Y. Keivany, S.s. Mortazavi , O. Farhadian ,
Volume 7, Issue 2 (Spring 2018)
Abstract
Aims: King Nase fish (Chondrostoma regium) is a benthopelagic species that lives in stagnant and current water with a temperature range of 3-21°C and in the middle and upper parts of the river. The aim of this study was to evaluate the reproductive characteristics of King Nase fish.
Materials and Methods: In this experimental study, 335 fish were randomly caught and transferred to the laboratory after anesthetization and fixation for biometric measurements and dissections. The data were analyzed by one-way analysis of variance (ANOVA), Duncan's multiple range test (MRT), and unpaired T-test and SPSS 19 software.
Findings: The fork length and weight changes in male and female fish in all age groups, except for 1 and 2 year in females, showed a significant difference. There was a significant correlation between fork length, weight, and age of fish with its fecundity (r2=0.6922; r2=0.6852; r2=0.7284). Age groups of the males and females were 1 to 5 and 1 to 6 years, respectively. The sex ratio of male to female was 1:1.3. The oocyte diameter significantly increased from April to June and decreased in July and August. Changes in oocyte diameter corresponded to gonadosomatic index. The highest gonadosomatic index in males and females was in April and June, respectively, and varied with other months (p<0.05). The mean of this index was significantly higher in females than in males. The hepatosomatic index showed a significant difference during the months of the year (p<0.05). The spawning season was from late March to June.
Conclusion: The spawning season of King Nase fish is from late March to June and has a group simultaneous spawning pattern.
Yazdan Keivany, Zahra Zahra Ghorbani-Ranjbari,
Volume 9, Issue 3 (8-2020)
Abstract
The aim of the present study was to estimate growth and mortality parameters and length-weight relationship of Barilius mesopotamicus populations in difrent Iran basins. For this purpose, 460 fish specimens from Diala, Jarrahi, Karun, Karkheh and Bushehr basins and subbasins, including Zardmashin, Aalaa, Jarrahi, Dez, Shur, Meymeh, Changooleh, Kangir, Doyrej, Ahram, Zohreh, Kheirabad, Karzin, Shahpur and Darolmizan rivers, were sampled. Total length, fork length and standard length were measured by a digital caliper (cm) and total weight by a digital scale (g). Also, some scales were prepared and studied for age determination. The length-weight relationships showed that population from Bushehr, Jarahi, Karun and Dila, had negative allomeric growth pattern while Karkheh population had an isometric growth pattern. The highest estimated total length and weight was 9.2 cm and 5.4 g. Age of the fish was between 0+ and 2+. The highest asumptetic total length was observed in Diala basin with Bertallanfy equation of Lt= 9.22[1-e-1.3(t+0.07)]. The condition factor was about 0.5. Considering body indices, Bushehr, Jarahi, Karun and Diala had a better condition, and Karkheh population had a lower index, probably indicating a poorer condition in this river.
