Selection of live animals with minimum carcass fat in animal breeding programs will lead to increase inmeat production at national level. The ligands of Wnt genes are of the effective factors in adipocyte celldifferentiation. This study was aimed to assess the association between polymorphisms in Wnt10a andWnt10b genes and carcass traits in 96 Afshari – Booroola Merino male lambs. In this study, DNA wasextracted from blood samples using phenol-chloroform extraction method and polymerase chain reactionwas performed for amplification a 663 bp fragment of exon III and a part of the second intron of Wnt10agene and a 512 bp fragment of exon III Wnt10b gene. The results showed a polymorphism and threemonomorphisms (a different allele compared to reference sequence of the gene) in the Wnt10a gene butall the sequences of the Wnt10b fragment were the same in studied region of the gene. Results of thesequencing lead to identification of four single nucleotide changes in Wnt10a gene in the studied areawhen compared to the reference sequence. One of the monomorphisms was in the intron and among otherthree nucleotide changes identified in exon III one was a missense in codon 139. After digestion withrestriction enzymes HpaII at this codon, it was observed that all sampled lambs had mutant homozygousgenotype compared to the reference sequence. This site was also evaluated in a number of Afshari (fattailed)and Zell (with the least fat tail) but again the same results were observed. Therefore, it seems thatin this position the G is the wild type allele in the studied population.

Introduction: One of the most important sources of the red meat in Iran is the meat produced from sheep. Increasing lamb per ewe considered as a strategy for improving the efficiency for sheep production, although reproduction traits have low heritability. Several genes associated with reproduction were investigated in the recent years. The BMP 15 gene and its paralog GDF 9 and receptor, BMPR-IB, are related to fecundity in sheep and attracted the interest of breeders recently. All these genes that are members of TGFb super family are functionally closely related together and they affect expression and secretion of hormones affecting follicle growth and ovulation rate in mammals. BMP15 plays a key role in regulating many processes in granulosa cells and ovulation rate. Mutations in some candidate genes such as BMP 15 proved to affect the lambing rate. Since 2008, introgression of the BMP Receptor IB mutant (FecB) from Booroola Merino (from New Zealand) into Afshari sheep was initiated. Thereafter, several genes that proved to have an effect on reproductive traits were studied in this breed. This study was conducted to identify possible polymorphism(s) in BMP 15 and to compare its expression in ovaries of pregnant and non-pregnant ewes.Materials and Methods: To study these, blood samples were collected from 35 and 45 Afshari and Afshari × Booroola Merino ewes, respectively. DNA was extracted from all samples using phenol-chloroform procedure and Total RNA was extracted using the RNA extraction kit, CinnaPure RNA Kit (Cinnagen Inc®, Iran), extraction was performed according to the manufacturer’s instruction. To remove any possible residual DNA contamination, RNA samples were treated with 1 unit of DNase (Vivantis Inc®, Malaysia). The specific primers were designed for three areas of BMP 15, namely promotor (581 bp), exon one (325 bp) and exon two (857 bp) and the targets were amplified using PCR. The PCR products were sequenced using forward and reverse primer for all of the samples.Result and discussion: There was no difference among sequences of the promoter and the first exon among samples. But, a nucleotide in position 134 of the second exon, C was replaced by A, was observed in two samples with heterozygote genotypes AC instead of CC. Nonetheless, the codon of amino acid encoding proline is remained unchanged. This mutation occurred in two Afshari × Booroola Merino ewes. This mutation, to our knowledge, was not reported to date. Parents of these ewes were not available and also due to the low frequency of the mutation, detection and identification breed of the origin for the mutation was not possible. To date, such a mutation neither was reported in Afshari nor in Booroola Merino breeds. Obviously, the promoter of the gene is conserved and it shows high similarity amongst related species. Nevertheless, in our study sample size was limited to conclude this well. Considering conservation of the promoter of the gene within the species and closely related species, it appears that the regulatory regions were very protected and required for its sustained action. Given that a number of animals used in the study were twine bearing Afshari × Booroola Merino crosses, but there was no difference between them and Afshari pure breed in terms of BMP15 gene expression and gene sequences. Thereupon, the results of this study indicate that this gene plays no role in litter size of this new genetic component. In order to assess the expression of this gene in ovaries of the ewes, after slaughtering, ovary samples of 22 pregnant ewes and those of 8 none pregnant were collected. Total RNA was extracted from the samples and mRNA converted to cDNA using oligo d (T) primer and reverse transcriptase. Glyceraldehyde 3- phosphate dehydrogenase (GAPDH) was used as the endogenous control for normalization. Results of real time PCR using designed specific primers showed no difference in BMP 15 gene expression between pregnant and non-pregnant ewes.Conclusion: It is possible that this gene plays its role in relation to other genes include their receptors and its expression is needed in different steps of reproduction. This result and reports of other studies suggest that more data on BMP15 gene with a simultaneous expression of other genes in the ovary is needed to clarify the integral role of BMP 15 in reproduction.

Domestication and selection are processes that conserve the pattern of genetic diversities between and within populations. Identification of genomic regions that are targets of selection for phenotypic traits is one of the main aims of research in animal genetics. An approach for identifying divergently selected regions of the genome is to compare FST values among loci to estimate the genetic variability between and within populations. In this study, a whole genome scan using the 50K Illumina Ovine SNP chip was performed in seventeen flocks of Australian Merino sheep (8 CRC flocks and 9 SG flocks). Population differentiation using FST in these flocks revealed seven genomic regions. These areas were located on chromosomes 2 (two region), 3, 6, 7, 16 and 26 (Wintheta>0.15). In this study, a number of candidate genes associated with reproductive and growth traits were identified. Study of the reported QTLs in these regions of the ovine and bovine genomes also showed that they associated with important traits such as reproduction, carcass yield, growth and wool traits. Further validation studies of these regions can be used to identify the candidate genes for economically important traits in sheep breeds. The results also provided intuitions for further understanding of the genetic diversities among the Merino flocks.

deciphering the genetic basis of phenotypic diversity is one of the main aims of biological research.Domestic animals are useful tool for making substantial progress towards this goal. Selection signatures are the regions of the genome that are functionally important and therefore have been under either natural or artificial selection. In this paper, a whole genome scan was performed using 3000 individuals, ~50000 SNP markers from nine populations of Australian Merino sheep, with the aim of identifying divergently selected regions of the genome. Five genomic regions on 4 chromosomes were identified as putatively harboring selective sweeps. These regions were located on chromosomes 6, 7, 11 (two areas) and 26. These selected genomic regions were surveyed to find encoding putative candidate genes and 9 genes were extracted from areas Ovine Genome v3.1 Assembly.Study of the reported QTL in these regions of the sheep genome showed that they overlapped with QTL of economically important traits such as carcass yield, growth and wool traits. Further investigation of these regions in validation studies will help to identify the candidate genes for economically important traits in sheep breeds.

Enhancement of the production and productivity in animals is possible by improving the environment and changing the genetic structure of the herd which is done through selection. The present study aimed to investigate the efficiency of using genetic resources in the population of South-Kazakh merino sheep breed to improve and enhance the quality of wool productivity by determining a combination of phenotypic traits, morphobic and chemical parameters, as well as immunogenetic factors. Wool productivity was studied and accounted for by cutting each animal's wool during the period of shearing with an accuracy of 0. 1 kg. At the age of 14 months, samples of wool were taken from 10 ewes of each group to study the yield of pure wool using physical and technological indicators. The value of reproducibility coefficients was determined by conducting correlation analysis. The value was estimated from 0. 439 to 0. 871 and 0. 331 to 0. 776 for the live weight and wool cutting, respectively. The number of woolens per 1 mm2 of skin positively correlated with pure wool cutting (0. 276±, 0. 135) and woolliness factor (0. 293±, 0. 134), while it negatively correlated with the live weight of sheep (-0. 055±, 0. 140), staple length (-0. 146±, 0. 139), and toner wool (-0. 180±, 0. 138). This negative correlation implies that the most densely woolly sheep will not necessarily have a breeding advantage for the herd improvement on a combination of signs. However, the outstanding wool density as a separate indicator of sheep woolen productivity has a great breeding advantage,therefore, in the merino population, it is necessary to create a small factory line of sheep with a very large wool density. A variety of sheep productivity indices in each age had a high correlation with a variety of maximum productivity levels of animals bred in the conditions of "Batay-Shu" LLP.

Accurate estimation of variance components using pedigree and genomic data plays a key role in prediction of breeding values. Since SNP markers in genomic selection are distributed across the genome, they may cover all quantitative traits loci and potentially explain all of genetic variation. In this study, genotype data from Merino sheep, genotyped by 50k Illumina SNP chip were used. Staple length and Fibre diameter traits were studied in this research. To study the association between allele frequency spectrum and captured additive genetic variance, all SNPs were partitioned in five MAF bins with the equal numbers of SNPs. Two statistical models including separate analysis for each category of MAF SNPs or joint analysis of all MAF groups were fitted. The analysis were performed using REML (parametric) and a Bayesian method implemented via Gibbs sampling and RKHS (semi-parametric) model. Using all common SNPs in REML approach, estimates of genomic heritability were 0. 72 and 0. 48 for Staple length and Fibre diameter, respectively. In Bayesian approach, genomic heritability for mentioned traits were 0. 74 and 0. 47 respectively. In the separate analysis, estimates of genomic heritability using REML and Bayesian approaches for each MAF class were similar, but in joint analysis estimates of two approaches were different. Overall, when the model is simple both approaches perform similarly while when model is complicated as joint analysis in present study, two approaches work different. Therefore, to determine which approach is more reliable, further research is required

Growth hormone is one of the main factors affecting the growth of animals. Dِِifferent alleles of this gene, may lead to different phenotypic effects. The aim of this study was to identify alleles of this gene in exon 5 and part of the 3′ downstream area. For this purpose, 133 lambs from a flock and ultimately at the same age in three groups of Afshari pure breed and F2 and F5 crosses of Afshari-Booroola Merino were used. After taking Blood samples and recording the phenotypic measurements on live animals, 85 lambs were slaughtered. Afterward, carcass weight was measured. After 24 hours storing the carcasses in the cold room the weight of thigh, shoulder, neck, fat tail right side of carcass and waste was measured. Regression coefficient analyses were used to estimate carcass traits of those animals that were not slaughtered. DNA was extracted by phenol-chloroform procedures from blood samples. Then, using designed primers, the desired fragment was amplified and directly sequenced. Afterward, by analyzing of sequences, association of genotypes with carcass traits were evaluated. The results showed that in the nucleotide site of 2846 there were two genotypes, TT and TC, affecting the length of the body in Afshari pure breed and F5 crosses. In position 2882 sequence of the gene, a nucleotide was inserted in some animals and this insertion only in F2 crosses was associated with waste (carcass fat). Our results on the observed variations in case be proved by further evaluations, it can be used in marker assisted selection program in sheep breeding.