اثر مراحل رسيدگي جنسي روي تركيب شيميايي عضله ماهي سفيد Rutilus frisii kutum Kamenskii, 1901 در خليج گرگان

Effect of maturation stages on gonadal indices and Chemical composition of gonad in Cyprnius carpio (Cyprinidae)

Changing of chemical content (lipid and protein) of gonad and gonadal indices (oocyte size, fecundity, gonadosomatic index) of male and female of {Cyprinus carpio) from Gorganrud River shied during gonad maturation, was investigated. For this purpose, 5 sampling were done during spawning migration time. In each stage oocyte size, fecundity, gonadosomatic index, lipid and protein content of maleʹs and femaleʹs gonad were measured. With nearing to spawning stage gonadosomatic index, oocyte size increased significantly (P<0.05). Significant difference wasnʹt seen in lipid and protein content of maleʹs and protein composition of femaleʹs gonad (P>0,05) but difference in lipid content of femaleʹs gonad was significant. But increasing trend was seen in gonad chemical content (lipid and protein) in both male and female.