sheep

This research aimed to assess the effect of feeding Salicornia bigelovii fodder on the growth and carcass performance of fattening lambs. The experiment was conducted using 63 male Afshari lambs in a completely randomized design with seven treatments and nine replications for 100 days. The treatments were diet without Salicornia (control) and diets containing levels of 45, 90, 135, 180, 225, and 270 g Salicornia, instead of alfalfa/kg DM. Compared to alfalfa, Salicornia contained lower amounts of protein, nitrate, and neutral detergent fiber (NDF), but higher content of ash, sodium, oxalate, and phenolic compounds. Feeding increasing levels of Salicornia caused a linear increase in daily water consumption (P<0.05). Daily intake of DM increased with increasing Salicornia levels (P=0.05), but consumption of organic matter (OM) and crude protein did not differ. Salicornia feeding had no significant effect on daily growth and feed conversion based on diet OM, but at levels of 135 g and more, it caused a decrease in feed conversion based on diet DM. Digestibility of DM (P=0.072) and ash (P=0.012) increased and NDF digestibility decreased (P=0.048) with increasing Salicornia consumption, but the digestibility of OM, crude protein and ether extract, and carcass yield did not change. Overall, feeding Salicornia up to 270 g/kg diet DM (with a forage-to-concentrate ratio of 40:60) increased the water consumption of animals, but it did not have a negative effect on the performance of fattening lambs, and it can be recommended to replace a portion of the diet forage in male Afshari sheep.

Currently, sheep breeding in Iran aims to produce meat; therefore increasing production in this part requires measures such as breeding and short-term solutions such as improving health and nutritional conditions. Understanding the growth and development of skeletal muscle is one of the most important goals in the animal breeding and meat production industry, which can be related to special aspects of human medicine. Therefore, the aim of this research was to determine the effect of glutamine feeding as a nutritional strategy on myogenic gene expression in the muscle of Zell sheep under heat stress conditions.

Zell sheep cows (n = 12) with an average weight of 25.0±1 Kg randomly assigned fed with different glutamine levels (0 and 0.2 g/kg body weight. Diets were fed for 60 days under heat stress conditions. Sampling of the thigh muscle was taken at two different times (in the middle of the experiment and at the end of the experimental period) with a special biopsy gun with a 14-diameter needle from three sheep in each treatment. Then the samples were washed in physiological serum and kept at -96°C until total RNA extraction. RNA extraction was done with trizol and based on manufacture instructions (Invitrogen). The RNA was reversely transcribed in the presence of 1 mmol/L oligo (dT) primer and 4 U Omniscript RTase (Omniscript RT Kit; Qiagen, Mississauga, Ontario, Canada) according to the manufacturer’s instructions. To ensure the amplification, they were tested using a cDNA and Real-time PCR (model CORBETT 3000, Australia). Data were normalized to a calibrator sample using the 2ΔΔCt method with correction for amplification efficiency. Samples were expressed relative to YWHAZ as a housekeeping gene, which was stable under the culture conditions used. Data was analyzed using t-test (SAS 9/1).

The results of the present study showed that glutamine feeding increased the expression of Myf5 (2.75 times), MyoD (3.89 times), MRF4 (2.16 times), Myogenin (4.76 times), and the expression of Myostatin gene (54 4 times) on the 21st day of the experiment. On the 42nd day of the experiment, glutamine feeding increased the expression of Myf5 (2.10 times), MyoD (2.56 times), MRF4 (2.78 times), and Myogenin (5.25 times) genes, like the 21st day of glutamine feeding. And it decreased the expression of the Myostatin gene (3.03 times) on the contrary.

The results of the present study showed, in general, that considering the effect of glutamine nutrition on the expression of myogenic genes in heat conditions, its use can be a solution to increase growth performance in heat stress conditions if the results are reproducible.Keywords: Gene expression, Glutamine, Sheep, Real-time- PCR

To date, one of the main areas of research is the creation of breeds with inherent resistance to digestive nematodes in sheep. In this context, resistance to digestive nematodes has exhibited significant phenotypic differences within and between sheep breeds, suggesting a genetic basis for these differences. According to the list of effective candidate genes and the identified gene network for parasite resistance in sheep, there are genes involved in the immune system, such as the interferon-γ gene (IFN-γ). Cytokinin is involved in biochemical immune system signaling pathways, parasite resistance, and immunological responses. In addition, certain mutations in this gene impair the ability of specialized cells of the immune system to fight off parasite invasion. One of the most popular approaches to generating gene expression data for genome function studies is DNA microarray technology, which allows the simultaneous expression of thousands of genes. Proteomics and genomics are two application areas of microarray technology. This research aims to identify and categorize some of the genes involved in the relative genetic resistance of sheep to nematode infection using microarray data.

In this context, the GEO-Bank, part of the NCBI, was searched for access to open-access databases. Downloaded microarray data corresponded to infection with parasitic nematodes with the best replication (e.g., data in two resistant and sensitive groups), and the set of genes with differential expression was identified using R -based appropriate software packages (Biobase, GEOquery, limma, affy, Genfilter, Pheatmap, Plyr, Reshape2, and Ggplot2). Raw data were measured on a logarithmic scale, and the P-value fit statistics were used for expression comparisons between gene groups.

The main analysis was performed after precorrection and processing of the raw data because of the high intragroup variance of the data, as evidenced by the observed quality control results of the raw data and the quality control-related results of the integrated data. After pre-processing of the raw data, correlation analysis revealed a strong relationship between genes in the pre-Inf group (Pre-Inf) and the infected group (Inf) compared to the control group. Three heatmap reference charts, a PCA chart, and a volcano plot were used to verify data quality, and by verifying these charts, samples of unfavorable quality were removed from the next stages of analysis. After a bioinformatics analysis, the results showed significantly increased expression patterns (NACA, RPL4, NAGS, CTCF, GBP1, BHLHE, YTHDF3, PDHA1, and MXI1) and diminished expression patterns of PDHA1 and MXI1 genes. According to the results of this study, these genes play a role in the cellular metabolism process, molecular function, the formation of genetic connections, and cell life. Therefore, they were significant (p-value < 0.05) according to the magnitude of the change. The N-acryl glutamate synthetase (NAGS) gene is the cofactor of the first enzyme involved in the urea cycle in mammals. The functional role of this gene has been identified in many neurological diseases. The CTCF gene has a positive effect on the cells of the immune system and plays a special role in defending against viruses and pathogens that invade the host body. The guanylate binding protein 1 (GBP1) gene plays a role in the body's defense against many infectious pathogens. This gene causes oxidative reactions and autophagy of the host immune system as a barrier to invading pathogens. The methyl adenosine RNA binding 3 gene is more effective in antiviral immunity and is closely linked to the GBP1 gene, which plays a role in the body's resistance to many infectious agents. This gene causes oxidative responses and autophagy of the host immune system against invading pathogens. The PDHA1 pyruvate dehydrogenase gene is involved in immune system metabolism. This gene plays a role in allosteric factor-induced regulation, repair of covalent bonds, and relatively rapid changes in the level of expressed proteins, either through altered gene expression or proteolytic degradation. The MXI1 gene helps control the entry of invading pathogens into the host's body and promotes recovery and healing from infections. The results can be explained by several reasons, including the use of different sample breeds and laboratory techniques, the level of parasite contamination, the age of the test material, the variety of tested nematodes, and inconsistent techniques and tools of the current study with those of previous studies. Other reasons include the climatic differences between the test region and its physical location as well as the use of different RNA and microarray methods. However, the results of the study may be helpful under the related circumstances.

The results of microarrays and differential expression patterns can be of great help to molecularly modify livestock to resist internal parasites. Using more advanced tools, such as next-gene sequencing, will provide more accurate and relevant information.

Iodine is a structural component of thyroid hormones (T3 and T4), which are essential for the life of mammals. Iodine deficiency leads to insufficient production of thyroid hormones, which is primarily due to the lack of iodine in the soil. Selenium is also involved in the metabolism of thyroid hormones by participating in the construction of selenoproteins that convert the inactive form of T4 into the active form of T3. The aim of this study was to investigate the effects of iodine supplementation on thyroid hormone concentrations of in ewes exposed to iodine deficiency under selenium deficient or sufficient conditions.

A flock of sheep was selected in an area where selenium and iodine deficiency had been identified. In this flock, 30 young ewes (2-3 births) of Farahani breed with similar body weight (47 ± 6 kg) were randomly divided into three groups, including a control group and two experimental groups. The first and second experimental groups received 390 mg of iodine in the form of fatty acid ethyl ester from safflower oil at the end of gestation at the end of winter season, and the second experimental group received 10 ml of selenium supplement in the form of subcutaneous injection. The concentration of thyroid hormones, including triiodothyronine and thyroxine, inorganic iodine in serum and selenium concentration in blood serum were measured and compared before the beginning of the experiment and monthly until the third month in the experimental groups.

The inorganic iodine concentration in the serum of the experimental animals at the beginning of the experiment was 15.53 μg /L and the selenium concentration in the blood serum was 79.73 ng/ml, both of which were in the deficiency range. Iodine supplementation caused a significant increase in the concentration of inorganic iodine in blood serum in the experimental groups compared to the control group in all three months of sampling (P < 0.01). Selenium supplementation also caused a significant increase in blood serum selenium concentration in the selenium+ iodine-supplemented group compared with baseline and the control and iodine supplemented groups in all months of the experiment (P < 0.01). In the first experimental month after iodine supplementation, an increase in T4 hormone concentration was observed in the iodine-supplemented group and in the iodine + selenium supplemented group compared with baseline and the control group. The concentration of T4 hormone was higher in the iodine supplementation group than in the control group and in the iodine + selenium supplementation group in the second and third months. Iodine supplementation increased T3 concentration in the first and second months of the trial compared with baseline, and selenium supplementation also significantly increased T3 concentration in the first and second months of the trial in the iodine + selenium supplemented group compared with the iodine supplemented group and the control group. The increase in the concentration of thyroid hormones after iodine supplementation showed that the production of these hormones was affected by iodine deficiency. Selenium supplementation increased the concentration of T3 in the first and second months and decreased the ratio of T4 to T3 in the second month. It showed that the effect of iodine supplementation is better in the conditions of selenium sufficiency.

The results indicate the effect of iodine supplementation to increase inorganic iodine concentration in serum, and the increase in thyroid hormone concentration after iodine supplementation indicates the limiting effect of iodine deficiency on the production of these hormones under iodine deficiency conditions. In selenium deficiency, the effect of iodine supplementation on T3 hormone production may be limited.

Animal husbandry as an economic sub-sector is one of the most successful productive activities of the agricultural sector, which plays a very effective role in providing food for society. On the other hand, the economic growth of society, the increase in household consumption of livestock products and the population growth have caused an increase in demand for these products. The transition from traditional to modern agriculture and the distance of the centers of consumption from the production areas, mostly located in marginal and rural areas, has led to an importance of the marketing of agricultural products. Marketing methods of agricultural and animal products in Iran are expensive and incompatible with the goals of sustainable development of the rural economy. Therefore, there are many problems such as price volatility, high production costs, the presence of merchants, as well as the insufficient government support about market development and marketing policy for rural products, also in relation to the marketing of agricultural and animal products in Ahar County. Therefore, this research attempts to analyze the factors affecting marketing of sheep in Ahar County using the generalized Poisson regression method.

The purpose of this study is analysis of factors affecting marketing of sheep in Ahar County using the generalized Poisson regression method. In this study, the dependent variable is numerical. Linear regression methods cannot be used in studies where the dependent variable is countable because the dependent variable in these models must follow a normal distribution and be continuous. Therefore, using the Poisson regression model is considered to be a suitable method for conducting investigations where the dependent variable is numerical in nature. To achieve the research goal, the normal Poisson regression was first estimated, but due to the fact that the mean and variance of the dependent variables were not equal, the surrogate model, that is, the generalized Poisson regression, was also estimated. Next, the Akaike and Schwartz-Bayesian information criteria were used to ensure the adequacy of the generalized Poisson model. Considering that the amount of the Akaike and Schwartz-Bayes statistic was smaller in the generalized Poisson model, the generalized Poisson model was considered to be an appropriate model. Data were collected by completing a questionnaire from 100 Ahar County ranchers using a simple random sampling procedure. Stata15 software was used to estimate the models.

Because the mean (52.84) and variance (2576.70) of the dependent variable are not equal, the normal Poisson model is not appropriate and the generalized Poisson model must be used. Also, Akaike’s statistic (AIC) and Schwartz-Bayesian (BIC) in the Poisson model are 1132/912 and 1161/569, respectively, while in the generalized Poisson model they are 838/432 and 869/694. Therefore, the generalized Poisson model is better than the Poisson model. The coefficients of all variables in the generalized Poisson model are significant. Since Poisson regression coefficients are difficult to interpret directly, their incidence risk ratio (IRR) values were calculated. The results of the incidence risk ratio estimation indicate that living in the city (0.674) and distance to the nearest sheep market (0.988) had a negative effect and having a suitable corral (2.004), attitude of breeders to improve breeds (1.373), having of farm income (1.329), access to credits (1.217), prepare animal feed in time (1.212), access to veterinary services (1.212), access to suitable pastures (1.210) and number of sheep (1.003) had a positive effect on the number of sheep marketed.

The results showed that several factors are involved in the amount of sheep sales in the study area. One of these factors is the attitude of the region's breeders to the improved and high-yielding breeds of sheep and, accordingly, their willingness to buy and breed these sheep. Because improved sheep increase the market power of the ranchers through their characteristics such as twins and the production of higher products. Another factor that is effective in rancher marketing is the distance between the rancher and the sheep market. The rancher thinks a longer distance as higher marketing costs, resulting in a decrease in sales. Ranchers who live in the city and whose primary residence is far from where their sheep are raised cannot take good care of their sheep, resulting in a drop in production and ultimately a drop in the productivity of the individual in the thing leads of marketing. Based on the results, farmers who have more sheep can sell more. Farmers who have other economic activities besides animal husbandry can use the income from these activities to expand and improve sheep farming and increase the number of sales and their income levels. Access to pastures and credit will lead to higher income levels. Having a suitable corral for keeping livestock has the greatest impact on the number of sheep sold. It is obvious that if the rancher does not have a suitable place to keep the livestock, he will not be able to continue his activity. The results indicated that appropriate measures to facilitate access to credit may be through finance the construction of suitable corral, provide cattle feed and increase the number of flocks, can be an effective measure to increase the number of sheep offered on the market. In addition, improving veterinary care and conducting educational and extension courses to eliminate negative attitudes towards improved sheep are considered effective management measures.

Sheep are the main source of wool and its fiber characteristics, such as diameter, length, and color, which are determined by genetics and environmental factors, are key features in the economic value of sheep wool. In sheep, white wool has the highest economic value due to its dyeability, thus, the identification of mechanisms responsible for coating color determination is very important from an economic point of view. In general, the coat color is determined based on the amounts and types of melanin produced and released by the melanocytes in the skin tissue (Ito et al., 2000). The genetic basis and genes involved in coat color are well understood in rodents, although many of these genes are incorporated in coat color regulation in other species; including Sheep also have a common role. In Iran, the Lori Bakhtiari sheep is one of the most important breeds of sheep in terms of the use of its wool in the textile and carpet industries. In his breed, the dominant coat of the wool is white, although sometimes a percentage of dark brown and pale brown is also observed (Saadat Nouri, M. & Siah Mansour, 1368). However, in this breed, some animals have black spots on their coat, which leads to a decrease in wool quality. Since MC1R, ASIP, KLF4 and MITF genes play an important role in controlling and determining coat color in mammals, the purpose of this study was to investigate the expression of these genes in two phenotypes of white and black spots in the skin tissue of Lori Bakhtiari sheep. Skin samples were obtained from both white and dark parts of 14 white-coated sheep with black spots and total RNA was extracted. The quality and quantity of extracted RNAs were evaluated by agarose gel electrophoresis and spectrophotometer. Extracted RNA samples were exposed to DNase1 enzyme digestion to remove the possible contamination of genomic DNA. Also, the quality of synthesized cDNA was evaluated using 1% agarose gel. In this research, in order to amplify a fragment of the studied genes, using the mRNA sequence of these genes in the GenBank database, appropriate primers were designed by Primer3plus software. To evaluate the relative expression of the target genes, β-actin and GAPDH genes were used as reference genes to normalize the data. Finally, BestKeeper and REST 2009 V2.0.13 software were used for the analysis of gene expression data. Based on the descriptive results of Ct values, MC1R and MITF genes revealed minimum and maximum expression stability among the target genes in skin samples with standard deviations of 1.34 and 3.62, respectively. In addition, the reference genes (β-actin and GAPDH) showed the highest stability among all the studied genes. No significant differences were observed in mRNA levels of MC1R, ASIP, KLF4, and MITF genes in the spotted skin tissue compared to the white part of the skin (p>0.05). However, the expression of the ASIP gene was more than 2 times in the spotted part compared to the white skin, but this difference was not significant (p=0.21). In addition, the MC1R gene showed minimum expression differences in black spots and white parts of the skin tissue. In addition, the MITF and MC1R genes showed the highest and lowest levels of expression in skin samples of Lori Bakhtiari breed sheep with average Ct of 25.86 and 30.42, respectively. However, among all the studied genes, the lowest mRNA level was observed for the GAPDH gene with an average Ct of 35.96. Mammalian coat color results from various factors such as the degree and distribution of melanin pigment and the interaction between genotype and environment (B. Li et al., 2018). In addition, melanogenesis is a complex process that includes melanocyte growth, melanosome formation, melanin synthesis, melanin transport, and melanosome release (Ito & Wakamatsu, 2011). According to the conducted studies, a large number of genes are involved in the mechanism of coat color determination, but two genes, MC1R and ASIP, play an essential role in the regulation and control of coat color (Searle, 1968). In our study, no significant difference was observed in the expression of MC1R, ASIP, KFL4, and MITF genes in the spotted compared to the white part of the skin tissue in Lori Bakhtiari sheep. These results showed that the development of skin spots is not under the control of the studied genes in Lori Bakhtiari sheep, and genes or other factors can play roles in the creation of dark spots in this breed.

Pedigree and weight trait records belonging to 13633 Baluchi lambs descendent from 308 ram and 3747 dam which were collected in North-east animal breeding center from years 1989 to 2021 were used. Six univariate animal models with fixed (birth year, month, type, sex of lamb and age of dam) and different random effects were fitted to data. Effects of non-genetic factors on weight traits were investigated by Proc GLM of SAS software, and to estimate the variance components the Wombat software was used. All fixed effects had significant effect on the studied traits (P<0.001). Model with additive autosomal, sex linked, and additive maternal random with covariance between direct additive genetic and maternal genetic effect had the lowest AIC and was used for genetic analysis. For birth, weaning, 6, 9 month and yearling weight respectively additive autosomal heritability were 0.16, 0.34, 0.41, 0.49 and 0.56, additive sex-linked heritability were 0.004, 0, 0, 0.007 and 0.005 and maternal heritability were 0.34, 0.38, 0.32, 0.32 and 0.36. Results showed that sex-linked genes possibly have negligible and close to zero additive genetic effects on body weights at initial ages and in comparison, more noticeable effects on body weights at higher ages. In general, it is recommended to use an animal model for genetic analysis of growth traits in sheep, which is able to separate the total genetic variance into three autosomal, sex-dependent and maternal components in order to be more effective in genetic selection.

associated with milk related traits and somatic cell scores through genome-wide association study based on gene-set enrichment analysis in Valle del Belice sheep breed. To this end, the genotypic information of 476 sheep of this breed along with phenotypic records related to production traits including milk yield and milk composition were evaluated using PLINK v. 1.9. After performing various quality control steps, finally 42285 SNP markers in 426 animals were used for follow-up analysis. The results of the genome wide association study (GWAS) showed that 1830, 1577, 2186, 793, 710 and 1063 SNP markers are associated with milk yield, amount and percentage of fat, amount and percentage of protein and somatic cell score in Valle del Belice sheep, respectively (P-value ≤ 0.05). The results of the analysis based on gene-set enrichment led to the identification of pathways (candidate genes) of lipid phosphorylation (including TTC7B candidate gene), lipoprotein transport (ZDHHC17 gene), regulation of calcium ion transport (ATP2B2 gene) and pathway of peptide hormone processing (PCSK6 gene) associated with milk yield; regulation of fatty acid metabolic process (IRS1 and SLC45A3 genes) related to milk fat; the signal transduction by protein phosphorylation (ERCC6 gene) and the pathway of sulfur amino acid metabolic process (NOX4 gene) in relationship with milk protein; and finally the pathways of positive regulation of response to biotic stimulus (PRKCA gene), response pathway to external stimuli (CACNA2D1 gene), regulation of response to stress (EGFR and HSP90B1 genes) and response to bacterium (candidate gene ANXA3) related to somatic cell score.

In this study in order to estimate inbreeding coefficient and identify the ROH Islands associated with the genes under selection, the 50k BeadChip genotyped data of 206 sheep from 3 different Egyptian breeds were used. After quality control, 48361 SNPs in 204 sheep were remained for the future analysis. Inbreeding coefficient was calculated using four methods including, genomic relationship matrix (FGRM), excess of homozygosity (FHOM), correlation between uniting gametes (FUNI) using the GCTA 1.0 software and run of homozygosity (FROH) using the PLINK 1.9 software. One percent of SNP with the highest frequency in ROH were considered as ROH Islands. The lowest rate of inbreeding according to (FGRM, FHOM, and FUNI) was related to Wahati and the highest was related to Saidi breed. The highest amount of FROH (0.043) was observed in Saidi and the lowest amount (0.018) was observed in Barki breed. Average length of ROH ranged from 45.02 to 205.87 Mb, while the average number of ROH ranged from 8.14 to 14.07. The highest number ROH was observed on chromosome 2, while the lowest was on chromosome 26. Average inbreeding coefficient from FROH in Barki, Saidi and Wahati were estimated 0.018, 0.043 and 0.027 respectively. A total of 62 ROH Islands with length: 24.60 Kb to 13 Mb were identified, which covering less than 1% of the sheep genome. The ROH Islands was not distributed across the genome uniform and varied among breeds, but some common were identified. Bioinformatics analysis demonstrated that some of these genomic regions overlapped with reported genes that directly or indirectly influenced traits for adaptation and immune system (SEMA3D, CSF2, ITPR1), development of the skeletal muscle (UGGT1, ITGA2), and reproduction (ABHD16B). The results of this study revealed that, the selection processes in different sheep breeds for economic traits during several years, has led to the formation of many ROH islands in sheep genome, therefore scanning these regions at the genome level can be an alternative strategy to identify genes and associated loci with economic traits.

Sheep are used as a genetic model to study the relationship between genetic diversity and ovulation rate. Previous studies have shown that ovulation rate and litter size can be controlled by a set of genes called fecundity genes . Three fertility genes have been identified in sheep called BMPR1B or FecB, GDF9 or FecG and BMP15 or FecX. Tetra-ARMS-PCR is a suitable alternative method in the context of expensive methods such as sequencing and PCR-RFLP to identify SNPs whose sequences are known. The entry of the Booroola allele into the Afshari breed increased the frequency of litter size. The aim of this study was to investigate the polymorphism of two fertility genes including FecB and FecG in Mughani, Afshari and Baluchi sheep in Khorasan Razavi province.Blood samples were taken from 95 Afshari, Baluchi and Mughani sheep. Two pairs of control (outer) and specific (inner) primers were used to amplify FecB and FecG gene fragments by the Tetra-ARMS PCR method. Temperature cycling of PCR amplification for FecB started at 94°C for 4 minutes, followed by 35 cycles consisting of 94°C for 25 seconds, annealing temperature at 54°C for 35 seconds, extension at 72°C for 20 seconds and a final extension at 72°C for 5 minutes. For amplification of the G1 point mutation on the FecG gene, the annealing temperature was 54°C for 35 s, extension was 70°C for 40 s, and final extension was 70°C for 5 minutes. The PCR products were electrophoresed on a 2% agarose gel.Three genotypes have been observed for the FecB gene in Afshari sheep; wild homozygous (++), heterozygous (B+) and homozygous mutant (BB). All Mughani and Baluchi sheep were homozygous for this gene. A 108 bp band was detected for mutant homozygotes. A band of 213 bp was observed in wild homozygotes. The frequency of wild homozygotes was high in the three breeds,. The frequency of the wild allele in this breed was 0.39 and that of the mutant allele 0.61, the overall frequencies for the three breeds being 0.8 and 0.2, respectively. The result of Tetra-ARMS-PCR for the G1 point mutation of the GDF9 gene showed polymorphism in all three breeds, however, the frequency of wild homozygotes was high. In the Balochi breed, only two animals (4%) were heterozygous and 96% of the animals showed the wild homozygous genotype. In the Mughani breed, 16% were heterozygous and only one animal was homozygous mutant. In addition, only one heterozygote was observed in the Afshari breed. Several studies have shown the association of the FecB, FecG and FecX genes with litter size in sheep. Due to the high frequency of wild homozygotes and the fact that Mughani and Baluchi ewes mostly gave birth to single lambs, the role of FecB mutation in litter size of Afshari ewes was observed. The ram used in this herd was heterozygous for FecB. In general, it can be concluded that the mutant FecB allele has a correlation with litter size in Iranian sheep. However, the statistical confirmation of this issue requires a dedicated study with a detailed record of reproductive traits.The results of this study demonstrated the presence of a Booroola mutation in the Afshari ewes that were offspring of heterozygous rams. In addition, all of these ewes had litter size in at least one of the two pregnancies. Hence, the Booroola mutation may potentially increase the litter size of ewes. However, a more comprehensive study measuring biological indicators such as sex hormone levels, ovulation rate and follicle size is needed to demonstrate the effect of these types of mutations on increasing fertility.

Artificial and natural selection not only increases the frequency of new-useful mutations but also remains some signals throughout the genome. Since these regions often control economically important traits, identifying and tracking these regions is the most important subject in animal genetics. Also, natural and artificial selection related to adaptation and economic traits, such as litter size, results in changes at the genomic level which leads to the appearance of selection signatures. Several tests including the linkage disequilibrium-based approach, site frequency spectrum, and population differentiation-based approach have been developed to explore the footprints of selection in the genome. Domestication and selection have significantly changed the behavioral and phenotypic traits in modern domestic animals. The selection of animals by humans left detectable signatures on the genome of modern sheep. The identification of these signals can help us to improve the genetic characteristics of economically important traits in sheep. Over the last decade, interest in the detection of genes or genomic regions that are targeted by selection has been growing. Identifying signatures of selection can provide valuable insights about the genes or genomic regions that are or have been under selection pressure, which in turn leads to a better understanding of genotype-phenotype relationships. One of the best ways to understand physiological processes is to analyze gene regulation networks. Identification of genes involved in economic traits as molecular markers in breeding is of special importance. Gene regulation networks enable the researcher to study all of the genes together. This study aimed to identify selection signature regions and candidate genes related to adaptation and the number of lambs born.
To identify the signatures of selection in Iranian native sheep and Egyptian breeds, genomic information of 96 native sheep (including 96 Zandi) and 107 Egyptian sheep (including 59 Barki and 48 Rahmani) were used. The genomic information of foreign breeds was extracted from the Dryad database (https://dryad.com/articles/dataset). To determine the genotype of the samples, Illumina Bead Chip 50K was used. Quality control was conducted using the Plink software. The markers or individuals were excluded from the further study based on the following criteria: unknown chromosomal or physical location, call rate <0.95, missing genotype frequency >0.05, minor allele frequency (MAF) < 0.05, and a P-value for Hardy–Weinberg equilibrium test less than 10-6. After the quality control of the data, the hapFLK statistical method, with hapFLK v1.4 software, was used to identify selection signatures. The genomic version of the Oar_v4.0 database in NCBI was used for detecting the genomic position of single nucleotide polymorphisms (SNPs) in the sheep genome. Candidate genes were identified by SNPs located at 0.1% upper range of hapFLK using BioMart software in ensemble 109. Then, using the PANTHER database, the general biological function of the genes was checked. At this stage, it is assumed that genes that belong to a functional class can be considered as a group of genes that have some specific and common characteristics, and the QTLs in the selected region were extracted using the Animal Genome database, and the genes were compared with other research. GeneCards (http://www.genecards.org) and UniProtKB (http://www.uniprot.org) databases were also used to interpret the function of the obtained genes.
Based on the results of hapFLK, by comparing the Zandi population with Egyptian breeds (Barki and Rahmani), seven genomic regions on chromosomes 1, 2 (three regions), 10, 25, and 26 were identified. Candidate genes of DNAJB4, FNDC3B, GULP1, ACVR1, and FGF9 were in these regions. Further investigation using bioinformatics tools showed these genomic regions overlapped with the immune system, adaptation, litter size, and lipid and muscle metabolism.
The results of this study may provide an important source to facilitate the identification of genomic regions and then, the genes affecting economically important traits in the sheep industry. However, it will be necessary to carry out more association and functional studies to demonstrate the implications of these genes. Therefore, in subsequent studies with more samples and more breeds of domestic and wild sheep in Iran, a better understanding of candidate genes for important economic traits in domestic and wild species would be achieved.

Nowadays, new studies are being conducted based on the results of GWAS studies and the mapping of gene regulation networks based on the use of AWM matrix algorithms. In the present study, to map gene networks using AWM-PCIT matrix algorithms and and the association of SNPs with sheep milk production phenotypes and compositions was used. For this purpose, data on milk production traits in Valle del Belice sheep were used. After data quality control, 469 ewes and 37228 SNPs were used for final analysis. Phenotypic data were retained for analysis and contained 5586 Test day records for six milk production traits. and their gene regulation network was plotted using the cytoscape program. The results showed that using AWM-PCIT matrix algorithms, among the candidate genes that are directly and indirectly related to milk production traits were identified GENES OSBPL3, ERBB4, VGLL4, BAZ1A, DDX25, CDH23, ITSN2, DPY30, FAT3 and CAPN10. The present study and other studies have shown that the complex process of milk production and composition is important under the influence of the gene regulation network of more than 10 genes and is associated with many other genes.In total, this study supported previous results from GWAS of milk production and composition traits, also revealed additional regions in the sheep genome associated with these economically important traits. Using these findings could potentially be useful for genetic selection in the breeding programs.

Genetic architecture of sheep reproduction is increasingly gaining scientific interest due to the major impact on sheep production systems. The present study aimed to conduct for identifying the loci associated with total number of progeny born and first lambing age in highly prolific Chios sheep using the 50K arrays.

In this research, phenotypic and genotypic data related to total number of lambs born and first lambing age in lifetime and first lambing age were obtained from 538 highly prolific sheep. The gene set analysis consists basically in three different steps: the assignment of SNPs to genes, the assignment of genes to functional categories and finally the association analysis between each functional category and the phenotype of interest. Genome wide association study was performed with reproductive traits using GEMMA software. Using the biomaRt2 R package the SNP were assigned to genes if they were within the genomic sequence of the gene or within a flanking region of 15 kb up- and downstream of the gene. Finally, a gene enrichment analysis was performed with the KOBAS platform from online bioinformatics databases for the assignment of the genes to functional categories, the GO, KEGG, DAVID and PANTHER databases were used.

In this research, 11 SNP markers on chromosomes 1, 2, 5, 7, 8, 10, 13, 15, 17, 22 and 23 were identified. Also, we identified different sets of candidate genes related to reproductive traits: QULP1, AURKA, TEX12, DLG1T, ACVR1, LCP2 and PPFIA2 in Chios sheep. Some of these genes identified in this research were consistent with previous studies. In the enrichment analysis of gene sets, 19 biological pathways related to reproduction traits were identified. Some of these pathways have important role in fertilization, ovulation rate, estrogen biosynthesis, conception rate, skeletal muscle development, early development of the fetus and puberty.

The results of this research can further reveal the role of genetic mechanisms affecting reproductive traits. Considering the conformation of previous genomic region and the new genomic regions identified in this study, the findings of this research can be used more confidently in breeding programs for important economic traits in sheep.

Copy number variation (CNVs) is one of the most important structural variations in the genome which play an important role in the genetic variance of economic traits. In this study, CNVs and copy number variation regions (CNVRs) on the sex chromosome were investigated in three native Iranian sheep breeds, including fat-tailed Baluchi and Lori-Bakhtiari breeds and thin-tailed Zel breed. 50K genotyped samples were obtained and CNVs were identified for each individual using PennCNV software. After identifying CNVs in each individual, the quality control of CNVs was performed with different filters, and CNVRs were identified by using the overlapping regions of CNVs using CNVRuler software. In total, 37, 11 and 4 CNVs of gain events were identified on the X chromosome of Baluchi, Zel and Lori-Bakhtiari sheep, respectively. The minimum, maximum and average length of identified CNVs were 94477, 1293154 and 447694 bp in Baluchi breed, 271819, 906644 and 674854 bp in Zel breed and 99705, 306525 and 167913 bp in Lori Bakhtiari breed, respectively. After merging the CNVs, 30, 10 and 4 CNVRs were identified in these three breeds, respectively, all of which were of the gain events. The analysis of genes in CNVR regions showed that some of these genes (VEGF, VAM21, TRPC5, NDUFA1, APLN and TNMD) were related to fat metabolism. Annotations of genes for molecular function were significantly enriched in the pathway of arylsulfatase activity, which plays a role in reproduction. Further studies on these CNV regions can help identify genes affecting fat metabolism in sheep.

Crude protein is one of the most expensive components of feed and nutrients needed by animals. One of the ways to optimally use crude protein is to oscillating the level of crude protein in the diet and feeding it intermittently at intervals of one to several days. This study was conducted in order to investigate the effect of oscillating dietary protein concentration on growth performance and some rumen and blood parameters in fattening male lambs.

Three diets were adjusted with crude protein of 12, 14 and 16% and with the same metabolic energy. 36 male lambs with an average weight of 23.94±2.04 kg were used in four treatments in a completely randomized design. The first treatment received a diet with a crude protein level of 14%. The second to fourth treatments received diets with 12 and 16% crude protein at intervals of 24, 48 and 72 hours, respectively. Feed consumption, growth performance, feed conversion ratio, digestibility and some rumen and blood parameters were measured.

No significant difference was observed in terms of feed consumption and growth performance among the treatments, although the feed conversion ratio improved in the treatment with a 48-hour crude protein consumption interval and showed a tendency to be significant compared to the control treatment (p=0.063). The highest digestibility of organic matter was related to the treatment with 48-hour consumption interval, which shows a tendency to be significant compared to other treatments (p=0.091). No significant difference was observed between experimental treatments in terms of digestibility of dry matter, crude protein and neutral detergent fiber. The highest rumen ammonia nitrogen and blood urea nitrogen were in the treatment with 48-hour crude protein consumption interval (p<0.05).

The results of this research showed that the feed conversion ratio improves to some extent when using the method of creating oscillations the crude protein level of the ration and its intermittent feeding, but it had no effect on the growth performance of male lambs and feed digestibility, as well as rumen ammonia nitrogen and blood urea nitrogen increased. Therefore, it is recommended to use this strategy in feeding fattening male lambs.

Estrus synchronization is a valuable management tool that has been employed in enhancing reproductive efficiency in ewes. Synchronization of estrus and ovulation for fixed-time artificial insemination in sheep is mostly based on the insertion of intravaginal devices containing either progesterone CIDR (Controlled Internal Drug Release) inserts or progestagens (sponges impregnated with fluorogestone acetate (FGA) or medroxyprogesterone acetate (MAP)). Intravaginal sponges are usually inserted over periods of 12 to 14 day and used together with eCG, particularly out of season, administered at the time of sponge withdrawal or 48 hours prior to sponge removal. It has now been indicated that shortening the duration of progesterone treatment with intravaginal instruments, while being effective in inducing estrus and ovulation, reduces the incidence of vaginal infections and consequently improves fertility. On the other hands, it has been reported that pregnancy rates of progestagen-synchronized ewes were lower during anestrus than during the breeding season. Therefore, this study was conducted to investigate the reproductive performance of indigenous ewes in Khanmirza city with short-term and long-term estrous synchronization programs accompanied by eCG during breeding and anestrous season. Moreover, efficacy of estradiol injection instead of gonadotropin during short-term progesterone treatment was evaluated in both seasons. The experiment was performed at two periods, during the breeding and the anestrus seasons on 2 different groups of 400 ewes. During each season, ewes (2 to 5 years of age and average body weight of 45±2.5 kg) were allocated to 4 groups of 100, in the way that each experimental group contained an equal number of ewes of a particular age. Experimental groups were: Control (without any synchronization program), Short term-estradiol group (ewes received 12 days progesterone treatment and intramuscular injection of 1mg estradiol benzoate at the time of sponge removal), Short term-eCG group (ewes received 12 days progesterone treatment and intramuscular injection of 400 IU eCG at the time of sponge removal) and Long term-eCG group (ewes received 14 days progesterone treatment and intramuscular injection of 400 IU eCG at the time of sponge removal). The progesterone treatment consisted on a vaginal sponge which contained 60 mg Medroxyprogesterone Acetate. Then, the ewes were placed in pens and one healthy ram was introduced for every 5 ewes, in order to detect heat and mating. Estrus signs were detected and recorded every hour for 5 days. The percentages of ewes that showed overt signs of estrus during a period of five days (estrus rate), estrus onset (the time elapsed between sponge removal and the first accepted mating) and pregnancy rate (The number of ewes without showing signs of estrous after 42 days of mating/total number of ewes×100) were recorded. Fecundity and prolificacy rate was calculated based on the number of lambs born. Lambs were monitored for 30 days after birth and deaths among them during this period were recorded against the ewes which were their mothers, and the survival rate was determined. The multiple birth rate was calculated by combining the twin and triplet birth rates. The results showed that reducing the duration of treatment with progesterone sponge in both trial period (autumn and spring) led to a significant reduction in estrus rate (P ≤ 0.05), but had no significant effect on other reproductive parameters (P > 0.05). Regardless of the season, injection of estradiol instead of eCG on sponge removal day, while increasing the estrus rate of ewes, led to a sharp increase in the rate of return to estrus (P ≤ 0.05) and caused decreases in the percentage of pregnant ewes, percentage of parturition ewes and lambing rate (P ≥ 0.05). In the breeding season, the mortality rate of lambs born from progesterone-synchronized ewes decreased and fecundity increased numerically compared to the corresponding group in breeding season group. Lack of possible effect of the anestrus season during synchronization programs on estrous rate and fertility of ewes can be attributed to optimal nutritional conditions of ewes in this season. Short term progesterone treatment (12 day) as well as injection of estradiol benzoate instead of eCG is not recommended to synchronize the estrous of ewes during both reproductive and anestrus seasons. In other words, short-term progesterone treatment (12 days) was not effective to synchronize estrus in breeding and anestrous sheep which can be attributed to follicular dynamics.