Study tracks immune and metabolic stress in weaned calves
Researchers monitored 61 alpine beef calves to measure physiological changes during weaning. The study found a brief but measurable surge in stress hormones, along with immune and metabolic shifts, influenced by calf sex and dam proximity. The findings may help producers make decisions about weaning timing and handling.
The trial followed 61 alpine beef calves from two Valdostana types. Blood samples were taken when weaning began at 130–135 days, then three and seven days afterward, and again at 150 days. Results showed a short, sharp stress reaction, with cortisol and sympathetic nervous system markers rising. Sex and how near the dam stayed shaped the response.
Immune and inflammatory changes also appeared. White blood cell balance shifted, with more neutrophils and fewer lymphocytes, while acute-phase proteins such as serum amyloid A and C-reactive protein changed. Inflammatory signaling molecules, especially IFN-γ, increased sharply—more than threefold one day after weaning—suggesting systemic inflammation. These effects can last over a week in cattle.
Producers may use findings to adjust weaning timing and handling, potentially reducing illness and treatment costs. Calves could benefit from lower stress and better immune outcomes. Consumers might see indirect effects through animal welfare and food supply stability, though impacts depend on farm adoption and further research. Veterinarians and livestock managers may refine protocols.