Quantitative traits locus for milk production traits has been described on centromeric end of bovine chromosome 14. Reports name the acyl coA: diacylglycerol acyltransferase (DGAT1) gene as a potential candidate gene with dinucleotide substitution (AA to GC) in exon VIII which causes the change of lysine to alanine in amino acid (K232A).The aim of the present study was to estimate the frequency...

This study was conducted at the National Artificial Insemination Center, Ethiopia with an objective of evaluating breeding soundness, effect of age and breed on semen quality and fertility of bulls. The evaluation involved 45bulls (36 breeding and 11 pre-service young bulls) consisting of Holstein Friesian, Jersey, Borana and Cross breeds (Borana X Holstein Frisian). Semen was collected using a...

Sperm DNA damage affects the conception rate resulting from human assisted reproduction technology. The objective of this study was to adapt the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay to provide a quality parameter for bull semen based on the detection of sperm DNA damage. Fresh semen was collected from two Japanese Black bulls (A, B) several times o...

quantitative traits locus for milk production traits has been described on centromeric end of bovine chromosome 14. reports name the acyl coa: diacylglycerol acyltransferase (dgat1) gene as a potential candidate gene with dinucleotide substitution (aa to gc) in exon viii which causes the change of lysine to alanine in amino acid (k232a).the aim of the present study was to estimate the frequency...

Many factors affect ruminant carcass and meat quality, and among the genetic and environmental factors, feeding plays an important role in the determination of quality. In a large study, sixty-four German Holstein and German Simmental bulls were randomly allocated to either an indoor concentrate feeding system or periods of pasture feeding following by a finishing period. During this period the...

the holstein bulls (n=50) were genotyped for bovine lymphocyte antigen (bola-drb3.2) alleles by polymerase chain reaction and restriction fragment length polymorphism (pcr-rflp). genomic dna was extracted from bull semen using phenol-chloroform method. a two-step pcr was conducted in order to amplify a 284 base-pair fragment of the target gene. amplicons were digested by rsai, haeiii and bstyi ...

The availability of genomic evaluations since 2008 has resulted in many changes to dairy cattle breeding programs. One such change has been the increased contribution of young bulls (0.8 to 3.9 yr old) to those programs. The increased use of young bulls was investigated using pedigree data and breeding records obtained from the US national dairy database (Beltsville, MD). The adoption of genoty...

An experiment was conducted to determine the effects of long-term feeding of cottonseed meal on the reproductive traits of Holstein bulls. Holstein bulls approximately 6 mo of age were placed on the following treatments: 1) soybean meal + corn (CON); 2) cottonseed meal + corn (GOS); and 3) cottonseed meal + 4,000 IU vitamin E x bull(-1) x d(-1) (G+4E). The GOS and G+4E diets were formulated to ...

Transition protein 2 (TNP2) participates in removing nucleohistones and the initial condensation of spermatid nucleus during spermiogenesis. This study investigated the relationship between the variants of the bovine TNP2 gene and the semen quality traits of Chinese Holstein bulls. We detected three single nucleotide polymorphisms (SNPs) of the TNP2 gene in 392 Chinese Holstein bulls, namely, g...