Residual Feed Intake and Rumen Metabolism in Growing Pelibuey Sheep

Abstract

This study was carried out to evaluate the residual feed intake (RFI), volatile fatty acid (VFA) production and enteric methane (CH4) from growing Pelibuey sheep. In this case, 12 non-castrated Pelibuey with an initial average live weight (LW) of 21.17 ± 3.87 kg and an age of 3 months, were housed in individual pens and fed a basal diet with 16% of crude protein and 11 MJ ME for 45 days. Dry matter intake (DMI) was measured and the daily weight gain (DWG) was calculated using a linear regression between the LW and experimental period. Mean metabolic live weight (LW0.75) was calculated. RFI was determined by linear regression with DWG and LW0.75 as independent variables. Lambs were classified as low, medium, and high RFI. Feed efficiency was determined as DWG/DMI. For determining rumen pH, ammonia nitrogen concentration NH3-N), and VFA, ruminal fluid was obtained using an esophageal probe on day 40. Feed intake of low RFI lambs was approximately 16% lower (p < 0.05) while growth rate was not significantly different. Their average energy loss, expressed as CH4 production per kilogram of metabolic weight, was 17% lower (p < 0.05).

Alterations in nutrient digestion and utilization associated with different residual feed intake in Hu sheep

“…Recent studies have revealed microbial differences in the rumen between high and low RFI sheep ( Perea et al., 2017 ; Zhang et al., 2021 ; Arce-Recinos et al., 2022 ). More importantly, a microbial profile of 6 rumen microbial species could be used to rank the FE of sheep ( Ellison et al., 2019 ), but microbiota in both the rumen and intestinal tract should be considered, as the gastrointestinal tract microbiota are indispensable to the nutritive function of animals ( Perea et al., 2017 ).…”