Grant Ar'Quette, Gay Cyril G, Lillehoj Hyun S
a Animal Biosciences and Biotechnology Laboratory, Agricultural Research Service , US Department of Agriculture , Beltsville , MD , USA.
b National Program Staff - Animal Health, Agricultural Research Service , US Department of Agriculture , Beltsville , MD , USA.
Avian Pathol. 2018 Aug;47(4):339-351. doi: 10.1080/03079457.2018.1464117. Epub 2018 May 2.
The increasing occurrence of antibiotic-resistant bacteria combined with regulatory pressure and consumer demands for foods produced without antibiotics has caused the agricultural industry to restrict its practice of using antibiotic growth promoters (AGP) in food animals. The poultry industry is not immune to this trend, and has been actively seeking natural alternatives to AGP that will improve the health and growth performance of commercial poultry flocks. Bacillus probiotics have been gaining in popularity in recent years as an AGP alternative because of their health-promoting benefits and ability to survive the harsh manufacturing conditions of chicken feed production. This review provides an overview of several modes of action of some Bacillus direct-fed microbials as probiotics. Among the benefits of these direct-fed microbials are their production of naturally synthesized antimicrobial peptides, gut flora modulation to promote beneficial microbiota along the gastrointestinal tract, and various immunological and gut morphological alterations. The modes of action for increased performance are not well defined, and growth promotion is not equal across all Bacillus species or within strains. Appropriate screening and characterization of Bacillus isolates prior to commercialization are necessary to maximize poultry growth to meet the ultimate goal of eliminating AGP usage in animal husbandry.
抗生素耐药菌的日益增多，加上监管压力以及消费者对无抗生素生产食品的需求，促使农业行业限制在食用动物中使用抗生素生长促进剂（AGP）的做法。家禽业也未能幸免于此趋势，一直在积极寻找AGP的天然替代品，以改善商业家禽群的健康状况和生长性能。近年来，芽孢杆菌益生菌作为AGP的替代品越来越受欢迎，因为它们具有促进健康的益处，并且能够在鸡饲料生产的恶劣制造条件下存活。本综述概述了一些芽孢杆菌直接投喂微生物作为益生菌的几种作用模式。这些直接投喂微生物的益处包括它们产生天然合成的抗菌肽、调节肠道菌群以促进胃肠道有益微生物群的生长，以及各种免疫和肠道形态学改变。性能提升的作用模式尚未明确界定，并非所有芽孢杆菌种类或菌株内的生长促进效果都相同。在商业化之前，对芽孢杆菌分离株进行适当的筛选和鉴定，对于最大限度地促进家禽生长以实现畜牧业中消除AGP使用这一最终目标是必要的。
