2 research outputs found

    Studying molecular 2 species econimic shrimps (P. merguiensis, P. indicus) Northern coast of the Persian Gulf and Oman sea using microsatelitte markers to separating and identificating of their possible populations

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    This study focuses on molecular investigation of two commercial shrimp species of penaeus family namely as : P. merguiensis and P. indicus in order to find and introduce the genetic differentiations and also probable genotypes for monitoring and managing the genetic resources of populations in three major catch areas in the Persian Gulf and the Oman Sea. Only five out of the eight primers for P. merguiensis and four out of the eight primers for P. indicus produced good amplified PCR products with fixed annealing temperature. The rest of the primers were either not easily amplified or produced nonspecific bands. Seven and six alleles were found to be unique to each of the three populations in P.merguiensis and and two populations of P. indicus respectively. Occurrences of heterozygosity deficiency were found at most loci. These heterozygosity deficiencies in observed heterozygosity in compare to expected heterozygosity may be due to inbreeding, genetic drift and consequences of illegal overharvesting of P. merguiensis and P. indicus in the studied areas as well. Deviation from HWE in both studied species was significant in most microsatellite loci (P <0.001). We observed deviation from HWE in most loci with hetrozygosity deficits. The genetic variation results showed that the pairwise Fst values were significant between populations in both species. The assignment test for P. merguiensis revealed high gene flow between Hormoz and Jask and restricted genetic flow between Guatr and Hormoz populations .We observed high gene flow between Hormoz and Jask populations for P. indicus. It seems that the changes in immigration patterns of populations between Hormoz, Jask and Guatr areas in both species are depend on the influence of Persian Gulf currents or the life cycle of studied species. Alternatively, the presence of ecological barriers such as mangrove forests may result in restricted genetic flow between Guatr and both Hormoz and Jask populations

    The Study of biology (age, feeding and, reproduction of Rutilus rutilus caspicus in south coast of the Caspian Sea (Iranian waters)

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    The Caspian Sea is an important source of water in terms of having valuable resources of sturgeon and bony fish is taken into consideration roach(Rutilus rutilus caspicus (L.)) is one of the most important commercial species in the southern coast of the Caspian Sea in Iran , the catch of this species has declined substantially in the last 10 years, The management and exploitation need of comprehensive review of its biology .This study as part of a comprehensive study of feeding , spawning and growth of this species.In this study, using samples caught in beach seine along the southern coast of the Caspian Sea coastal ( Iranian waters ) took place. The fork length and total weight ranged between 12.5 to29.5(cm) and 29 to293( grm),10.5 to23(cm) and17.2 to21(grm) in Golestan and Gilan Province respectively. The b value of the length-weight relationship ranged 3.02 to 3.25 and 3.28 to 3.75 for female and male, in Golestan and Gilan Province respectively. The age composition of the catch was from 1 to 4 year in both Province, there was one spawning peak and Fecundity variations were high and ranged 7260 to 231965 eggs. Average growth in length was described with the Von Bertalanffy growth model: L (t) = 30.94(1-exp (0.42(t-0.18) and L (t) = 20.49(1-exp (0.53(t-1). The percent of empty stomach and prey dominant evaluated during different seasons by specific formula. Result showed that gastropod, Polychaete worms and molluscs were dominated and specific food items respectively. Shrimp, fish, insects, zooplankton and clams were scare of prey
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