Mina Kooshesh; Mohamad Salarmoini; Mohsen Afsharmanesh; Hadi Tavakkoli
Abstract
This experiment was conducted in a completely randomized design with 5 treatments, 4 replicates and 10 Ross 308 broiler chicks per replicate. The treatments consisted of: 1) control (basal diet) 2) basal diet + supplemented with 600 mg/kg antibiotic flavophospholipol 3, 4 and 5) chicks fed basal diet ...
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This experiment was conducted in a completely randomized design with 5 treatments, 4 replicates and 10 Ross 308 broiler chicks per replicate. The treatments consisted of: 1) control (basal diet) 2) basal diet + supplemented with 600 mg/kg antibiotic flavophospholipol 3, 4 and 5) chicks fed basal diet but 5, 10, and 15 gram/ liter Aloe vera gel added to their drinking water, respectively. In the whole of the experimental period, the treatments did not have any significant effect on body weight gain, feed intake, feed conversion ratio, and European efficiency factor in broilers (P>0.05). Intestinal microbial population (Escherichia coli, Lactobacillus) was not affected by the experimental treatments (P>0.05). Blood metabolites included cholesterol, triglyceride, high-density lipoprotein, low-density lipoprotein, albumen and alkaline phosphatase were not affected by the experimental treatments (P>0.05), except serum glucose level which significantly reduced in birds received 15 gr /liter Aloe vera jel compared to the control (p < 0.05). Effect of the experimental treatments on the antibody titers against sheep red blood cells at 28 and 42 days of age were not significant (P>0.05). Also, in the case of white blood cells, the heterophile and heterophile to lymphocyte ratio were increased in the bird received different levels of Aloe vera (p < 0.01). In general, the use of the Aloe vera gel could improve immune response.
Ahad Khasali aghtaei; Mehdi Vafa Valleh; Hossein Moradi Shahrebabak; Golamreza Dashab
Abstract
The present study was carried out to estimate levels of genomic inbreeding based on ROH (FROH) analysis in the two Iranian native cattle populations including Sarabi and Najdi, as well as comparing the FROH estimates with other inbreeding estimates obtained based on the genomic relationship matrix (FGRM), ...
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The present study was carried out to estimate levels of genomic inbreeding based on ROH (FROH) analysis in the two Iranian native cattle populations including Sarabi and Najdi, as well as comparing the FROH estimates with other inbreeding estimates obtained based on the genomic relationship matrix (FGRM), percentage of homozygous SNPs (FHOM) and pedigree information (FPed). To do this, 213 and 211 samples were randomly selected from Sarabi and Najdi populations, respectively. The samples were genotyped using the Illumina BeadChip40K v2 microchip. In addition, 30 samples of Holstein dairy cattle of Iran provided by Animal Breeding Center of Iran, were included in the analysis . Genomic analysis was performed using CFC, Excel, Plink, SNeP programs. A total of 2030 haplo-blocks were identified in the populations. The highest and lowest number of ROH segments (ROHs) was observed within Najdi and Sarabi Population, respectively. Furthermore, ROH length were found to be significantly different among breeds (p < 0.05). Najdi population had the highest number of ROH across different categories of ROH length (4-8Mb, 8-16Mb and >16Mb). Maximum correlation coefficient among the estimated inbreeding coefficients was obtained between FPed and FROH>4Mb (0.592) in the Sarabi population (p < 0.001). The results of this study indicate that presence of inbreeding at least in the five early generations of the studied native populations and the conservation programs must be taken to manage the inbreeding levels in both populations.
M. Gholizadeh; Jamal Fayazi; Reza Valizadeh; Hamed Hamed Kharrati Koopaee; Gholam Reza Dashab
Abstract
In this study, the polymorphism of four microsatellite loci BMS1350, LGB, ILSTS45, and BMS1915 in chromosome 3 and their association with wool trait were investigated in Baluchi sheep. DNA extraction was performed from blood samples of 185 Baluchi sheep from Abbas Abad Breeding Station. Gene fragments ...
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In this study, the polymorphism of four microsatellite loci BMS1350, LGB, ILSTS45, and BMS1915 in chromosome 3 and their association with wool trait were investigated in Baluchi sheep. DNA extraction was performed from blood samples of 185 Baluchi sheep from Abbas Abad Breeding Station. Gene fragments of microsatellites were amplified by polymerase chain reaction with specific primers. The result shown allele E in BMS1915 locus with 0.40, Allele D in BMS1350 locus with 0.30, Allele B in LGB locus with 0.48 and Allele A in ILSTS4 locus with 0.46, had the highest frequency. The results of the Comparison of mean shown the LGB locus has the highest and ILSTS45 locus has the lowest production. Also, genotype AC in the LGB locus highest (1308 ±95.7) and genotype BC had the lowest (875 ± 54.7) of production. By comparing the coefficient of variation 4 loci founded that the greatest diversity and dispersion associated with the ILSTS45 and the lowest diversity associated with BMS1350 locus. Chi-square test (χ2) shown all of the microsatellite loci were in the Hardy-Weinberg equilibrium (P>0.05). Association analysis of polymorphism these loci shown there is no significant association between polymorphism of these loci and wool trait in Baluchi sheep (P>0.05). Statistical analysis showed there was no significant difference between loci polymorphisms and wool traits. Therefore, concluded in further research on selected studies based on molecular markers, the relationship between these loci and other traits in the Balochi sheep can be examined.
Hassan Darmani Kuhi; Hassan Darmsni kuhi; Maziar Mohiti
Abstract
This experiment was conducted in order to evaluate the effect of dietary unsaturated (soybean oil) to saturated (palm fat) fat ratio and Zataria multiflora essential oil (ZMEO) on performance, gut microbial and carcass oxidative stability of Japanese quails. A total number of 600 one-day-old male and ...
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This experiment was conducted in order to evaluate the effect of dietary unsaturated (soybean oil) to saturated (palm fat) fat ratio and Zataria multiflora essential oil (ZMEO) on performance, gut microbial and carcass oxidative stability of Japanese quails. A total number of 600 one-day-old male and female Japanese quails were allocated to 6 dietary treatments in a completely randomized design with a 2 × 3 factorial arrangement during the experimental period (1 to 42 days). Dietary factors were three different ratios of unsaturated to saturated fat (US/SF( of 100 to 0, 75 to 25 and 50 to 50 and two levels of ZMEO (0 and 0.03% of diet). Each treatment was replicated five times with 20 birds per replicate. Chicks fed diets supplemented with ZMEO had higher body weight gain, lower feed intake and better feed conversion ratio compared to the control group (p < 0.05). In spite of a significant reduction in abdominal fat pat, the effect of ZMEO addition on the relative weight of other carcass parts was not significant (p>0.05). The lowest and highest count for Escherichia coli and Lactobacillus were belong to ZMEO supplementation group (p < 0.05). Use of ZMEO led to significant reduction in TBARS concentration in breast meet (p < 0.05). Different ratios of US/SF were not affected the performance, gut microbial populations and breast meat quality. Dietary utilization of different ratios of US/SF with ZMEO led to significant increase in body weight gain, Lactobacillus population and significant reduction in abdominal fat and TBARS concentrations in the breast meat.
iman hajkhodadadi; Hossein Ali Ghasemi; mahdi kazemi; mahdi khodaee motlagh
Abstract
The effects of enzyme and age of ostrich were evaluated on performance and nutrient digestibility in African ostrich chicks. There were two treatments as follows; common or control diet without enzyme (Treatment 1), control diet plus multi enzyme (0.5 gkg -1) (Treatment 2). The experiment conducted with ...
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The effects of enzyme and age of ostrich were evaluated on performance and nutrient digestibility in African ostrich chicks. There were two treatments as follows; common or control diet without enzyme (Treatment 1), control diet plus multi enzyme (0.5 gkg -1) (Treatment 2). The experiment conducted with 16 male ostrich chicks (8 birds per treatment) and completely randomized design was used in this experiment. Performance traits were initial weight, average daily gain and final body weight. The diets and feces composition such as dry matter, crude protein, ether extract, crude fiber, neutral detergent fiber and acid detergent fiber was determined based on AOAC methods in 10 and 12 month age of ostrich. Acid insoluble ash (AIA) and acid detergent lignin (ADL) were measured in feed and feces as internal marker. There was significant effect of enzyme was detected on performance traits, feed intake, dry matter intake parameters (P>0.05). With increasing age of ostrich from 10 to 12 month, digestibility of DM, CF, NDF and NFC were increased. Enzyme in diet could not significantly increased the digestibility of Crude fat (EE) and NFE (69.79 % vs. 74.31 % for CP and 67.25% vs. 71.55 % for NFE. Generally, the use of Enzyme (0.5 g/kg) in diet was particularly effective to improve performance traits and nutrient digestibility, especially DM, OM, CP, CF, NDF, ADF and NFC in growing ostrich chicks.
Masume Nazari; A. Rashidi; M. Razm Kabir; A. Sadeghi-Sefidmazgi; Mazdak Kazemy
Abstract
The aim of the present study was evaluation of genetic- economic merit for imported Holstein bull semen daughters in different climates of Iran. These progenies were categorized based on different selection indices of their sire semen exporter countries. In this study, data were milk, fat and protein ...
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The aim of the present study was evaluation of genetic- economic merit for imported Holstein bull semen daughters in different climates of Iran. These progenies were categorized based on different selection indices of their sire semen exporter countries. In this study, data were milk, fat and protein yield, calving age and calving interval in the first lactation of 270566 Holstein cattle that were collected during 1993-2017 at Animal Breeding Center of Iran. The daughters breeding values were predicted under multi-trait animal model by DMU software. The genetic-economic merit of progeny was estimated using the Lifetime Net Income (LNI) index. Estimated least square means of the LNI index for daughters of imported semen under different selection indices were statistically significant in the various climates (p < 0.01). The highest estimated least square mean of LNI index in Iran was related to daughters whose sire semen came from France bulls (2001- 2011). The results obtained in this study showed that the highest estimated least square means of LNI index in cold, semi-cold, moderate and warm climates were related to daughters whose sires were imported from Germany (2008- 2013), France (2001- 2011), France (2012- 2013) and the Netherlands (2012- 2013), respectively. Thus, it could be concluded that the genetic-economic merit of daughters from imported semen in each climate depends on the selection index of bulls in the semen exporter country.
reza behmaram; Azar Rashedi Dehsahraei
Abstract
For doing this study 6841 body weight records at different ages of 1877 Makooei sheep which were collected at Makooei sheep breeding station in Maku city of West Azarbaijan province was used. Parameters of growth curve based on body weight at different ages and different initial amounts using NLIN procedure ...
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For doing this study 6841 body weight records at different ages of 1877 Makooei sheep which were collected at Makooei sheep breeding station in Maku city of West Azarbaijan province was used. Parameters of growth curve based on body weight at different ages and different initial amounts using NLIN procedure of SAS software were estimated. Four non-linear models including Brody, Von-Bertalanffy, logistic and Gompertz, were fitted on data. After setting the most appropriate describing non-linear growth curve, using by Gauss-Newton repeat method fitted in way that growth curve parameters obtained separately for all individuals. Using GLM procedure of SAS software, effective fixed effects on these parameters were identified. The Brody model with having the highest accuracy (R2 = 0.955432) and lowest error (MSE = 37.78) was recognized as the best model for describing growth pattern of Makooei sheep. The year and season of birth, lamb sex and birth type had significant effect on mature weight and growth rate (P < 0.01) but lamb sex on mature rate was not significant (P < 0.01). The results showed that, compared with the other evaluated models, for fitting growth curve of Makooei sheep was more suitable.
masoud mostashari; aliasghar sadeghi; Saeed Esmaeilkhanian; jafar ahmadi
Abstract
The aim of this study was to investigate the effects of adding betaine to diets of Ross and Arian strains that received drinking water with total concentration of TDS. 720 single-day broiler chicks, Ross and Arian strains were distributed in 12 experimental units for six weeks. The experiment was conducted ...
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The aim of this study was to investigate the effects of adding betaine to diets of Ross and Arian strains that received drinking water with total concentration of TDS. 720 single-day broiler chicks, Ross and Arian strains were distributed in 12 experimental units for six weeks. The experiment was conducted in a completely randomized design with factorial arrangement (2 × 2 × 3) containing two levels of additive betaine (0 and 0.2% diet) and three levels of TDS (400, 2000 and 3500 mg / l) with four replicates and 15 chicks in Every repetition was done on the seventh day. . With the increase in TDS water content, the body weight of the chicks decreased, and the conversion factor of food and water consumption increased. Additive betaine had a significant effect on the increase in weight and water consumption during the durability period. The percent mortality and moisture content of the waste was higher in treated water with higher TDS. The amount of moisture was reduced by the addition of betaine. The effect of adding betaine and increasing TDS on the concentration of sodium chloride in chicks was significant at 28 days of age (P <0.05). By increasing TDS in drinking water, the BHMT enzyme gene expression in the liver of the chicks also decreased in the Arian strain relative to the Ross strain. The gene expression increased with the addition of betaine to the ration of chicks.
Mehdi Moosavi; M. Khodaee; Mehdi Kazemi; Mehdi poorhamdollah
Abstract
Eighty multiparous lactating dairy cows averaging days in milk 35-d were allocated in two separate experimental diet (Glucogenic vs. Lipogenic) in a changeover design. The performance, blood metabolites, liver enzymes and insulin were evaluated. The study lasted 44 days in two 22 days periods with the ...
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Eighty multiparous lactating dairy cows averaging days in milk 35-d were allocated in two separate experimental diet (Glucogenic vs. Lipogenic) in a changeover design. The performance, blood metabolites, liver enzymes and insulin were evaluated. The study lasted 44 days in two 22 days periods with the first 17 d as adaptation period and the last 5 days as sample collection period. The results show that neither dry matter intake nor milk yield were affected with treatments (P > 0.05). However, the cows received the lipogenic diet showed to have greater milk fat content, and cows received glucogenic diet showed to have greater milk protein content. Regarding the blood metabolites results show that blood glucose was tended to be greater in glucogenic diet (P = 0.08). Howevere triglyceride and blood urea concentrations were constant between two treatments. The concentrations for BHB (P = 0.04) as well as cholesterol (P= 0.05) were increased in lipogenic diet fed dairy cows. The insulin concentration was increased significantly in lipogenic diet fed cows (P = 0.02). The results show that regardless the improvement in glucose as well as BHB concentration in blood of dairy cows fed with glucogenic diet, howevere fat corrected milk as well as milk energy output were improved for lipogenic diet. In addition increased insulin and cholesterol in dairy cows fed higher fat content has potential to improve dairy cow’s fertility. In conclusion based on our results the lipogenic diet may be recommendable for dairy cows fed high RUP level.
morteza behroozlak; mohsen daneshyar; Roghaye pourbayramian; Vahid Vahedi
Abstract
This experiment was performed to evaluate the different ratios of organic and inorganic Iodine (0:100, 25:100, 50:50, 75:25, 100:0) on the performance, blood parameters and serum thyroid hormones in broiler chickens in a completely randomized design with 5 treatments were tested in 5 replicate pens. ...
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This experiment was performed to evaluate the different ratios of organic and inorganic Iodine (0:100, 25:100, 50:50, 75:25, 100:0) on the performance, blood parameters and serum thyroid hormones in broiler chickens in a completely randomized design with 5 treatments were tested in 5 replicate pens. The results showed that there was no significant difference between treatments in weight gain, feed intake and feed conversion ratio. The highest concentrations of T3, TSH and TRH were detected in 75% organic Iodine treatment (p < 0.05). The diet contained 100% organic Iodine was highest concentrations of tetraiodothyronine (T4) among treatments (p < 0.05). In blood serum, chicks fed with a diet containing 75% organic Iodine treatment were found to have the highest levels of glucose, total protein, nitrogen urea and superoxide dismutase, glutathione peroxidase enzymes (p < 0.05). However, there was no significant difference in the concentration of creatinine and uric acid blood. Generally, according to the results of this experiment, the replacement of mineral supplement with organic supplementation of iodine without negative effects, affected on blood parameters and concentration of thyroid hormones, so that the highest concentration in treatment of 75%organic iodine + 25% inorganic iodide was observed.
AhmadAli sabetan shirazi; Ahmad Hassanabadi; Mohammad Javad Agah; Hassan Nasirimoghaddam
Abstract
AbstractThis study was conducted to investigate the effect of adding olive leaf (OL) and coriander seeds (CS) powder to the diet on performance, jejunum morphology and nutrient digestibility of broiler chickens. Seven hundred and twenty Cobb 500 broilers (mixed sex) were randomly distributed to 36 experimental ...
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AbstractThis study was conducted to investigate the effect of adding olive leaf (OL) and coriander seeds (CS) powder to the diet on performance, jejunum morphology and nutrient digestibility of broiler chickens. Seven hundred and twenty Cobb 500 broilers (mixed sex) were randomly distributed to 36 experimental units and 12 dietary treatments (3 replicates with 20 birds in each). The completely randomized design with factorial arrangement 4×3 with 4 levels of OL (0, 2, 2.5 and 3 percent of diet) and 3 levels of CS (0, 0.3 and 0.6 percent of diet) were used. The results showed that the simultaneous consumption of olive leaf and coriander seeds did not have a significant effect on the performance of broilers.. Broilers that received OL with CS had significantly higher crypt depth, villus length, width and surface area than control treatments. Broilers that used OL and CS simultaneously showed higher digestibility of protein and fat. According to the results of this study, although the use of OL and CS did not have a significant effect on weight gain, feed intake and FCR, may be recommended for improvement of small intestinal morphology indices and increased digestibility of lipid and protein.
Hossein Mohebodini; amin ashayerizadeh; Vahid Jazi; Majid toghiani; akram shabani; Elham Assadi Soumeh
Abstract
In order to investigate the synergistic effects of diets containing fermented soybean meal and mannan-oligosaccharide prebiotic on growth performance and some physiological parameters of broiler chicks, an experiment was performed using 480 one- day old Ross 308 broilers in a completely randomized design ...
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In order to investigate the synergistic effects of diets containing fermented soybean meal and mannan-oligosaccharide prebiotic on growth performance and some physiological parameters of broiler chicks, an experiment was performed using 480 one- day old Ross 308 broilers in a completely randomized design with 4 treatments and 6 replicates. The experimental treatments included: 1) basal diet (based on corn and common soybean meal), 2) basal diet plus prebiotic, 3) diet containing corn and fermented soybean meal (total replacement of common soybean meal with fermented soybean meal) and 4) diet containing corn and fermented soybean meal plus prebiotic. The results of this study indicated that during the entire production period (1 to 42 days of age), birds fed diet containing fermented soybean meal plus prebiotic had higher body weight gain and better feed conversion ration than other experimental diets (p < 0.05). The increase in villus height and villus height to crypt depth ratio in duodenum and jejunum and increase in population of lactic acid producing bacteria, as well as the reduction in population of coliforms and Clostridium species in the ileum and cecum of chicks fed diets containing prebiotic, fermented soybean meal and fermented soybean meal plus prebiotic were significant when compared with control group (p < 0.05). The intestinal protease activity in birds receiving diets containing fermented soybean meal and fermented soybean meal plus prebiotic was significantly higher than those of other birds (p < 0.05).
M. Vatankhah; S. Zakizadeh
Abstract
Crossbreeding is used in order to take advantage of the different and complementary strong points of two or more breeds and to utilize hybrid vigor. In this study the results of sheep crossbreeding have been reviewed from published over the last years in Iran. The results showed that much of the crossbreeding ...
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Crossbreeding is used in order to take advantage of the different and complementary strong points of two or more breeds and to utilize hybrid vigor. In this study the results of sheep crossbreeding have been reviewed from published over the last years in Iran. The results showed that much of the crossbreeding in the sheep industry in Iran due to incorrect selection of breeds was not suitable. The main disadvantages points of Iranian sheep are low reproduction performance, low longevity, insufficient growth rate, unsuitable carcasses composition and feed efficiency, respectively. While, in the most crossbreeding schemes have been done between Iranian breeds of sheep, focused on improve growth traits and reduced fat-tail weight, which created low and no significant changes in crossbreds for these traits, leading to reducing economical efficiency and unsustainable of rearing sheep in semi-intensive or village system over last years. Sustainability could been achieved by combining desirable characteristics from the indigenous breeds to keep fitness and marketability with those of specialist exotic breeds that had already demonstrated genetic potential for traits of economical importance for commercial production. However, research findings suggested that in well-planned efforts to create composite breeds (with minimum 50% native) using the prolific breeds (such as Romanov), with high mothering ability, low maturity age, suitable carcass composition and medium ewe body weight could increased productivity of sheep in village system in Iran.
Abdolhakim Toghdory; Taghi Ghoorchi; Mohammad Asadi; Reza kamali
Abstract
In order to investigate the effect of using different levels of maize bran on microbial population, rumen and blood parameters and nitrogen retention in Dalagh ewes, 20 ewes in Third parturition with a mean weight of 36.3 ± 3.7 kg were used. This experiment was conducted in a completely randomized ...
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In order to investigate the effect of using different levels of maize bran on microbial population, rumen and blood parameters and nitrogen retention in Dalagh ewes, 20 ewes in Third parturition with a mean weight of 36.3 ± 3.7 kg were used. This experiment was conducted in a completely randomized design with four treatments and five replications. The treatments consisted of: first treatment (without maize bran), second treatment (containing 7 percent maize bran), third treatment (containing 14 percent maize bran) and fourth treatment (containing 21 percent maize bran). The results of this experiment showed that using different levels of maize bran in ewes had no significant effect on ruminal protozoan and microbial population (P >0.05). The experimental treatments did not affect ruminal pH in fasting, three and six hours after morning feeding (P>0.05). Ammonia concentration in rumen fluid in third treatment were significantly higher than other treatments (p < 0.05). There were no significant difference in blood glucose, cholesterol, triglyceride, urea, total protein, albumin and globulin levels between treatments (P >0.05), Also, there were no significant difference between treatments in nitrogen intake, urine excretion nitrogen, excretion of nitrogen in faeces and apparent restoration of nitrogen (P>0.05). In general, this study showed that there is no significant difference between treatments receiving maize bran with different levels and control treatment in terms of rumen parameters, blood parameters and nitrogen retention. In conclusion, corn bran up to 21% can be used in sheep ration without any negative effect
Sharif Khodamoradi; Farshid Fatahnia; Hoshang Jafari; Golnaz Taasoli; Y. Mohammadi
Abstract
In the present study the effect of vitamin C and copper injection in transition dairy cows on colostrum composition and serum metabolites of neonatal dairy calves was examined. Twenty multiparous (second parity, with 603.2 ± 53 kg average BW) and twenty multiparous (third and fourth parity, 669.1± ...
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In the present study the effect of vitamin C and copper injection in transition dairy cows on colostrum composition and serum metabolites of neonatal dairy calves was examined. Twenty multiparous (second parity, with 603.2 ± 53 kg average BW) and twenty multiparous (third and fourth parity, 669.1± 51 kg average BW) selected and divided to four balanced groups based on BW abd parity. Experimental treatments consisted of control (injection of 7 ml of NaCl % 0.9), Vitamin C (injection of 25 mg vitamin C solution/kg BW), Copper (injection of 75 mg copper solution/day) and Vitamin C-Copper (simultaneous injection of 25 mg vitamin C solution/ kg BW and 75 mg copper solution/day). Solutions were injected on d 20 and 40 before of expected calving. Copper injection increased red blood cells counts and serum concentration of copper (P < 0.05) compared with not injected groups. Colostrum fat, protein, lactose, solid not fat and immunoglobulin G concentrations, calf birth weight, serum concentration of vitamin C, superoxide dismutase, calcium, phosphorus and metabolites did not affected by simultaneous injections of vitamin C and copper solutions. Blood neutrophil count in calves of cows receiving simultaneous injection of vitamin C and copper solutions tended to increase (P = 0.06) compared with other groups. In general, simultaneous injection of vitamin C and copper during the dry period had no effect on colostrum composition and blood parameters in postpartum dairy cows, but may improve immunity system of their calves by increasing blood neutrophil concentration.
Ebrahim Bahreini; mohammad bojarpour; S. A. Hoseini; somaya salary; Hedayatollah Roshanfekr; Amir Hossein Alizadeh Ghamsari
Abstract
This study was conducted to determine threonine requirement of Arian 386 broiler chickens at finisher period (days 22 to 42), using performance, immunity and blood parameters responses in a completely randomized design with six levels of threonine (0.66, 0.76, 0.86, 0.96, 1.06 and 1.16%), five replicates ...
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This study was conducted to determine threonine requirement of Arian 386 broiler chickens at finisher period (days 22 to 42), using performance, immunity and blood parameters responses in a completely randomized design with six levels of threonine (0.66, 0.76, 0.86, 0.96, 1.06 and 1.16%), five replicates and 20 birds per each replicate. Requirement was determined by broken line method. Average daily feed intake was not affected by dietary level of threonine during days 22 to 42. Average daily weight gain and feed conversion ratio in broiler chickens fed the level of 0.66% threonine were respectively lower and higher compared to the other groups. The serum concentrations of glucose, cholesterol, triglyceride, calcium, phosphorus, albumin, total protein, LDL and globulin were not affected by different levels of threonine. The serum concentration of uric acid was reduced in birds received 0.96% threonine comparing the other groups and serum HDL level was increased in birds fed with 0.66 and 0.76% threonine. Number of white and red blood cells, percentage of hematocrit, heterophil, lymphocyte, heterophil to lymphocyte ratio, titer of antibody including IgG, IgM and total antibody in response to SRBC injection were not affected by different levels of threonine. Considering serum uric acid and HDL, threonine requirement during finisher period were estimated 1.058 and 0.995%, respectively. Totally, range of 0.9-1.0% can be suggested for threonine requirement of Arian 386 broiler chickens in finisher period (days 22 to 42).