نوع مقاله : مقاله پژوهشی
نویسندگان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
This study was carried out to evaluate some biological reproductive aspects of Sillago sihama, a valuable gonochoristic species living in coastal areas of the Persian Gulf, from August 1997 to September 1998. Forty fish were caught each month, and their total length, standard length and total weight were measured. Fish were then diseeted and liver, stomach and gonads were weighted. A piece of gonad samples 01 different stages of maturity were taken and placed in bouins fixative. Minimum and maximum fish length were and 23.5 centimeters respectively. Length-weight relationship showed isometric growth in this species. Gonadosomatic index (GSI), gastrosomatic index (GI) and hepatosomatie index (HSI) were also measured. GSI was averaged 4.5 in March for females and 1.50 in April for males.
Histological evidence showed that this fish has an ovary with free riped ova at the same time and spawn once a year in spring (synchronos). Sex ratio was measured (1 M:1.2F)(α=0.05,df=1, X2=5), Size of maturity were 11.4 and 12.6cm for males and females respectively.
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