The best control comes from feeding animals a diet that does not contain synthetic toxic preservatives.
Comfrey tea can be use topically for dog skin allergies. Cook a mess of comfrey greens, dilute the cool pot liquor down to a light iced tea color and pour or dap onto the hot spots or into the into the dogís fur. Comfrey is very powerful so donít use more than once a month and only when needed. Cornmeal juice is also good and can be used more often. Put a cup of whole ground cornmeal in a 5 gallon bucket of water, strain out the solids and apply to the skin liberally.
Bathing the dogs in herbal shampoos that contain orange (d-limonene) and tea tree (melaleuca) will also help. Dry cornmeal, horticultural or whole ground cornmeal, dusted onto problem skin areas is also helpful, if the skin problems are fungal.