Induction of spawning in common carp (Cyprinus carpio) using LHRHa (D-Ser $(tBu)^6$, $Pro^9$-NEt -LHRH) combined with haloperidol: Effects of different treatment time and determination of latency period dependence on temperature

A single injection of 20$\mu$g/kg LHRHa $([D-Ser (tBu)^6, Pro^9-NEt]-LHRH)$ combined with 0.5 mg/kg of the dopamine receptor antagonist, Haloperidol (LHRHa+HAL) was used for induction of spawning in the common carp under routine hatchery conditions. This treatment caused successful ovulation. Latency in common carp injected with LHRHa+HAL was dependent on water temperature, and minimal latency was 14 h. When LHRHa+HAL was given at various hours of the day it resulted in identical spawning with the same latency. These results show that the predicting latency at a given temperature may provide successful hatchery management for fish farmers.