Exploring the growing phase forest musk deer (Moschus berezovskii) dietary energy requirements based on growth performance and gut microbiota analysis

Abstract

The forest musk deer (FMD) farming industry is currently experiencing rapid growth, yet the dietary energy requirements for FMD remain unclear. Therefore, we explored the optimal dietary digestible energy (DE) for growing phase FMD by providing three diets with different DE levels and analyzing changes in gut microbiota. A total of 20 six-month-old FMD were used in a 62-day trial. Animals were fed either traditional feed (CON, 10.38 MJ/kg DE) or pelleted diets with low (L, 8.87 MJ/kg), medium (M, 10.38 MJ/kg), or high (H, 11.86 MJ/kg) DE levels. The results showed that feeding pelleted diets significantly reduced the incidence of diarrhea (P < 0.05). The average daily gain in the H group was significantly higher than in the M group, and the M group was higher than both the L and CON groups (P < 0.05). Additionally, the H group showed the highest nutrient digestibility and the greatest increase in body measurements (P < 0.05). Analysis of fecal microbiota revealed that α-diversity and the relative abundance of Firmicutes increased with higher dietary energy levels, while the relative abundance of Bacteroidetes decreased. Beneficial bacteria such as Akkermansia and Lachnospira were significantly enriched in the H group. In conclusion, our findings suggest that pelleted diets are suitable for growing phase FMD, with an optimal dietary DE level of 11.86 MJ/kg.

Importance: This study underscores the significance of identifying the optimal dietary digestible energy (DE) for growing forest musk deer (FMD). Pelleted diets with a DE level of 11.86 MJ/kg enhanced growth performance, nutrient digestibility, and gut health, while reducing diarrhea and enriching beneficial gut bacteria, offering valuable insights for improving FMD farming practices.

Keywords: 16S rRNA; Moschus berezovskii; digestible energy; fecal microbiota; growth performance.

Fig 1

Effects of diets with different digestible energy levels on the diarrhea rate in growing phase forest musk deer (FMD). (A–D) Diarrhea rates of FMD during days 1–21, 22–42, 43–62, and the entire trial period. CON, traditional feeding group; L, M, and H represent groups fed pelleted diets with 8.87, 10.38, and 11.86 MJ/kg digestible energy, respectively. *P < 0.05.

Fig 2

(A–E) Effects of diets with different digestible energy levels on feed intake and growth performance in growing phase FMD. ADFI, average daily feed intake; ADG, average daily gain; F/G, feed-to-gain ratio. (F–I) Effects of diets with different digestible energy levels on body measurements in growing phase FMD. △Chest girth, △Withers height, △Body length, △Body oblique length = Final body measurements − Initial body measurements.

Fig 3

Abundance-based coverage estimator, ACE index (A) and venn diagram (B) of fecal microbiota in growing phase FMD fed diets with different digestible energy levels.

Fig 4

Changes in fecal microbiota at the phylum (A) and genus (B) levels in growing phase FMD-fed diets with different digestible energy levels.

Fig 5

Principal coordinates analysis (PCoA) (A) and heatmap of sample distances (B) of fecal microbiota in growing phase FMD-fed diets with different digestible energy levels. Red indicates the closest distances, while blue indicates longer sample-to-sample distances.

Fig 6

Linear discriminant analysis effect size, LEfSe analysis of group differences (A), and microbiota correlation analysis (B) of fecal microbiota in growing phase FMD-fed diets with different digestible energy levels.