<abstract xmlns="http://www.w3.org/1999/xhtml"><p>A total of 2,484 lactations in 760 Polish Holstein-Friesian cows were analysed. Calculations were made of length of life, length of productive life, total number of days in milk, number of calvings, ratio of days in milk to length of productive life, lifetime milk yield (kg), daily yield at the peak of lactation (kg) and lactation persistency as the percentage difference between daily milk production in the 2nd and 10th month in milk. The cows were divided into three groups according to lactation persistency (decrease in production): group I – up to 30%, group II – 30.1–50% and group III – over 50%. Lactation persistency significantly influenced (P≤0.01) length of life and efficiency of milk production in the analysed cow population. Cows with yield over 30 kg at the peak of lactation followed by a moderate decrease (40%) lived longest (over 6 years) and produced the most milk (nearly 28,000 kg). Yield of primiparous cows at the peak of lactation and its course were found to have a significant effect on length of life and lifetime milk production. The long period of high peak yield (over 30 kg of milk) in the primiparous cows in group I (with the best lactation persistency) in the long term proved to be detrimental, as these cows had the shortest productive life (2.3 lactations on average) and lifetime milk yield about 4,000 kg lower than in the cows in groups II and II (with the poorer lactation persistency).</p></abstract>

A total of 2,484 lactations in 760 Polish Holstein-Friesian cows were analysed. Calculations were made of length of life, length of productive life, total number of days in milk, number of calvings, ratio of days in milk to length of productive life, lifetime milk yield (kg), daily yield at the peak of lactation (kg) and lactation persistency as the percentage difference between daily milk production in the 2nd and 10th month in milk. The cows were divided into three groups according to lactation persistency (decrease in production): group I – up to 30%, group II – 30.1–50% and group III – over 50%. Lactation persistency significantly influenced (P≤0.01) length of life and efficiency of milk production in the analysed cow population. Cows with yield over 30 kg at the peak of lactation followed by a moderate decrease (40%) lived longest (over 6 years) and produced the most milk (nearly 28,000 kg). Yield of primiparous cows at the peak of lactation and its course were found to have a significant effect on length of life and lifetime milk production. The long period of high peak yield (over 30 kg of milk) in the primiparous cows in group I (with the best lactation persistency) in the long term proved to be detrimental, as these cows had the shortest productive life (2.3 lactations on average) and lifetime milk yield about 4,000 kg lower than in the cows in groups II and II (with the poorer lactation persistency).

Length of Life and Milk Production Efficiency in Cows with Varying Lactation Persistency

Department of Breeding and Protection of Cattle Genetic Resources, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland

Annals of Animal Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

A total of 2,484 lactations in 760 Polish Holstein-Friesian cows were analysed. Calculations were made of length of life, length of productive life, total...

Length of Life and Milk Production Efficiency in Cows with Varying Lactation Persistency

Published Online: Aug 02, 2016

Page range: 851 - 862

Received: Aug 20, 2015

Accepted: Dec 22, 2015

DOI: https://doi.org/10.1515/aoas-2015-0088

Keywords
dairy production, lactation persistency, length of cows’ life, lifetime milk yield

© 2016 Zygmunt Litwińczuk et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Length of Life and Milk Production Efficiency in Cows with Varying Lactation Persistency

Published Online: Aug 02, 2016

Page range: 851 - 862

Received: Aug 20, 2015

Accepted: Dec 22, 2015

DOI: https://doi.org/10.1515/aoas-2015-0088

Keywordsdairy production, lactation persistency, length of cows’ life, lifetime milk yield

© 2016 Zygmunt Litwińczuk et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
dairy production, lactation persistency, length of cows’ life, lifetime milk yield