Effect of Dietary Fat on the Metabolism of Energy and Nitrogen, Serum Parameters, Rumen Fermentation, and Microbiota in twin Hu Male Lambs
BackgroundFat is the main substance that provides energy to animals. However, the use of fat in twin Hu lambs has not been investigated. Thirty pairs of male twin lambs were examined to investigate the effects of dietary fat on the metabolism of energy and nitrogen, ruminal fermentation, and microbial communities. The twins are randomly allotted to two groups (high fat: HF, normal fat: NF). Two diets of equal protein and different fat levels. The metabolism test was made at 50-60 days of age. Nine pairs of twin lambs are slaughtered randomly, and the rumen fluid is collected at 60 days of age.\n\nResultsThe initial body weight (BW) in the HF group did not differ from that of NF group (P > 0.05), but the final BW was tended to higher than that of NF group (0.05 < P < 0.1). The digestive energy (DE), metabolism energy (ME), DE/ME in the HF group tend to be higher than those in the NF group (0.05 < P < 0.1). Ruminal ammonia nitrogen (NH3-N) and the proportion of total volatile fatty acids (TVFA) are higher than that in the NF group (P < 0.05). A high throughput sequencing analysis reveals that there were no differences between the two groups in terms of the richness estimates and diversity indices (P > 0.05). The Proteobacteria and Fibrobacteres phyla were higher than that in NF group (P<0.05).\n\nConclusionsThis study demonstrated that high fat diet before weaning can affect the abundance of several groups of rumen bacteria in rumen, such as significantly increasing phyla Proteobacteria and Fibrobacteres, and genera of Succinivibrio, Alloprevotella, and Saccharofermentans, but significantly decreasing genera of Clostridium IV, Dialister, Roseburia, and Butyrivibrio. And high fat diet improved the performance of lambs at weight gain, energy utilization, and had effect on VFA composition but no effects on serum enzymes and serum hormone.