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Background and Objectives: Identification of several genomic markers sequenced in farm animal enables us to study the structure of their genome. Samples from different parts of the world are usually used for sequencing genomic markers. Information on the sequence of specific markers of domestic animals of each geographical area will improve our knowledge about their genomic structure. The sequences of specific genome markers for Iranian native sheep have not yet been identified. Present study aims to identify single-nucleotide polymorphism (SNPs) influencing important economic and physiological traits of Iranian domestic and wild sheep as candidate markers using selection signature. Materials and Methods: In order to identify significant genetic variants under selection in domestic and wild sheep, the whole genome sequence of 20 domestic (Ovis aries) and 14 wild sheep (Ovis orientalis) obtained from the Next Gene project were used. After doing quality control, variant under selection were detected using statistical methods consisting iHS and XP-EHH. Genetic variances for identified variants were estimated. The genetic variance of known variants in Merino, Suffolk, Texel and Afshari were also estimated. The threshold for selecting variants based on iHS and XP-EHH methods were considered to be 99.9% in domestic sheep and 99.9% and 0.001% in wild sheep, respectively. Finally, variants with genetic variances higher than 0.25, were identified and suggested as candidate markers. Results: In the present study, 170 genomic variants with iHS and XP-EHH values higher than 3.83 and 3.44 in domestic sheep, and 150 genomic variants with iHS values higher than 3.05, and XP-EHH values lower than -4.43 in wild sheep were identified and suggested as candidate markers. Genetic variances of these variants were 0.27 to 0.50 and the genetic variance of known variants in Merino, Suffolk, Texel and Afshari were from 0.02 to 0.50. This comparison shows the importance of identified variants in Iranian domestic and wild sheep. Most of identified variants in domestic and wild sheep, associated with economically important traits including carcass, milk, and wool associated traits. The ontology of genes related to identified variants showed that these variants are located near genes related to metabolic process of production and reproduction traits Conclusion: Present results showed that there are many significant genetic variants associated with economic traits in domestic and wild Iranian sheep which are not included in the commercial sheep arrays available in the market. Identification of new SNPs related to economic traits in domestic and wild sheep may help to improve the studies related to genomic structure of Iranian sheep. These results together with similar studies could be efficiently used for producing SNP arrays designed for Iranian native sheep. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare two strategies in Mazandaran native fowls using computer simulation. Simulated traits included body weight at birth (BW1), at eight weeks of age (BW8), at twelve weeks of age (BW12), at maturation (BWM), age at sexual maturity (AFE), weight of first egg (EWM), mean egg weight from 28 to 32 weeks of age (EW28-32) and egg number (EN). The first strategy was to select cockerels based on breeding value of BW12 and hens based on a selection index with 4-traits including BW12, AFE, EW28-32 and EN. The second strategy was to select cockerels and hens using a selection index based on a 4-traits including BW12, AFE, EW28-32 and EN. After 10 generations, the first strategy improved BW1, BW12, BWM, EW28-32 and EWM to 1.49, 573.81, 397.58, 3.96, and 3.75 grams and AFE and EN to -3.51 days and 2.09 eggs, respectively. After 10 generations, the gain for traits in the second strategy for BW12, BWM, AFE and EN was 415.78, 218.74 grams and -9.77 days and 9.45 eggs, respectively. At the end of the tenth generation increase of inbreeding in the first and second strategies was 0.048 and 0.070, respectively. The results showed that the first strategy was suitable for a breeder flocks with the aim of chickens suitable for broiler production and the second strategy was suitable for a dual-purpose flocks with the aim of producing egg and meat. [ABSTRACT FROM AUTHOR]

The present study was carried out to determine population structure of Alosa braschnikowi, one of the endemic species in the Caspian Sea, with five polymorphic microsatellite loci (AsaD030, AsaD042, AsaC249, AsaD312, AsaC051). Fifty six specimens of A. braschnikowi were collected from Gomishan and Miankaleh (28 specimens for each population) in Golestan province. The results showed that the average observed heterozygosity for Gomishan and Miankaleh were 0.536 and 0.514, respectively, with an average of 0.525 for the two populations. The number of observed alleles per locus ranged from 8 to 17 with an average of 12.4 alleles. Average number of effective allele in Gomishan and Miankaleh was calculated 8.53 and 7.61. Also, in eight cases of 10 tests in Hardy-Weinberg equilibrium there was statistically significant deviation (P<0.001). The average amount of gene flow and Fis were 17.34 and 0.395, respectively. The Fst value was 0.016 which was indicative of the low genetic differentiation between the Gomishan and Miankaleh populations that could be due to the natural migration of the fishs. The results for molecular variance analysis based on Fst index, exhibited that genetic diversity within population was only 1 percent and among populations was 99 percent. The results of present study showed that although the genetic diversity of A. braschnikowi in Golestan province was appropriate, it is possible that genetic bottleneck will arise in future years. [ABSTRACT FROM AUTHOR]