Evaluation of bait flavors for potential use in oral rabies vaccine delivery to feral dogs (Canis familiaris)

Abstract

It is estimated that less than 20% of domestic dogs on tribal lands in the United States are vaccinated against rabies. One potential method to increase vaccination rates may be the distribution of oral rabies vaccines (ORV). ONRAB® is the primary ORV bait used in Canada to vaccinate striped skunks and raccoons. Research has suggested the most common non-target animals that may ingest these baits are feral domestic dogs. To further investigate the potential use of ONRAB® ORV baits to vaccinate feral domestic dogs against rabies on tribal lands, we performed a flavor preference study to increase ORV acceptance. Seven bait flavors (bacon, cheese, dog food, hazelnut, marshmallow, peanut butter and sardine) were offered in pairs to 13 domestic dogs. Each dog was offered all possible combinations of bait pairs over a period of ten days, with each bait offered six times. The proportion of times each bait was consumed first by individual dogs was calculated and comparisons among dogs were conducted. Dog food was selected first 56% of the time, and more frequently than all other bait types (F = 13.09, P = 0.0005) although bacon was close second at 54%. Marshmallow was selected first during 14% of offerings and exhibited the least preference among all bait types (F = 22.46, P < 0.0001). A more extensive evaluation is planned, preliminarily; dog food or bacon flavored ORV baits appear to be good choices for optimizing bait ingestion by feral domestic dogs.