Abstract
This study estimates the caloric value of red deer milk as assessed relating bomb calorimetry data with the main milk nutrients. The study also examines milk energy estimates and lactation variables to compare Iberian red deer hinds (Cervus elaphus hispanicus) and the most studied Scottish red deer (C. e. scoticus). The final model predicted energy value (E~cal~) in kcal/g of fresh milk from fat (F) and protein (P) content of milk, but not lactose: E~cal~ = 0.345 + 8.332 F + 5.403 P. Energy content per gram of milk increased with lactation stage but there was no difference between subspecies. However, subspecies differed in the daily and total energy production. Although milk energy values appeared to differ with estimates following the most used model developed from livestock, milk energy of deer estimated by both methods showed a very high correlation with each other, and both yielded also similar correlation coefficients with the remaining lactation variables. Calf gains showed a greater correlation with mean protein content and total protein yield, than with total energy yield or other milk nutrients. Milk protein appears to be more relevant to calf growth than gross energy yield. J. Exp. Zool. 300A:152–157, 2003 © 2003 Wiley‐Liss, Inc.