This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
I need but devote little space to a discussion of what every one already knows; namely, that the sick animal refuses all food. The farmer knows that his "foundered" horse will not eat--is "off his feed," as he expresses it. The sick cat, dog, cow or other animal refuses food. Animals will abstain from food when sick for days and weeks, refusing all food that may be offered them until they are well.
Dr. Felix Oswald says: "Serious sickness prompts all animals to fast. Wounded deer will retire to some secluded den and starve for weeks together." Dr. Erwin Liek, endorses fasting and observes that "small children and animals, guided by an infallible instinct, limit to the utmost their intake of food if they are sick or injured."
Arthur Brisbane disapproved of fasting and took Mr. Sinclair to task for advocating it. After a lengthy correspondence about the matter, Mr. Brisbane acknowledged that "even dogs fast when they are ill." Sinclair retorted, "I look forward to the time when human beings may be as wise as dogs."
A dog or cat, if sick or wounded, will crawl under the wood shed or retire to some other secluded spot and rest and fast until well. Occasionally he will come out for water. These animals will, when wounded or sick, persistently refuse the most tempting food when offered to them. Physical and physiological rest and water are their remedies.
A sick cow or horse will also refuse food. The author has seen this in many hundreds of cases. In fact, all nature obeys this instinct. Thus does nature teach us that the way to feed in acute "disease" is not to do it.
Domestic cattle may often be found suffering from some chronic "disease." Such animals invariably consume less food than the normal animal. Every stockman knows that when a cow, or horse, or hog, or sheep, etc., persistently refuses food, or day after day consumes much less than normally, there is something wrong with that animal.