Some comparative aspects of milk from four species of bears
Jenness RR, Erickson AW, Craighead JJ. 1972. Some comparative aspects of milk from four species of bears. Journal of Mammalogy. 53(1):34-47
Milk specimens obtained from 26 individual bears representing Ursus americanus, U. maritimus, three subspecies of U. arctos, and Helarctos malayanus were analyzed for gross composition and were characterized for carbohydrates, fats, and proteins. Bear milks contain high concentrations of fat, proteins, and minerals, but are low in carbohydrates. The lactose content of milk from bears maintained in zoos was much higher than that from wild bears. Myo-inositol was identified as a prominent constituent. The principal fatty acids are palmitic ( C16: 0) and oleic ( C18: 1). Polar bear milk fat, however, has significant concentrations of palmitoleic ( C16: 1) and long chain fatty acids, probably derived from food fat. The caseins of bear milk consist of two principal groups of proteins readily separable by gel electrophoresis. The whey proteins contain five groups of proteins not found in blood. These exhibit evidence of great species specificity and, in some cases, of genetic polymorphism within species.
- Type
- Journal Article
- Authors
- Jenness, R; Erickson, Albert; Craighead, John
- Units
- YELL
- Keywords
- Animal Studies, Bears (Ursidae), Mammals, Nutrients