The aim of this study was to evaluate possible associations between three SNPs at the oxytocin locus (AM234538: g.28C>T; g.204A>G and g.1627G>T) and two productive traits, milk yield and milkability, in Italian Mediterranean river buffaloes. Effects of parity, calving season and month of production were also evaluated. A total of 41 980 test-day records belonging to 219 lactations of 163 buffal...

Intensive selection of sires is possible by using artificial insemination; coupled with accurate measurement of a potential sire’s genetic value, this has markedly improved genetics for easily measured traits like milk production and type traits. Increased milk production has in turn increased gross feed efficiency through dilution of maintenance. Additional genetic gains in feed efficiency wou...

The relationship between the SNP of the cytochrome P450 gene (CYP19-PvuII) and milk production traits of Black-and-White and Jersey cattle were analysed. A total of 437 cows were included in the study. A PCR-RFLP was used to genotype. The frequencies of genotypes and alleles for the Black-and-White cows were as follows: 0.8985 AA, 0.0977 AB, 0.0038 BB, and 0.9474 CYP19, 0.0526 CYP19. In the Jer...

We have used the results of an experiment mapping quantitative trait loci (QTL) affecting milk yield and composition to estimate the total number of QTL affecting these traits. We did this by estimating the number of segregating QTL within a half-sib daughter design using logic similar to that used to estimate the "false discovery rate" (FDR). In a half-sib daughter design with six sire familie...

the milk and milk fat production records of 28 holstein herds in khorasan razavi province were analyzed in this study. the records were based on 305 days of milking and were from the first to third milking periods and two times milking per day. the fixed effects of herd-year-season and age of dam at parturition as covariate were fitted in the models of analyses. the (co)variance components were...

The objective of this study was to assess the association of polymorphisms in κ-cn, β-lg, β-lg 5′ flanking region, CSN1S2, and IGFBP-3 genes with milk production traits and mastitis-related traits in Chinese Holstein. Traits analyzed were 305 day standard milk yield, protein percentage, fat percentage, the ratio of fat percentage and protein percentage, pre-somatic cell count, somatic cell coun...

Cow milk is a rich source of protein and selected micronutrients such as calcium. Recently, a relationship between disease risk and consumption of a specific bovine β-casein fraction either A1 or A2 genetic variants has been identified. Polymorphism at codon 67 of the beta-casein gene: CCT→CAT causes a substitution of amino acid proline (in A2 variant) by histidine (in A1 variant). The presence...

BACKGROUND 5,10-Methylenetetrahydrofolate reductase (MTHFR) plays a central role in folate metabolism by irreversibly converting 5,10-methylenetetrahydrofolate to 5-methylenetetrahydrofolate, a predominant circulating form of folate. Folate is reportedly important for milk protein synthesis, and MTHFR may be a key regulatory point of folate metabolism for milk protein synthesis in mammary epith...

The objectives of the study were to estimate genetic parameters for milk production traits of Holstein cattle using random regression models (RRMs), and to compare the goodness of fit of various RRMs with homogeneous and heterogeneous residual variances. A total of 126,980 test-day milk production records of the first parity Holstein cows between 2007 and 2014 from the Dairy Cattle Improvement ...

in order to estimate the genetic parameters and comparison legendre polynomials for production traits of iranian holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. these records collected from 2006 to 2010, by the animal breeding center of iran. the genetic parameters were estimated usi...