STUDIES ON INORGANIC SALT METABOLISM

V. THE EFFECT OF FAULTY DIET ON THE DENTITION OF BROOD BITCHES, AND THE DENTAL AND SKELETAL DEVELOPMENT OF THEIR OFFSPRING

¹ Department of Pediatrics, University of California Medical School, San Francisco, California

1. Observations were made on six brood bitches and thirty-eight new-born puppies. Mothers and offspring were divided into two groups. In Group I were four large mongrel bitches, each of which had previously given birth to two or more litters, and twenty new-born puppies. The bitches and the male with which they were mated were subsequently fed quantitatively a diet of bread, lean beef, and potato. Two of the bitches were given in addition increasing amounts of sodium carbonate. All of the animals lived under identical hygienic conditions, and received a negligible amount of ultraviolet radiation.

In Group II were two bitches and eighteen new-born puppies. Eight of the latter were representatives of litters born to two bitches whose histories and dental conditions were unknown. The remainder were offspring of two bitches, one of which had been in the kennels for six weeks, and the other one year, before the birth of their young. Their hygiene was the same as that of the animals in Group I. The diet consisted of bread and meat exclusively.

2. New-born puppies of the same litters in both groups (I and II, above) showed marked differences in weight, general well-being, body ash, and structure and mineral content of the bones. Findings in general for the two groups of mothers and offspring showed certain well-defined similarities and differences.

3. The bitches in Group I, which received sodium carbonate, were not successfully bred. Dental tissue excised after they had been on the alkaline diet for one hundred and thirty days showed profound degeneration of the alveolar bone and roots of the teeth.

4. Two bitches, fed quantitatively on bread, lean beef, and potato before and during pregnancy, had convulsions during gestation and died at the time of littering. The physical condition of both animals appeared to be excellent. Their oral conditions and metabolism differed, the latter being indicated by a difference of 34 per cent in the mineral content of their offspring, although their food intakes were exactly the same and the total weights of their young differed by only 35 grams. Physical, blood, and urine findings during pregnancy were well within the normal range. Dental tissue excised post-mortem showed degenerative changes in the roots of the teeth and alveolar bone, but the degree of involvement differed in the two animals. The diet had no effect upon the number of individuals in the litters, but the puppies were small and poorly nourished, and the total weights markedly less than those for the preceding litters. The percentage of ash in the intact bones of the offspring of one mother varied from 7.8 to 10.4 per cent, with an average of 9.4 per cent. The mineral contents of the fresh body-substance of the two litters were 1.73 and 2.09 per cent. Histologic findings in both bone and dental tissues were markedly different, in certain respects, from those observed for the puppies in Group II.

5. Chemical and histologic findings on two puppies in a litter of eight in Group II were arbitrarily adopted as "normal." The mother's early history was unknown. During the last six weeks of gestation she was fed on bread and meat. Surviving members of the litter showed no clinical or x-ray evidence of rickets at the time of weaning. The fresh intact bone of the new-born puppies contained 14.2 and 14.7 per cent of ash. Histologic findings on bone and dental tissues in the two puppies were comparable, and are described.

6. The substitution of bread and meat for a vegetable, raw-milk diet, and of restricted living quarters (with a negligible amount of ultraviolet radiation) for the freedom of a ranch and an abundance of sunshine, apparently arrested an active degenerative process in the alveolar bone of a bitch. Concomitantly, the crowns of the teeth suffered disintegration. A litter born twelve months after the bread and meat diet was instituted had an average of 14.06 per cent of bone ash, the values ranging from 11.1 to 16.1 per cent. The physical condition of the puppies was extremely poor and that of the mother excellent. Histologic findings on bone and dental tissues differed in certain respects, in the various individuals, but on the whole were comparable with those arbitrarily chosen as normal.

7. Alveolar bone from three bitches, two in Group I and one in Group II, that was obtained immediately after the birth of the litters, presented a histologic picture not commonly observed. The mineral constituents of the compact bone and the cementum of the teeth appeared to have been leached out, leaving the corpuscles in various stages of degeneration in a matrix of fibers. The condition was not observed in biopsy tissue excised twelve months previously from one of the animals, nor in the post-mortem tissue from the two bitches in Group I that were given sodium carbonate, and not successfully bred.

8. The experiments are preliminary and not sufficiently numerous to warrant deductions in regard to foetal calcification. They show, however, that different combinations of common food stuffs, in the absence of ultraviolet radiation, exert markedly different effects upon the dentition of brood bitches, and upon the dental and skeletal development of their offspring.

Note:

The writer wishes to acknowledge, and to express appreciation for, the assistance of Dr. Zera Bolin of the Department of Pathology, University of California Medical School, in examining tissues and interpreting histologic findings.