Effect of feed efficiency on growth performance, body composition, and fat deposition in growing Hu lambs

Abstract

The present study aimed to investigate the relationship between growth performance, body composition, and fat deposition factors, and feed efficiency in growing lambs. We measured average daily feed intake (ADFI) and body weight (BW) from 653 Hu sheep that were fed a pellet diet. The residual feed intake (RFI) not significantly genetic and phenotypic correlated with the metabolic body weight (MBW) and average daily gain (ADG), but it was significantly genetic and phenotypic correlated with ADFI and the feed conversion ratio (FCR) (p < 0.01). However, the FCR was significantly associated with growth traits (p < 0.01). With the same ADG, body fat deposition was greater in animals with low feed efficiency compared with high feed efficiency. Therefore, excessive fat deposition can affect the feed efficiency of the body, and organ weight and gut-weight have a greater impact on the feed efficiency of lambs. The reticulum stomach and jejunum of lambs with a low RFI were smaller compared with that in the high RFI, indicating that lambs with a low RFI have less intake and a higher absorption rate. Small organs, such as the liver, of lambs with high FE might be associated with low energy expenditure and slow metabolism. This study provides a new perspective to study the biological processes responsible for feed efficiency variation in lambs.

Keywords:

• Carcass traits
• fat deposition
• feed conversion ratio
• growth performance
• residual feed intake
• visceral organs

Disclosure statement

The authors declare no conflict of interest.

Author contributions

X. X. Zhang, W. M. Wang, G. Z. Li: data curation, investigation, and writing-original draft preparation. X. X. Zhang, D. Y. Zhang: investigation and visualization. F. D. Li, L. F. Yuan, X. L. Li, Y. K. Zhang, Y. Zhao, and Q. Z. Song: investigation and validation. W. M. Wang: conceptualization, formal analysis, and writing – review and editing. All authors have read and approved the final manuscript.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (grant nos. 31760651 and 31960653) and the Fuxi Young Talents Fund of Gansu Agricultural University (Gaufx-03Y11).