Drug Summary & History
LHRHa INAD 8061

The use of hormones to induce gamete maturation (ovulation and spermiation) and spawning in fishes is crucial to the success of many aquaculture and wildstock fisheries programs. Gamete maturation can be induced by a variety of hormones. However, because of its high biological activity and low species specificity, one synthetic luteinizing hormone-releasing hormone analog (LHRHa) is now a candidate for approval for the above-described use by the U.S. Food and Drug Administration.

The primary goal of field studies conducted under INAD #8061 is to generate data to help determine appropriate LHRHa treatment regimens for inducing gamete maturation in a variety of cultured and wildstock fish species. Under this INAD, Syndel International, Inc., is the sole authorized LHRHa supplier to all Investigators. Two treatment regimens are recommended (see treatment options A and B below). Disposition of investigational animals (including withdrawal times) will vary with treatment regimen.

Treatment Option A (injectable): Administer as an intraperitoneal (IP) or intramuscular (IM) injectable. Typically, IP injectables are used on females, and IM injectables are used on males. Standard dose rates are 5 - 20 ug LHRHa/kg body. Single or multiple (usually two) treatments may be administered. If two treatments are administered, the first will be the “priming” dose, and the second will be the “resolving” dose.

Treatment Option B (Pellet Implant): Pellets will be implanted in the dorsal lymphatic sinus. Dose rate must not exceed 100 ug LHRHa/kg body weight. Pellets should be administered as a single treatment, with individual fish receiving either a single pellet or two pellets. Fish treated with pellet implants may not be stocked or harvested.