The olfactory capability of dogs to discriminate between different quantities of food

A previous study failed to find evidence that dogs could use olfactory cues discriminate between 1 and 5 hot dog slices presented on a single trial (Horowitz et al., Learning Motivation, 44, 207–217, 2013). In the experiments reported here, multiple trials were used test dogs’ ability olfaction choose one of two opaque containers under which larger number food items was placed. Experiment 1, chose slices. Experiments 2 3, we examined numbers varied in numerical distance ratio smaller quantities. 4 explored discrimination quantities different food, kibble. 1–3 all showed stimuli slices, but 3 revealed no effects or 4, pieces Factors allow are discussed.