The number of dermal mast cells in several European and Zebu cattle breeds was determined and correlated with the tick load. Breeds included European registered and non-registered Holstein, Brown-Swiss and Jersey cows, Zebu (Nelore and Gyr) and crossbred cows with either high or low tick infestations. Animals were naturally infested with Rhipicephalus (Boophilus) microplus and evaluated at regu...

The traits particularly important for milk production include milk yield, protein percentage, fat percentage, and the somatic cell score. Alpha-lactalbumin (α-LA) is an important whey protein of cow milk, and is also present in the milk of many other mammalian species. In this study, we analyzed the genetic polymorphisms of the α-LA gene and their relationship to milk production traits (milk yi...

This study was conducted to investigate the effect of the interval between the onset of spontaneous estrus and artificial insemination (AI) on reproductive performance and calf sex ratio in repeat breeder Holstein cows. Two hundred eighty lactating Holstein cows were used in this study. The animals were artificially inseminated at different times (0–6, 7–12, 13–18, or 19–24 h) after the onset o...

The aim of this paper was to determine effects of selected genetic and environmental factors on the concentration of acetone in blood of cows in the first trimester of lactation. The study included 124 Polish Holstein-Friesian primiparous cows born, reared and managed on the same farm. The samples of blood were collected on day 2, 5, 30, 60 and 90 after calving. The highest serum acetone concen...

The study was conducted to know the effect of flushed feeding on estrus synchronization and conception rate of Holstein ÍLocal crossbred cow’s after using the GnRH (fertagyl) and PGF2α hormone. As a representative sample 20 Holstein ÍLocal crossbred cows were chosen from Chittagong Cantonment Military Dairy Farm in Bangladesh and the experimental work was carried out for 60 days. Ten cows were ...

Data from 113 Dutch organic farms were analysed to determine the effect of cross-breeding on production and functional traits. In total, data on 33 788 lactations between January 2003 and February 2009 from 15 015 cows were available. Holstein-Friesian pure-bred cows produced most kg of milk in 305 days, but with the lowest percentages of fat and protein of all pure-bred cows in the data set. C...

We conducted three experiments to determine the influence of mechanical processing on corn silage utilization by lactating dairy cows. Total mixed rations contained either unprocessed or processed corn silage harvested between 1/4 and 3/4 milk line. In trial 1, 12 multiparous Holstein cows were used in a replicated double switchback design with 21-d periods. Intake of dry matter (DM) was increa...

Genetic and phenotypic performance of U.S. Holstein embryo-split and nuclear-transfer clones was documented for yield and fitness traits. For cows, mean genetic superiority based on pedigree was 186 kg of milk, 9 kg of fat, and 7 kg of protein for embryo-split clones and 165, 10, and 8 kg, respectively, for nuclear-transfer clones compared with the population for the same birth year; pedigree a...

Th e aim of this study was to establish the prevalence of repeat breeder syndrome (RBS) in diff erent breeds and reproductive ages of cattle in central Croatia and to assess the eff ectiveness of hormone therapy as a treatment option. A total of 1088 dairy cows were observed, 218 heifers and 870 multiparous cows. Aft er the third unsuccessful artifi cial insemination (n = 164) and a thorough cl...

Efficacy study of GALACTIN VET Bolus (5 boli once daily for 10 days) was conducted in moderate milk producing Holstein and Jersey crossbred cows. Improved milk yield, CLR, Fat % and SNF % supported GALACTIN VET bolus to be safe galactagouge in dairy cows.