A comparative study was made of the salivary glands of six animals with diverse diet and food habits. These consisted of the following species: coyote, bobcat, opossum, kangaroo rat, cow and goat. Correlations were sought between the food habits of the animals and the relative size and microscopic structure of their glands.
After recording the gross weights of the animal and the removed glands, microscopic sections were prepared by the paraffin method. Tissues were stained by routine and special stains, including stains specific for mucins.
The cytology of the different glands and the varied mucin reactions are described. Special attention is given to certain anatomical features noted in this study which are not clearly described in the literature, such as the presence of intercellular canaliculi which may be generally present between mucous cells; and the unique arrangement of the intercalated duct system of the submandibular gland of the kangaroo rat.
The proportion of body weight made up by the salivary glands varies in these species inversely with total body weight. This may he related principally to surface-volume ratios and variations of metabolic rate rather than the type of diet.
The weight relationships of the individual glands are correlated more closely with the manner of eating than with the type of diet, particularly in the purely carnivorous or purely herbivorous animals. Failure of the weight ratios of different groups to conform to a linear distribution suggests other factors such as modifications of physiological functions and differences in secretory rates.
Study of the microscopic structure of the glands seems to reveal greater similarity among animals with close phylogenetic relationships than among animals with similar diets. The possibility that all secretory cells within a gland are of a single basic type is suggested and discussed.
Richard M. Ritland
U. D. Register
Guy M. Hunt
Robert L. Schultz
Walter H. B. Roberts
Master of Science (MS)
Year Degree Awarded
Date (Title Page)
Library of Congress/MESH Subject Headings
Salivary Glands; Food Habits
Loma Linda University Libraries
This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.
Dalgleish, Arthur E., "A Comparative Study of the Salivary Glands of Certain Animals with Widely Diverse Food Habits" (1959). Loma Linda University Electronic Theses, Dissertations & Projects. 1365.
Loma Linda University Electronic Theses and Dissertations
Loma Linda University. Del E. Webb Memorial Library. University Archives