. The physiology of domestic animals ... Physiology, Comparative; Veterinary physiology. DIGESTION IN THE MOUTH. 283 The diastatic power of the submaxillary saliva varies very con- siderably in different animals. It is active in all the herbivora, with the exception of the rabbit and guinea-pig. In the sheep the submaxillary saliva is more active than that of the parotid, while it is faintly active in the horse, and is almost inactive in the dog when freshly secreted. The general characteristics of the submaxillary saliva vary in different animals under different conditions, and are therefore
. The physiology of domestic animals ... Physiology, Comparative; Veterinary physiology. DIGESTION IN THE MOUTH. 283 The diastatic power of the submaxillary saliva varies very con- siderably in different animals. It is active in all the herbivora, with the exception of the rabbit and guinea-pig. In the sheep the submaxillary saliva is more active than that of the parotid, while it is faintly active in the horse, and is almost inactive in the dog when freshly secreted. The general characteristics of the submaxillary saliva vary in different animals under different conditions, and are therefore subject to much con- tradiction. The secretion reaches its excess during mastication follow- ing prehension of food. It is suspended entirely during the mastication of rumination (Colin, Ellenberger, and Hofmeister),—a fact which is very remarkable when it is recollected that the chemical stimulation of the nerves of taste must be then much more marked than in the hurried first mastication. The submaxillary glands are also nearly quiescent in the intervals of rumination ; its secretion is called forth by pilocarpine injections, but to a less degree than in the case of the parotid. It seems almost incomprehensible that the submaxillary, which during rumination remains quiescent, should secrete actively during the. B Fig. 118.—Sublingual Gland of the Ox. (Colin.) A, submaxillary duct; B, inferior duet of the sublingual gland; C C, superior sublingual ducts. mastication of a tasteless foreign body, such as a piece of string or wood (Ellenberger). This fact can scarcely be explained but by supposing that the products of fermentation occurring in the rumen exert an in- hibitory influence on the secretory nerves of the submaxillary glands. Its principal function seems to be to assist in the appreciation of the sense of taste, and to act as a lubricant to aid in the first deglutition. 3. The Sublingual Secretion.—The collection of pure sublingual saliva is accomplished in the sa
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