Abstract: The present application discloses a novel mammalian livestock feed additive containing a selective avian taste aversive agent, preferably dimethyl anthranilate, which is at least partially entrapped in an edible solid vehicle to improve its taste persistency. In the preferred embodiment, the edible vehicle is a modified food starch which is spray dried with the avian taste aversive agent. The disclosed livestock feed additive may be incorporated in a livestock feed to reduce the amount of feed lost to avian species, and to reduce the likelihood that mammals will be infected by avian transmitted diseases such as transmissible gastroenteritis. Alternatively, a mammalian poison is disclosed comprising an avian taste aversive additive which will increase the amount of that poison available for ingestion by mammalian target species and decrease the likelihood of secondary poisoning of a number of endangered species.