Milk and serum samples from 35 dairy herds in 17 states were evaluated for cow- and herd-level Mycobacterium avium subspecies paratuberculosis (MAP) antibody test agreement. Evaluation of 6,349 samples suggested moderate agreement between milk and serum enzyme-linked immunosorbent assay (ELISA) results, with a kappa value of 0.50. Cow-level sensitivity (Se) for 18 dairy operations with 1,921 an...

The overall object of this research was to characterize US Holstein (virgin) heifer fertility. This included investigation of factors influencing heifer fertility and estimation of heritability, as well as correlations with cow fertility and first-lactation milk yield. A secondary objective was to compare linear and logistic model estimates of fixed effects and linear and threshold model estima...

The aim of this study was to identify the deficiency of uridine monophosphate synthase (DUMPS) and the complex vertebral malformation (CVM) in Iranian Holstein bulls. A total of 144 blood samples were prepared of Holstein bulls in Abbas Abad Animal Breeding Center and Ferdowsi University of Mashhad's Dairy Farm in Khorasan state of Iran. Genomic PCR-RFLP protocol was performed to amplify the po...

placental lactogen is a polypeptide hormone that is produced by the placenta, also known as chorionic somatomammotropin hormone. it has both growth hormone and prolactin activities on growth, lactation, and luteal steroid production. the objective of this study was to investigate the bovine placental lactogen (bpl) gene polymorphism of holstein cows in razavi khorasan province. blood samples we...

A 3-year-old Holstein-Friesian cow was evaluated because of sudden onset of right hind limb lameness and pain with fetlock swelling for 2 days. Based on the history, clinical index scores and computed radiographic examinations, the case was accurately diagnosed to be a severely comminuted fracture of the proximal phalanx. This cow was assigned for conservative treatment with external coaptation...

A 6-year-old lactating Holstein cow with a history of repeat breeding syndrome (failed to conceive afterthree artificial inseminations (AI) with fertile semen) was referred to the Veterinary Teaching Hospital of theSchool of Veterinary Medicine, Shiraz University. According to the history, neither abnormal clinical signs,nor uterine discharge had been observed subsequent to AI. The cow had show...

Polymorphism of the b-lactoglobulin (b-LG) gene in 101 cows belonging to the Holstein herd and a superior cow, producing more than 150 Kg milk/day, together with four offsprings was investigated by the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. In the Holstein herd, the alleles A and B of the b-LG gene had frequencies of 0.53 and 0.47, respectively. Th...

Introduction Investigating and comparing the two systems Comparing some technical efficiency ratios and profit Points to note about the comparison Conclusions References Abstract. In this study, budgets of herd dynamics, feed and energy supply, production and profit of alternative dairy farm systems were used to examine the effects of changing a 230 cow Holstein-Friesian (HF) dairy system to a ...