First calving age effect on the longevity of cows and milk productivity | Pirmās atnešanās vecuma ietekme uz govju ilgmūžību un piena produktivitāti
2013
Cielava, L., Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Agriculture. Inst. of Agrobiotechnology | Jonkus, D,, Latvia Univ. of Agriculture, Jelgava (Latvia). Faculty of Agriculture. Inst. of Agrobiotechnology
One of the most important traits in dairy farming is cow longevity. Length of productive life in Latvian dairy cow population has significantly decreased in last few years. The aim of this study was to determine how first calving age affects cow life length and lifetime milk productivity. Data of 7504 Latvian brown (LB) breed cows with different bloodiness which were excluded from the herd were analysed in the research. Analysed cows were born in the period of 2002 until 2006. Average life expectancy of cows excluded from the herd was 2286.0 days, productive lifespan was 1467.7 days, but the average number of milking days – 1237.8, and it is 4.06 standard lactations (305 days). Life was significantly longer for cows that calved for the first time after 30 months of age (2404.1 days), but a higher lifetime productivity was noted for cows that have calved at the age 24 to 27 months (20065.6 kg, P is less than 0.05).
显示更多 [+] 显示较少 [-]