Effects of polyunsaturated fatty acids (PUFAs) on gonadal maturation and spawning of striped gourami, Colisa fasciatus

The present study was undertaken to determine the effects of polyunsaturated fatty acids (PUFAs) on histomorphological structure of liver, developmental stages of ovary, serum calcium (Ca2+) level, sperm quality and spontaneous spawning performance of striped gourami, Colisa fasciatus. Fishes were collected from the Brahmaputra River, Mymensingh, Bangladesh. Treated group was fed with supplemental diet enriched with 1 % squid extracted phospholipids for 3 months while the control group was given the same feed except phospholipids. For histomorphology of liver and ovaries, samples were collected on monthly basis. Treated group exhibited higher gonadal maturation resulted in spontaneous spawning compared to control. During spawning time, normal morphological structure of hepatocytes with lipid granules was observed in the liver of treated group, whereas less lipid granules with altered histological appearance were noticed in control group. Moreover, serum Ca2+ concentration was measured significantly higher (P<0.01) in PUFA-treated female in contrast with control one. Again, sperm quality was determined by staining the sperm with trypan blue dye. Live sperm depicted transparent appearance in contrast to the dead one that retained black spots. The amount of live sperm was significantly higher (98.86 ± 0.87 %) in PUFA-treated males than that of control (90.58 ± 0.67 %). Therefore, the present study clearly indicated these enhanced spawning performances of C. fasciatus owing to PUFAs supplementation in diet.