بررسي برخي پارامترهاي رشد ماهي Oxynoemacheilus argyrogramma 1874 Heckel در رودخانه گاماسياب استان همدان

Investigation of some growth parameters in Oxynoemacheilus argyrogramma (Heckel,1847) from Gamasiab river (Hamaden Provience_western Iran)

ماهي Oxynoemacheilus argyrogramm يك گونه بومي غرب ايران مي­باشد كه اطلاعات بيولوژيكي اندكي در مورد اين گونه وجود دارد. در اين تحقيق الگوهاي رشد و ساختار سني گونهO. argyrogramma در رودخانه گاماسياب همدان از اسفند 89 تا خرداد 90 طي 4 ماه نمونه­برداري مورد بررسي قرار گرفت. در مجموع از 317 عدد ماهي صيد شده 147 عدد نر و134 عدد ماده بودند كه اختلاف معني­داري بين جنس نر و ماده وجود نداشت (0/05

O. argyrogrammais a species native to the west Iran. There is little information about this species. The growth pattern and age structure of O. argyrogramma have been studied in the Gamasyab river, Hamdan province .In this study, a total of 317 specimen collected from March 2011 to June 2011, including 147 males and 134 females. There was no significant difference between males and female's abundance (P<0.05), meaning the sex ratio was 1:1.09. Range of the length and weight changes in the population was 2.7-7.6 cm and 0.181-3.331 g respectively and the maximum frequency of length was observed in the range of 4.2-5.7 cm. Age determination by opecula showed that the studied population includes 4 age groups (0+ to 3+). LWR was obtained W=0.008 for males, W=0.006for females and w= for the population. The growth pattern was isometric for males, and positive allometric for female and the population. The provided information can be used in the management of species and biodiversity in future. The VBGF was Lt=10.08(1-exp-0.158(t+2.71))) and Lt=10.91(1-exp-0.176(t+2.46)) for females and males respectively. The provided information can be used in the management of species and biodiversity in future.