Sana Sharifian, Ehsan Kamrani, Salim Sharifian,
Volume 7, Issue 3 (11-2015)
Abstract
The aim of this research was determining of gonad maturation stages during oogenesis cycle in the freshwater crab )Sodhiana iranica(. A total of 25 female crabs were collected from a fresh water spring Eelood located in 25 km in Bastak city, Hormozgan province, southern Iran from April to July 2013. Matured females were anesthetized using cooling technique and then their ovaries were removed, fixed in Bouin's fluid and dehydrated with ascending alcoholic series, cleared in xylene and then embedded in paraffin. The tissue sections were provided in 5-7 μm thickness, and stained with Hematoxylin- Eosin technique. Statistical analysis was carried out using One-way ANOVA at significance level α=0.05. An H-shaped ovary consisting of a pair of ovarian sacs was located in the cephalothorax on the dorsal side of the stomach. Based on the microscopic observations, stage of oogenesis were classified into four phases: 1) Differentiating phase Including oogonia and Primary oocyte, 2) previtellogenic phase including previtellogenic oocyte, 3) vitellogenic phase including primary vitellogenic oocyte, secondary vitellogenic oocyte and tertiary vitellogenic oocyte and, 4) mature phase including mature egg. During the oogenesis in crab Sodhiana iranica, the size of oocyte increased, the wall thickness reduced and its yolk content increased.
Hadise Kashiri, Ali Rezamand,
Volume 12, Issue 3 (10-2020)
Abstract
Alburnoides nicolausi is one of the freshwater, benthopelagic species with high ecological importance. This fish is native to Iran and found in the basin Tigris. Considering the lack of information on population genetics of A. nicolausi, the genetic diversity and structure of this valuable species was studied in the present research. For this, A. nicolausi samples were collected from Joushan and Houzian rivers, Lorestan Province, during the winter 2018 and assessed by STRs. The results indicated that A. nicolausi has a proper level of allelic diversity (the allelic mean: 8.16) and heterozygosity (the average observed heterozygosity: 0.958) in the studied regions. In comparing populations, no significant difference in allelic diversity and heterozygosity was observed between the samples (P>0.05). In studying the Hardy-Weinberg equilibrium, there was a significant deviation from the equilibrium in two cases which were in the equilibrium after sequential Bonferoni correction. Results from the analysis of molecular variance also indicated that the main part of the observed diversity was within populations. The FST and Rst values, as the indices of the genetic differentiation, were 0.062 and 0.086, respectively. In this regard, the effective migration index between the studied samples was at a relatively low level. From a total of 68 observed alleles, a considerable number of private alleles were in the populations (17 and 21 alleles for Joushan and Hozian, respectively). Altogether, it seems that A. nicolausi has a proper level of genetic diversity and the studied populations are probably separated from each other. The data from the present study could be efficient to establish the programs for management and conservation of the native freshwater stocks.
