Selected blood chemistry and hematologic characteristics in milk-fed and conventionally fed calves

Effects of diet and age on selected blood chemistry and hematologic characteristics were studied in 20 Holstein bull calves. Milk-fed calves (treatment 1) were maintained exclusively on a milk-replacer diet. Conventionally fed calves (treatment 2) were provided a calf-starter diet and alfalfa hay beginning at 2 wk of age and were weaned from milk replacer at 7 wk of age. Blood samples were collected by jugular puncture from all animals just before the morning feeding at 6, 7, 9, and 11 wk of age. Milk-fed calves had greater glucose concentration in blood serum. Urea nitrogen of blood increased in conventionally fed calves from 6 through 11 wk and decreased in milk-fed calves. Hemoglobin concentration and packed cell volume decreased in calves receiving milk-replacer diet. Total protein and albumin concentrations were greater in the conventionally fed group. Treatment differences also existed for calcium and cholesterol concentrations and in alkaline phosphatase activity.