RESIDENT THE OHIO STATE UNIVERSITY Alexandria, Ohio, United States
Abstract: Background – Energy homeostasis is essential for survival of the bovine neonate. There is minimal information on the energy axis (glucose and insulin) and enteroinsular axis (EIA; insulin and glucagon-like peptide-1 [GLP-1]) in healthy and critically ill neonatal calves.
Hypothesis/Objectives – Characterize the EIA response to various oral formulations (cow’s milk [CM], milk replacer [MR], lactated Ringer’s solution [LRS; control] and direct nursing [DN]) in healthy, neonatal beef calves. We hypothesized calves will have a functional EIA and a more robust and prolonged response to CM and DN compared to other groups.
Animals – 26 healthy, 3-5 day-old mixed breed beef calves from a private farm.
Methods – Calves were randomly placed into four treatment groups: 500 mL CM, MR, and LRS via orogastric intubation, and DN from the dam for two minutes after one hour of fasting. Blood samples were drawn in plain and EDTA tubes frequently for 180 minutes.
Results – Increased blood glucose concentrations were noted in the DN and MR groups. Compared to baseline, serum insulin and plasma GLP-1 concentrations increased by 20% and 30%, and by 25% and 39% by 45 minutes in the MR and DN groups, respectively, with no evident changes in the other groups. The AUC for insulin and GLP-1 was not different between groups, however, they were statistically elevated in the MR and DN groups.
Conclusions and Clinical Importance – The results suggest DN and MR calves had a more robust and sustained blood glucose increase that resulted in EIA activation.
