STIMULATION OF SATIATION RECEPTORS: A NOVEL APPROACH TO WILDLIFE MANAGEMENT

Chemicals that reduce food intake by stimulation of satiation receptors could offer a novel, nonlethal method of reducing feeding damage to crops or stored products by vertebrate pests. Such chemicals result in a deep-seated, physiological response whose effects on feeding are unlikely to wane through habituation. We describe a preliminary evaluation of the potential for the use of satiety stimulants (i.e., feeding inhibitors) in wildlife management. Using rats (Rattus norvegicus) as the model system, we carried out trials to determine the effects of oral administration of 5 putative feeding inhibitors on food intake. We found that the most promising compounds 2-buten-4-olide (2-B40) and 5-hydroxy-L-tryptophan (5-HTP) reduced the food intake of all rats, irrespective of gender or prior feeding status. We observed the maximum reduction in food intake (53%) in hungry rats during the first hour following gavage with 5-HTP (100 mg/kg). In 2-choice feeding tests, we found 2-B40 and to a lesser extent 5-HTP, to be unpalatable to rats, hence these putative wildlife management agents may also act as feeding deterrents (repellents). We successfully identified compounds that were effective at reducing feeding in rats. Further research is required to define the range of applications for these materials in wildlife management.