The objective of this study was to investigate the effect of a partial substitution of soybean meal with field pea (Pisum sativum) in Holstein lactating dairy cow diets on dry matter intake, milk yield and composition, blood metabolites, rumen ammonia-N concentration and pH. Eighteen lactating Holstein cows were randomly assigned into three groups based on parity, days in milk, and mil...

In this study, the relationships and correlations between milk production and some blood metabolites related to energy and protein balance and their effects were investigated on returning to estrus after AI in lactating Holstein dairy cows. Blood and milk samples were collected from sixty lactating Holstein dairy cows based on their reproductive status in 13-17 d post AI. BUN, MUN, glucose, tri...

Genetic evaluations of Holstein bulls for mean somatic cell score were compared with their standardized transmitting abilities for linear type traits. Based on first lactation daughter information from five dairy records processing centers, PTA for somatic cell scores for 712 sires ranged from -.50 to .56. Standardized transmitting abilities for 14 type traits were provided for these bulls by t...

The objective of this study was to determine how the concentration of milk urea (MU) and FPCM production affect reproduction in selected Holstein dairy herds in the Czech Republic. A retrospective, observational study comprising analyses of individual cow records from monthly dairy herd improvement (DHI) milk tests including milk urea (MU) concentration was conducted in six commercial Holstein ...

BACKGROUND The milk yield can be affected by the frequency of milking per day, in dairy cows. Previous studies have shown that the milk yield is increased by 6-25 % per lactation when the milking frequency is increased from 2 to 3 times per day while the somatic cell count is decreased. To investigate the effect of milking frequency (3X vs. 4X) on milk yield and it's genetic parameters in the f...

Objective. To determine the associations of BoLA DRB3.2 alleles present in Holstein and BON x Holstein cattle to production and milk quality traits in a dairy herd of Antioquia, Colombia. Materials and methods. Ninety-one cows, 66 Holstein and 25 BxH, were genotyped for the BoLA DRB3.2 gene, through PCR-RFLP technique. Furthermore, the association of the alleles of the gene BoLA DRB3.2 with mil...

Twinning in Holstein dairy cows has increased over time concurrent with increased milk production. More than 95% of twins in Holsteins arise due to double ovulations resulting in dizygotic twins. It is now clear that low progesterone during growth of a preovulatory follicle increases the incidence of double ovulation. Increased hepatic metabolism of progesterone as a result of the increased fee...

Polymorphisms in the prion protein gene (PRNP) in humans and sheep correlate with susceptibility to transmissible spongiform encephalopathies (TSEs). Bovine spongiform encephalopathy (BSE) has been reported in British and Japanese cattle; it has occurred thus far in Holstein cattle. BSE in Hanwoo (Bos taurus coreanae) cattle has not been diagnosed up to now. To characterize the bovine PRNP poly...

The aim of this study was to assess the measurement of bone mineral density (BMD) by quantitative computed tomography (QCT), comparing the relationships of BMD between QCT and dual-energy X-ray absorptiometry (DXA) and between QCT and radiographic absorptiometry (RA) in the metacarpal bone of Holstein dairy cows (n=27). A significant positive correlation was found between QCT and DXA measuremen...

and Implications Lactating Holstein cows were assigned to 1 of 2 dietary iodine treatments at the Iowa State University Dairy farm. Objectives were to compare the bioavailability and production responses of an experimental product vs. an established iodine feed ingredient. The two commercial iodine sources were both fed at increasing doses. Results indicate a similar bioavailability between pro...