These favourable effects of comicronised fenofibrate both on lipid and non lipid parameters, including insulin sensitivity, may confer to this product a particular interest in the treatment of patients with polymetabolic syndrome X.

The objective of this study was to estimate heritabilities and genetic correlations of lactational and daily somatic cell scores with descriptive and linear type traits in Polish Holstein-Friesian cows. Data were: test-day somatic cell scores and conformation evaluations of 24 599 primiparous cows, daughters of 802 sires. Cows calved from 2006 to 2007. The lactational somatic cell score was calculated as the average of four test-day somatic cell scores at least. The daily somatic cell score was the test-day somatic cell score closest to the date of type evaluation. A multi-trait animal model was used to estimate genetic parameters. (Co)variance components were estimated by a Bayesian algorithm via Gibbs sampling. The heritability of lactational somatic cell score was 0.20 and it was much higher than that of daily somatic cell score (0.13). Heritabilities of type traits were high to moderate for height at rump (0.46), size (0.39), overall conformation score (0.30), two linear rump traits (0.28–0.29) and three linear teat traits (0.26–0.29). The genetic correlation between lactational and daily somatic cell scores was 0.84. In many cases, daily somatic cell score showed higher genetic correlations with type traits than lactational somatic cell score. Descriptive udder and feet and legs scores were genetically correlated negatively with both lactational (–0.22 and –0.20) and daily somatic cell scores (–0.28 and –0.33). Somatic cell traits were genetically correlated positively with rump angle (0.21 and 0.19) and negatively with fore udder height (–0.26 and –0.29), udder depth (–0.23 and –0.17) and central ligament (–0.14 and –0.16). Due to higher heritability, direct selection for lower lactational somatic cell score would be more effective than selection for lower daily somatic cell score. The magnitude of obtained heritabilities and the favourable genetic correlations indicate that the selection utilizing some type traits could improve the resistance to mastitis.

The aim of the study was to fit the genomic evaluation model to Polish Holstein-Friesian dairy cattle. A training data set for the estimation of additive effects of single nucleotide polymorphisms (SNPs) consisted of 1227 Polish Holstein-Friesian bulls. Genotypes were obtained by the use of Illumina BovineSNP50 Genotyping BeadChip. Altogether 29 traits were considered: milk-, fat- and protein- yields, somatic cell score, four female fertility traits, and 21 traits describing conformation. The prediction of direct genomic values was based on a mixed model containing deregressed national proofs as a dependent variable and random SNP effects as independent variables. The correlations between direct genomic values and conventional estimated breeding values estimated for the whole data set were overall very high and varied between 0.98 for production traits and 0.78 for non return rates for cows. For the validation data set of 232 bulls the corresponding correlations were 0.38 for milk-, 0.37 for protein-, and 0.32 for fat yields, while the correlations between genomic enhanced breeding values and conventional estimated breeding values for the four traits were: 0.43, 0.44, 0.31, and 0.35. This model was able to pass the interbull validation criteria for genomic selection, which indicates that it is realistic to implement genomic selection in Polish Holstein-Friesian cattle.Electronic supplementary materialThe online version of this article (doi:10.1007/s13353-011-0047-z) contains supplementary material, which is available to authorized users.

BackgroundLongevity expressed as the number of days between birth and death is a trait of great importance for both human and animal populations. In our analysis we use dairy cattle to demonstrate how the association of Single Nucleotide Polymorphisms (SNPs) located within selected genes with longevity can be modeled. Such an approach can be extended to any genotyped population with time to endpoint information available. Our study is focused on selected genes in order to answer the question whether genes, known to be involved into the physiological determination of milk production, also influence individual's survival.ResultsGenerally, the highest risk differences among animals with different genotypes are observed for polymorphisms located within the leptin gene. The polymorphism with a highest effect on functional longevity is LEP-R25C, for which the relative risk of culling for cows with genotype CC is 3.14 times higher than for the heterozygous animals. Apart from LEP-R25C, also FF homozygotes at the LEP-Y7F substitution attribute 3.64 times higher risk of culling than the YY homozygotes and VV homozygotes at LEP-A80V have 1.83 times higher risk of culling than AA homozygotes. Differences in risks between genotypes of polymorphisms within the other genes (the butyrophilin subfamily 1 member A1 gene, BTN1A1; the acyl-CoA:diacylglycerol acyltransferase 1 gene, DGAT1; the leptin receptor gene, LEPR; the ATP-binding cassette sub-family G member 2, ABCG2) are much smaller.ConclusionsOur results indicate association between LEP and longevity and are very well supported by results of other studies related to dairy cattle. In view of the growing importance of functional traits in dairy cattle, LEP polymorphisms should be considered as markers supporting selection decisions. Furthermore, since the relationship between both LEP polymorphism and its protein product with longevity in humans is well documented, with our result we were able to demonstrate that livestock with its detailed records of family structure, genetic, and environmental factors as well as extensive trait recording can be a good model organism for research aspects related to humans.

ABSTRACT:Genetic parameters for somatic cell score in the first three lactations of Polish Holstein-Friesian cattle were estimated. A multiple-lactation model was applied with random herd-test-day effect, fixed regressions for herd-year and age-season of calving, and random regressions for the additive genetic and permanent environmental effects. The large data set was used that included over one million test-day records and more than 58 000 cows. Estimates of covariance components and genetic parameters were obtained by Bayesian methods using the Gibbs sampler. Average daily heritabilities of somatic cell score (SCS) in the first three lactations were 0.11, 0.12 and 0.14 for the first, second and third lactation, respectively. Estimates of daily heritabilities were rather independent of days in milk (DIM), with no serious abnormalities at the beginning or the end of lactation. Average genetic correlations between SCS on the same DIM were 0.68, 0.62 and 0.70 for first and second, first and third, and second and third parities, respectively, and did not exceed 0.77. The low level of heritability estimates and relatively low genetic correlations between lactations would suggest that selection based on the first lactation only could limit a response in mastitis resistance for later lactations.