Environmental Enrichment Attenuates Acute Noise-Induced Bursal Injury in Broilers via Suppressing NF-κB and Mitochondrial Apoptotic Pathways

Abstract

Noise pollution represents a significant environmental stressor that compromises the health and welfare of farm animals. While music enrichment has been suggested to mitigate stress, the specific mechanisms by which it protects against noise-induced immune damage remain poorly understood. This study investigated whether music can mitigate acute noise-induced injury to the bursa of Fabricius in broilers. A total of 175 male Arbor Acres broilers were randomly allocated into four groups: Control (C), Noise (N), Noise plus Music (NM), and Music (M). Starting on day 14, groups N and NM were exposed to daily acute noise exposure (115–120 dB for10 min), while groups NM and M received daily 6-h Mozart’s K.448 music enrichment. We evaluated the effects of short-term (by day 21) and long-term (by day 42) music intervention. Results showed that acute noise induced significant histopathological damage, oxidative stress, and apoptosis in the bursa. While short-term music intervention showed limited efficacy, prolonged music exposure significantly attenuated these injuries. Mechanistically, music suppressed the noise-activated NF-κB signaling pathway and reduced inflammatory cytokines (IL-1β, IL-6, and TNF-α). Concurrently, it inhibited mitochondrial-dependent apoptosis by modulating Bcl-2, Bax, Cyt-C, and Caspase-3. These findings provide experimental evidence that long-term music enrichment effectively alleviates noise-induced immune injury, suggesting a practical strategy for improving poultry welfare.