Kira Nightingale
Advisor: Dr. Peter Fong

Cannabinoid (CB1) receptors are found throughout the brain, and stimulation of these receptors has been shown to increase feeding behavior in mammals and even invertebrates such as hydra, which have no central nervous system. The receptors can be stimulated via endogenous cannabinoids in the brain or by exposure to synthetic agonists. While many papers have been published on the effects of cannabinoids on mammals, very few have been published on the effects on lower vertebrates. Largemouth bass (Micropterus salmoides) are important predators in freshwater environments and are the most popular sport fish in the United States, supporting a multi-million dollar sport fishery. An increase in feeding and growth in bass farms would be extremely beneficial. While previous studies at Gettysburg College did not show any significant difference in feeding behavior, we felt that further experimentation, using a change in protocol, was necessary. Largemouth bass were administered 0.2 mg/kg Win55, 212-2 (a CB1 receptor agonist) and the mass of food consumed in a 15 minute period was measured before and after drug administration. A total of 7 replicate experiments were conducted. In 6 out of the 7 replicates, Win55, 212-2 significantly increased food intake (p=0.047-0.0015). The use of cannabinoids as feeding stimulants for largemouth bass and other farm fishes is considered.