Abstract:
In modern animal husbandry, stress can be viewed as an automatic response triggered by exposure to adverse environmental conditions. This response can range from mild discomfort to severe consequences, including mortality. The poultry industry, which significantly contributes to human nutrition, is not exempt from this issue. Although genetic selection has been employed for several decades to enhance production output, it has also resulted in poor stress resilience. Stress is manifested through a series of physiological reactions, such as the identification of the stressful stimulus, activation of the sympathetic nervous system and the adrenal medulla, and subsequent hormonal cascades. While brief periods of stress can be tolerated, prolonged exposure can have more severe consequences. For instance, extreme fluctuations in environmental temperature can lead to the accumulation of reactive oxygen species, impairment of reproductive performance, and reduced immunity. In addition, excessive noise in poultry slaughterhouses has been linked to altered bird behaviour and decreased production efficiency. Mechanical vibrations have also been shown to negatively impact the meat quality of broilers during transport as well as the egg quality and hatchability in hatcheries. Lastly, egg production is heavily influenced by light intensity and regimens, and inadequate light management can result in deficiencies, including visual anomalies, skeletal deformities, and circulatory problems. Although there is a growing body of evidence demonstrating the impact of environmental stressors on poultry physiology, there is a disproportionate representation of stressors in research. Recent studies have been focused on chronic heat stress, reflecting the current interest of the scientific community in climate change. Therefore, this review aims to highlight the major abiotic stressors in poultry production and elucidate their underlying mechanisms, addressing the need for a more comprehensive understanding of stress in diverse environmental contexts.
摘要:
在现代畜牧业中,压力可以被视为由暴露于不利环境条件触发的自动响应。这种反应可以从轻度不适到严重后果,包括死亡率。家禽业,这对人类营养有很大的贡献,不能免除这个问题。尽管基因选择已经使用了几十年来提高产量,这也导致了不良的压力弹性。压力是通过一系列的生理反应表现出来的,比如压力刺激的识别,激活交感神经系统和肾上腺髓质,和随后的荷尔蒙级联。虽然可以忍受短暂的压力,长时间接触会产生更严重的后果。例如,环境温度的极端波动会导致活性氧的积累,生殖性能受损,免疫力降低。此外,家禽屠宰场噪音过多与鸟类行为改变和生产效率下降有关。机械振动也已被证明对运输过程中肉鸡的肉质量以及孵化场中的蛋质量和孵化率产生负面影响。最后,产蛋受到光照强度和方案的严重影响,光管理不足会导致缺陷,包括视觉异常,骨骼畸形,和循环问题。尽管越来越多的证据表明环境压力因素对家禽生理的影响,研究中压力源的表现不成比例。最近的研究集中在慢性热应激,反映了科学界目前对气候变化的兴趣。因此,这篇综述旨在强调家禽生产中的主要非生物应激源,并阐明其潜在机制,解决需要更全面地了解不同环境背景下的压力。