Characteristics and Functions of Rumen Fermentation Parameters and Rumen Microflora in Preweaning Lambs

ABSTRACT By gaining insight into the rumen microbiota of young lambs, feeding and management strategies of lambs can be optimized to enhance sheep performance. This study examined rumen development, rumen fermentation parameters, and microbial community composition at different stages of lamb growth, specifically on Days 7, 28, and 56. Rumen fermentation parameters, rumen development and rumen microflora of lambs at different days of age were comparatively analyzed. There were significant differences in rumen papilla length between D7, D28 and D56 ( p < 0.001), and significant differences in rumen papilla width at D7 compared with D28 and D56 ( p < 0.001); There were significant differences in rumen papilla length between D7, D28 and D56 ( p < 0.001) and A/P (Acetic acid/Propionic acid) was significantly higher at D7 than D28 and 56 d ( p < 0.001); 16S rRNA sequencing revealed distinct shifts in bacterial abundance: the abundance of Fusobacteria at D7 was significantly higher than that at D28 and D56 ( p = 0.043); The abundance of Euryarchaeota was significantly higher at D28 than that at D7 ( p = 0.023); The abundance of Cyanobacteria and Tenericutes was significantly higher at D56 than that at D7 ( p = 0.011; p = 0.038), and the abundance of Melainabacteria was significantly higher at D56 than that at D7 and D28 ( p = 0.034); At the genus level, the abundance of unidentified_Prevotellaceae was significantly higher at D28 and D56 than that at D7 ( p = 0.036). Additionally, the abundance of Lactobacillus was significantly lower at D28 than that at D7 ( p = 0.018); The abundance of Bacteroides was significantly lower at D56 than that in D7 ( p = 0.033). In conclusion, with advancing age of lames, their rumen continued to develop, while the rumen microbiota began to stabilize.