversity in totally 6 composite haplotype was detected. Maximum nucleotide diversity by the value% 0/58 in Azerbijan republic Bream by all haplotype. Aras darn Lake Bream had 2 haplotype and nucleotide diversity of %0/35.Anzali wetland and Caspian Sea Bream had no diversity. Statistical analysis by the usage of Monte Carlo with 1000 repeat showed significant differences between Azerbaijan Bream and other Bream(P<0/0001) but there was no significant difference between 3 regions Bream(P>0/5).

Distribution and growth biology of rock oyster Saccostrea cucullata in the Oman Sea

Distribution and growth biology of rock oyster (Saccostrea cucullata) in the northern shores of Oman sea have been struied. During this one-year study, samples have been taken monthly from ten different stations. quantity of vertical distribution of this species was obseredl in the mid - intertidal zone. After determining the spread pattern, the following subjects were studied: - Growth parameters - Distionction of the "cohorts" - Determination of "spawning Season" - Condition of the "Gonado Somatic Index" - Sex ratio - Length of the species during the first year of maturation. - Identification and determination of percentage of "Biofouler Organisms." Results obtained from the above - mentioned studies show that considering a growth factor (k) of 0.52, the value of "Loo " for this species is equal to 114 (mm).Five to six different age groups were observed among the samples taken. In the areas where this study was conducted, this species grows 24 to 30 (mm) in the first year of its life this growth rate is lower in the higher - aged grpups relative to the lewer - aged groups, so that the longest size classes grow between 4 to 6 (mm) per year. • The maxinum Value of the "Condition Index" is in the pozm area and the minimum value of it belongs to Darak and Tang areas. Along with the increase in the growth of gonads the above mentioned condition index increases gradually simultaneous with the onset of spawning. Also, study of the influence of environmental factors on the maturation process suggests that the most important factors affecting maturation and spawing are temperature and salinity. The study of GSI shows that this species has a coordinated bimodal spawing trend, with its spring peak in june and its autumn peak, being still higher than the spring peak, in september. The recruitment curve confirms the above spawning peaks with its peaks occuring after a delay of one month or maximum two months in comparison to the spawning peaks. The results of calcuation of "Sex Ratio" of this species in each area show that sex ratio is 1:1. Among the first size classes that reach maturity, nearly 67% of the samples are male and the remaining 33% are female. with the increase in the shell size, the percentage of males decreases and the percentage of females increases. , The above facts prove the protandrous nature of this species the diagram showing the sizes of the first samples which reach maturity suggests that more than 50% of the samples mature after their length exceeds 36 (mm). The shortest mature sample was found to have a length of 22(mm). After studying "Biofouler Organism" nine different invertebrate groups were indentified. Barnacles and Tunicates have the highest and lowest percentages respectively. According to zonal observations, Barnacles and polychacta do the greatest damage to this species.

Examining the possibilty of multiplication and breeding of (Schizothorav [sic] zarudnyi) in order to restoration of regional aquatics reservations of Hamoon Lake and taking its advantag [sic] for aquaculture

Schizothorax zarudnvi, is an endemic fish of east country waters. (Triple lagoons of Hamoon and relevant water resources) that in the world it is reported in this resource specially. This fish named Hamoon mahi is one of the most economically valuable species in this region. Because of the recent years droughts, Hamoon logoon has been drive since 2000. Also, semi-wells (a semi natural resource) were affected drastically by recent drought years and their volume reduced to nearly one third of their real volume and resulted in changing at growth and reproduction physiology process in Schizothorax zanidnyi, brood stocks. Beginning of this project was done from October 2003. It's field studies begun (brood catching) since November 2001 by two methods including entangling gairs and at semi wells of Sistan that (Beach seine) had maximum rate of preparing qualified brood stocks. Broods transferred to Cyprinidea reproduction work shop of Zahak and after taking primary measures they stored in to the edaphic pools. Increasing the success safety factor (coefficient) for artificial reproduction of Sthizothorax zarudnyi , identifying the appropriate tune for Hormonal acceptance (physiological preparation of broods) is needed , so this important work was done regularly by histological studies and GSI measurements since November. Highest GSI rates of females (%80.51) and highest IV stage abundance of sexual maturity (%l 00) were observed an march. On the base of this date, Hormone therapy was done on broods on march. The used hormones are as follows Hypophysis. extraction, GnRHa and Anti Dopamin at the dozes of 3-6 ml, 20-30kg and 10-15 ml per kg body weight respectively and 2-3 times from 11-12-80 they were injected. Injected broods kept in to two circumstances, flow-through (rounded pool) and stagnant systems. In stagnant system 14 and 19 individuals of female and male (Schizothorax zauiulnri) broods, respectively injected in 11th, 15111, 19th, and 24th of march 1380. Non of the injected broods in 11 and 15 and 19th march (in stagnant Condition) answered to Hormone therapy. After final injection broods had general less activity and a few of them died. Mean temperature of brood pond waters (daily) which were injected. Fluctuated between 10-25-13. 63°c but injected broods on 24th march had different characteristics. They had pale color and had few fecundity. In this stage of injection they hadn't any successful vulation. After injection, Mean daily water temperature was 15, 88-17, 54°c. In Flowing system, 13-16 individual of males and females respectively were injected on 15th, 19th, 22th and 23th march. None of injected producers on 15th and 19th march with mean daily water temperature of 10, 25-12°c were prepared for spawning but injected producers on 22nd an 23th march with mean daily water temperature of 13.5-1 rc responded about 75-100 percent. (Schizothorax zarudnyi) brood stocks were prepared for spawning after 353-428 hours/day from final injection. Diameter of obtained eggs (before fertilization) was between 1.9-2.3 min and of fertilized eggs was 3.8mm. Fertilized eggs of (Schizothorax zarudnyi) were hatched after 6-7 days with mean water temperature of 17.08°c. Mean length of on one day larvae was 9.47 mm. Larvae was 9.47 mm. Larvae adsorbed the whole yolk sac after , 5-6 days at 17- 1°c and were prepared for releasing in to edaphic pools. Because of the lack of necessary and complementary facilities in the region , they had to release them in to veniros and growing them for 8 days. At the end of 18th day , 35000 larvae (at first) released into an edaphic pond with a volume of 150m2. After growing them for one moth , mean length and weight of new hatched larvae was 29.41 mm and 1.12►r , respectively. With respect to results of this investigation , artificial reproduction of (Schizothorax zarudnyi) Can be possible at 14-17°C and flowing water with Hormonal treatment. It -s breeding has increased development than other cultural specious in the region. Due to high economical value of this specious in Sistan and ti-s specialization east waters of Iran and having high resistance and proper growth There is a need of it's development and reproduction and culture in fish culture fanns (edaphic ponds• two-purpose pools) at the region and country.