Beef derived from Holstein steers is a significant source of the U.S. beef supply. The nation’s 9.1 million dairy cows in 2003 were 22% of the U.S. cow herd (NASS, 2005). Given the typical breed distribution of dairy cows, calving interval, full-term pregnancy rate, peri-natal calf death loss (NAHMS, 2002), gender distribution, dairy beef placement (80%) and survival to market (94%), it can be ...

the objective of this study was to investigate the effect of birth weight (bw) on future milk production and reproductive performance in iranian holstein cattle. records of holstein cows between 1967 and 2010 were obtained from the animal breeding center of iran. birth weights within each herd were grouped into five categories based on the standard normal distribution curves (z ≤-0.8416, -0.841...

Bovine genital campylobacteriosis is one of the most economically important diseases of dairy cattleresulting in lowered fertility, embryo mortality and abortion, repeated returns to service, reduced pregnancyrates and extended calving intervals. While the occurrence of repeat breeding syndrome and abortions arereported from many Iranian dairy cattle farms, little information is available regar...

The growth hormone receptor (GHR) is a member of cytokine/hematopoietin family that mediates the biological actions of growth hormone (GH) on target tissues. Therefore, the purpose of this study was to examine the association of TG-repeat polymorphisms in the 5’-flanking region of bovine GHR gene with milk production traits and somatic cell score (SCS) in Holstein cattle of Iran. The part of 5’...

Mastitis is one of the most serious and costly diseases affecting dairy cattle production. In the present study, effects of a lactoferrin gene polymorphism (intron 6) on milk somatic cell count (SCC) and subclinical mastitis was investigated in 121 Holstein dairy cattle. Two alleles of A and B and two genotypes of AA and AB were found in an EcoRI recognized single nucleotide polymorphism in int...

We sequenced exon 2 of the major histocompatibility complex (MHC) class II DRB3 gene from 471 individuals in four different Japanese populations of cattle (201 Japanese Black, 101 Holstein, 100 Japanese Shorthorn, and 69 Jersey cattle) using a new method for sequence-based typing (SBT). We identified the 34 previously reported alleles and four novel alleles. These alleles were 80.0-100.0% ident...

BACKGROUND Factor XI (FXI) is a plasma protein that participates in the formation of blood clots. Factor XI deficiency is autosomal recessive hereditary disorder that may be associated with excess bleeding in Holstein cattle. METHODS In this study, 225 Holstein cows reared in Turkey were screened in order to identify FXI genotypes. DNA extractions were obtained from the fresh blood of the cow...

in recent years, the relationship between insertion and deletion (indel) polymorphisms in promoter region (23 bp) and intron 1 (12 bp) of prnp gene (prion protein coding gene) and their relationship to susceptibility of classical bovine spongiform encephalopathy (bse) have been reported. insertions of these two polymorphisms increase resistance to classical bse, while the deletions of these two...