Sire genetic evaluations for protein yield, somatic cell score (SCS), productive life, and udder type traits from the US were correlated with sire evaluations for udder health from Denmark and Sweden and then the correlations were adjusted for accuracies to approximate genetic correlations. Traits from Denmark and Sweden included somatic cell count (SCC) and clinical mastitis from single-trait ...

The present study was intended to estimate the prevalence of subclinical mastitis (SCM) in apparently healthy dairy goats, to carry out culture sensitivity of isolated pathogens and to elucidate the associated risk factors of mastitis. A total of 200 goats comprising of 397 udder halves from 10 flocks of Punjab was carried out. Milk samples from were collected and screened for California Mastit...

Once daily milking reduces milk yield, but the underlying mechanisms are not yet fully understood. Local regulation due to milk stasis in the tissue may contribute to this effect, but such mechanisms have not yet been fully described. To challenge this hypothesis, one udder half of six Holstein dairy cows was milked once a day (ODM), and the other twice a day (TDM). On the 8th day of unilateral...

Four cows received thyroxine injections (T4; 20 mg/d) and three cows received growth hormone injections (GH; 44 mg/d) for 4 d during successive 16-d experimental periods. Measurement was made of milk yield, protein yield, mammary tyrosine and phenylalanine uptake, blood plasma hormone concentrations, mammary blood flow and cardiac output. Milk yield increased by 25% with T4 and 21% with GH trea...

We examined the repertoire and extent of inflammation dependent gene regulation in a bovine mammary epithelial cell (MEC) model, to better understand the contribution of the MEC in the immune defence of the udder. We challenged primary cultures of MEC from cows with heat inactivated Escherichia coli pathogens and used Affymetrix DNA-microarrays to profile challenge related alterations in their ...

Dolly was the first cloned mammal and must be the most famous sheep in the world. Two things made her famous: first that she is an artificially induced clone, genetically identical to a previously existing sheep, for Dolly can be thought of as a vertical twin with identical genes, in this case to the parent. Second is the way in which it was done. The scientists took the nucleus from a cell fro...

In this study we aimed to evaluate the reduction in dimensionality of 20 linear type traits and more final score in 14,943 Holstein cows in Brazil using factor analysis, and indicate their relationship with longevity and 305 d first lactation milk production. Low partial correlations (-0.19 to 0.38), the medium to high Kaiser sampling mean (0.79) and the significance of the Bartlett sphericity ...

Recognition of Mycoplasma-induced mastitis is on the increase. Although Mycoplasma bovis is identified as the causative agent in more than 50 per cent of the mastitis cases, seven other Mycoplasma species have also been isolated. The mycoplasmas are commonly found in the microflora of the respiratory and urogenital tracts of normal cattle, where precipitating factors can initiate their role as ...

Genetic relationships between yield and type traits were investigated using multiple-trait REML procedures with an animal model. Computing strategies were developed to deal with large populations and numbers of traits. Data consisted of records for 3 production and 15 type traits for 20,836 primiparous cows from 1982 to 1988. The model included 2358 herd management effects, 28,749 animal effect...