Puppies fed Vitamin A deficient diets have poor growth rates and develop defective remodelling of bone during active growth<ref name="NRC"/>, especially the bones of the cranium, which can result in [[Ear - Anatomy & Physiology#Deafness|deafness]]<ref>Mallenby E. The experimental production if deafness in young animals by diet. J Physiol 1938;94:380-398.</ref>. Adult dogs fed Vitamin A deficient diets experience '''anorexia, weight loss, squamous metaplasia of mucus secreting cells that can result in xerophthalmia (dry eye) and increased susceptibility to [[Pneumonia Overview|pneumonia]]'''<ref>Russell WC and Morris ML. Vitamin A deficiency in the dog. Experimental production of vitamin A deficient condition. JAVMA 1939;95:316-320.</ref>. Cutaneous hyperkeratosis and skin lesions are also associated with Vitamin A deficiency in adult dogs<ref>Ihrke PJ and Goldschmidt MH. Vitamin A-responsive dermatosis in the dog. JAVMA 1983;182:687-690.</ref>. Adult females fed inadequate levels of Vitamin A during gestation have an increased risk of foetal abnormalities<ref name="NRC"/>. | Puppies fed Vitamin A deficient diets have poor growth rates and develop defective remodelling of bone during active growth<ref name="NRC"/>, especially the bones of the cranium, which can result in [[Ear - Anatomy & Physiology#Deafness|deafness]]<ref>Mallenby E. The experimental production if deafness in young animals by diet. J Physiol 1938;94:380-398.</ref>. Adult dogs fed Vitamin A deficient diets experience '''anorexia, weight loss, squamous metaplasia of mucus secreting cells that can result in xerophthalmia (dry eye) and increased susceptibility to [[Pneumonia Overview|pneumonia]]'''<ref>Russell WC and Morris ML. Vitamin A deficiency in the dog. Experimental production of vitamin A deficient condition. JAVMA 1939;95:316-320.</ref>. Cutaneous hyperkeratosis and skin lesions are also associated with Vitamin A deficiency in adult dogs<ref>Ihrke PJ and Goldschmidt MH. Vitamin A-responsive dermatosis in the dog. JAVMA 1983;182:687-690.</ref>. Adult females fed inadequate levels of Vitamin A during gestation have an increased risk of foetal abnormalities<ref name="NRC"/>. |