REFRIGERATED STORAGE OF CHANNEL CATFISH SPERM

Refrigerated storage of sperm is useful for genetic study and artifici al breeding of fishes. Due to the potential loss of donor males, stora ge is important in species such as channel catfish Ictalurus punctatus from which sperm cannot be stripped. This study addresses short-term storage (at 4 C) of channel catfish sperm by evaluation of storage met hods employed for other species and for cryopreservation of channel ca tfish sperm. The objectives were to evaluate: 1) storage of intact tes tes and storage of sperm suspended in an extender solution; 2) use of various storage containers with and without supplemental oxygen; 3) us e of extender solution with and without the addition of an antibiotic/ antimycotic cocktail; 4) use of extender solution with and without the addition of methanol; and 5) use of extender solution with and withou t the addition of glucose and methanol. Sperm suspended in extender so lution retained motility significantly longer (9 d) than did sperm in intact testis (2 d). Sperm stored in Zip-loc(R) plastic bags inflated with pure oxygen retained motility significantly longer (12 d) than di d sperm stored in Zip-loc(R) plastic bags without supplemental oxygen (7 d), or sperm stored in plastic beakers (8 d) or test tubes (8 d) wi thout supplemental oxygen. Sperm stored with the addition of antibioti c/antimycotic cocktail or methanol retained motility significantly lon ger (10-12 d) than did sperm stored without additives (6-8 d). Sperm s tored in extender solution without glucose retained motility significa ntly longer (19-21 d) than did sperm stored in extender with glucose ( 13-16 d). Motility was retained for as long as 21 d in sperm stored in extender solution with 5% methanol and without glucose. In each exper iment, loss of motility was associated with bacterial growth.