Ceyhan Özbeyaz

Identification of factor XI deficiency in Holstein cattle in Turkey

BackgroundFactor 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.MethodsIn 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 cows. Amplicons of FXI exon 12 were obtained by Polymerase Chain Reaction (PCR), and analyzed by 2% agarose gel electrophoresis stained with ethidium bromide. Additionally, all cows were confirmed by DNA sequencing to determine whether or not there was a mutant allele.ResultsCarriers of the FXI deficiency have two DNA fragments of 320 bp and 244 bp in size. The results of our study demonstrated that only four out of the 225 Holstein cows tested in Turkey carried the FXI deficiency. The frequency of the mutant FXI allele and the prevalence of heterozygous cows were found as 0.9% and 1.8%, respectively.ConclusionThe DNA-based test determines all genotypes, regardless of phenotype or FXI activity. The mutation responsible for the FXI deficiency had not been detected in Holstein cattle in Turkey before prior to this study. The frequency of the mutant FXI allele needs to be confirmed by carrying out further analyses on cattle in Turkey and the selection programs should be developed to eliminate this genetic disorder.

Genetic diversity and divergence of some Swiss brown cattle herds in Turkey.

INTRODUCTIONThe Swiss Brown from Germany (German Brown) and the Austrian Swiss Brown(Montafoner) were imported after World War I to upgrade Turkish cattle for milkproduction. Pure-bred herds are maintained at government farms. These breedsand their crosses to the native cow now account for nearly 3% of the nationalherd.A primary objective of genetic conservation schemes is the maintenanceof maximum genetic variation within species. In livestock species, this can beachieved by the preservation of breeds (Hall and Bradley, 1995). The level ofgenetic differentiation among Swiss Brown subpopulations will depend on theunderlying population structure and the amount of migration between them. Thelonger the time populations have remained isolated, the greater will be the geneticdifferentiation due to genetic drift, particularly if the effective population size hasbeen small. However, the significant level of importation of Swiss Brown intoTurkey would suggest that Swiss Brown herds may be becoming genetically morealike.Very little is known about genetic diversity and population structure ofSwiss Brown cattle in Turkey. The objectives of this study were to determinepopulation structure and to assess the level of genetic differentiation betweensubpopulations of some Swiss Brown in Turkey by using blood proteinpolymorphisms.

Gene expression levels in some candidate genes for mastitis resistance, milk yield,and milk quality of goats reared under different feeding systems

* Correspondence: unaln@ankara.edu.tr