Carbohydrate, Enzyme, and Hematology Dynamics in Newborn Calves

Abstract The dynamics of 25 blood constituents in newborn calves were monitored. Eight calves were immediately removed from dams following birth. Jugular blood samples for carbohydrate determinations were taken at birth (within 2min), 1, 3, 6, 8, 12, 18, and 24h and every 12h until 144h of age. Samples for blood chemistries were taken at birth, 1, 3, 6, 12, 24, 48, 72, 120, and 144h. Colostrum was first fed at either 1h (group 1) or 12h (group 2) of age. At birth, plasma glucose concentrations were lower than the plasma fructose in both groups. Plasma glucose increased substantially from birth to 24h, whereas fructose decreased to nondetectable concentrations by 18h. Increases in insulin were associated with time of first feeding. Serum cortisol decreased rapidly from birth to 3h for group 1 and at 15h for group 2. Colostrum intake resulted in increased activities of serum alkaline phosphatase, gamma-glutamyl transpeptidase, and glutamic oxaloacetic trans-aminase at 6h for group 1 and at 15h for group 2. Activities of these enzymes decreased to "normal" values after 24-h samplings for group 1. Serum glutamic pyruvic transaminase and lactate dehydrogenase increased gradually in activity over the first 24h in both groups and decreased after 24h for group 1. Triglycerides and cholesterol increased from birth to 24h in both groups and continued to increase in group 1 until 144h. Creatinine decreased and bilirubin increased from birth to 24h in both groups. These changes indicated that the newborn calves were undergoing many adaptive changes in relation to either maintenance of homeostasis or nutrient intake.