The objective of this study was to investigate the effect of inbreeding on lactation performance in Holstein cows of Iran.The pedigree file contained information of 1,025,281 animals born between 1965 and 2007.Lactation performance records from March 2000 to April 2009 comprising 193,501calving events on 123,751 cows in 85 dairy herds were included in the data set. The potential consequent effe...

Connecting genome-wide association study (GWAS) to biological mechanisms underlying complex traits is a major challenge. Mastitis resistance and milk production are complex traits of economic importance in the dairy sector and are associated with intra-mammary infection (IMI). Here, we integrated IMI-relevant RNA-Seq data from Holstein cattle and sequence-based GWAS data from three dairy cattle...

no. 424; Session G4.44 [email protected] EFFECT OF SMALL-HERD CLUSTERING ON THE GENETIC CONNECTEDNESS OF THE PORTUGUESE HOLSTEIN CATTLE POPULATION J.Vasconcelos and J.Carvalheira Centro Investigação em Biodiversidade e Recursos Genéticos (CIBIO), Universidade do Porto, Rua Padre Armando Quintas, 4485-661 Vairão, PORTUGAL, ICBAS-Universidade do Porto INTRODUCTION Accuracy of genetic evaluat...

Mycoplasma bovis (M. bovis) is a highly infectious pathogen of cattle causing pneumonia, polyarthritis, otitis, and less frequently, subcutaneous abscesses, abortions and meningitis. Ineffective drugs treatments, culling of infected cows and loss of milk production can lead to significant economic loss on dairy farms. The early detection of cows excreting M. bovis bacteria to prevent mastitis o...

This study describes the clinical, histopathological, and virological characterization of teat papillomatosis from Brazilian dairy cattle herds. Four types of bovine papillomavirus were identified (BPV6, 7, 9, and 10); one of these (BPV7) is being detected for the first time in Brazilian cattle.

In this study, the presence of antibodies to Brucella abortus, Chlamydophila abortus, Coxiella burnetii, Bovine herpesvirus-1 (BHV-1), Bovine viral diarrhea virus (BVDV) and Bovine herpesvirus-4 (BHV-4) were investigated in dairy cattle herds with abortion history in Burdur province, Southwest region of Turkey. The blood samples were collected from 932 dairy cattle ≥2 years of age from 10 herds...

calving records from april 1998 to september 2006 comprising 104,572 calving events from 16 dairy herds of iran were used to analyze the potential effect of dystocia on calf stillbirth and productive traits in iranian holsteins. statistical analyses of production traits were performed using a linear mixed model procedure. also, a logistic regression model was constructed to analyze the effect o...

The objective of this research was to determine the prevalence, risk factors and consequent effect of dystocia on lactation performance in Holstein dairy cows in Iran. The data set consisted of 55,577 calving records on 30,879 Holstein cows in 30 dairy herds for the period March 2000 to April 2009. Factors affecting dystocia were analyzed using multivariable logistic regression models through t...