TABLE 5

Effect of the GHR F279Y mutation on milk yield and composition

TraitFY - FF (±SE)YY - FF (±SE)Embedded Image PQTL
A. Data sets I + II (Dutch Holstein-Friesian sires—DYDs)
Genotype frequencies: FF, 0.67; FY, 0.31; YY, 0.02; n = 1263
Milk yield (kg)67 ± 16128 ± 490.0176.8E-05
Fat yield (kg)-1.4 ± 0.6-4.1 ± 1.80.0070.015
Protein yield (kg)-0.1 ± 0.40.2 ± 1.30.0000.961
Fat %-0.06 ± 0.01-0.14 ± 0.030.0352.2E-09
Protein %-0.033 ± 0.01-0.06 ± 0.010.0577.3E-15
B. Data set III (New Zealand Holstein-Friesian sires—DYDs)
Genotype frequencies: FF, 0.68; FY, 0.29; YY, 0.03; n = 1550
Milk yield (kg)89 ± 1768 ± 450.0108.4E-06
Fat yield (kg)-1.5 ± 0.7-5.2 ± 1.70.0060.01
Protein yield (kg)-1.0 ± 0.5-4.4 ± 1.30.0040.007
Fat %-0.13 ± 0.02-0.20 ± 0.020.0321.2E-12
Protein %-0.10 ± 0.01-0.17 ± 0.040.0948.0E-32
C. Data set IV (New Zealand Jersey sires—DYDs)
Genotype frequencies: FF, 0.89; FY, 0.10; YY, 0.01; n = 959
Milk yield (kg)112 ± 33441 ± 1020.0293.35E-05
Fat yield (kg)0.1 ± 1.5-2.3 ± 4.70.0000.97
Protein yield (kg)0.3 ± 1.16.3 ± 3.30.0030.31
Fat %-0.19 ± 0.05-0.68 ± 0.020.0305.62E-05
Protein %-0.13 ± 0.02-0.30 ± 0.080.0591.1E-07
D. Data set V (New Zealand Holstein-Friesian cows—LVs)
Genotype frequencies: FF, 0.73; FY, 0.24; YY, 0.03; n = 485
Milk yield (kg)87 ± 4899 ± 1290.0070.17
Fat yield (kg)-1.3 ± 2.2-8.3 ± 5.90.0040.34
Protein yield (kg)-0.6 ± 1.5-3.1 ± 4.10.0010.73
Fat %-0.14 ± 0.05-0.31 ± 0.130.0230.004
Protein %-0.10 ± 0.02-0.19 ± 0.060.0532.3E-06
E. Data set VI (New Zealand Jersey cows—LVs)
Genotype frequencies: FF, 0.81; FY, 0.17; YY, 0.02; n = 387
Milk yield (kg)162 ± 5259 ± 1350.0250.009
Fat yield (kg)-2.1 ± 2.7-8.3 ± 6.90.0050.40
Protein yield (kg)1.2 ± 1.7-1.4 ± 4.50.0010.73
Fat %-0.28 ± 0.06-0.33 ± 0.170.0556.7E-05
Protein %-0.13 ± 0.03-0.10 ± 0.070.0581.6E-05
  • FY - FF, difference between the mean trait values of the FY and FF genotypes = effect of one Y dose; YY - FF, difference between the mean trait values of the YY and FF genotypes = effect of two Y doses; Embedded Image , proportion of the trait variability explained by the GHR F279Y genotype, computed as described in materials and methods; PQTL, statistical significance of the GHR F279Y genotype effect.