Blood samples were collected from 80 wild deer in four areas of the southeastern United States, and from 50 captive deer on three levels of nutrition at Pennsylvania State University. Blood lipids were fractionated by thin layer chromatography; serum proteins were separated by electrophoresis on cellulose acetate strips; and proportional concentrations of lipid and protein fractions were determined by densitometry. Significant differences between seasons were found for fatty acids, lecithins, and alpha globulin in the wild deer. No tests for seasonal differences were made for captive deer. Three regression equations were developed to describe the data. The following equations were obtained by computer using the BMD-O2R packaged program. y = 35.3 - 7.0X₁ - 12.6X₂ + 1.5X₃ + 3.6X₄ + 0.3X₅ - 0.4X₆ where: y = body weight in kg. of wild deer X₁ = condition index¹ (a dummy variable) X₂ = condition index² (a dummy variable) X₃ = age in years X₄ = season¹ (a dummy variable) X₅ = polar lipids (percentage of total lipids) X₆ = cholesterol (percentage of total lipids) The multiple R² for the equation above was 0.57 y = -987.1 + 210.4X₁ - 1549X₂ where: y = mean weekly food intake by captive deer for a 2 month period prior to blood collection. (grams dry matter intake) X₁ = body weight in kg. of captive deer X₂ = season¹ (a dummy variable) The multiple R² for the second regression was 0.81. y = 50.8 - 7.3X₁ where: y = mean weekly digestible protein intake in grams by captive deer over a 2 month period prior to blood collection. X₁ = season¹ (a dummy variable) / Master of Science