Modulating the thermo-immuno-endocrine axis to alleviate heat stress in poultry: A pharmacological perspective.

Abstract

Rising global temperatures, compounded by diminishing water resources, have escalated the incidence and severity of heat stress in poultry production, posing a critical threat to animal welfare, productivity, and food security. Heat stress represents a multifactorial physiological challenge, disrupting the thermo-immuno-endocrine axis and thereby impairing hypothalamic thermoregulation, suppressing immune responses, and altering endocrine signaling pathways. Such imbalances contribute to reduced feed intake, compromised growth and reproductive performance, elevated mortality rates, and heightened disease susceptibility. Central to this response is the hypothalamus, particularly the preoptic area and the hypothalamic-pituitary-adrenal axis, which integrates environmental and internal stress cues to regulate corticosterone release, thyroid hormone activity, and immunological cascades. This review consolidates current evidence on the pathophysiological impacts of heat stress on poultry, with emphasis on oxidative stress, cytokine imbalance, and lymphoid tissue degeneration. It also explores pharmacological strategies for heat stress mitigation e.g., nonsteroidal anti-inflammatory drugs (NSAIDs), antioxidant supplementation (vitamins C, E, selenium), and bioactive plant-derived compounds (e.g., ashwagandha, betaine, resveratrol, curcumin). These interventions demonstrate potential in restoring cellular homeostasis, modulating endocrine activity, and enhancing immune resilience; however, their efficacy is contingent upon dosage, duration, and production context. Moreover, concerns remain regarding drug residues, side effects, and variability in responses across poultry strains. In parallel, the integration of precision livestock and poultry farming tools-such as sensor-based monitoring, automated ventilation, and real-time climate control-emerges as a complementary approach, enabling proactive management of thermal loads. Collectively, the convergence of pharmacological, nutritional, and technological strategies provides a multifaceted framework to mitigate heat stress and improve poultry resilience under climate change. Nevertheless, further longitudinal and field-based studies are required to elucidate mechanistic interactions, validate interventions under commercial conditions, and align practices with sustainability and food safety goals.