فصلنامه پژوهشهای تولیدات دامی
پیاپی 31 (بهار 1400)

This experiment was conducted to evaluate the effects of adding different levels of cinnamon powder (CNP) on production performance and egg quality traits of laying hens in wheat–based diets. In this experiment 168 White Leghorn laying hens with 60 week age and average weight of 1550 grand average production of 65% was assigned to 7 treatment with 6 replications and 4 birds each based on completely randomized design. Experimental diets were formed as follows: control diet based on wheat-soybean, control diet + 0.05% antibiotics, control diet + 0.05% xylanase enzyme ,control diet + 0.05% vitamin E, diet + 1% CNP, control diet + 2% CNP and control diet + 3% CNP. The results showed that all experimental treatments except antibiotics increased egg production compared to control treatment (P <0.05). None of the experimental treatments had a significant effect on the eggs weight. Treatments containing CNP, vitamin E, and the xylanase enzyme significantly increased the egg mass (P <0.05). Treatments containing CNP and vitamin E significantly reduced feed conversion ratio (FCR) (P <0.05). The effect of experimental treatments on most egg quality traits was not significant. The results showed that the use of 2% CNP in the diet of laying hens leads to improved performance and egg storage durability.

This experiment was conducted to investigate the effect of thyme alcoholic extract on reducing the effects of Aflatoxin and Ochratoxin on broiler chicks. In this experiment, 384 male Ross-308 broiler chicks were used in a completely randomized design with factorial arrangement 2 × 2 × 8 with 8 treatments, 4 replicates and 12 birds per replicate. The treatments were: 1: base diet (control), 2: basal diet + ppb 500 Aflatoxin, 3: basal diet + ppb 250, Ochratoxin, 4: basal diet + 0.3 percent thyme extract, 5: base diet + 500 ppb Aflatoxin with ppb 250 Ochratoxin, 6: Base diet + ppb 250 Ochratoxin with 0.3% thyme extract, 7: Base diet + 500 ppb Aflatoxin with 0.3% Thyme extract, 8: Base diet + 500 ppb Aflatoxin with 250 ppb of Ochratoxin with 0.3% Thyme extract. The results showed that adding alcoholic extract of thyme plant to broiler chickens diet would improve functional characteristics compared to controlled treatment, and that the chickens receiving alcoholic extract with Aflatoxin and Ochratoxin had better performance than Aflatoxin and Ochratoxin chicks they showed up. Meanwhile, the addition of alcoholic extract to broiler chicken diets did not show a significant difference compared to control of concentration of blood parameters, liver enzymes and internal organs weight. However, chickens that received Aflatoxin and Ochratoxin in the thyme alcoholic extract improved the concentration of blood parameters, liver enzymes, and their internal organs weight compared to those that received only Aflatoxin and Ochratoxin in the diet.

This study was conducted to evaluate the effect of multi behsil probiotic, protexin probiotic and Tetracycline supplements and feed form on performance, immune response and blood parameter of broiler chickens. A total of 960 1 day old unsexed broiler chicks (ROS 360) were randomly distributed with 4 replicates per treatment and 30 birds per replicate per cage in 2×4 factorial arrangement. The factors were two feed forms (mash and pellet) and four treatments were included control (basal diet), basal diet + Multibehsil probiotic, basal diet + Protexin probiotic and basal diet + Tetracycline. Diets were given adlibitumfrom one to 42 day of age. The result showed that the effect of feed form on feed intake, weight gain and feed conversion ratio (FCR) at different growth phases was significant (p<0.05) hence pelleted diet improve weight gain, FCR and increased feed intake compared to mash diet. Dietary supplements could significant improved broiler performance (p<0.05). Interactions between feed form and dietary supplements in the entire experiments was not significant (p>0.05). Dietary supplements had a significant effect on serum immunoglobulin M (IgM) and total (p<0.05). Multi behsil probiotic had the greatest effect.Additives did not significant effect on blood parameters in treatment, main and interaction effects (p>0.05). Considering the similar effects of these two types of probiotics, it can be recommended that Multi behsil probiotic have the ability to replace protexin probioticand Tetracycline in poultry diets.

Morphological changes in vital organs such as the liver, intestines and oviducts of laying hens by feeding certain compounds can affect their productive performance. This study was conducted to investigate the morphological changes in the liver, intestine and oviduct tissues of laying hens by feeding on omega-3 riched diets containing different levels of L-carnitine. One hundred tewnty laynig hens were used at 34-44 weeks of age. Laynig hens allocated into 2×3 factorial experiment with two levels of omega-3 (zero, 3%) and three levels of L-carnitine (zero, 100 and 200 mg/kg) in a completely randomized design with 6 treatments and 5 replicates and 4 birds per each. Diets containing 100 mg/kg L-carnitine increased the crypt width in intestinal (P<0.05). The effect of L-carnitine and omega-3 fatty acids on the diameter of the hepatocyte nucleus and the diameter of the hepatocyte cell in the liver was not significant. Feeding diets rich in omega-3s increased the height of the epithelium of the magnum (P<0.05). Adding 100 mg/kg of L-carnitine to normal or omega-3-rich diets increased fold height in Isthmus (P<0.05). It could be concluded that adding 100 or 200 mg/kg of L-carnitine to diets enriched by omega-3 fatty acids had no effect on hepatocyte nucleus and cell diameter. Diet containing omega-3 or adding 100 mg / kg L-carnitine to diet containing omega-3 had a negative effect on the height of intestinal villi but increased the height and thickness of the folds and epitelium tissue which can improve the production performance of laying hens. Further studies are recommended in this area.

In the present research the effect of different levels of chromium picolinate on performance, egg quality and some blood metabolite of laying Japanese quail at late phase of production were evaluated. Six hundered quails were allocated to 5 treatments with 4 replicates of 30 birds per replicates in a completely randomized design arrangement with repeated measurement. The experimental treatments  was consist 1) basal diet, 2)basal diet + 0.4 mg/kg chromium picolinate, 3) basal diet + 0.8 mg/kg chromium picolinate 4) basal diet + 1.2 mg/kg chromium picolinate 5) basal diet + 1.6 mg/kg chromium picolinate. Performance and egg quality traits measured four times along the experiment and analysed by repeated measurement proc. Result of this experiment showed that egg production and feed conversion ratio was affected by different experimental treatment, and quails with 1.4 mg/kg dietary chromium showed optimum performance. Dietary chromium had significant (P<0.05) effect on egg weight along the experiment and time affect the egg weight significantly. Dietary chromium had no significant (P>0.05) effect on egg quality traits such as yolk, white, shell weight, Haugh unit, shell tickness and shell weight. Serum total cholesterol, triglyceride, LDL, AST and AST was not affected by different chromium addition to basal diet. It can be concluded that inclusion of 1.4 and 1.6 mg/kg chromium to basal diet had some beneficial effect on egg production, feed conversion ratio and egg weight in laying Japanese quail.

The objective of the present experiment was the study of selenium nanoparticle (NanoSe) in freezing extender on quality parameters of frozen-thawed sperm in broiler breeder roosters reared under physiological stress. Semen samples were collected from 12 birds Ross308, 28 week-age-old, which randomly allocated 2 groups included with physiologic stress (DEX group: using the injection of dexamethasone 0.4 mg/Kg body weight, three times, every other day for 1 week) or without dexamethasone injection (CON). Subsequently, after preliminary evaluation, samples collected from CON and DEX groups were divided into 4 experimental treatments for freezing using modified Beltsville extender either with or without NanoSe. Experimental treatments were included: 1) CON: control group, 2) DEX semen sample from dexamethasone group, 3) CONNSe: inclusion of NanoSe in CON semen sample, and 4) DEXNSe: inclusion of NanoSe in the DEX semen sample. Results show inclusion of Nano selenium in extender of CONNSe improved the Total motility (TM), Progressive Motility (PM), Average Path Velocity (VAP), Straight Line Velocity (VSL), Curvi Linear Velocity (VCL), Linearity (LIN), Straightness (STR), Lateral Head Displacement (ALH) and Beat Cross Frequency (BCF) in comparison with other experimental groups (P<0.05) Also, the Viability and Integrity of sperm Membrane, Glutathione Peroxidase (GPX) and Superoxide Dismutase (SOD) activities were higher in mentioned groups then other experimental groups (P<0.05) but there were no significant differences among groups in Malondialdehyde (MDA) and Total Antioxidant Capacity (TAC) (P>0.05). While the inclusion of NanoSe had no positive effects in DEXNSe versus DEX group (P>0.05). It seems the inclusion of NanoSe in extender improves the quality of frozen-thawed sperm, while cannot compensate for the negative effects of oxidative stress.

The aim of the present experiment was to use the electron beam (beam) and alkaline hydrogen peroxide (AHP) to improve the nutritional value of date kernel powder for ruminant livestock. The date kernel powders were irradiated with the beam at doses of 0, 25, 50, 75, 100, and 125 KGy. The irradiated date kernels were then treated with 1% and 2% AHP as a 3×6 factorial experiment. Digestion and fermentation parameters of date kernel powder were measured using two-step digestion techniques and gas production methods. In comparison to the control, beam electron resulted in a decrease in NDF and ADF percentages, a significant increase in the potential of gas production, partitioning factor, truly degradable organic matter, microbial biomass production and digestibility of dry matter, NDF and ADF of date kernel (P<0.05) and the 100 KGy had the best results (P<0.05). The AHP decreased the percentage of dry matter, organic matter, and increased potential of gas production, digestibility of dry matter, NDF, and ADF of date kernel powder (P<0.05). Compared to the control treatment, the irradiated date kernel with AHP (interaction effect) caused to reduce the percentage of nutrients (except ash), increased gas production parameters, and nutrient digestibility. This decrease or increase was significant in some treatments and in some numerical or unchanged. However, for most of the parameters, the highest results were obtained during the treatment of high-dose irradiated date kernel powder (100 KGy or some cases 125 KGy) with different levels of hydrogen peroxide. Generally, the treatment by electron beam alone improved the nutritional value of date kernel powder, but the additive effect of the beam with hydrogen peroxide (interaction effect) was not considerable. Therefore, based on the results of this experiment, the best dose to improve the nutritional value of date kernel powder was 100 KGy with and without 2% hydrogen peroxide.

The experiment was conducted to investigate the effect of different ratio of palmitic acid to stearic acid in dairy cows diet. Total of 8 dairy cows (parity of 3.2 ± 0.6, milk yield of 40±3 kg/d and DIM of 56± 13) were randomly used in a 4×4 Latin square design over a 21-day experimental period. The experimental diets include different ratio of fat supplements were: 1-control diet 100P (100% palmitic acid), 2- 33S67P diet (33% stearic and 67% palmitic acid), 3-67S33P diet (67% stearic and 33% palmitic acid) and 4-100S diet (100% stearic acid). Individual dry matter intake and 3x milk production recorded at the last week of each period. Nutrients digestibility measured during 3 days of last week of experiment by collecting fecal from rectum before morning milking. The blood samples at d 19 taken from tail vein were used for metabolites and hormones analyze. The results showed that dry matter intake, digestibility of DM, fat, protein, NDF, milk and ECM yield, milk protein and lactose yield and percentage were not affected by different ratio of palmitic acid to stearic acid.  Replacing palmitic acid with stearic acid caused   decrease in FCM, fat percentage and fat/protein ratio (p<0.05). The concentration of plasma NEFA tended to be higher in cows fed 33S67P compared to 67S33P and 100S diets (p=0.07). In conclusion, present results showed that increasing diet stearic acid level led to decrease in milk fat and lactose percentage, without effects on milk yield efficiency.

The aim of this study was to evaluate effect of zinc and selenium slow-release bolus and compared to daily feeding of these elements in late pregnancy and early lactation on performance of ewes and their lambs. In the breeding season, 21 non-pregnant ewes of Mehraban breed with an average weight of 55 ± 5.2 kg and a body score of 2.5-3 were estrus synchronized using sponge. At the time of sponge removal, all ewes received 400 international units of PMSG (pregnant mare serum gonadotropin) and then crossbred with Afshar-Brola rams. 45 days before the expected date of parturition date, pregnant ewes were assigned to one of these three groups: 1) control treatment, 2) treatment of 20 mg of zinc and 0.2 mg of selenium per day in the form of a slow release bolus, 3) treatment of 20 mg of zinc and 0.2 mg of selenium per day in the form of daily feeding of salt of these elements. Zinc and selenium supplementation in both methods increases plasma zinc and selenium concentrations and the activity of glutathione peroxidase and superoxide dismutase enzymes of ewes on all test days and increased zinc and selenium concentrations in colostrum and milk (P <0.05). The amount of hemoglobin and the number of red blood cells in both groups of ewes receiving zinc and selenium were higher than the control group (P <0.05). In both groups of ewes receiving zinc and selenium, plasma concentrations of these elements and glutathione peroxidase activity increased compared to control. Maternal supplementation of zinc and selenium in both methods increased the weight of 20 and 30 days and daily weight (21 to 30 days) of lambs. In general, zinc and selenium supplementation increased the plasma concentrations of these elements and the activity of antioxidant enzymes in ewes and their lambs and improved the growth performance of lambs. No differences were observed between the two methods of blues and daily feeding. Therefore, blouses are recommended due to their ease of use.

The purpose of this experiment was to investigate the effect of activated carbon on reducing the negative effects of aflatoxin on gas production, digestibility of dry matter and organic matter of sheep diet ration under laboratory conditions. In this experiment, we assumed that activated carbon was able to reduce the negative effects of aflatoxin. This experiment was conducted in a completely randomized design with five treatments and four replicates per treatment. Expermental treatments were: 1- control (untreated diet), 2- control with methanol (control + methanol), 3- contaminated diet with methanol solution containing AFB1 at 800 ng/ml, 4- contaminated diet treated with activated charcoal at 7mg/200mg, 5-contaminated diet treated with activated carbon at 75 mg/200mg and 6-contaminated diet treated with activated carbon at 150 mg/200mg. To measure gas production and digestibility, glass bottles with a volume of 100 ml was used in a constant culture. All bottles were purged with anaerobic CO2, sealed with rubber stoppers and incubated in a water bath for 96 h at 39 degree centigrade and their gas production at 0, 12, 24, 36, 48, 60, 72, 84, 96 h incubation times was measured. The amount of gas produced was measured by means of a pressure gauge. The results showed that aflatoxin B1 treatment decreased the amount of gas production but the amount of gas production was increased in treated group as supplemented activated carbon level increased (p <0.05). Regarding the digestibility of dry matter and organic matter, there is a similar process to gas production, where aflatoxin treatment reduces both, but in treated group as supplemented activated carbon level increased the amount of them increases (p <0.05). Ammonia N concentration was highest in aflatoxin group and declined with addition of increasing level of activated carbon. Partitioning factor, microbial mass and efficiency of microbial synthesis were distinctly lower in aflatoxin group than other groups (p <0.05). However, treatments that containing high level of activated carbon had higher Partitioning factor, microbial biomass production and efficiency of microbial synthesis. It can be concluded that activated carbon has the potential to improve detrimental effect of aflatoxin on ruminal fermentation.

The design of this study was done to investigate the effects of inhibiting the activity of beta-adrenergic receptors by supplementation of different concentrations of propranolol (as a none-selective inhibitor of beta- adrenergic receptors) on some of the performance characteristics in laying hens at the end of the economic production period and the qualitative traits of eggs. The experiment was performed in a complete randomized design, over a 26-day period, using 64 laying hens (90 weeks’ age) included 4 treatments (including control treatment and propranolol treatment with concentrations of 1, 2, and 3 mg Per kilogram of live body weight) with 4 repetitions and each repetition consisted of 4 birds, and some of the performance characteristics, follicular size (F1-F5) and egg quality were measured and calculated. The data obtained from the performance characteristics show that the usage of all concentrations of this inhibitor causes the significant increase in the laying percentage, improvement of feed conversion ratio. Propranolol also significantly increased feed intake and F1 follicle size at a concentration of 3 mg. Regarding the qualitative parameters of eggs, the usage of this inhibitor causes the significant increase in the thickness of the egg shell, the significant increase in the shell weight and ratio of the shell to the total weight of the eggs and the improvement of the Hue index in concentrations of 2 and 3 mg propranolol in treated birds. Therefore, it can be concluded that supplementation of different concentrations of propranolol in this study has been capable of improving some of the performance and qualitative characteristics of eggs in laying hens at the end of the production period.

In order to evaluate the effect of silver nanoparticles coated by clinoptilolite on cytochrome P450 gene expression in broiler chicken’s liver an experiment consisting of (1) control diet, (2) clinoptilolite, (3) clinoptilolite coated with silver nanoparticles, (4) organic acids and (5) clinoptilolite coated with silver nanoparticles and organic acids in normal and heat stress conditions was designed. Liver biopsy was obtained on 21 and 42 days of experiment. Results of this study demonstrated there were no interaction between experimental treatments and heat stress conditions in chickens. As well as the expression levels of  both isoforms of CYP450 gene  in clinoptilolite treatment on day 21 and silver nanoparticles coated on clinoptilolite with organic acid treatment on day 42 of experiment in normal conditions, were significantly increased in comparison with control treatment (C) in chicken liver tissue (P<0.05). Level of CYP2C18 on  day 42 of experiment in heat stress condition in silver nanoparticles coated on clinoptilolite treatment was significantly increased in comparison with control (C) treatment (P<0.05). Whereas, the level of CYP2C23b gene expression on day 42 of experiment was not significantly different with control treatments (P>0.05) in heat stress conditions. In conclusion, results showed that the expression level of CYP2C18 isoform in liver tissue of broiler chickens was higher in comparison with CYP2C23b isoform.  The liver, as a metabolism organism in the body, identified clinoptilolite and silver nanoparticles as inorganic, chemical and exogenous substances and increased the expression level of cytochrome P450 gene acts as a biomarker for the existence of exogenous and inorganic substances in the body.

This study was conducted to investigate the influence of lipopolysaccharide (LPS) on sheep oocyte maturation and developmental competence and changes in the expression of microRNAs in cumulus cells in the inflammatory situations induced by LPS. For this, ewechr('39')s oocytes were cultured in medium containing 0 (control) and 1 µg/ml of LPS for 24 hours. After in vitro maturation, the percentage of nucleus maturation and distribution of cumulus cells were evaluated. Moreover, the rate of cleavage and blastocyst production were evaluated. The expression of microRNAs was quantitatively assessed by real-time PCR. The addition of LPS to maturation medium did not show any significant effects on the proportion of nucleus maturation and cumulus cell distribution. Although percentage of cleavage was not affected by LPS, the rate of blastocyst production was significantly reduced in the presence of LPS (P < 0.05). Expression of Mir-150 was significantly increased in response to LPS supplementation in culture medium (P < 0.05). Also, the expression of Mir-200b and Mir-27a increased in culture medium containing LPS compering to the control group, whereas Mir-let7a expression decreased in response to LPS addition, however, the difference was not statistically significant. The results demonstrate that LPS has detrimental effects on sheep oocyte developmental competence and these effects seem to be mediated through changes in the expression of microRNAs in cumulus cells.

This study was performed to investigate the effects of frankincense on growth performance, hematology, intestinal morphology, and testicular and ovarian histology in Japanese quails. The experiment was conducted with 450 Japanese quail chicks in a completely randomized design with 6 treatments and 5 replicates (15 chicks per replicate). The experimental treatments were as follows: basal diet with no additives (control treatment), and basal diet supplemented with bacitracin antibiotic (treatment 2), 1g/kg of frankincense powder (treatments 3), 2g/kg frankincense powder (treatments 4), 20 mg/kg frankincense essential oils (treatment 5), or 40 mg/kg frankincense essential oils (treatment 6). The results showed that the number of white blood cells in treatment 5 was significantly greater than those in   treatments 2 and 4 (P<0.05). The internal connective tissue layer of the testes was thicker in treatment 6 than that in the treatment 4 (P<0.05). In contrast, no significant effect of frankincense powder or essential oils on growth performance, hematology, and morphological features of the intestine, ovarian, and testes was observed as compared with the control group (P>0.05). In conclusion, the use of frankincense powder or essential oils increased the number of white blood cells but it did not change the other parameters.

Mutations during gene sequencing lead to nucleotide changes, resulting in new function in gene. The aim of the present study was to evaluate the genetic diversity and analysis the reasons for the differential expression of immune-related genes between the two populations of purebred and crossbreed Sistani and Montebeliarde cows. In this study, the results of the analysis of differential expression among the population of purebred and crossbreed Sistani and Montebeliarde cows using RNA-Seq data were used for genetic analysis and phylogenetic tree mapping. Clustal W nucleotide sequences were aligned using the MegaAlign software, and the phylogenetic tree and matrix of differences and similarities of the sequences were plotted. Based on the results of this study, the mean difference between nucleotides (nucleotide divergence) and the total number of mutations for the studied genes among purebred and crossbreed Sistani and Montebeliarde populations were in the range (2598-1869) and (3898-74) . Also, conserved regions make up a small part of the sequence of genes studied, indicating a high polymorphism of these genes and their susceptibility to nucleotide changes and mutations. The results of the phylogenetic tree for the nucleotide sequence of the studied genes showed that there is genetic diversity and divergence in the studied genes among purebred and crossbreed Sistani and Montebilliard and Indicus populations. The numerical value of the dN/dS ratio for the studied genes indicated the positive selection for these genes.

Today, reproductive problems are one of the major concerns in the dairy industry. The aim of this study was to detect the lack of function mutation of p.Q579X affecting spontaneous abortion and reproduction problems in APAF1 gene in Holstein cattle. In total, 200 blood samples were prepared and DNA was extracted with commercial kit. Then a specific pair of primers was designed to amplify a fragment with lengths of 456 bp from the exons 11 of the APAF1 gene and genotyping was performed by PCR-SSCP method. In APAF1 locus two alleles of A and B and two genotypes of AA and AB with frequencies of 96.76, 3.24 and 93.51 and 6.49 were observed, respectively. The BB genotype was not observed in the studied samples. After determining the genotype of the samples, two samples from each genotype were sequenced from both end and alignment of the obtained sequences and their comparison with the reference sequence from the gene bank to detect the mutation was carried out using BioEdit (version7.0.9.0) software. The results of bioinformatics analysis showed that the lack of function mutation of p.Q579X, which is one of the mutations affecting abortion in Holstein cattle, is present in the AB genotype of APAF1 gene in Holstein cattle in Iran. Given that this mutation causes abortion in cow in homozygous form, the results of this study can be directly used in breeding programs in order to identify the carriers of this mutation and culling them from Holstein dairy herd.

The samples of honeybee workers were collected from 26 areas from Iran. The aim of this research was to evaluate the ND1 (630 bp) and ND5 (630 bp) genes for differentiation of Iranian honeybees (A. m. meda) from commercial subspecies (A. m. carnica, A. m. ligustica, A. m. caucasica and A. m. mellifera). The ND1 and ND5 squences of Iranian honeybees and other honeybee subspecies were evaluated using bayesian and parsiminy methods. ND1 and ND5 showed eight and five haplotypes in populations of Iranian honeybees. Using bayesian method, four clades were identified in Iranian honeybees of phylogenetic tree derived from ND1 gene. The first to fourth clades included haplotype 1 (Golestan, Southern Khorasan, Kordestan, Lorestan and Mazandaran), haplotype 2 (Siatan Balochestan), haplotype 3 (Yazd and Eilam), haplotype 4 (Ardabil), haplotype 5 (Kerman), haplotype 6 (Zanjan), haplotype 7 (Kermanshah) and haplotype 8 (Boshehr, Western Azarbayejan, Charmahal Bakhtiari, Qazvin, Qom, Hamadan, Hormozgan, Razavi Khorasan, Northern Khorasan, Kohkeloye Boyerahmad, Khozestan, Markazi, Semnan and Fars). The phylogenetic trees drived from bayesian and parsimony methods demonstrated more ability of ND1 gene in comparison with ND5 gene; ND1 gene differntiated Iranian honeybees from commercial honeybee subspecies. Furthermore, using parsimony method, more informative sites were identified in ND1 in comparison with ND5 gene. Principle component analysis (PCA) confirmend phylogenetic trees of ND1 drived from bayesian and parsimny methods and phylogenetic tree of ND5 drived from bayesian method. Moreover, PCA demonstrated more efficiency of ND1 in differentiation of evolutionary lineages (Z-subgroup, A, C and M) in comparison with ND5 gene.

The heat shock proteins (HSPs) are a family of proteins contributing to cellular resistance against a variety of thermal stresses in different climates. In this study we aimed to characterize polymorphisms of the ovine HSP70A1A gene in Mehraban indigenous sheep breed and Romanov imported sheep breed, because they are well adapted to the cold climate. Blood samples were collected from a total of 141 sheep (100 Mehraban and 41 Romanov), and then genomic DNA was extracted according to conventional instructions. Polymerase chain reaction (PCR) was performed to amplify the 247 bp and 298 bp of the exon region of the HSP70A1A gene (Oar_v4.0; Chr 20, NC_019477.2). Also, polymorphisms of the studied fragments were explored using single strand conformational polymorphism (SSCP) technique and then the amplified DNA fragments were sequenced by Sanger sequencing method. In both Mehraban and Romanov breeds, five distinct SSCP patterns were identified that two and three electrophoretic patterns were respectively related to 247 bp segment and 298 bp segments. Furthermore, frequencies of SSCP patterns showed no differences between breeds. Five single nucleotide polymorphisms (SNPs) including g.26562252C>A, g.26562261G>C, g.26562270T>C, g.26562273C>T and g.26562279C>T were identified in 247 bp segment, and also, three SNPs including g.26561745T>C, g.26561784C>T and g.26561877G>A were identified in 298 bp segment of PCR products. Results revealed that all SNPs were in Hardy–Weinberg disequilibrium (p < 0.05), except of g.26561745T>C and g.26561877G>A. Considering the role of HSPs in resistance to the environmental stresses, it can be conclude that the identification of  these SNPs can  play an important role on understanding the mechanism of adaptation  to temperature tolerance among the Iranian indigenous sheep breeds.

In order to estimate the genetic parameters and heritabilities of growth traits and Kleiber ratios in Moghani sheep, data collected in Jafarabad-e-Moghan station from 1994 to 2016 were used. Investigated traits including birth weight, average daily gains and Kleiber ratios during four time periods that is birth to 3 months, 3 t 6 months, 6 to 9 months and 9 to 12 months first analyzed by SAS 9.2 software to indicate the significant fixed effects, finally, 6 animal models running by Wombat software was used to estimate the genetic parameters and heritabilities. The heritability of birth weight (0.31), Average daily gain and Kleiber ratio from birth to 3 months and from 3 to 6 months (0.34, 0.36, 0.40 and 0.38 respectively) were medium to high. The maternal heritabilities and the ratios of maternal permanent environmental variance to the total variance were in the range of 0 to 4 percent and 0 to 2 percent respectively. The genetic trend for birth weight, Average daily gains and Kleiber ratios during four time periods were 0.13, 0.21, 0.27, -0.0000014, 0.01, 0.01, -0.0002 and 0.00004 respectively. These results indicated the relative efficiency of breeding programs for the average daily gains and Kleiber ratios during birth to 3 months and 3 to 6 months in Moghani sheep.

This study was carried out in order to investigate the management and efficiency of dairy farms units and milk production function, in 121 units of dairy farm in Lorestan province at the year 2017. The Required data was collected with field survey and face to face interview method. Data of production function were estimated using corrected ordinary least squares (COLS) Method by Cobb Douglas functions. Also, technical efficiency was estimated by deterministic parametric frontier (DPF). In terms of dairy farms units cost, feed costs accounted for 65.5 %, labor costs 16.16 %, health care and insemination 9.9 %, and 9.1% other costs (including the cost of losses, location and maintenance of dry cows). The average technical, allocative, economic efficiency of the units were 64.3, 52.4 and 44.3% respectively, that showed the significant potential of these units in increasing their productivity. Based on this results farms were not desirable condition in terms of economic efficiency, similar with allocation efficiency in contrast to the technical efficiency. The results showed that dairy cattle units were not efficient 75.7 percent economically in Lorestan province and failed to optimally and effectively minimizing inputs cost. Milk production function results showed that consumption of alfalfa, corn silage, concentrates, artificial insemination number a positive and very significant effect (P<0.05)  and number of workers, hygiene and health costs also fuel and electricity consumption had a positive and significant effect on milk yield (P<0.05). The results of milk production function showed that the importance of increasing each unit of the concentrate (0.352) in increasing milk production was more than other inputs. Generally, the majority of dairy farms due to lack of observance of economic principles in the management of inputs had a low allocation and economic efficiency. Finally, according to the obtained results, it is necessary to implement the guaranteed milk price and maintain the relative stability of forage and concentrate prices in increasing milk production of dairy farms units in Lorestan province.