Raceway Spawning of Florida Largemouth Bass: Effects of Acclimation Time and Hormone Treatment on Spawning Success

Abstract

Abstract Several acclimation periods and hormone treatments were tried to determine their effects on controlled spawning of 2-year-old Florida largemouth bass (Micropterus salmoides floridanus). During the first season, fish were acclimated to raceways for 0–8 weeks before spawning; males and females were separated during acclimation. There was an inverse relationship between the length of the acclimation period and latency of first spawn after the sexes were mixed. The longest acclimation periods resulted in the shortest latencies; however, once spawning began, the rate of spawning (interval between spawns) was similar across treatments. During the second season, unacclimated and 2-week-acclimated largemouth bass were injected with saline, human chorionic gonadotropin (HCG; 4,000 IU/kg body weight) or [D-ala6pro9-N-ethylamide]-luteinizing hormone releasing hormone (LHRH-A; 0.5 mg/kg body weight). Injections of HCG induced spawning quicker, and produced more spawns and fry, than injections of LHRH-A or sa...