Effects of different dietary NFC/NDF on rumen microbiomes of Karakul sheep based on Three Generations of Full-length Amplifiers sequencing

An study was was conducted to investigate the effects of dietary(non fibrous carbohydrate) NFC/(neutral detergent fiber)NDF on ruminal bacteria in Karakul sheep. Twelve Karakul sheep were assigned randomly to four dietary treatments of NFC/NDF (0.78, 1.23, 1.61 and 2.00 respectively) as group 1, 2, 3 to 4. The experiment lasted for four periods, period I (1~18 d), II (19~36 d), III (37~54 d) and IV (55~72 d). Ruminal digesta were collected consecutively for three days to measure pH and bacteria per period. The results indicated that the average ruminal pH and amounts of OTUs were decreased with the increase of dietary NFC/NDF for four periods. At phylum level, Bacteroidetes and Firmicutes were the predominant bacteria of four periods, Bacteroidetes were decreased, while the relative abundance of Firmicutes was increased with dietary NFC/NDF for four periods, but the difference wasn't significant (P>0.05). At genus level, the most relative abundance genus was unidentified-Lachnospiraceae which reached the highest in group 3 for four periods, but the difference wasn't significant (P>0.05). Conclusion: ruminal pH and bacteria were decreased with the increase of dietary NFC/NDF and the most dominant bacteria were not change with dietary NFC/NDF and periods in Karakul sheep.