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Table 2 Variance components, proportion of variances over total phenotypic variance and heritabilities for calving interval (CI), milk, fat and protein yields in Holstein and Jersey cows

From: Accounting for dominance to improve genomic evaluations of dairy cows for fertility and milk production traits

Breed Model Parameter Trait
CI Milk yield Fat yield Protein yield
Holstein A σ 2 a 58 (12) 239,580 (15,500) 257 (20) 145 (12)
σ 2 perm 43 (18) 150,320 (10,569) 255 (16) 171 (10)
σ 2 e 2681 (28) 546,590 (6487) 889 (11) 522 (6)
h 2 a 0.021 (0.004) 0.256 (0.014) 0.184 (0.013) 0.174 (0.013)
(σ 2 a  + σ 2 perm )/σ 2 p 0.036 (0.006) 0.416 (0.009) 0.366 (0.009) 0.378 (0.009)
A + D σ 2 a 58 (12) 239,810 (15,486) 257 (20) 145 (12)
σ 2 d 34 (22) 30,492 (12,464) 54 (20) 27 (12)
σ 2 perm 8 (29) 118,360 (16,161) 200 (25) 143 (15)
σ 2 e 2680 (28) 546,520 (6486) 889 (11) 522 (6)
h 2 a 0.021 (0.004) 0.256 (0.014) 0.184 (0.013) 0.174 (0.013)
h 2 d 0.012 (0.008) 0.033 (0.013) 0.038 (0.014) 0.032 (0.014)
σ 2 d /(σ 2 a  + σ 2 d ) 0.366 0.113 0.173 0.155
(σ 2 a  + σ 2 d  + σ 2 perm )/σ 2 p 0.036 (0.006) 0.416 (0.009) 0.365 (0.009) 0.377 (0.009)
Jersey A σ 2 a 63 (20) 137,410 (11,868) 189 (21) 106 (11)
σ 2 perm 114 (31) 98,832 (7852) 223 (17) 131 (9)
σ 2 e 2749 (43) 214,400 (3720) 606 (10) 281 (5)
h 2 a 0.022 (0.007) 0.305 (0.022) 0.186 (0.019) 0.204 (0.020)
(σ 2 a  + σ 2 perm )/σ 2 p 0.061 (0.009) 0.524 (0.011) 0.405 (0.012) 0.457 (0.012)
A + D σ 2 a 63 (20) 137,800 (11,858) 189 (21) 105 (11)
σ 2 d 0 23,089 (8892) 67 (21) 37 (11)
σ 2 perm 114 (31) 74,510 (11,473) 153 (26) 93 (14)
σ 2 e 2749 (43) 214,450 (3721) 606 (10) 281 (5)
h 2 a 0.022 (0.007) 0.306 (0.022) 0.186 (0.019) 0.204 (0.020)
h 2 d 0 0.051 (0.020) 0.066 (0.020) 0.071 (0.021)
σ 2 d /(σ 2 a  + σ 2 d ) 0 0.144 0.263 0.258
(σ 2 a  + σ 2 d  + σ 2 perm )/σ 2 p 0.061 (0.009) 0.523 (0.011) 0.403 (0.012) 0.455 (0.012)
  1. Model A = taking only additive effects into account
  2. Model A + D = taking both additive and dominance effects into account
  3. σ 2 a  = additive variance
  4. σ 2 perm  = permanent environmental variance
  5. σ 2 e  = residual variance
  6. h 2 a  = additive heritability
  7. σ 2 p  = total phenotypic variance
  8. σ 2 d  = dominance variance
  9. h 2 d  = dominance heritability
  10. Standard errors (SE) in parentheses