Effects of Clove Oil, Tricaine, and CO2 on Gamete Quality in Steelhead and White Sturgeon

Abstract

This study examined the direct impact of three commonly used anesthetics-clove oil (86% eugenol), tricaine (tricaine methanesulfonate ), and CO 2 -on egg quality for steelhead Oncorhynchus mykiss and that of clove oil and tricaine on the motility of sperm from both steelhead and white sturgeon Acipenser transmontanus. Exposure of unfertilized eggs for 6 or 24 h to 150 mg clove oil/L, 225 mg tricaine/L, or less than 100 mm Hg CO 2 resulted in no reduction in egg fertility or embryo survival to hatch. However, higher doses (1,500 mg clove oil/L; 2,250 and 22,500 mg tricaine/L; or more than 125 mm Hg CO 2 ) negatively impacted egg quality. Similarly, a 3-h exposure to clove oil (150 mg/L) or tricaine (225 mg/L) produced no significant effect on sperm motility in steelhead. White sturgeon sperm showed a modest decline in motility after incubation in clove oil. Thus, the data suggest that clove oil and tricaine can be used on fish prior to gamete harvesting without significant adverse impacts on gametes. Although CO 2 is unlikely to have deleterious effects on eggs, CO 2 -associated declines in ovarian fluid pH may be of concern when ovarian fluid pH is used as an indicator of egg quality.

Efficacy of clove oil and ethanol againstSaprolegniasp. and usability as antifungal agents during incubation of rainbow troutOncorhynchus mykiss(Walbaum) eggs

“…This indicates that high concentrations of clove oil are toxic to rainbow trout embryos before the eyed stage. Holcomb, Woolsey, Cloud and Ingermann () reported a complete lack of embryo development of O. mykiss eggs if they were bathed in 1500 mg L −1 clove oil before fertilization, but no effect was found with the clove oil concentration of 150 mg L −1 supporting our finding of clove oil toxicity at high concentrations to trout eggs. Also, for example, hydrogen peroxide treatments during blastopore formation increase rainbow trout egg mortality making the chemical better suited to use after the eyed‐egg stage (Gaikowski, Rach, Olson, Ramsay & Wolgamood ) or the concentration should be decreased during estimated blastopore formation (Barnes & Gaikowski ).…”

Motility Parameters of Rainbow Trout (Oncorhynchus mykiss) Spermatozoa in Relation to Sequential Collection of Milt, Time of Post-mortem Storage and Anesthesia

“…The latter authors did not observe changes in percentage of motility of rainbow trout sperm exposed to various concentrations of anesthetics. However, the recent study of Holcomb et al (2004) on rainbow trout sperm showed that 3 h incubation of milt with clove oil and tricaine did not alter sperm motility significantly. Further studies are necessary to determine whether anesthetics can penetrate the male reproductive system and influence sperm motility directly.…”

Tricaine methane-sulfonate (MS-222) application in fish anaesthesia

“…However, higher doses reduced egg quality. Similarly, 3 h exposure to MS-222 (225 mg l )1 ) produced no significant effect on sperm motility in steelhead trout (Holcomb et al, 2004;Zydlewski et al, 2008). While anaesthesia had no impact on egg survival, in anaesthetised males direct contact between MS-222 and sperm affected the duration of sperm motility (Wagner et al, 2002).…”