FPUTS seria Agricultura, Alimentaria, Piscaria et Zootechnica, 2022

Stały URI zbioru

https://oa.zut.edu.pl/handle/20.500.12539/762

Przeglądaj

Przeglądaj FPUTS seria Agricultura, Alimentaria, Piscaria et Zootechnica, 2022 wg Autor "Antkowiak, Ireneusz R."

Teraz wyświetlane 1 - 2 z 2
  • Miniatura
    PozycjaOpen Access
    Characteristics of Reproduction Traits in Cows with Record Lifetime Milk Yields
    (Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2022) Pytlewski, Jarosław; Antkowiak, Ireneusz R.; Czerniawska-Piątkowska, Ewa; Department of Animal Breeding and Product Quality Assessment, Poznań University of Life Sciences, Poznań, Poland; Department of Animal Breeding and Product Quality Assessment, Poznań University of Life Sciences, Poznań, Poland; Department of Ruminant Science, West Pomeranian University of Technology, Szczecin, Poland
    The aim of this study was to characterise basic reproduction indexes and to investigate the effect of selected factors on values of analysed fertility parameters in cows (100 head) with record lifetime milk yields. The experiments were conducted on Polish Holstein-Friesian Black- -and-White cattle. Cows with lifetime milk yields of min. 100 thousand kg milk were considered record holders. Animals were selected at random from herds covered by performance testing in the Poznań testing region in the years 2003–2016. It was shown that analysed cows with record lifetime milk yields exhibited slightly reduced fertility. The animals had the preferred mean age at first calving and adequate average length of pregnancy. Relatively high numbers of semen doses required for successful insemination resulted in an extended length of calving interval, interpregnancy period and artificial mating service.In the management of dairy cow herds focusing on high lifetime productivity and fertility traits it is recommended to control reproduction so that calvings take place in winter and cows calve for the first time at the age of maximum 27 months.
  • Miniatura
    PozycjaOpen Access
    The Effect of Selected Factors on Milking Rate in Polish Holstein-Friesian Black-And-White Cows.
    (Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2022) Pytlewski, Jarosław; Antkowiak, Ireneusz R.; Czerniawska-Piątkowska, Ewa; Department of Animal Breeding and Product Quality Assessment, Poznań University of Life Sciences, Poznań, Poland; Department of Animal Breeding and Product Quality Assessment, Poznań University of Life Sciences, Poznań, Poland; Department of Ruminant Science, West Pomeranian University of Technology, Szczecin, Poland
    The aim of the study was to investigate the effect of selected physiological factors (age, lactation stage and daily milk yield) on milking rate by Polish Holstein-Friesian Black-and-White cows. The duration of morning, evening and diurnal milking was determined. Milking rate of cows was char acterized based on the mean actual and corrected milk yield per 1 minute of milking. Statistical analy sis showed a lack of any dependence between the age group of cows and milking duration as well as mean actual and corrected milk yields in the minute of milking. Milking time decreased with progress in lactation. In terms of the mean milk yield the lowest value of this parameter was recorded for cows being in their first stage of lactation (≤ day 40). Cows with greater daily milk yields compared to those producing less milk were characterized by longer milking times and greater mean actual and corrected milk yields in the minute of milking. Milking rate of cows is a functional trait of considerable importance in the economics of raw milk production. The selection towards of an increase in milk yield, may have a positive effect on milking rate in cows.