Lactation, hibernation, and mass dynamics of American black bears and grizzly bears

摘要: Milk composition and intake, cub growth, mass loss of hibernating lactating nonlactating American black bears (Ursus americanus) grizzly arctos horribilis) were investigated. Except for ash content, milk was similar between species. Lipid content varied only slightly throughout lactation, whereas carbohydrate increased from 1 to 3% during hibernation before decreasing less than 0.5% at the end lactation. Protein dry matter 6.6 ± 0.4 29.8 ± 3.9% 13.7 ± 1.1 34.4 ± 3.7% post hibernation, respectively. The bear 1% 2% after den emergence, but (1.3 ± 0.1%) did not fluctuate. Mean intake growth 185 ± 89 49 ± 9 g/day cubs 353 ± 54 98 ± 22 g/day cubs, respectively, which accounted about 9% estimated yearly consumption ...