Bone metabolism and inflammation in slow- and fast-growing domestic fowl

现代家禽(肉鸡和蛋鸡)经过了60多年的密集遗传选择。肉用型(锅炉型)鸡生长速度快，胸肌沉积，饲料到肌肉的有效转化。蛋型鸡(蛋鸡)由于产蛋量高，饲料到蛋块的转换效率高而被挑选出来。在这两种情况下，商业选择可能导致了无意中的选择，而这些因素抵消了快速增长或高水平的鸡蛋生产。炎症反应是先天免疫系统的一部分，可引起全身性影响，如采食量减少、生长速度减慢和产蛋量减少。即使是轻微的炎症也可能微妙地降低商品鸡的生产性能。肉鸡的快速生长速度降低了它们正常形成骨骼的能力，蛋鸡的高产量会导致骨钙流失，从而导致骨质疏松症。炎症免疫系统的细胞与骨代谢相关的细胞是相关的，先前的研究表明，实验诱导的炎症对鸡的骨代谢有负面影响。

Modern poultry (meat-type and egg laying chickens) have been intensively genetically selected for over 60 years. Meat-type (boiler) chickens have been selected for rapid growth rate, breast muscle deposition, and efficient conversion of feed to muscle. Egg-type chickens (laying hens) have been selected for high levels of egg production and efficient conversion of feed to egg mass. In both cases, commercial selection has likely resulted in inadvertent selection against factors that counteract rapid growth or high levels of egg production. The inflammatory response is part of the innate immune system, and can cause systemic effects such as decreased feed intake, slower growth rate, and decreased egg production. Even mild inflammation may subtly reduce performance of commercial chickens. The rapid growth rate of broilers reduces the ability of the birds to properly form bones, and the high output of eggs in layers creates a drain on bone calcium that can lead to osteoporosis. Cells of the inflammatory immune system and cells related to bone metabolism are related, and previous research has shown that experimentally-induced inflammation has a negative effect on bone metabolism in chickens.