This paper describes the particularities of the anatomy and morphology of the dairy sheep udder and the current implications on machine milkability. The sheep mammary gland is an exocrine epithelial gland mainly constituted of tubulo-alveolar parenchyma with alveoli and well differentiated cisterns. Two anatomical compartments are used for milk storage: alveolar and cisternal, the large-cistern...

This work presented economic weights (EWs) calculated for Holstein cattle raised in Slovak dairy productions using a bio-economic approach. EWs are calculated for alternatives with (A) and without (B) market quota. Both alternatives included three market payment systems of milk (base price per milk value was corrected according to content of fat, protein and somatic cells). Marginal EWs for mil...

KULIG, H., K. ŻUKOWSKI, I. KOWALEWSKA-ŁUCZAK and P. ŁAKOMY, 2016. SCD1 polymorphism and breeding value for milk production traits in cows. Bulg. J. Agric. Sci., 22: 131–134 The aim of this study was to estimate the associations between the g.10153G>A polymorphism and the breeding values for milk production traits (milk, fat and protein yield, fat and protein content) in Polish Holstein-Friesian...

Selection for breeding animals as parents of next generation, based on genetic analyses of most important traits, became a standard for selection practices in most of the farm animal species in Slovakia. In this respect, about ten years of experience could be traced in Slovakian dairy cattle (Candrák et al., 1997) and pigs (Groeneveld and Peškovičová, 1999 and Peškovičová et. al., 1999). First ...

Positional, comparative candidate gene analysis and previous quantitative trait loci linkage mapping results were used to search for candidate genes affecting milk production and reproduction traits in dairy cattle. The protease inhibitor (PI) gene was chosen for examination, and 5 single nucleotide polymorphisms were detected in coding regions of the gene by direct sequencing of reverse transc...

Sequence variations in the bovine growth hormone (GH) gene were investigated by single strand conformation polymorphism (SSCP) analysis of seven amplified fragments covering almost the entire gene (2.7 kb). SSCPs were detected in four of these fragments and a total of six polymorphisms were found in a sample of 128 Holstein bulls. Two polymorphisms, a T-->C transition in the third intron (desig...

Co-expression network analyses provide insights into the molecular interactions underlying complex traits and diseases. In this study, co-expression network analysis was performed to detect expression patterns (modules or clusters) of microRNAs (miRNAs) during lactation, and to identify miRNA regulatory mechanisms for milk yield and component traits (fat, protein, somatic cell count (SCC), lact...

Daily milk, fat and protein yield and amount of somatic cells in cow milk are very important factors that influence milk performance traits. An association between polymorphisms in the kappa casein (CSN3) gene and milk production, composition and technical properties has been previously reported; however, this type of information is not available for the bovine β-carotene oxygenase 2 (BCO2) gen...

Background: The bovine AGPAT6 gene is one of the potential candidate genes governing milk fat synthesis.Objectives: Identification of single nucleotide polymorphisms (SNP) in the targeted region of AGPAT6 gene and their effect on expected breeding values (EBV) of first lactation milk production traits viz. fat %, fat yield and 305 days milk yield in Karan Fries (KF) breeding bulls were so...

The effects of inbreeding, heterosis, recombination loss, and percentage Holstein on the estimation of predicted transmitting abilities for fertility traits (calving interval, number of days from calving to first insemination, nonreturn rate, number of inseminations) and correlated traits (milk yield at test nearest d 110 and body condition score) were examined in a mixed population of Holstein...