The gross anatomy,cellular structure,and fatty acid composition of adipose tissue in captive polar bears (Ursus maritimus)

The gross anatomy, microscopic structure, and fatty acid composition of adipose tissue in four elderly polar bears (Ursus maritimus), that had each been in captivity for more than 24 years, were compared with that of young wild specimens. Total dissections were performed on two specimens. In both, the proportion of adipose tissue in the body was similar to that of younger wild bears, but the total adipocyte complement was smaller than that of the wild bears in one specimen, and within the normal range in the other. There was proportionately more intra-abdominal adipose tissue, particularly in the inner ventral wall of abdomen depot, in which the number of adipocytes was substantially greater than expected. The fatty acid composition of the triacylglycerols differed substantially from that of the wild bears, reflecting their diet of fish, domesticated herbivores, bread, and fruit, but there were also significant differences between cage-mates eating similar diets. © 1993 Wiley-Liss, Inc.