Essential oils have been used successfully on many different kinds of animals from kittens to 2,000-pound draft horses. Most animals are more sensitive to the effects of essential oils than humans. Adjust dosage proportionately, based on body weight. If the protocol for a human being (at about 160 lbs) calls for 3-5 drops, then a horse (at 1600 lbs) could use as much as 10 times that amount, while a dog (at 16 lbs) would need as little as one tenth that amount. Generally speaking, if you have never put oils on an animal before, you should start carefully, applying them only to the feet, paws, or hooves at first.
In the cats and small dogs, essential oils should ALWAYS be diluted before applying, because they are actually MORE sensitive to the biochemicals in the oils than humans. Be careful to avoid high phenol oils, such as oregano and thyme, on cats because they can be extremely sensitive to these stronger oils. They should be only used in high rates of dilution (90%) and the diluted oil should only be applied to the paws.General Guidelines
For small animals: (cats and small dogs) Apply 3-5 drops DILUTED (80-90%) oil mixture per application.
For larger animals: (large dogs) Apply 3-5 drops NEAT (dilute if using oils high in phenol) per application.
For large animals: (cattle and horses) Apply 20-30 drops NEAT (dilute if using oils high in phenol) per application.
Cats metabolite things very differently from dogs and other animals. Certain oils are potentially toxic to cats and could result in injury and even death, if applied incorrectly. For example, cats usually have adverse reactions to citrus products, and citrus oils are sometimes used to deter cats from frequenting an area. Also, cats are very sensitive to strong odors. A safe alternative, when in doubt, would be to mist them lightly with floral water. Consulting with a veterinarian is a good policy, before applying oils to cats for the first time.
For internal use (ingestion), essential oils can be put into a capsule and mixed with the feed. A few drops can be added to gravy on food when administering to dogs.
On large animals, the animal's bottom lip can be pulled out and (for example, in the case of a horse) 10 to 15 drops of oil put in. The animal will feel the effect quickly because capillaries in the lip will carry the oil into bloodstream immediately. For a large dog, 1 to 3 drops is sufficient. When treating animals with essential oils internally, make certain the oils used are pure and free of chemicals, solvents, and adulterants. Always seek the advice of a qualified veterinarian before allowing the animals to ingest essential oils.