Katiyar Rahul, Gonmei Chamniugongliu, Deori Sourabh, Singh Mahak, Abedin Sayed Nabil, Rautela Rupali, Singh Ningthoujam Suraj, Chakravarty Himsikha, Das Meena, Choudhury B U, Mishra Vinay Kumar
ICAR Research Complex for NEH Region, Umiam, Meghalaya, India.
ICAR Research Complex for NEH Region, Nagaland Centre, Medziphema, Nagaland, India.
Trop Anim Health Prod. 2025 Mar 21;57(3):139. doi: 10.1007/s11250-025-04387-7.
Heat stress (HS) poses a significant challenge to pig production worldwide, with far-reaching consequences for productivity, reproduction, and overall animal welfare. Stress, broadly defined as the nonspecific physiological response to environmental demands, disrupts homeostasis, leading to health imbalances, behavioral changes, and reduced productive efficiency. Pigs are particularly susceptible to HS due to their limited thermoregulatory capacity, influenced by a low density of functional sweat glands and a thick subcutaneous fat layer. Rising global temperatures have exacerbated HS-induced economic losses in the swine industry, manifesting as decreased growth rates, poor reproductive performance, reduced feed efficiency, increased morbidity, and mortality. HS impairs pig production by diminishing feed intake and nutrient availability, which leads to reduced growth, suboptimal carcass quality, and compromised reproduction. Sows experience increased anestrus, extended weaning-to-estrus intervals, and smaller litter sizes, while boars exhibit reduced semen quality and fertility. The genetic selection for higher productivity has inadvertently lowered heat tolerance, as metabolic heat production increases with improved production traits. Furthermore, inadequate environmental management in pig housing exacerbates the impact of HS. Variations in heat tolerance among pigs underscore the importance of understanding genetic, physiological, and environmental factors influencing their response to HS. Research reveals genetic differences in thermotolerance, offering potential avenues for selective breeding to improve resilience. Effective management strategies, including nutritional adjustments, environmental modifications, and genetic selection, are crucial for mitigating the negative effects of HS and enhancing pig productivity. This review highlights the multifaceted impacts of HS on swine production, explores the physiological and reproductive consequences, and discusses adaptive and ameliorative measures to address these challenges, with a focus on maintaining sustainable pig production in the face of climatic changes.
热应激（HS）对全球养猪业构成了重大挑战，对生产力、繁殖力和动物整体福利产生了深远影响。应激被广泛定义为对环境需求的非特异性生理反应，它会破坏体内平衡，导致健康失衡、行为改变和生产效率降低。猪由于其有限的体温调节能力而特别容易受到热应激的影响，这受到功能性汗腺密度低和皮下脂肪层厚的影响。全球气温上升加剧了养猪业因热应激导致的经济损失，表现为生长速度下降、繁殖性能差、饲料效率降低、发病率和死亡率增加。热应激通过减少采食量和营养物质供应来损害养猪生产，进而导致生长减缓、胴体品质欠佳和繁殖能力受损。母猪出现发情期延长、断奶至发情间隔延长以及产仔数减少的情况，而公猪则表现出精液质量和生育能力下降。对更高生产力的基因选择无意中降低了耐热性，因为随着生产性状的改善，代谢产热会增加。此外，猪舍环境管理不善加剧了热应激的影响。猪之间耐热性的差异凸显了了解影响它们对热应激反应的遗传、生理和环境因素的重要性。研究揭示了耐热性的遗传差异，为通过选择性育种提高恢复力提供了潜在途径。有效的管理策略，包括营养调整、环境改造和基因选择，对于减轻热应激的负面影响和提高猪的生产力至关重要。本综述强调了热应激对养猪生产的多方面影响，并探讨了其生理和繁殖后果，还讨论了应对这些挑战的适应性和改善措施，重点是在气候变化的情况下维持可持续的养猪生产。
