Chu kỳ sinh sản của nghêu lụa (Paphia undulata Born, 1780) tại Khánh Hòa

Abstract

    This paper presents a result on some reproductive cycle of P. undulata through 1.440 samples collected in Khanh Hoa province in 2017. The result showed that, this clam had continuous breeding season but the peak of spawning divided into two periods from March to May and from September to October. The gonadal index of P. undulata fluctuated monthly with two peaks of May (3.21) and October (3.29). Sexual maturity was attained at 43mm for male and 44mm for female. The absolute fecundity was 852,400 ± 108,223 eggs/female in group of 37 – 42mm and 1,382,000 ± 184,136 eggs/female in group of 49 – 54mm. The relative fecundity was highest in group of 43 – 48mm (125,252 ± 17,269 eggs/g of total weight) and lowest in group of 49 – 54mm (103,723 ± 10,851 eggs/g of total weight). The real fecundity was highest in the group of 43 – 48mm (420,167 ± 153,728 eggs/spawning) and significant difference compared to group of 37 – 42mm (230,000 ± 90,111 eggs/ spawning) (p<0.05).