Alleviating calf weaning stress: the important role of maternal bovine appeasing substance in calf husbandry management.

OBJECTIVE

Weaning stress impairs calf health by causing growth retardation and immune dysfunction, underscoring the need for targeted interventions. Maternal bovine appeasing substance (MBAS) has been proposed as a novel therapy for stress in cattle, but its efficacy against weaning stress remains unclear. This study assessed the health impacts of weaning and evaluated MBAS as a potential intervention.

METHODS

Health impacts were first evaluated in 60 weaned Holstein calves. Then, another 60 healthy calves of similar age were randomly divided into two groups (n = 30/group). Control calves received a single 2.5 mL saline spray one day pre-weaning, while the MBAS group received a single 2.5 mL spray of MBAS (100 mg/mL).

RESULTS

Weaning stress increased diarrhea (56.52% to 78.26%) and respiratory disease incidence (10.17% to 15.88%), elevated exercise steps (32,196±1,267 vs 38,226±1,132, p = 0.0043), and reduced dry matter intake (2.78±0.03 vs 2.59±0.06 kg/d at D4, p = 0.0041) and average daily gain (ADG, 0.89±0.05 vs 0.71±0.04 kg/d, p = 0.0230) within 15 days post-weaning. MBAS improved ADG (0.92±0.15 vs 1.25±0.14 kg/d at D7, p = 0.0120), lowered respiratory disease (23.07% to 17.42%) and diarrhea incidence (83.70% to 52.70%), and shortened diarrhea duration (4.32±0.47 d vs 3.15±0.32 d, p = 0.0090). It also reduced serum interleukin-1 (49.39±2.40 vs 43.51±1.64 pg/mL, p = 0.0350), haptoglobin (58.29±3.3 vs 49.40±3.65 μg/mL, p = 0.0050), and cortisol (37.42±1.67 vs 33.05±2.24 nmol/L, p = 0.0310), while increasing immunoglobulin G (10.30±1.46 vs 13.50±1.58 μg/mL, p = 0.0131) and interferon-γ (6.89±0.47 vs 7.94±0.63 ng/L, p = 0.0330) on D5.

CONCLUSION

MBAS alleviates weaning stress by inhibiting inflammation, enhancing immunity, and reducing anxiety, providing an effective strategy to improve calf health.