Abstract: A method of administering growth hormone includes (a) osmotically shocking aquatic animals for about 60 seconds with a hyperosmotic salt solution; and (b) placing the shocked aquatic animals in a tank containing a solution of about 300 mg/l of growth hormone (preferably bST). The treatment solution is preferably at least slightly saline. The aquatic animals are immersed in the treatment solution for between about 30 minutes and about two hours. The growth hormone solution is supersaturated with oxygen to place the aquatic animals in a state of suspended animation. Depending on the aquatic species treated, the osmotic salt solution and the treatment solution may be refrigerated. The aquatic animals are preferably treated when less than 24 hours old.