Nutritional Value and Health Implications of Meat from Monogastric Animals Exposed to Heat Stress.

Abstract

Heat stress (HS), driven by rising global temperatures, significantly impairs the nutritional composition and sensory quality of meat from monogastric animals, particularly swine and poultry. HS induces physiological disturbances, including reduced feed intake, oxidative stress, and endocrine disruption, which together reduce muscle protein content by 10-15% and essential amino acid levels (e.g., lysine, methionine, threonine) by 15-25%. Lipid profiles are also altered, with up to 30% reductions in polyunsaturated fatty acids (PUFAs), especially omega-3s, and an increased saturated fat content. Additionally, HS reduces the retention of vitamins E, A, D, and C by 20-50% and critical minerals such as selenium, zinc, and iron, compromising antioxidant capacity, immune function, and oxygen transport. These changes diminish meat tenderness, juiciness, flavour, and colour stability, leading to reduced consumer appeal and dietary quality. The consumption of heat-stressed meat may elevate risks for cardiovascular disease, oxidative stress, and micronutrient deficiencies. Mitigation strategies, including dietary antioxidant and osmolyte supplementation, genetic selection for thermotolerance, and optimised feeding practices, can reduce oxidative damage by up to 40% and improve nutrient retention. This review synthesises the current evidence on HS-induced meat quality deterioration and explores nutritional and management strategies to protect animal productivity and human health.