Przeglądaj wg Autor "Pankowski, Mateusz"

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  • Miniatura
    PozycjaOpen Access
    Daily activity of polish holstein-friesian cows depending on variable housing conditions during lactation
    (Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2017) Mróz, Piotr; Wójcik, Piotr; Pankowski, Mateusz; Faculty of Animal Science, Warsaw University of Life Sciences; Department of Animal Genetics and Breeding, National Research Institute of Animal Production, Balice; Alta Polska Ltd., Łowicz
    The aim of the study was to analyse the activity of Polish Holstein-Friesian cows depending on variable housing conditions during lactation, associated with short-term (30-day) reduction in the living area. The study used two groups of cows (25 animals per group) housed in sections with or without an outdoor area and subjected to temporary (30-day) crowding as well as one group of cows subjected to decreasing stocking density. All animals were fitted with pedometers on the hind legs, which recorded data on activity (steps/hour), resting frequency (times per day), resting bout duration (minutes), and total resting time (minutes). Activity analysis of the groups performed before the change in stocking density showed that in the group of cows without outdoor access, fourth lactation cows (175.59 steps/h) and primiparous cows were the most active (147.09 steps/h). Primiparous cows rested most frequently (14.14) and showed longest total resting time (588.73 min). In the group with outdoor access, significantly highest activity was shown by primiparous cows (132.18 steps/h) and lowest activity by fourth lactation cows (108.92 steps/h). Fourth lactation cows were also characterized by lowest resting frequency (8.41) and lowest total resting time (525.16 min), as well as longest resting bout (74.91 min). Following the first increase in stocking density, the group of cows without outdoor access showed very high activity (133.65 steps/h), and the cows with outdoor access reduced their activity. The next increase in stocking density caused the confined cows to increase their activity, which was associated with increasing stress, while the group of cows with outdoor access did not respond with higher activity but the duration of resting bout increased (61.16 min) and its frequency decreased. As a result, total resting time was shorter than in the group without outdoor access. In the group without outdoor access, rests were less frequent but longer (59.91 min), which could be due to the difficulty finding a place to rest. In all the study groups, total resting time decreased to an unprecedented time of less than 490 min.
  • Miniatura
    PozycjaOpen Access
    The Use of Lactation Persistence as an Indicator in the Selection of the Maternal Lines of HF Cows
    (Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2022) Wójcik, Piotr; Cwynar, Marzena; Pankowski, Mateusz; National Research Institute of Animal Production, Department of Cattle Production, Poland; Kombinat Rolny Kietrz Ltd., Poland; Alta Genetics Ltd., Poland
    The research material for this study consisted of a group of 163 Polish Holstein Friesian cows (PHF). For the study, the cows were assigned to 14 maternal lineages covering three generations. The aim of this study was to indicate possibilities for selecting cows with the goal of maintaining lineages on the farm which are characterised high productive qualities based on lactation persistency index. Basic milk parameters were analysed over a 305-day lactation cycle and information on somatic cell content was also gathered based on sample milkings. A characterisation of lactation persistency for a given lactation was generated as a percent difference between milk yield in the 2nd and 10th month of lactation, and a lactation persistency curve was developed for particular lineages in successive lactations, representing changes in the productivity of the cows. It was determined that together with increasing numbers of lactations among the cows studied, the average lactation persistency index also increased. For younger cows, this index did not exceed 30%, while in the older group this index amounted to 70%. Cows with the highest lactation persistency values 70.1–80% were also characterised by the highest milk production in average daily milk yields during peak lactation, amounting to 56.14 kg at values of for the index. Cows which began their milk production stage with a high persistency index in the 1st and 2nd lactations, in successive lactations saw a significant decrease in this index. Breeding cattle within maternal lines characterized by a high and stable level of lactation persistence index can ensure a high level of milk production in this line of cows.