Body composition changes in white-tailed deer fawns during winter

Abstract

1992. Body composition changes in white-tailed deer fawns during winter. Can. J. Zool. 70: 1409-1416. Sixteen white-tailed deer (Odocoileus virginianus) fawns were captured near Chicago, Illinois, between November and April, and their body composition was determined, to investigate changes in body composition and chemical component distribution as they catabolized tissues over the winter. Live weights of the fawns ranged from 16.8 to 41.6 kg (31.1 f 2.0), and ether-extractable fat concentration of the bled, ingesta-free body ranged from 2.3 to 48.9% (24.5 f 4.7) on a dry basis. Carcass, viscera, and hide contained, on average, 70, 21, and 9 % of the bled, whole body fat, respectively. Above approximately 15% whole body fat (dry basis), the percentages of whole body fat contributed by the viscera and carcass increased and decreased, respectively. Body composition (blood-, ingesta-, and fat-free basis) averaged 72% water, 23% crude protein, and 5 % ash; ash and phosphorus concentrations increased and protein concentration decreased over the winter. Sodium concentration tended to decrease. Based on relationships between chemical components and body weight, the composition of weight lost during winter was calculated to range from 12% water, 84% fat, 4 % protein, and 0.5% ash during early winter to 73 % water, 0.3 % fat, 25 % protein, and 2 % ash during early spring. Calculated metabolizable energy derived from tissue catabolism was a quadratic function of body weight and ranged from 7.7 to 1.1 Mcallkg of bled, ingesta-free weight loss during early and late periods. WATKINS, B. E., WITHAM, J. H., et ULLREY, D. E. 1992. Body composition changes in white-tailed deer fawns during winter. Can. J. Zool. 70 : 1409-1416. Seize faons du Cerf de Virginie (Odocoileus virginianus) ont Ct C captures prks de Chicago, Illinois, entre novembre et avril; les variations de leur composition corporelle et de la rdpartition de leurs composantes chimiques ont ete evaluCes au cours de l'hiver, pendant le catabolisme des tissus. La masse des faons vivants s'echelonnait entre 16,8 et 41,6 kg (3 1,l f 2,O) et la concentration de graisses solubles dans l'ether chez les faons saignes et vides de leurs ingesta se situait entre 2,3 et 48,9%(24,5 f 4,7) de la masse skche. La carcasse, les visckres et la peau contenaient, en moyenne 70, 2 1 et 9%, respectivement, de toutes les graisses contenues dans le corps saignC. Au-dessus d'une valeur d'environ 15% des graisses totales (masse skche), le pourcentage des graisses contenu dans les visckres augmentait et le pourcentage des graisses contenu dans la carcasse diminuait. La composition du corps (corps vidC du sang, de la graisse et des contenus visceraux) etait d'environ 72% d'eau, 23 % de protCines brutes et 5 % de cendre; les concentrations de cendre et de phosphore augmentaient et la concentration de proteines diminuait au cours de l'hiver. La concentration de sodium avait tendance a diminuer. D'aprks les relations entre les composantes chimiques et la masse corporelle, la composition de la masse p...

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