Rabee Alaa Emara
Department of Animal and Poultry Nutrition, Desert Research Center, Cairo, Egypt.
Vet World. 2022 Jan;15(1):35-45. doi: 10.14202/vetworld.2022.35-45. Epub 2022 Jan 17.
Understanding the regulations of rumen microbiota and their fibrolytic capabilities under different forages are essential to improve rumen fermentation and animal feed efficiency. This study aimed to evaluate the changes in the rumen fermentation and the structure and fibrolytic activities of rumen bacteria in camels fed barley straw and Egyptian clover hay.
Three fistulated camels were fed a diet containing barley straw for 30 days; then transitioned to a diet containing Egyptian clover hay for 30 days. In addition, bacterial media enriched with xylan and different cellulose sources, namely, filter paper, wheat straw, and alfalfa hay, were used to evaluate the ability of camel rumen bacteria to produce xylanase and cellulase enzymes.
The camel group fed Egyptian clover hay showed higher crude protein intake, rumen ammonia, total volatile fatty acids, and acetic acid. Moreover, the camel group fed barley straw showed higher neutral detergent fiber intake, rumen pH, and propionic and butyric acids. Principal component analysis showed that bacterial communities were separated based on the forage type. Forage type affected the composition of rumen bacteria and most of the bacterial community was assigned to phylum Bacteroidetes and Firmicutes. Egyptian clover hay diet increased the proportions of genus and ; while fed barley straw diet increased the , , and . The bacterial culture of the Egyptian clover hay fed group produced the greatest xylanase and the bacterial culture of the barley straw fed group produced the maximum cellulase.
Egyptian clover hay is recommended to feed camels in intensive production. Moreover, the bacterial community in the camel rumen is a promising source of lignocellulolytic enzymes.
了解不同草料条件下瘤胃微生物群的调控及其纤维分解能力对于改善瘤胃发酵和动物饲料效率至关重要。本研究旨在评估饲喂大麦秸秆和埃及三叶草干草的骆驼瘤胃发酵、瘤胃细菌结构及纤维分解活性的变化。
三头装有瘤胃瘘管的骆驼先饲喂含大麦秸秆的日粮30天;然后转换为含埃及三叶草干草的日粮30天。此外,使用富含木聚糖和不同纤维素来源(即滤纸、小麦秸秆和苜蓿干草)的细菌培养基来评估骆驼瘤胃细菌产生木聚糖酶和纤维素酶的能力。
饲喂埃及三叶草干草的骆驼组粗蛋白摄入量、瘤胃氨、总挥发性脂肪酸和乙酸含量较高。此外,饲喂大麦秸秆的骆驼组中性洗涤纤维摄入量、瘤胃pH值以及丙酸和丁酸含量较高。主成分分析表明,细菌群落根据草料类型而分离。草料类型影响瘤胃细菌的组成,且大多数细菌群落归属于拟杆菌门和厚壁菌门。埃及三叶草干草日粮增加了属和属的比例;而饲喂大麦秸秆日粮增加了属、属和属的比例。饲喂埃及三叶草干草组的细菌培养物产生的木聚糖酶最多,饲喂大麦秸秆组的细菌培养物产生的纤维素酶最多。
建议在集约化生产中用埃及三叶草干草饲喂骆驼。此外,骆驼瘤胃中的细菌群落是木质纤维素酶的一个有前景的来源。