Effects of Time after Hormonal Stimulation on Milt Properties in Waigieu Seaperch Psammoperca waigiensis

Abstract

The objective of the present study was to assess the effects of time after stimulation with domperidone (DOM), luteinizing hormone releasing hormone analog (LHRHa), and human chorionic gonadotropin (HCG), on features of spermiation including milt physical properties, sperm motility parameters, and sperm morphology, in Waigieu seaperch Psammoperca waigiensis. Male broodfish were injected with either 0.9% saline solution (control), or a single dose of DOM [20 mg/kg body weight (BW)], LHRHa (20, 50, or 80 μg/kg BW), or HCG (500, 1000, or 1500 IU/kg BW). Milt samples were collected before hormone induction (0 h) to assess original milt condition, and at 24 h, 48 h, and 72 h post injection (p.i.). Results showed that treatment with saline solution, DOM, or LHRHa did not significantly alter milt physical properties, sperm motility parameters, or sperm morphology. Treatment with HCG at a dose of 1000 IU/kg BW significantly increased milt volume, total sperm production, and sperm motility parameters, but decreased spermatocrit and sperm concentration at 48 h p.i. These parameters were significantly reduced at 72 h p.i. In conclusion, our results suggest that Waigieu seaperch milt should be collected 48 h after hormonal stimulation with a single dose of HCG (1000 IU/kg BW) to ensure high properties of milt such as milt volume, total sperm production, and sperm motility parameters.