Effect of conformation traits on longevity of dairy cows in Latvia
2016
Cielava, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Paura, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Cow lifespan is one of most important economical traits in every dairy farm and is affected by different environmental factors. One of genetic factors that affect longevity is cow conformation traits, which varies within different breeds, farms and animals. The aim in this study was to determine how stature and linear conformation traits affect cow lifespan and lifetime milk productivity. In the study, data about 34806 crossbred Holstein Black and White and 38201 Red cow group breed cows, which ended at least one full lactation, and were culled from 2002 – 2012 year were analysed. Data about cow productivity and culling was obtained from Latvian Agricultural Data centre. In the study, data about cow stature, udder depth, central ligament, teat length, and rear and front teat placement were analysed. Conformation traits were distributed in 3 groups. The average lifespan of analysed cows was 1869.9 days in which average 18550.8 kg energy corrected milk (ECM) was obtained. Holstein Black and White cows characterize with shorter lifespan (1833.7 days) than red breed group cows, but lifetime productivity is for 2339.1 kg ECM higher than for average red breed cow. Significantly longer (p is less than 0.05) lifespan – 2031.6 days was in cow group with stature 100 – 135 cm, but in cow group with stature more than 146 cm there is significantly higher lifetime and life day productivity. There is a significant difference between lifetime milk productivity and rear and front teat placement. Significantly higher productivity was given by cows with teat placement inside of quarter (linear evaluation 6- 9 points).
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