Abstract. Currently, extensive investigations are being carried out in the area of mitochondrial genomics. Mitochondrial DNA is used in many fields of science, e.g. evolutionism, phylogeography, anthropology, archaeology, forensics, medical diagnostics, veterinary medicine, molecular ecology, population genetics, and animal breeding. Mitochondrial markers, haplotypes, or haplogroups are associated with pathogenesis of diseases, evolution and origin of organisms, and identification of species. An interesting direction based on mitochondrial DNA sequences is the research into polymorphisms/mutations that can be related to economically important utility traits of livestock. The use of mtDNA has drawbacks due to the low power of discrimination and pattern of inheritance. Still, mtDNA has many advantages as a marker; therefore, it is often used in both basic and applied research.
Abstract. This study involved 1072 Polish Holstein-Friesian cows that were raised in 12 farms of the Kujawsko-Pomorskie province and culled between 2000 and 2012. Statistical calculations accounted for the effect of certain factors (age of cow at first calving, production level in the first lactation, housing system, herd size) on cow longevity (lifespan, length of productive life, number of calvings) and lifetime performance (GLM procedure of SAS) and proportion of culled cows (FREQ procedure of SAS). Increasing cow herd size had a negative effect (P ≤ 0.01) on longevity and lifetime performance. Likewise, efforts to maximize first lactation milk yield (> 10 000 kg milk) may shorten (P ≤ 0.05) the lifespan of the cows. Among the culled cows, as much as 90% were culled for reasons unplanned by breeders. Alarmingly, culling levels were particularly high (92%) in the largest herds (> 100 cows). Cows were culled mainly for infertility, and this reason for culling was particularly noticeable in cows that were oldest at first calving (> 30 months of age); yielded more than 10 000 kg of milk as primiparous cows; and were used in herds of 51–100 cows.
Abstract. The aim of this work was to demonstrate the periods of the increased demand on Ca, P and Mg in immature males of red deer. In blood serum concentrations of Ca2+, inorganic P and Mg2+ were evaluated using a spectrophotometric method. In the first autumn of life the highest concentrations were observed at the levels of: Ca – 2.858 ± 0.62 mmol × l-1; P – 2.617 ± 0.25 mmol × l-1 and Mg – 0.878 ± 0.09 mmol × l-1. In October the lowest concentration of Mg was noticed, reaching 0.584 ± 0.18 mmol × l-1, while in case of Ca and P the lowest concentrations occurred in second November of life, with the values of 1.406 ± 0.19 mmol × l-1 and 1.596 ± 0.28 mmol × l-1 respectively. The results show the validity of mineral supplementation in red deer males in the period of entering puberty, mainly because of Ca–P–Mg expenses related to skeleton growth and development of first antler. Application of mineral supplements in summer should reduce the risk of decrease in skeleton growth rate caused by antler mineralization in autumn.
Abstract. The study was conducted on 13 ram-lambs of Berrichon du Cher and 19 ram-lambs of Polish Merino in Grotkowo flock belonging to GRH Żydowo. The lambs were fed ad libitum using TMR. The lambs were slaughtered at a body weight 40 kg. The slaughter and carcass value and meat (mld) quality were estimated. Carcasses of Polish Merino lambs were in better fat class (in EUROP classification) compared to Berrichon du Cher. Higher levels of fat in Berrichon du Cher's carcasses would have an impact on higher weight of primary cuts compared to Polish Merino. The studies showed favorable level of physico-chemical characteristics and fatty acid profile of the meat (\emph{mld}) of Berrichon du Cher compared to Polish Merino. Intensive hausing system connected with feeding ad libitum (using TMR) causes a high level of fatness of carcasses of Berrichon du Cher rams. Although its carcasses characterized better pH24 and favorable fatty acid profile compared to Polish Merino. Taking into account the requirements of consumers, carcasses of rams fattened to a weight of 40 kg, may meet with difficulties in the disposal and therefore should be consider the wider use of Berrichon du Cher breed as a paternal breed in crossbreeding.
Abstract. The aim of this study was to illustrate the influence of the European beaver (Castor fiber) on the natural environment and economy using the data on the size and type of damages inflicted by these rodents within the boundaries of the Kuyavian-Pomeranian Voivodship over the years 2005-2013. The population of beaver in this area is estimated around 5 thousand. The most common damages include tree girdles, grassland flooding, arable crop damages, damages to dikes and fish pond embankments.
