No abstract

The aim of the study was to evaluate herbage dry matter intake in 16 beef cows which grazed continuously on permanent pastures within the "The Warta Estuary" National Park (Poland), using the minimally invasive method based on n-alkanes as markers (C 29 , C 31 , C 33 ). Significant differences were observed in the nutritive value of herbage collected for analyses by cutting or nipping. The calculated content of energy and protein in the nipped herbage was higher: UFL by 58.1% and PDI by 50%, with a higher digestibility of nutrients. The values obtained for DM intake in pasture herbage by cows were closest to the standards when calculations were based on the C 29 /C 32 pair of n-alkanes. However, the best prediction of DM intake estimation from creeping bentgrass (Agrostis stolonifera) pasture, in agreement with the accepted energy and protein standards, was based on the proportions between alkanes C 31 /C 32 .

206E. Wojtas et al.: Colostrum feeding and the levels of protein fractions in calves' serum, Mljekarstvo 69 (3), 206-210 (2019) scientiFic note | AbstractThe aim of this study was to investigate the impact of additional colostrum feeding to new born calves on levels of selected serum protein fractions. The study was conducted on a commercial dairy farm. Twenty-four cows of Polish Holstein-Friesian breed and their calves were included in the trial. Chemical composition, the somatic cell count (SCC), the total bacteria count (TBC) and immunoglobulin G (IgG) concentration were determined in colostrum samples. Blood was collected via jugular vein puncture from a total of 24 calves at the 36 th hour of life. Total serum protein (TSP), as well as its fractions (albumins, globulins) and IgG concentration were determined. Greater IgG, total protein, albumins and globulins concentrations were found in serum of calves fed colostrum four times compared with three times on the first day of life. It was concluded that increasing the number of colostrum feedings to four times can be beneficial to forming of passive immunity of newborn calves.