Extended Abstract Introduction and Objective: Genetic diversity determines the capacity of a population to respond to selection and genetic improvement. In order to evaluate the breeding programs ...carried out on a population and decide to continue it, it is necessary to evaluate the genetic diversity of that population. The purpose of this project was to investigate the genetic diversity and estimate the population parameters of sanjabi sheep based on the analysis of their pedigree information. Material and Methods: The information used in this study included animal number, father number, mother number, sex and date of birth of 2067 purebred sheep that were collected in Mehrgan station during 2009 to 2022. Pedigree analysis was performed on the entire population or a reference population in order to estimate population parameters such as inbreeding coefficients, increase rate of inbreeding, effective population size, generation interval, effective number of founders and effective number of ancestors. Results: The generation interval and the average relationship were estimated as 2.87 years and 0.43%, respectively. The average inbreeding in the entire population was calculated as 0.48%, which indicated the low level of inbreeding in this population. The trend of inbreeding changes during the studied years was unfavorable. The effective size of the population was estimated to be 260.86 using the increase of individual inbreeding and the method of the maximum number of generations. The effective size of the founder was estimated to be 272.60, which indicated the balanced participation of the base population in reproduction. The effective number of founder individuals (fe) and the effective number of ancestors (fa) were equal to 109 and 100 heads, respectively. The fe/fa ratio was calculated as 1.09, which indicated the low effect of genetic bottlenecks. 50% of the total genetic diversity was created by 38 heads of ancestors, which indicated the balanced participation of ancestors in creating the genetic diversity of the next generation. Conclusion: The results showed that despite the small and closed population, there is relatively high genetic diversity among the individuals. Since the loss of genetic diversity and increase in homozygosity will lead to a decrease in production performance, it is necessary to prevent the reduction of genetic diversity and its adverse effects in the future by examining genetic diversity and and making decisions to preserve it
A trial was conducted to investigate the effects of dietary Coriandrum sativum seeds on carcass performance, immune system, blood metabolites, rumen parameters and meat quality of Lambs. 16 Sanjabi ...lambs of 27 ± 5.1 kg during post-weaning (97 d of age) period were randomly selected. Four diets including 0, 1, 3, and 5% coriander seeds, replaced by Alfa alfa in the diet, were considered. A 30:70 alfalfa hay: concentrate diet for a period of time (97 to 187 d of age) was used. The results showed that feed intake was significantly increased by adding coriander seeds, linearly. There was no significant difference for apparent digestibility of crude protein, crude fat, neutral and acidic detergent fiber, crude ash, rumen fluid pH and ammonia nitrogen at 0, 2 and 4 h after feeding, Meat dry matter, ash, crude protein and fat, and the meat’s fatty acid profile (p > 0.05). Dietary coriander seeds had a significant effect on neutrophils, lymphocytes, monocytes and eosinophil’s (in days 7 and 14 of trial) and blood metabolites at the middle of trial. Obtained results suggested that supplementation of coriander seed may have limited effects on nutrient digestibility, ruminal parameters, meat quality, blood cells and metabolites.
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•Incorporating QTL information will increase the accuracy of breeding value.•At position 235 cM on chromosome 1, one QTL affecting weaning weight identified.•The QTL found in this ...study could be related to muscle depth gene.•Validation of this QTL helps to select higher genetic potential rams and ewes.
This study aimed to detect the quantitative trait loci (QTL) which affecting the growth traits in some parts of chromosomes 1 of Sanjabi lambs. The study population consisted of six groups of fathers which had an average of 39.17 lambs. Initially, the fathers were genotyped for eight microsatellite markers on chromosome 1, and the offspring of the heterozygote fathers were genotyped. The quantitative traits were the body’s weight at birth, 3, 6, 9, and 12 months, which were corrected for the fixed effects of year of birth, sex, and birth type. QTL search was performed by interval mapping based on a regression model for each cM (Centimorgan) of the chromosomes. In total, one QTL in the 235 cM of chromosome 1 was identified from the beginning of the chromosome in associate with weaning weight. The sire substitution effect for both families was 2.14 kg. The confidence interval estimation of the detected QTL that was estimated using the Bootstrap method was 225–238 cM of chromosome 1. This QTL was determined between the MCM137 and MCM130 markers and at a distance of about 9 cM from the MCM137 marker. If this QTL was approved in the next research, it can be used in Marker-assisted selection programs. In this case, more accuracy should be achieved for the evaluation of superior animals.
In the climatic conditions of the country, due to the large volume of groundwater abstraction by wells and also considering the number of wells drilled, especially in recent years, the calculation of ...privacy in order to apply proper management on the conservation and optimal use of groundwater resources is of particular importance. In this regard, one of the issues that concerns those involved in groundwater protection is the density and proximity of exploitation wells on the one hand and overdraft by exploiters on the other hand. Therefore; in this research, at first, the well function was solved mathematically and the impact radius of each well in the two modes of application of corrective discharge (based on the area under cultivation) and case discharge (exploitation license discharge) was obtained. Then the radius map of the impact of the total wells in the area was drawn and then the areas with privacy interference were identified and drawn. Based on the obtained results, the average discharge of all exploitation wells in the corrective and case discharge mode was calculated to be 18.37 and 11.14 l/s, respectively was obtained. The results also showed that in the most optimistic case, about 20% of the total aquifer area has privacy interference.This causes the local wells to undergo simultaneous operation, severe localized cones and the aquifer to be subjected to unusual stresses, which in the long run causes a permanent and lasting decline in the aquifer and in the long run results to subsidence of the ground.
In the sheep farming industry, breeders need suitable strategies in order to improve milk yields. Meanwhile, silymarin (a natural hepatoprotector substance) has beneficial effects on common oxidative ...stress at the beginning of lactation. This study was the first research to evaluate the effect of silymarin on milk production, liver enzymes, oxidative and HSP70 responses in the postpartum period. Total 20 Sanjabi ewes were divided into two groups: control (group C: no addition) and treated (group T: received a diet supplemented with silymarin at 2000 mg/kg feed for 15 d after lambing). Data indicated that silymarin reduced postpartum body weight(BW) loss. At the same time, the feed intake (FI) rate increased. In addition, the peaks of milk yields could be achieved earlier compared with control ewes (P< 0.05). Treatment decreased milk compositions (fat and protein) on days 10 and 15. Furthermore, the reactive oxygen species (ROS) and malondialdehyde (MDA) contents in group T were significantly lower than group C (P< 0.05). Also, the activities of endogenous antioxidant enzymes (Glutathione peroxidase, Superoxide dismutase, and Catalase) were increased. Silymarin remarkable increased the serum alanine aminotransferase (ALT) values (P< 0.05). Meanwhile, an increasing trend in the total protein levels was recorded in group T as compared to group C (P> 0.05). The QRT-PCR analysis showed that silymarin supplemental reduced expression of HSP70 gene in blood serum (P< 0.05). It means that changing the diet can affect the activity of heat shock proteins that consequently changes the quality of animal products. In conclusion, our observation relieved that silymarin treatment in the puerperium periodis potentially an effective strategy to improve milk quality via dual hep at oprotective and antioxidant functions.
In this study, semen samples were collected from 96 Sanjabi rams in order to investigate the IGF-1 gene polymorphisms and their relationship with the characteristics of semen quality and testicular ...size. The dimensions of scrotal length, width and circumference were measured during autumn and spring over two years. Blood samples were simultaneously collected from jugular vein to extract DNA. PCR was performed using specific primers to amplify 294 and 272bp fragments including 5′ regulatory region and exon 3 of IGF-1 gene, respectively. PCR products were digested by BFOI and Eco88l restriction enzymes, respectively. Two genotypes including AA (194 and 100bp), AB (294, 194 and 100bp) and all possible genotypes including CC (182 and 90bp), CT (272, 182, and 90bp) and TT (272bp) were observed for 5′ flanking region and exon 3 of IGF-1 gene, respectively. The significant differences among IGF-1 genotypes for testicular dimensions were not observed. However, the polymorphism of 5′ flanking region in the studied population had significant effect on individual motility and percent morphology traits. Animals with AB genotype had significantly higher individual motility compared with AA genotype (P < 0.05). Also, animals with AA genotype had significantly the highest percent morphology compared with AB genotype (P < 0.1). The exon 3 of IGF-1 gene had significant effect on individual motility, concentration, morphology and water test traits. Animals with CT genotype had the highest sperm concentration (P < 0.1) and water test (P < 0.05) compared to CC and TT genotypes. Moreover, animals with TT genotype had significantly the highest percent morphology compared with other genotypes (P < 0.05). Briefly, the results indicated that individual motility, concentration, percent morphology and water test traits could be in association with IGF-1 genotypes. It might be concluded that polymorphisms in IGF-1gene can be considered to develop male fertility in future and for using in selection process of better animals under masker assisted selection programs.
•Mutations at IGF-1 gene were identified in Sanjabi breed rams.•The significant differences among IGF-1 genotypes for testicular dimensions were not observed.•The 5′ flanking region polymorphism had significant effect on individual motility and percent morphology traits.•The exon 3 mutation had significant effect on individual motility, concentration, morphology and water test traits.•We suggest more consideration to IGF-1 as a potential gene in order to improve ram fertility.
This study was conducted to determine the effect of dietary supplementation of organic zinc (Availa
®
Zn100) and selenium (Availa
®
Se1000) on semen characteristics, testes measures and serum ...testosterone concentration. Twenty Sanjabi rams (50.01 ± 5.6 kg) were randomly divided into four equal groups, given the basal diet as control (C) or supplemented with 0.3 mg/kg Se (SE) or 40 mg/kg Zn (ZN) or 40 mg/kg Zn plus 0.3 mg/kg Se (ZS) for 120 days experiment (from July to November). The semen samples and blood samples were collected every 3 weeks and scrotal circumference was measured every 15 days. The results indicated that scrotal circumference and testosterone concentrations did not differ due to treatment (P > .05). In contrast, semen characteristics were affected by ZS supplementation. The sperm density and total sperm number increased (P < .05) in ZS group. In addition, the progressive sperm motility was higher in ZS (P < .05) than those of SE and C groups. It is concluded that ZS treatment can improve semen characteristics, which may result in overall improvement in reproductive performance of treated Sanjabi rams during the breeding season.
•Two polymorphisms located at leptin gene were identified in Sanjabi sheep rams.•Population indexes showed high potential of the loci for using in selection programs.•The 170G>A locus had significant ...effect on individual motility, water test and SC traits.•The 332G>A locus had a significant effect on viability trait, water test and SC traits.•The study suggests using leptin as a potential gene in order to improve fertility.
The purpose of this study was to investigate leptin gene polymorphisms and their relationships with the characteristics of sperm quality and testicular dimensions. Semen samples were collected from 96 Sanjabi rams during autumn and spring seasons over two years. Simultaneously, the dimensions of length, width and scrotal circumference were measured. Blood samples were taken from the jugular vein to extract DNA. PCR was performed to amplify a 463bp fragment including exon 3 of leptin gene. PCR products were digested by Bcnl and Cail restriction enzymes to identify 170G>A and 332G>A mutations in exon 3, respectively. Leptin gene polymorphism in 170G>A locus had an effect on individual motility trait, water test and scrotal circumference (P<0.05) and animals with the AA genotype had the highest individual motility compared with the GG and GA genotypes (P<0.05). The AG genotypes had the highest water test compared with the GG and AA genotypes (P<0.05) but GG genotype had higher scrotal circumference than that of GA and AA genotypes (P<0.05). The results showed that polymorphism in 332G>A locus had a significant effect on viability trait, water test and scrotal circumference as GA genotypes had the highest amounts for these traits compared with GG genotypes (P<0.05). Based on our knowledge, the current study is the first report on the association of leptin gene polymorphisms with sperm fertility and testicular dimensions in sheep, which suggests leptin gene as a potential gene to be used in breeding programs in order to improve fertility in herds.
Genetic parameters for growth traits and Kleiber ratio were estimated in Sanjabi sheep. Data collected from 1992 to 2002 in Mehregan Breeding Station in Kermanshah province at west of Iran were ...analyzed. Studied traits were birth weight (BW), weaning weight (WW), six-month weight (6MW), nine-month weight (9MW), yearling weight (YW), average daily gain from birth to weaning (ADG1), Kleiber ratio from birth to weaning (KR1), average daily gain from weaning to six months of age (ADG2) and Kleiber ratio from weaning to six months of age (KR2). (Co)variance components were obtained fitting different animal models using restricted maximum likelihood (REML) procedure. Akaike information criterion (AIC) was applied to determine the most appropriate model for each trait. Model including maternal genetic effects as well as direct genetic effects, without considering covariance between them, was chosen as the most appropriate model for BW, ADG1 and WW. For KR1 and 6MW the model including permanent environmental effects due to ewe over direct genetic effects was the most appropriate one. Model which included only direct genetic effects was the most suitable model for other traits (9MW, YW, ADG2 and KR2). Direct heritability estimates of 0.09, 0.15, 0.09, 0.19, 0.11, 0.14, 0.08, 0.15 and 0.07 were obtained for BW, WW, 6MW, 9MW, YW, ADG1, ADG2, KR1 and KR2, respectively. Maternal heritabilities for BW, ADG1 and WW were estimated as 0.14, 0.23 and 0.24, respectively. Ratios of phenotypic variance due to maternal permanent environmental effects were 0.11, 0.21 and 0.16 in respective order for BW, KR1 and 6MW. Estimates of direct genetic correlation among studied traits were very low to high in magnitude and varied from −0.00 for BW–KR2 to 0.99 for WW–6MW, ADG1–YW and ADG2–9MW.
The effect of an ad libitum supplementary feeding on some reproductive characteristics of ram lambs were evaluated. Twelve Sanjabi rams were allocated to one of two groups: control (C) and treatment ...(T). The control group received hay and the treatment group received hay and concentrate with gross energy and crude protein concentration of 4.52 Mcal and 16% of dry matter, respectively. At the end of experiment, after taking blood samples for determination of testosterone concentration (TC), all lambs were castrated and the testicular weight (TWT), testicular volume (TV), testicular length (TL), and testicular width (TW) were measured. In addition, testes were subjected to histological analysis. Body weight (BW), TC, TWT, TL, and TV in the T group were higher (
P
< 0.05) than the C group. However, TW was not affected by diet (
P
> 0.05). Animals from the C group presented lower numbers (
P
< 0.05) of Sertoli (SCN), germ (GCN), and Leydig cell numbers (LCN) compared to the T group. Also, seminiferous tubule diameter (STD) in the T group was significantly greater than (
P
< 0.05) the C group. TWT had a significant association with TC (
P
< 0.05), STD (
P
< 0.01), SCN (
P
< 0.01), GCN (
P
< 0.05), and LCN (
P
< 0.05). TC was correlated with STD (
P
< 0.01), SCN (
P
< 0.01), GCN (
P
< 0.05), and LCN (
P
< 0.05). STD showed close correlation with SCN (
P
< 0.01), GCN (
P
< 0.01), and LCN (
P
< 0.05). Also, SCN had a positive association with GCN (
P
< 0.01) and LCN (
P
< 0.05). A positive correlation was found between GCN and LCN (
P
< 0.01). In conclusion, the plane of nutrition of growing ram lambs enhances their growth and testicular development and probably will increases their postpubertal reproductive performance.
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