Hair loss in cats is invariably caused by excessive self grooming due to a generalised feeling of itchiness. These are the words of Dr Bruce Fogle in his book Complete Cat Care. I found the tip interesting and quite surprising. This is because a lot of people are looking for reasons why their cat has lost some hair but if what Dr Fogle says is to be believed, and he is very believable, then nearly every cat owner need look no further than over-grooming because of an itchy coat.
Of course, the difficult part is then deciding what is causing the itchiness. Dr Fogle also states that in cats, hormonal skin diseases are so rare as to be virtually non-existent. On that statement you can almost write off the endocrine system (glands secreting hormones) as a possible cause.
The next most obvious cause will be an allergen to which the cat is allergic and these are very difficult to diagnose. Perhaps the most common are: flea bite allergy, airborne allergens and food allergens so strict flea control, a change of environment and a change of food might be the logical steps to take. Of these, the flea bite allergen is the most common by far, I suspect. The flea bite allergy is also called flea allergy dermatitis which is a form of miliary dermatitis.
Scabs along the midline of the back and around the neck due to over grooming suggests an allergy to fleas. It is possible and perhaps likely that the single most common reason why cats are taken to veterinarians for treatment is the cat flea.
He also states that skin problems are the most common reason why cats are taken to veterinarians. Following on from the above, he says that most skin problems involve itchiness.
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