2 research outputs found
Reproduction biology of Astacus leptodactylus eichwaldi in the Iranian coastal water of the Caspian Sea (Bandar Anzali)
Sampling of Astacus leptodactylusc were conducted in order to determination of biometrical and biological parameters suchas length, weight, sex ratio, fecundity and natural reproduction time. Two transect were selected at 49 34 and 49 36 geographical position on east Caspian Sea near to Anzali city. Metallic folding trap with Silurus glanis as attractive diet were used to catch Astacus leptodactylusc at each line the traps were set on depth of 35, 45, 55 and 65 (5 trap at each depth). Random sampling from each depth on tow lin for one year were conducted and the biometry performed on catched Astacus leptodactylusc where their sext uality and their ration were determined for eacd month , season and whole year. Absolute fecundity determined by cooking Astacus leptodactylusc , taking out the ovary weighing and counting them .Working fecundity assesed by separating eggs from their swiming leges while enomerate all egg . Complete randomized test of ANOVA for analysing the data were employed. The results showed average length and welght were calculated 122/07±1/74mm and 57/96±1/81gr respectively. Average absolute fecundity was 310/22 ±10/72 eggs , average working fecundity was 251/84±8/84 eggs, Average ovary weight was determined 4.31±0.619 gr and average number of eggs in one gr was 74/52±1/53 eggs. The sextual ratio in all year long was 1:1.32. The reproduction season is about seven month from Feburary to July and the moulting of males occurs two times each year. One of time is at May and the other is in September. The female molt thtina as the male start for second time
The study of establishment of rainbow trout culture and hatchery farms on Zayanderood’s River region in Caharmahal and Bakhtiyari Province
The aim of this study was to find the best location for establishment of rainbow trout culture and hatcheries farms on Zayanderood’s river region in Charmahal and Bakhtiyari province. This survey carried out over ten station along Zayanderood’s river. The result of physical and chemical analysis showd that the annual average of air temperature varied from 9.5oC - 10oC where the pH annual average value were between 7.5 and 8.8. the dissolve oxygen concentration in stations except in rainbow trout farm effluent were above 10 mg/l. the other chemical , pollutant as well as pesticides levels were under the limiting concentration for rainbow trout culture and Hatcheries activity. The plankton survey showed that the Bacillurophyta were the dominant group of phytoplankton where protozoa constituted the most abundant group of zooplankton the Benthic organisms sensitive to pollutant in particular Epirus were dominant group in all stations. In regard to fishes presence in river, five species of Ciprinidae, one species from Balitoridae and one species from salmonidae families were identified. The capacity for development of rainbow trout culture for tow phase period in Zayanderood’s river region with respect to self purification potential (self purification potential were determined from the oxidation of the effluent of the only active trout farm of the river region), minimum of 10 L/s water requirement for production of trout in concrete canal and pond system and 1 L/S water need for production in semi circular closed system were estimated to be 5202 metric tons