Sustainability & efficiency

Genetic parameter estimation for dry matter intake and residual feed intake of springing heifers and first lactation cows

---

Abstract

A commonly used method to define feed efficiency (FE) is residual feed intake (RFI), which is the difference between actual feed intake and the intake required for production and maintenance. Identifying FE cows in their rearing period could potentially accelerate genetic gain by having phenotypic information at an earlier life stage. This study aimed estimate genetic parameters for dry matter intake (DMI) and RFI of heifers from day 1 to 30 before calving (DMI_H and RFI_H) and cows in first lactation (DMI_C and RFI_C). The dataset belongs to an international database that included, among other countries, Denmark, Germany, Canada, and Switzerland, which were used in the analyses. Outliers were removed using the interquartile range method, and records of DMI (kg/day), body weight (kg/day), milk (g/day), fat (g/day), and protein (g/day) yields outside the 1.5*IQR above the 3rd quartile or below the 1st quartile were removed within each country. Traits were standardized to the same average and standard deviation as in Canada. After standardization, outliers were removed again for each trait across all four countries. Heifers with missing records of body weight on day 13 before calving, and cows with missing records of body weight on weeks 14 and 32, had their body weight interpolated for that day or those weeks. RFI_H phenotypes were the residuals of the linear regression of DMI on average daily gain (kg/day) and body weight0.75 (MBW) at day 13 before calving. RFI_C phenotypes were the residuals from the linear regression of DMI on MBW (at weeks 14 and 32 of lactation) and energy-corrected milk (0.25*milk yield + 12.2*fat yield + 7.7*protein yield). The final dataset included 24,011 DMI_H records (977 heifers), 14,958 RFI_H records (600 heifers), 244,532 DMI_C records (4,211 primiparous cows), and 30,428 RFI_C records (2,698 primiparous cows). Univariate and bivariate analyses were performed to estimate genetic parameters using a repeatability animal model in ASREML. The statistical models included different systematic environmental effects for each trait. Heritability estimates were low: 0.07 (±0.02), 0.07 (±0.04), 0.20 (±0.02), and 0.14 (±0.02) for DMI_H, RFI_H, DMI_C and RFI_C, respectively. Repeatability estimates were 0.29 (±0.01), 0.31 (±0.01), 0.43 (±0.02), and 0.43 (±0.01) for DMI_H, RFI_H, DMI_C, and RFI_C, respectively. Estimated genetic correlations were 0.79 (±0.13), 0.44 (±0.21), 0.31 (±0.29), 0.85 (±0.03), and 0.87 (±0.17) between DMI_H and DMI_C, DMI_H and RFI_C, RFI_H and RFI_C, DMI_C and RFI_C, and RFI_H and DMI_C, respectively. One pairwise trait model did not converge (DMI_h and RFI_h). These results suggest that DMI and RFI measured in heifers potentially can serve as complementary traits for selecting for feed efficiency in primiparous cows despite their lower heritabilities. This would enable FE to be measured earlier in life in a shorter measurement period, potentially enhancing selection decisions.

Keywords: 2026

How to Cite:

Abdalla, E., Baes, C., Butty, A., Cunha, S., González-Recio, O., Jahnel, R., Miglior, F., Pryce, J., Schenkel, F. & Stephansen, R., (2026) “Genetic parameter estimation for dry matter intake and residual feed intake of springing heifers and first lactation cows”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286808. doi: https://doi.org/10.31274/wcgalp.24128

Rights: 1