Alternative poultry production systems consisting of free-range or pasture flock raised poultry continues to increase in popularity. Based on the perceived benefits of poultry products generated from these alternative poultry production systems, they have commercial appeal to consumers. Several factors impact the health and well being of birds raised and maintained in these types of production systems. Exposure to foodborne pathogens and potential for colonization in the gastrointestinal tract has to be considered with these types of production systems. The gastrointestinal tract microbial composition and function of birds grown and maintained in alternative poultry operations may differ depending on diets, breed, and age of bird. Dietary variety and foraging behavior are potential influential factors on bird nutrition. The gastrointestinal tract microbiomes of birds raised under alternative poultry production systems are now being characterized with next-generation sequencing to identify individual microbial members and assess the impact of different factors on the diversity of microbial populations. In this review, the gastrointestinal tract microbiota contributions to free-range or pasture-raised broiler and egg layer production systems, subsequent applications, and potential future directions will be discussed.

中文翻译：

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替代生产系统中肉鸡和蛋鸡的胃肠道微生物组。

由散养或牧场放牧的家禽组成的替代家禽生产系统越来越受欢迎。基于从这些替代的家禽生产系统产生的家禽产品的感知收益，它们对消费者具有商业吸引力。在这些类型的生产系统中，有几个因素会影响饲养和养禽的健康。这些类型的生产系统必须考虑到食源性病原体的暴露以及在胃肠道中定植的可能性。在另类家禽操作中生长和维持的家禽的胃肠道微生物组成和功能可能会因家禽的饮食，品种和年龄而异。饮食种类和觅食行为是影响鸟类营养的潜在因素。现在，采用下一代测序技术对在替代性家禽生产系统下饲养的鸟类的胃肠道微生物群进行鉴定，以鉴定单个微生物成员并评估不同因素对微生物种群多样性的影响。在这篇综述中，将讨论胃肠道微生物群对自由放养或牧场饲养的肉鸡和蛋层生产系统的贡献，后续应用以及潜在的未来方向。