Table 1
Descriptive statistics of studied body conformation traits and milking parameters
| Trait | Mean value | SD | CV (%) |
|---|---|---|---|
| Body conformation traits | |||
| UD | 6.0 | 1.2 | 20.00 |
| TL | 4.7 | 1.1 | 23.65 |
| RUW | 5.3 | 1.0 | 18.24 |
| RUH | 5.9 | 0.9 | 14.73 |
| RTP | 6.6 | 1.1 | 17.26 |
| FTP | 5.2 | 1.0 | 18.72 |
| FA | 5.5 | 1.0 | 18.44 |
| CL | 5.9 | 1.3 | 22.42 |
| AY | 6.2 | 1.0 | 16.18 |
| FTA | 5.1 | 1.3 | 25.59 |
| RLRV | 5.6 | 1.3 | 23.28 |
| HS | 145.3 | 4.1 | 2.81 |
| BD | 6.2 | 1.2 | 18.39 |
| CW | 5.2 | 1.3 | 25.26 |
| RA | 5.3 | 1.1 | 21.12 |
| RW | 5.4 | 1.0 | 19.46 |
| RLS | 5.6 | 1.0 | 18.04 |
| Milking parameters | |||
| MY | 31.03 | 7.17 | 23.09 |
| ME | 1.56 | 0.39 | 24.87 |
| AN | 1.40 | 0.31 | 22.14 |
| AT | 11.52 | 6.15 | 53.38 |
Abbreviations: UD: udder depth [pts]; TL: teat length [pts]; RUW: rear udder width [pts]; RUH: rear udder height [pts]; RTP: rear teat placement [pts]; FTP: front teat placement [pts]; FA: fore udder attachment [pts]; CL: central ligament [pts]; AY: angularity [pts]; FTA: foot angle [pts]; RLRV: rear legs rear view [pts]; HS: height at sacrum [cm]; BD: body depth [pts]; CW: chest width [pts]; RA: rump angle [pts]; RW: rump width [pts]; RLS: rear legs set [pts]; MY: milk yield [kg/day]; ME: milking efficiency [kg/min]; AN: attachment number [n/milking]; AT: attachment time [s/milking].
Table 2
Heritabilities of studied body conformation traits and milking parameters
| Trait | σ 2 a | SE (σ 2 a ) | σ 2 e | SE (σ 2 e ) | h 2 | SE (h2) |
|---|---|---|---|---|---|---|
| Body conformation traits | ||||||
| UD | 0.5142 | 0.1542 | 0.6505 | 0.1370 | 0.442 | 0.122 |
| TL | 0.4584 | 0.1207 | 0.7077 | 0.1007 | 0.393 | 0.096 |
| RUW | 0.2627 | 0.0892 | 0.5419 | 0.0831 | 0.327 | 0.105 |
| RUH | 0.1362 | 0.0636 | 0.5345 | 0.0639 | 0.203 | 0.092 |
| RTP | 0.1521 | 0.0842 | 0.9379 | 0.0913 | 0.140 | 0.075 |
| FTP | 0.1801 | 0.0978 | 0.7180 | 0.0962 | 0.201 | 0.106 |
| FA | 0.4089 | 0.1530 | 0.6148 | 0.1368 | 0.399 | 0.140 |
| CL | 0.4194 | 0.1880 | 1.1767 | 0.1788 | 0.263 | 0.113 |
| AY | 0.3188 | 0.1034 | 0.5064 | 0.0921 | 0.386 | 0.116 |
| FTA | 0.6578 | 0.2250 | 0.8459 | 0.1977 | 0.438 | 0.138 |
| RLRV | 0.1747 | 0.0813 | 1.0686 | 0.0937 | 0.141 | 0.064 |
| HS | 5.5741 | 1.1989 | 3.7518 | 0.9898 | 0.598 | 0.112 |
| BD | 0.2586 | 0.1113 | 0.7926 | 0.1076 | 0.246 | 0.102 |
| CW | 0.2753 | 0.1239 | 0.9090 | 0.1207 | 0.233 | 0.101 |
| RA | 0.2556 | 0.1159 | 0.8704 | 0.1143 | 0.227 | 0.099 |
| RW | 0.2527 | 0.1092 | 0.7832 | 0.1063 | 0.244 | 0.101 |
| RLS | 0.1689 | 0.0922 | 0.7942 | 0.0937 | 0.175 | 0.093 |
| Milking parameters | ||||||
| MY | 10.1183 | 3.8609 | 24.9099 | 3.6026 | 0.289 | 0.104 |
| ME | 0.0557 | 0.0177 | 0.0871 | 0.0254 | 0.390 | 0.115 |
| AN | 0.0191 | 0.0099 | 0.0737 | 0.0095 | 0.205 | 0.104 |
| AT | 4.9859 | 2.8380 | 29.3218 | 2.9548 | 0.145 | 0.080 |
σ 2 a = additive genetic variance, σ 2 e = residual variance.
Abbreviations: UD: udder depth [pts]; TL: teat length [pts]; RUW: rear udder width [pts]; RUH: rear udder height [pts]; RTP: rear teat placement [pts]; FTP: front teat placement [pts]; FA: fore udder attachment [pts]; CL: central ligament [pts]; AY: angularity [pts]; FTA: foot angle [pts]; RLRV: rear legs rear view [pts]; HS: height at sacrum [cm]; BD: body depth [pts]; CW: chest width [pts]; RA: rump angle [pts]; RW: rump width [pts]; RLS: rear legs set [pts]; MY: milk yield [kg/day]; ME: milking efficiency [kg/min]; AN: attachment number [n/milking]; AT: attachment time [s/milking].
Table 3
Genetic (r G) and phenotypic correlations (r P) between the body conformation traits and milk yield, ME, AN, and AT
| Traits | r G | r P | r G | r P | r G | r P | r G | r P |
|---|---|---|---|---|---|---|---|---|
| MY | ME | AN | AT | |||||
| UD | –0.281 | –0.096 | 0.174 | –0.001 | –0.185 | –0.043 | –0.456 | –0.060 |
| TL | 0.099 | 0.102 | –0.251 | –0.139 | 0.254 | –0.045 | 0.798 | –0.070 |
| RUW | 0.162 | 0.291 | –0.105 | 0.087 | 0.844 | –0.003 | 0.977 | –0.012 |
| RUH | 0.162 | 0.199 | –0.121 | 0.100 | 0.494 | –0.035 | 0.939 | –0.025 |
| RTP | –0.053 | 0.006 | –0.159 | –0.024 | 0.593 | 0.035 | 0.884 | 0.070 |
| FTP | 0.144 | 0.024 | 0.142 | –0.020 | –0.038 | –0.005 | –0.381 | 0.026 |
| FA | 0.102 | 0.191 | 0.198 | –0.017 | –0.607 | –0.099 | –0.567 | –0.128 |
| CL | –0.356 | 0.091 | –0.146 | 0.019 | 0.293 | –0.007 | 0.397 | 0.023 |
| AY | 0.568 | 0.287 | 0.354 | 0.108 | 0.198 | –0.020 | 0.782 | –0.021 |
| FTA | 0.338 | 0.138 | 0.051 | –0.035 | 0.466 | 0.022 | 0.799 | –0.014 |
| RLRV | –0.523 | 0.103 | –0.339 | –0.010 | 0.962 | 0.077 | 0.970 | 0.072 |
| HS | –0.020 | 0.127 | 0.058 | 0.032 | 0.062 | –0.072 | –0.215 | –0.100 |
| BD | 0.973 | 0.308 | 0.646 | 0.048 | –0.150 | –0.034 | 0.231 | –0.046 |
| CW | –0.041 | 0.122 | 0.389 | 0.009 | –0.379 | –0.100 | –0.575 | –0.129 |
| RA | 0.483 | 0.026 | –0.139 | –0.024 | –0.196 | 0.061 | –0.468 | 0.046 |
| RW | –0.025 | 0.125 | 0.662 | –0.024 | –0.223 | –0.075 | –0.227 | –0.080 |
| RLS | –0.124 | –0.116 | –0.382 | 0.085 | 0.074 | –0.015 | 0.024 | –0.021 |
Abbreviations: UD: udder depth [pts]; TL: teat length [pts]; RUW: rear udder width [pts]; RUH: rear udder height [pts]; RTP: rear teat placement [pts]; FTP: front teat placement [pts]; FA: fore udder attachment [pts]; CL: central ligament [pts]; AY: angularity [pts]; FTA: foot angle [pts]; RLRV: rear legs rear view [pts]; HS: height at sacrum [cm]; BD: body depth [pts]; CW: chest width [pts]; RA: rump angle [pts]; RW: rump width [pts]; RLS: rear legs set [pts]; MY: milk yield [kg/day]; ME: milking efficiency [kg/min]; AN: attachment number [n/milking]; AT: attachment time [s/milking].