The objective of this study was to determine the inbreeding depression on growth traits in Moghani sheep. Pedigree information of 8836 animals collected during the years of 1987 to 2006 by Moghani Breed Center in Jafar Abad Moghan, were used for analysis. The base population year was 1988. Analysis of the records was performed by ASReml software. Inbreeding depression was estimated as the regression of performance on the individual inbreeding coefficients via fitting an animal model. The mean inbreeding for all animals, females and males, were 0.500, 0.515 and 0.484 %, respectively. Totally, 24.22 % of all the animals were inbred. The mean of inbreeding for inbreed animals was 2.062 %. The rate of increased inbreeding per year for all animals was 0.05%. The inbreeding depression for body weight traits at birth, 3, 6, 9 and 12 months of age was, respectively, -0.007, - 0.291, - 0.026, -0.018 and -0.041 kg, per 1% increase in individual coefficient.

Tenderness is one of the important characteristics of meat and desired to consumers. Calpastatin is one of the genes which affects meat quality and growth of the animals. The aim of this study was to determine genotypic variation of calpastatin gene in Iranian Moghani sheep breed using PCRRFLP. For conducting this study, the blood samples of 176 sheep were collected. After extraction of genomic DNA, the L region of exon 1 of calpastatin gene with 622 bp was amplified with specific primers. The Mspl and Neal restriction enzymes were used to cut the PCR products. The mentioned enzymes cut the amplicons in complementary manner and alleles of M and N with frequency of 0.54 and 0.46, respectively were produced. Genetic variation (heterozygosity) in the Moghani sheep breed was moderate (0.49) and the population was in Hardy-Weinberg equilibrium. The results confirmed that the PCR-RFLP can be used to identify different genotypic variation in this breed.

The aim of this study was to investigate the effect of inbreeding on the estimation of genetic parameters of weight traits at different ages in Moghani sheep. In the present study, the information of 11721 Moghani sheep in Jafarabad Moghan breeding station from 1987 to 2011 was used. Genetic parameters were estimated using single trait model with covariate and classification and without inbreeding. CFC and WOMBAT software were used to estimate the inbreeding coefficient and the effect of inbreeding on traits, respectively. The results of analysis of variance showed that the random effect of the animal and the fixed effects of year-season, sex and age had a significant effect on all the studied traits (P <0. 05). The mean inbreeding for all animals and inbreed animal were 0. 4% and 1. 67% respectively. Totally, 26. 1 % of all the animals were inbred. The inbreeding depression for body weight traits at birth, 3, 6, 9, 12, 24, 36, 48 and 60-months of age was respectively,-1. 06, 0. 113, 0. 126,-0. 089, 0. 817,-0. 054,-0. 687, 2. 717 and-0. 139 kg, per 1% increase in individual coefficient. Direct heritability for birth weights, 3, 6, 9, 12, 24, 36, 48 and 60 months were calculated 0. 17, 0. 14, 0. 10, 0. 27, 0. 16, 0. 21, 0. 20, 0. 02 and 0. 23 respectively. The results showed that the inclusion of inbreeding in models for estimating genetic parameters had a low to moderate effect on the estimation of heritability. The results also showed that the harmful effects of excessive inbreeding could be prevented by increasing the use of distant crosses with superior males and proper genetic management in herds.

The families of TGF-b proteins are the most important growth factors in the ovary for growth and differentiation of early ovarian follicles. Three related oocyte-derived members of the transforming growth factor- b superfamily namely growth differentiation factor 9 (GDF9), BMP15 and BMPR-IB have been shown to be essential for follicular growth and ovulation. Different mutations in the GDF9 gene cause increased ovulation rate and infertility in a dosage-sensitive manner in sheep. In this study, blood samples were collected from 150 Moghani sheep breed using venojects treated with the anti-clot substance (EDTA) and subsequently their DNA content were salted out and extracted. The quantity and quality of extracted DNA was examined using spectrophotometery and gel electrophoresis, respectively. With using a pair of specific primers, the DNA fragment was amplified from exon 1 of GDF9 (462 bp). Digested PCR products with HhaI enzyme showed a G to A substiuation in GDF9 locus. The wild type allele of this gene (G/+) with two restriction site resulted DNA fragments of 156, 52 and 254 bp while the mutant allele (G/-) with one restriction site resulted two DNA fragments with the size of 52 and 410 bp. Genotype frequencies for G (+/+), G (+/-) and G (-/-) were 0.66, 0.24 and 0.1, respectively. From studied luci, GDF9 was polymorphic in Iranian Moghani sheep breed.

ntroduction: Moghani sheep breed with 2. 5 million numbers is one the most important meat breeds among fatty tail sheep. The main center for keeping this breed is Moghan plain, but there is in the regions like Meshkin Shahr, Sarab, Ardabil and the other provinces. Inbreeding also impairs growth, production, health, reproduction and survival of inbred animals. A complete pedigree is also necessary for an accurate evaluation of inbreeding and other important population parameters. This research was done for pedigree analysis, estimation of inbreeding coefficient and investigation of its effect on growth traits by regarding to importance of growth traits in economic benefit of sheep farming. Materials and Methods: Information of pedigree and growth traits (birth weight, weaning weight, 6 months weight, 9 months weight and 1 yearling weight) of available animals at breeding station of Moghani sheep were used for calculating of inbreeding and survey of its effects on growth traits of Moghani sheep. In this study, 16058 records of birth weight, 2145 weaning weight records, 2028 6 months weight records, 1319 records of 9 months weight and 1232 1 yearling weight records that were collected in 30 years (between 1987 to 2016) were used. For data preparation and editing and estimation of inbreeding coefficient Excel, Fox Pro and CFC soft wares were used respectively. For inbreeding effect analysis on related traits Wombat software and Restricted maximum likelihood method by using 12 animal models and considering of inbreeding in model as a covariate was used. The most appropriate model according to Akaike Criterion was selected. The statistical analysis of data was done by using of Duncan means test and GLM procedure of SAS 9. 2 software. Results and Discussion: In this research 48. 30 % of animals have known sire and dam. The number of records of studied growth traits with age increasing had downward trend that may cause to elimination of some lambs or not registering of data in higher ages. For all of the traits, most of the animals had zero inbreeding coefficient, so that 83. 31 % of population had zero inbreeding coefficient. 13. 50 % of all population that is equivalent with 80. 89 % of inbred population had inbreeding coefficient less than 5 %. In studied population, only 3. 19 % of all population that is equivalent by 19. 11 % of inbred population had inbreeding coefficient more than 5 %. Generation interval in four pathway including sire-son, sire-daughter, dam-son and dam-daughter was calculated 3. 15 ± 0. 053, 3. 26 ± 0. 093, 3. 46 ± 0. 015 and 3. 57 ± 0. 036 years respectively. Average generation interval of dam-progeny (3. 51 ± 0. 007 years) rather than sire-progeny (3. 21 ± 0. 064 years) was more. The shorter generation interval in sire-progeny pathway may be related to difference in replacement age of males and females. In other words, sooner replacement of males in studied herd might be one of reasons for shorter generation interval in sire-progeny pathway. The average generation interval was estimated 3. 36 ± 0. 069 years. In all of traits, the non inbreds had more average compare with inbreeds. In this study, male lambs in all traits had more average compare with female lambs that showed effects of sex on growth traits of Moghani lambs. The traits average of single lambs was more than twin lambs that may be related to more utilization of these lambs of maternal abilities. The results showed that 16. 69 % of all population were inbred. The average of total population inbreeding coefficient was estimated 0. 58 % that was in reported results range for this breed in other researches. The average inbreeding coefficient in inbred population and the highest inbreeding amount in herd was 3. 47 and 44. 67 % respectively. By evaluation of studied population form current generation to primary generation, decreasing trend in animals’ number was observed that may be related to a greater number of animals with known parents in current generation. The effective number of population was estimated 177. 37. With reducing of effective number in population, the amount of inbreeding will increase. The increasing amount of inbreeding was 0. 047 % in each year that was not significant. The inbreeding trend in studied years was positive and ascending with low swings. Average equivalent complete generations as a scale of pedigree completeness estimated 1. 60. The low amount of equivalent complete generations can be related to incomplete and low depth of pedigree. The low effective number of population resulted in decreasing of genetic variation. Inbreeding depression for 1 % inbreeding for birth weight, weaning weight, 6 months weight, 9 months weight and 1 yearling weight were estimated 5. 94, 19. 03, 20. 23, 35. 26 and 38. 74 gram that except 6 months weight and 1 yearling weight had not significant effect on the other traits. Having not a significant effect of inbreeding on birth weight, weaning weight and 9 months weight may cause to low level of inbreeding in herd and the low existence of dominance at controller genets of these traits. Regarding to the little effect of inbreeding depression on studied traits that is an optimal subject, it can be suggested by being low rate of inbreeding in this population, this trend persist in future years. Conclusion: By regarding the significant effect of inbreeding on some growth traits and for prevention of undesirable effects of inbreeding, it can be recommended an ongoing supervision be done on related parameters to genetic variation at this population to Reduce the genetic diversity caused by increased inbreeding.

The diacylglycerol acyltransferase 1 gene (DGAT1) was identified as a strong candidate gene affecting mutton quality traits in sheep. Single nucleotide polymorphism creates a single base mutation (C to T) in AGCT site of endonuclease AluI. DGAT1 is one of the candidate genes to improve carcass characteristics in feedlot animals. In order to study area T487C in exon 17 of the DGAT1 polymorphism, Iranian Moghani sheep breeds randomly slaughtered in the abattoir were recorded. DNA was extracted from 150 samples of Moghani sheep. Polymerase chain reaction to amplify 309 bp of exon 17 DGAT1 gene using a pair of specific primers was performed. Genotypes obtained from method PCR-RFLP and directly from agarose gel. Two alleles T and C with frequencies of 0.829 and 0.171 were observed respectively. Statistical analysis showed polymorphism in exon 17 region of the gene significantly correlated with carcass weight and dressing percentage (P<0.05). So that the CC genotypes of the significant mean carcass weight and dressing percentage heavier than had TT genotypes (P<0.05). Of polymorphism can be observed that improvement in breeding programs to improve carcass weight and dressing percentage through selection in favor of superior genotypes be used.

Background and objectives: The traits of economic importance such as body weight at different ages and growth rate in sheep are used as selection criteria in breeding programs. Growth can be defined either as an increase in the number of body cells or an increase in body weight and volume over a period of a lifetime. Animal growth curves can be described using various mathematical models. Growth curve components are heritable in different species. Therefore, the genetic potential of animals can be predicted for growth curve components. Thus, it is possible to change the growth curve in the population by selecting animals based on the growth curve components in breeding programs. The best function describing the growth curve can vary depending on the breed and population under study. The aim of the present study was to investigate the ability of different nonlinear models to fit the growth curve of Moghani sheep and to estimate the genetic parameters of the growth curve characteristics in this breed. Materials and methods: In the current study, the data related to the body weights of Moghani sheep collected at the Moghani sheep breeding station in Jafarabad, Moghan, during the years 1989 – 2016 were used to investigate the growth curve and estimating the genetic parameters of the growth curve characteristics in this breed. Four nonlinear models including Brody, Logistic, Gompertz, and von Bertalanffy were used to describe the growth curve of Moghani sheep. All models were fitted on the body weight records of animals at different ages using the NLIN procedure of SAS 9. 0 software. The models used have three components including A (maturity weight), B (initial weight of animal) and K (maturity rate). Goodness-of-fit indices including coefficient of determination (R2), Root-Mean-Square Error (RMSE) and Akaike information criterion (AIC) were used to select the best model. After fitting the nonlinear models and selecting the best model, the components of the growth curve of individual animals were estimated using the best nonlinear model. Then, non-genetic factors affecting the growth curve components were investigated using the GLM procedure of SAS. Six univariate animal models that differed in terms of maternal permanent environmental effects and maternal genetic effect as well as covariance between direct and maternal genetic effects were used to analyze the traits. Also, three bivariate analyzes between growth curve components were performed to estimate the genetic correlation between traits. Results: According to our results, the logistic model with the lowest MSE and AIC and the highest R2 was the best model to describe the growth curve of Moghani sheep. The estimated values for the maturity weight (A), initial weight of animal (B) and maturity rate (K) by the logistic model were 40. 328, 7. 582, and 0. 0270, respectively. The fixed effects of lamb sex, birth type, year and month of calving as well as dam age at calving had a significant effect on the components of the growth curve. Between the six fitted linear models, models number six, two and four were selected as the best models to analyze the components of maturity weight (A), initial weight of animal (B), and maturity rate (K), respectively. Direct heritability for maturity weight (A), initial weight of animal (B), and maturity rate (K) were estimated to 0. 17, 0. 08, and 0. 19, respectively. Estimates of genetic correlation obtained from bivariate analysis between AB, A-K, and B-K were 0· 06, 0· 03, and − 0· 0003, respectively. Conclusion: Among the four nonlinear models used, the logistic model had the best fit for the growth of Moghani sheep. According to the results of our study, the growth curve components of this breed had an acceptable heritability, so that these traits could be used in breeding programs to alter the growth curve and improve the growth pattern of animals in this breed.

Maternal effects on growth traits of 3872 lambs born from 182 rams and to 2274 ewes during 1994 - 2002 in Moghani Sheep Breeding Station were investigated using maternal model and restricted maximum likelihood procedures. Traits were birth weight (BWT), and body weights at 3 (BWT3M), 6 (BWT6M), 9 (BWT9M) and 12 (BWT12M) months of age. With or without taking into effect. The maternal effects, six different animal models were fitted and likelihood ratio test applied to determine the most appropriate model. For BWT, direct additive genetic, maternal additive genetic and maternal permanent environmental effects without a fitting of covariance between direct and maternal additive genetic effects were important. For this trait, estimates of direct heritability (h2a ), maternal heritability (h2m) and maternal permanent environmental variance as a proportion of the phenotypic variance ( pe2) were 0.172 ±0.022, 0.058±0.045 and 0.131±0.038, respectively. For BWT3M and BWT6M, the important sources of variations were direct as well as maternal additive genetic effects. Estimates of h2a and h2m were 0.044±0.037 and 0.075 for BWT3M, and 0.083±0.024 & 0.075±0.040 for BWT6M. None of the maternal effects influenced BWT9M and BWT12M. For these traits, h2a figures were 0.376±0.037 and 0.227±0.059, respectively. Direct additive genetic correlations varied from 0.209 (between BWT and BWT6M) to 0.604 (between BWT and BWT3M). These estimates for maternal additive genetic correlations ranged from 0.574 (between BWT and BWT6M) to 1.000 (between BWT3M and BWT6M). The corresponding estimates for phenotypic correlations varied from 0.168 (between BWT and BWT12M) to 0.843 (between BWT6M and BWT9M).