Efficacy of Vaccination Against Streptococcus iniae During Artificial Spawning of the Red-Tail Black Shark (Epalzeorhynchos bicolor, fam. Cyprinidae)

摘要

Artificial spawning may precipitate high mortalities of red-tail black shark (Epalzeorhynchos bicolor) broodstock from Streptococcus iniae infection. Two vaccine formulations (aluminum or oil adjuvant) were evaluated for effectiveness. Fish (mean weight 21.2 - 5.7 g) were harvested, acclimatized, and vaccinated by intracoelomic injection. After 21 days, fish were moved to a biosecure laboratory and, one day later, simultaneously spawned and challenged by bath or by intracoelomic injection with S. iniae. Both formulations increased relative% survival (RPS) in unspawned (RPS [formulation]: 80 [aluminum]; 54 [oil]) and spawned fish (87-95 [aluminum]; 73-75 [oil]), suggesting that vaccination increases survival of red-tail black shark broodstock after spawning.