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Longitudinal analysis of residual feed intake in mink using random regression with heterogeneous residual variance
Longitudinal analysis of residual feed intake in mink using random regression with heterogeneous residual variance
Thursday, August 21, 2014: 5:15 PM
Bayshore Grand Ballroom D (The Westin Bayshore)
Abstract Text: Heritability of residual feed intake (RFI) increased from low to high over the growing period in male and female mink. The lowest heritability for RFI (male: 0.04 ± 0.01 standard deviation (SD); female: 0.05 ± 0.01 SD) was in early and the highest heritability (male: 0.33 ± 0.02; female: 0.34 ± 0.02 SD) was achieved at the late growth stages. The genetic correlation between different growth stages for RFI showed a high association (0.91 to 0.98) between early and late growing periods. However, phenotypic correlations were lower from 0.29 to 0.50. The residual variances were substantially higher at the end compared to the early growing period suggesting that heterogeneous residual variance should be considered for analyzing feed efficiency data in mink. This study suggests random regression methods are suitable for analyzing feed efficiency and that genetic selection for RFI in mink is promising.
Keywords:
longitudinal analysis
feed efficiency
heritability
