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In this study 8 genes of growth factors and their receptors were investigated that are known to play a significant role in signaling pathways involved in the ontogenetic, but also tumorigenic, development of breast and mammary glands. Differential expression of fibroblast growth factor receptor 2 (FGFR2), GH receptor (GHR), hepatocyte growth factor (HGF), hepatocyte growth factor receptor (HGFR), plateletderived growth factor [alpha] (PDGFA), platelet-derived growth factor receptor [alpha] (PDGFRA), platelet-derived growth factor [beta] (PDGFB), and vascular endothelial growth factor (VEGF) was analyzed in mesenchymal and epithelial teat tissue of peripubertal pigs affected and nonaffected by the inverted teat defect. Comparisons were made at the level where pigs were affected between samples derived from nonaffected animals and affected animals, including specimens of normal and inverted teats. In addition, comparisons were made at the level of the teat phenotype with normal teats of nonaffected animals vs. either the normal or the inverted teat of affected animals. All genes tested, except HGFR, showed significant differential expression at P < 0.05 in the mesenchymal or the epithelial teat tissue or both. In general, we observed more pronounced differences when comparing samples obtained from inverted tissues vs. samples from normal ones. Therefore, results of our study suggest that gene expression of the growth factors and their receptors associates directly with the teat phenotype rather than with the affection status of the investigated animals, suggesting that local processes and tissue-specific compensation by means of differential expression of growth factors and their receptors are responsible for the development of impaired teat phenotypes. Key words: expression profile, inherited disorder, inverted teat, pig, quantitative real-time polymerase chain reaction, signaling pathway doi: 10.2527/jas.2008-1660

The objective of this study was to examine the relationship of the relative abundance of transcripts of myosin heavy chain (MyHC) isoforms and muscling in several diverse pig breeds. The animals used were from 3 pure breeds (Pietrain, Duroc, and Mongcai) and 2 crosses [Duroc x Pietrain (DUPI) and Duroc x Berlin Miniature pigs (DUMI)]. Real-time PCR quantification of MyHC isoforms I, IIa, IIx, and IIb showed that the relative expression of MyHC IIb was greater in pigs with large LM areas in both DUPI (69.6 vs. 53.0%) and DUMI (60.5 vs. 47.5%). In DUPI, similar transcript levels of MyHC I were found in both large and small LM (14.7 and 15.2%), whereas in DUMI animals, these values were 18.4 and 33.5% (P < 0.05). The groups of animals with large and small LM area in the DUPI also tended to differ in MyHC IIa and IIx transcripts. The comparison among different breeds confirmed the trend of high MyHC IIb transcript abundance together with high muscularity. In Pietrain, Duroc, DUPI, and DUMI, MyHC IIb accounted for more than half of the MyHC transcripts (65.4, 59.7, 54.0, and 54.0%). Mongcai showed low MyHC IIb (11.4%) but high type I, IIa, and IIx relative RNA levels (24.1, 28.5, and 35.9%). Frequencies of fibers, determined by muscle fiber staining with ATPase, and relative abundance of MyHC isoforms, determined by quantitative reverse transcription-PCR, of corresponding pairs of type I, IIa, and IIx/ IIb were correlated (r = 0.71, 0.67, and 0.52, respectively). The study demonstrates that MyHC IIb fibers are the most prominent in pigs having large LM area and implies that MyHC IIb is the determining fiber contributing to the differentiation of large and small loin eye muscle area in the pig. Key words: longissimus dorsi, myosin heavy chain, pig, real-time polymerase chain reaction

The Romanov breed stands out from the global variety of sheep breeds. Romanovs originated from local sheep at the end of 17th century in the Volga Valley. Since the 1970s, the breed has become popular in France, Canada, and the United States. Some unique traits are of permanent interest to this Russian breed. Primarily, Romanovs have outstanding reproduction qualities: early sexual maturity, out-of-season breeding ability, and extraordinary prolificacy. Using Romanov ewes in crossbreeding programs is a profitable, practical method to increase the number of highly viable hybrids. In addition, the Romanov breed has unique wool properties, which are very suitable for manufacturing felt products, rugs, and mats. However, detailed genetic information on the breed is lacking. Therefore, we performed the whole-genome SNP analysis of the original Romanov sheep to study its genetic diversity and genetic relationships with other Russian breeds. We genotyped 42 samples of Romanovs using the OvineSNP50K BeadChip and pooled the data with the set from 24 Russian breeds. Quality filtering was performed in PLINK version 1.07. Calculations were done in PLINK version 1.07, GENETIX version 4.05, and HP-Rare 1.1. We found a lower level of genetic diversity in Romanovs (Ho = 0.350 and Ar = 1.862) in comparison with other coarse wool breeds (Ho = 0.377 and Ar = 1.899). At the same time, Romanovs, compared with the 24 breeds, were characterized by the most insignificant deviation from Hardy-Weinberg equilibrium (Fis = -0.005). In other breeds, Fis values varied from -0.028 to -0.082. Pairwise Fst values ranged from 0.084 to 0.124 between Romanovs and Kuibyshev and Kuchugur, respectively. The MDS analysis revealed the genetic uniqueness of Romanov sheep. Principal component (PC) 1 divided all breeds into 2 groups according the wool type (fine wool + semifine wool and coarse wool) with 4.7% of total genetic variance. By PC1 the Romanov formed an incorporated bunch and logically clustered with coarse-wool breeds. However, the Romanov was clearly separated from the others by PC2, which explained 3.8% of additional genetic variability. Most likely, a high level of consolidation and genetic differentiation of the Romanov breed from other Russian sheep are explained by its "pure gene" origin and was not improved by any breed. Our study is the first attempt to reveal the outstanding genetic nature of original Romanov sheep on whole-genome level. We will extend our study by genotyping more samples with medium-density DNA chip and using NGS technology. The research was performed under financial support of Russian Scientific Foundation (number 14-36-00039). [ABSTRACT FROM AUTHOR]

Monitoring of udder health status is an important element in herd management and selection success for complex fitness traits. Identification of metabolic pathways and QTL responsible for the synthesis of amino acids and fatty acids in milk allows identification of missense mutations that are also associated with high fat, protein content, and somatic cell count. The aim of our research was to evaluate genetic correlations between milk production traits and somatic cell score in relation to assessing crucial SNPs. The calculation of variance and covariance components was performed by REML. Breeding value estimates for average daily milk yield (MY), fat (FP) and protein percentage (PP), fat (FY) and protein yield (PY), somatic cell count (SCC), and somatic cell score (SCS) were based on multiple-trait mixed model using BLUPF90 family programs. The genomic relationship matrix was calculated by the GBLUP approach. GWAS analysis was carried out using Plink 1.07. The total number of genotyped Holstein bulls (Illumina Bovine SNP50) with DGV values was 466, from which 247 had 8,935 daughters' records. Genomic values were used for GWAS as pseudo phenotype data. Genetic parameters for milk production traits were calculated based on records of 845 sires with 21,540 daughters. Heritability coefficients were 0.152, 0.213, 0.204, 0.101, 0.127, 0.050, and 0.055 for MY, FP, PP, FY, PY, SCC, and SCS, respectively. Genetic correlations between SCS and MY, FP, PP were -0.059, 0.024, and 0.197, respectively. GWAS analysis performed for FP showed the strong association of SNPs localized on BTA14 while the highest value of the additive variability was observed for DGAT1 mutation (ARS-BFGL-NGS-4939, P = 1.1E×10-11, R² = 9.5%). In total, we identified 52 SNPs associated with SCS at P-values of more than 1.24 × 10-6. The coefficient of determination ranged from 5.9 to 9.2%. The greatest number of SNPs were found on BTA1, 4, 5, 8, and 17. Some of them were localized in the following key genes: rs110754403 (STXBP6, P = 2.5E×10-11), rs43072965 (KCNMB4, PTPRB, TRNACGCA, P = 2.3E×10-9), rs42600512 and rs42600489 (CNOT2, P = 3.0E×10-9), rs29019947 (117.6 to 117.9 Mb, MED12L, P2RY12, P2RY13, P2RY14, IGSF10, LOC104971001, GPR87, GPR171, P = 5.3E×10-8..7.4E×10-9), rs29020595 (CALD1, P = 1.2E×10-7). Our findings will be the basis for the development of the genomic evaluation concept for udder health and milk quality traits for the Russian Holstein and Black-and-White cattle population. Supported by the Russian Scientific Foundation, project number 15-16-00020. [ABSTRACT FROM AUTHOR]

Conservation of native cattle populations' biodiversity is a crucial element in breeding selection programs. Reduction of local and improved livestock gene pool leads to the loss of valuable alleles for adaptation to specific environments. In our work, we investigated the genetic structure of the most essential native cattle breeds in Russia. Using Illumina Bovine 50K BeadChip, we genotyped nine breeds: Bestuzhev (BEST, n = 26), Black and White (BLWT, n = 21), Kalmyk (KALM, n = 14), Kholmogor (KHLM, n = 25), Kostroma (KSTR, n = 20), Red Gorbatov (RGBT, n = 23), Suksun (SKSN, n = 20), Yakut (YAKT, n = 25), and Yaroslavl (YRSL, n = 21). Statistical analysis was performed with PLINK 1.07, Admixture 1.3 software, and R packages "diveRsity" and "adegenet." Multi-dimensional scaling (MDS) analysis showed that all of the breeds formed their own clusters. The YAKT cluster was completely separated on the first component (C1) and was most distant from all other populations. KALM also separated on C1 but was much closer to the other clusters. Both of these breeds are of Asian origin. The other seven breeds, which are of European origin, separated from one another mostly on the second component (C2). Admixture analysis showed that the most probable number of populations (K) was 8. At K = 2, YAKT was separated from the other populations. Considerable admixture of YAKT was only found in the KALM cluster (from K = 2 to K = 8). At K = 8, all of the breeds but KALM formed their own clusters. KALM was combined from the seven other breed fragments (all but SKSN). Pairwise genetic distances (FST) values were higher for YAKT (from 0.126 with KALM to 0.187 with RGBT). Fst values between the other breeds ranged from 0.036 (BLWT and SKSN) to 0.103 (KSTR and RGBT). The lowest rarified allelic richness value was observed for YAKT (1.781 ± 0.002). For all of the other breeds, it ranged from 1.919 ± 0.001 for KSTR to 1.958 ± 0.001 for KALM. Expected heterozygosity was the lowest in YAKT (0.273 ± 0.001) while in all of the other breeds it ranged from 0.329 ± 0.001 in KSTR and RGBT to 0.352 ± 0.001 in BEST. Inbreeding coefficient (FIS) values in all of the breeds were close to zero (from -0.05 to 0.01). Our study revealed that all of the evaluated Russian breeds were structured, and only KALM had a more complex admixture. The most diverged, indigenous YAKT breed had a lower genetic diversity than all of the other breeds. The study was supported by the Russian Science Foundation within Project no.14-36-00039. [ABSTRACT FROM AUTHOR]