The aim of the study was to investigate the dependencies between milking performance of cows at first lactation and their lifespan and lifetime yield. Investigations were conducted in a herd of Polish Holstein-Friesian black-and-white cows, located in the Wielkopolska region. Analyses were performed on cows culled in the years 2002-2007 (868 heads). Cows were kept in two loose box barns with straw-littered beds. Feed rations were established using the INRA program. Culled cows were characterised on the basis of the following parameters: lifespan, length of productive life, the number of days of the milking period, age at first calving, lifetime performance, lifetime yield per day of life, per day of productive life and per day of milking period. Lifetime performance of cows was expressed in kilograms of milk, fat corrected milk (FCM), of butterfat and of protein. In this study lifespan, length of productive life, length of milking period and lifetime milking performance of cows and milking performance per day of life, per day of productive life and per day of milking period were analysed depending on the milk yield in the first complete lactation expressed in kilograms of FCM. The longest lifespan, productive life and milking period were found for cows with the lowest milk yield in the first lactation. Cows with varied milking performance in the first lactation did not differ statistically significantly in lifetime productivity expressed in kilograms of milk, butterfat, protein and FCM. Milk yield, yields of butterfat, protein and FCM in cows per day of life, day of productive life and day of milking period increased with an increase in milk production in the first lactation.
|MLA||Pytlewski, Jarosław, et al. "Relationships between milking performance of cows in the first lactation and their longevity." Nauka Przyr. Technol. 4.1 (2010): #7.|
|APA||Jarosław Pytlewski, Ireneusz Antkowiak, Ryszard Skrzypek (2010). Relationships between milking performance of cows in the first lactation and their longevity. Nauka Przyr. Technol. 4 (1), #7|
|ISO 690||PYTLEWSKI, Jarosław, ANTKOWIAK, Ireneusz, SKRZYPEK, Ryszard. Relationships between milking performance of cows in the first lactation and their longevity. Nauka Przyr. Technol., 2010, 4.1: #7.|
Katedra Hodowli Bydła i Produkcji Mleka
Uniwersytet Przyrodniczy w Poznaniu
ul. Wojska Polskiego 71 A