Weaning as Stressor for Calf Welfare.

Area of Science:

• Veterinary Medicine
• Animal Science
• Physiology

Background:

• Weaning is a critical developmental stage for calves.
• It significantly impacts calf well-being, health, and productivity.
• Assessing weaning as a stressor is vital for livestock management.

Purpose of the Study:

• To evaluate the physiological and immunological effects of weaning in calves.
• To monitor hematological, biochemical, and immune parameters during the weaning process.
• To understand weaning's impact on calf stress response and metabolic adaptation.

Main Methods:

• Analysis of 61 calves during the weaning period.
• Collection of blood samples at multiple time points: start of weaning (T0), 3 days (T1), 7 days (T2), and 150 days of age.
• Monitoring of hematological, biochemical, and immune parameters, including cortisol, cytokines, acute-phase proteins, white blood cells, and serum electrophoresis.

Main Results:

• Weaning induced significant changes in cortisol levels, inflammatory cytokines (TNF-α, INF-γ, IL-8), and acute-phase proteins.
• Observed neutrophilia and lymphopenia indicate an adverse stress response.
• Metabolic adaptation was evident through alterations in protein, cholesterol, and triglyceride levels.
• Serum electrophoresis revealed decreased albumin and increased γ-globulins, suggesting immune maturation.

Conclusions:

• Weaning represents a major stressor for calves, eliciting both physiological and immunological responses.
• Despite the stress, weaning is essential for successful cattle breeding and productivity.
• Future research should explore genetic and environmental factors influencing weaning resilience.