Fertilization by refrigerator stored sperm of the Indian major carp, L abeo calbasu ( H amilton, 1822)

This study reports on the spermatological properties, and on the development of a protocol for refrigerator storage (4°C) of L abeo calbasu ( H amilton, 1822) sperm for artificial breeding. Volume, motility, concentration and pH of the freshly collected sperm were 2.21 ± 0.53 (μL g −1 of fish weight) (mean ±  SD ), 95 ± 1 (%), 1.93 ± 0.44 × 10 9 (cells mL −1 ) and 7.56 ± 0.17 respectively. Sperm activation was evaluated at different osmolalities of NaCl solution, and motility ceased completely when osmolality of the extender was ≥287 mOsmol kg −1 . Sperm retained motility for 24, 72 and 108 h, after refrigerator storage when sperm were undiluted, suspended in A lsever's solution and suspended in A lsever's solution containing 5% methanol respectively. Fertilization rate of fresh eggs with sperm stored at 4°C in A lsever's solution and A lsever's solution containing 5% methanol was 77% and 60% with a hatching rate of 60% and 43% respectively. The fertilization and hatching success of the stored sperm suggests potential to use refrigeration for transporting genetic material to hatcheries for artificial breeding of L . calbasu in B angladesh.