All these options are non-psychoactive and contain less than 0.3% THC. Full-spectrum CBD has the greatest number of cannabinoids and terpenes making it the strongest contender of the three. However, it does have the strongest, grassy taste that some pets may be averse to. Broad spectrum CBD is less potent but has less of that grassy taste. Isolate has 0% plant matter and 0% THC. This makes it completely flavourless.