Bahman Cheperli; Rahman Patimar; Rasoul Ghorbani; Kiavash Golzarianpour
Abstract
To study reproductive characteristics of Caucasian dwarf goby (K. caucasica), a total of 149 samples were caught in the Gorgan bay and 192 inthe Gomishanwetlandusing beach seine during a period from February 2014 to May 2016.Thereproductive characteristics including sex ratio, gonadal development index, ...
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To study reproductive characteristics of Caucasian dwarf goby (K. caucasica), a total of 149 samples were caught in the Gorgan bay and 192 inthe Gomishanwetlandusing beach seine during a period from February 2014 to May 2016.Thereproductive characteristics including sex ratio, gonadal development index, and absolute fecundity, relative fecundity were calculated.Samples of Gorgan bay ranged from 8.07 to 39.41 mm TL and 0.01 to 0.84 g total weight, while the samples caught in Gomishan wetland had total lengthlength between 15.48 to 44.78 mm and in the total weight between 0.05 to 1.10g.The highest condition factor in the Gorgan bay for both sexes was observed in February and March, and in the Gomishan wetland for in January and April. In the both study areas, the highest average GSIof females was observed in March and of malesin April. Minimum, maximum and average ofabsolute fecundity were 79.80, 888 and 387,37in the Gorgan bay respectively, and the relative fecundity were 152.58, 2733.54 and 797.11 respectively. While absolute fecundities’ minimum, maximum and averagewere 136.96,1002.22 and 482.94 and those of relative fecundity 243.70,2326.53 and 870.32. Ova diameter ranged between 0.24 to 0.84 mm with a mean value of 0.52 mm, and in the Gomishan wetland mean of the diameter was 0.50 mm ranging from 0.26 to 0.85 mm. Analysis of GSI revealed that the species spawns once per year in a short period, and has different eggs during this period.
Ashraf Jazayeri; Fahimeh saberi; Tayebeh mohammadi
Abstract
Abstract
Skeletocronology is a reliable method for estimating the age but in amphibians little researches have been done in this field. In the present study, for the first time in the country of Iran, the age structure of the population, growth pattern and reproductive primary age were studied in the ...
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Abstract
Skeletocronology is a reliable method for estimating the age but in amphibians little researches have been done in this field. In the present study, for the first time in the country of Iran, the age structure of the population, growth pattern and reproductive primary age were studied in the populations of marsh frog in the northern and southern regions of Khuzestan province. For this purpose, 20 female and male marsh frog samples were fished alive in the Khuzestan province and transferred to the laboratory. After biometric studies, the specimens were prepared and after the removal of the bones of the limbs, bone samples were passaged as routine histotechnique. The number of growth stop lines and samples age were determined. In order to determine the relationship between age and body weight, body length and age with eye lens weight, the data was analyzed statistically. the maximum number of loops counted in this population is . The adult age of males of northern and southern, males of the northern and males of the southern regions was determined 2,2 and 3 years respectively. with increasing age of females, the co-integration rate of females was reduced which is explainable by the reduction in bioavailability due to the increase in biological age. According to the results, there was a significant correlation between age of animals with body and eye lens weight, but there was no significant correlation between age of animals with body length, except a limited number of males in northern regions (P<0.05) There was.
Seyed Mehdi Amininasab; Seyed Masoud Hosseini-Moosavi; Seyed Hossein Khazaei
Abstract
Abstract
The current study carried out on the reproductive biology and breeding success of Crowned Night Heron Nyctiocorax nyctiocorax in Ali-Siyah island in Karoon River during 2007-2008. During the study, 30 nests were selected randomly using visits by boats. The reproductive phenology of Crowned ...
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Abstract
The current study carried out on the reproductive biology and breeding success of Crowned Night Heron Nyctiocorax nyctiocorax in Ali-Siyah island in Karoon River during 2007-2008. During the study, 30 nests were selected randomly using visits by boats. The reproductive phenology of Crowned Night Heron was started with the behaviour of nest building in March 22 and finished with last fledglings in June 19. From 91 eggs in 30 randomly selected nests, 3.03 eggs were found and the clutch size was varied from 2 to 5 eggs. The mean of breeding success in hatching, nestling and post-nestling breeding stages were 63.73% (n=58), 49.45% (n=45), 45.05% (n=41), respectively. The total breeding success during the breeding season was measured 52.74%. Clutch size, brood size and nest parameters did non-significant effects on the breeding success. Most mortality rate occurred before the hatching stage (36.26% (n=33)) mostly due to the natural factors.
