Ramin Kasaeizadeh; Somayyeh Salari; Mohammad Reza Abdollahi; Farshad Baghban
Abstract
Introduction: In the past studies, the beneficial effect of insoluble fiber in broiler feed has been well demonstrated. Studies have shown that moderate amounts of fiber in poultry diets lead to significant improvements in nutrient utilization efficiency. Depending on the type of dietary fiber (soluble ...
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Introduction: In the past studies, the beneficial effect of insoluble fiber in broiler feed has been well demonstrated. Studies have shown that moderate amounts of fiber in poultry diets lead to significant improvements in nutrient utilization efficiency. Depending on the type of dietary fiber (soluble or insoluble), the particle size plays a role in the growth and development of gizzard and improves the mixture of digestive substances with digestive secretions. On the other hand, nutritionists are trying to respond to the rapid growth needs of birds by increasing the energy concentration of diets. Fats are considered for this purpose, as their energy value is at least twice that of carbohydrates and proteins. At a young age, the secretion of bile acids and the activity of pancreatic lipase are low, and therefore, the ability to digest fat in young broilers is compromised. Some studies have shown that cellulose and oat hull as a source of insoluble fiber (3%) in the diet of broiler chickens have increased the apparent digestibility of crude fat in the ileum and increased the availability of energy for the bird. Therefore, the purpose of this research is to investigate the effects of sunflower hull with different particle sizes in diets containing different sources of fat on growth performance, digestibility of nutrients and the microbial population of the caecum of broiler chickens.
Materials and methods: This experiment was conducted using 360 one-day-old Ross 308 broiler chickens in a completely randomized design with a 2×3 factorial arrangement for 42 days. Experimental treatments included: sunflower hulls (SFH) (without hulls, 3% with 1 mm particle size and 3% with 5 mm particle size) and different fat sources (3% tallow, 3% canola oil). Feed intake (FI) and body weight gain (BWG) of birds were recorded and feed conversion ratio (FCR) was calculated. To determine the ileal digestibility of nutrients, 3 g/kg of chromium oxide was fed to chickens on days 37-42 of the rearing period. On the 42nd day of rearing, the ileum contents of 2 birds were collected and stored in a freezer at -20◦C. To investigate the morphology of the small intestine, 5 cm of the duodenum, jejunum and ileum were taken. Cecal microbial population also determined at 42 days of age. The data obtained from the experiment were analyzed using SAS statistical software and GLM procedure. To compare means, Duncan's (1955) multi-range test was used at a significant level of 5%.
Results and discussion: The results showed that, using of the coarse and fine SFH in the diet of broiler chickens increased FI and improved the FCR in the whole period of experiment (P<0.05). Canola oil improved FI and BWG compared to tallow (P<0.05). Apparent digestibility of crude protein and crude fat also increased by using of coarse SFH in the diet (P<0.05). The use of coarse SFH increased the villus height of duodenum and the villus height and thickness of ileum (P<0.05). Canola oil increased the villus height of ileum, but decreased the villus thickness compared to tallow treatment (P<0.05). The use of coarse SFH in the diet reduced the population of Escherichia coli bacteria in the cecum, and coarse SFH with different sources of fat increased the population of Lactobacillus (P<0.05).
Conclusions: In general, the results of the present study showed that the addition of coarse sunflower hull to the diet could improve the growth performance of broilers by increasing the digestibility of crude protein, crude fat, Lactobacillus population, and reducing the cecal population of E. coli. Although its interaction with canola oil also had positive effects on the population of beneficial gut bacteria.
Zahra Kordpour; Somayyeh Salari
Abstract
In order to investigate the effects of using live, autolyzed yeast and their combination on performance, and intestinal histology in Japanese quail, 360 of one-day-old chicks were used. Birds were randomly divided into 4 experimental groups in a completely randomized design with 6 replicates. The experimental ...
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In order to investigate the effects of using live, autolyzed yeast and their combination on performance, and intestinal histology in Japanese quail, 360 of one-day-old chicks were used. Birds were randomly divided into 4 experimental groups in a completely randomized design with 6 replicates. The experimental groups included the control group: fed with basal diet without additives, the second group: fed with basal diet containing 0.4% live yeast, the third group: fed with basal diet containing 0.4% autolyzed yeast and the fourth group: fed with basal diet containing 0.2% live yeast and 0.2% autolyzed yeast. The results showed that the addition of autolyzed yeast caused the greatest increase in body weight gain compared to the control and their mixture in the whole period of experiment (P<0.05). The weight of thigh and pancreas as well as the length of duodenum increased significantly in birds fed with autolyzed yeast compared to live yeast and their mixture (P<0.05). The highest height of duodenal villi was observed in birds fed with autolyzed yeast and live yeast compared to the control treatment and their mixture. Birds fed with autolyzed yeast showed a significant decrease in E. coli bacteria and an increase in Lactobacillus bacteria (P<0.05). The results showed that the use of autolyzed yeast as well as live yeast can be useful in feeding Japanese quails due to improving performance, increasing the height of duodenal villi, reducing the microbial population of E. coli and increasing the cecal population of Lactobacillus.
Leili Abdali; Somayyeh Salari; Mohammad Reza Ghorbani; Shima Hossini Far
Abstract
An experiment was conducted to determine the effects of autolyzed yeast with enzyme supplementation and barley particle size on energy and protein efficiency ratio, immune system and ileal digestibility with 400 one-day-old Ross 308 broiler chickens from both sexes in completely randomized design with ...
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An experiment was conducted to determine the effects of autolyzed yeast with enzyme supplementation and barley particle size on energy and protein efficiency ratio, immune system and ileal digestibility with 400 one-day-old Ross 308 broiler chickens from both sexes in completely randomized design with factorial arrangement 2×4 with 8 treatments, 5 replicates from 1 to 35 days of age. The experimental treatments included type of additive (without additive, enzyme, autolyzed yeast and autolyzed yeast with enzyme) and barley particle size (fine (2 mm) and coarse (8 mm)). Supplementation of autolyzed yeast and enzyme improved FCR compared to the treatment without additives (P>0.05). Autolyzed yeast with coarse barley particles increased the European efficiency factor, energy and protein efficiency ratio compared to other treatments (P>0.05). Supplementation of enzyme led to a decrease in abdominal fat percentage compared to other treatments (P<0.05). Autolyzed yeast with enzyme increased the length and dry matter percentage of the tibia compared to the treatment without additives (P<0.05). Addition of autolyzed yeast with enzyme improved the response immune system compared to other treatments (P<0.05). Supplementation of autolyzed yeast with enzyme improved the ileal digestibility compared to other treatments (P<0.05). Addition autolyzed yeast alone and with enzyme decreased litter pH compared to the treatment receiving enzyme alone and the treatment without additive (P<0.05). As summary, autolyzed yeast with enzyme can be used to improve the performance of broiler chickens fed diets containing barley.
Seyyed Majid Azarm; Somayyeh Salari; Mohsen Sari; Mohammad Reza Ghorbani; Mohammad Hojjati
Abstract
This experiment was conducted to evaluate the effect of Thyme essential oil on performance and some physiological parameters of broiler chickens fed diets containing wheat in a completely randomized design with a 2×3 factorial arrangement using 264 broilers (Ross 308) in ground floor. Treatments ...
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This experiment was conducted to evaluate the effect of Thyme essential oil on performance and some physiological parameters of broiler chickens fed diets containing wheat in a completely randomized design with a 2×3 factorial arrangement using 264 broilers (Ross 308) in ground floor. Treatments consisted of 2 levels of wheat (0 and 50% of the diet) and 3 levels of essential oil of Thyme (0, 200 and 400 ppm). Performance parameters were recorded weekly. Determination of micro-flora, carcass characteristics, and blood parameters were done on day 42. The results showed that adding the Thyme essential oil to the diet containing 50% wheat increased feed intake at the all period of experiment. Body weight gain was increased significantly in the birds that consumed 50% wheat with 400 ppm essence compared to the birds consumed the diet without wheat or without essence at the starter period. The birds consumed the diet without wheat with essence had lower blood concentration of LDL. Although, adding essence at the level of 400 ppm to the diet without wheat increased significantly blood concentration of HDL. The diet contained 50% wheat without essence had higher abdominal fat compared to the diet with 200 and 400 ppm of essence without wheat and also the diet contained 50% wheat with 400 ppm essence. Overall, the use of Thyme essence at the level of 400 ppm in wheat-based diet is recommended for increasing feed intake and improving some physiological parameters of broiler chickens.
Mohammad Reza Nehirat; Somayyeh Salari; Mohammad Reza Ghorbani
Abstract
In order to compare the effect of prebiotic and various types of fibers on performance and some physiological parameters of broiler chickens, an experiment was performed with 320 chicks with eight treatments in a completely randomized design. Dietary treatments were basal diet (corn-soybean meal), basal ...
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In order to compare the effect of prebiotic and various types of fibers on performance and some physiological parameters of broiler chickens, an experiment was performed with 320 chicks with eight treatments in a completely randomized design. Dietary treatments were basal diet (corn-soybean meal), basal diet with prebiotic (Biolex, MB40), and various sources of fiber (wheat bran (WB), soybean hull (SH), and palm kernel meal (PKM)). Different types of fiber and prebiotics were added to the diet at 1.5,3% and 2 g/kg, respectively. The birds that consumed 1.5% of PKM had the best feed conversion ratio compared to the other treatments except 3% of PKM and control diet (P<0.05). Abdominal fat pad significantly decreased in birds that consumed various types of fiber compared to the control diet (P<0.05). Apparent ileal digestibility of organic matter and crude protein increased in birds that consumed 3% palm kernel meal (P<0.05). The apparent ileal digestibility of ether extract decreased in birds that consumed PKM compared to the control diet (P<0.05). Dietary inclusion of various types of fiber caused a significant decrease in plasma cholesterol and triglycerides compared to the control diet (P<0.05). The results showed that dietary inclusion of PKM improved performance, decreased abdominal fat pad and E.coli and coliform population of cecum and increased digestability of crude protein and population of Lactobacillus of cecum in broiler chickens.
mohammad Bojarpour; Akbar Yaghoobfar; somayeh salari
Abstract
This experiment was conducted to evaluate the effects of physical form, barley variety and enzyme addition on Ileal digestibility, apparent metabolizable energy (AME) and energy efficiency of broiler chickens.The experiment was carried using a factorial experiment with a completely randomized desiegn. ...
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This experiment was conducted to evaluate the effects of physical form, barley variety and enzyme addition on Ileal digestibility, apparent metabolizable energy (AME) and energy efficiency of broiler chickens.The experiment was carried using a factorial experiment with a completely randomized desiegn. Factors were barley varity (Fajr, Reyhaneh, and Yosef), diet form (mash or pellet) and enzyme level (0 and 0/05 g/kg dry matter). Here 927 one day-old Ross 308 broiler chickens were assigned to 12 treatments, 3 replicates and 27 chickens in each replicate. The results of experiment indicated that the digestibility of nutrients, AME, apparent metabolizable energy corrected to zero nitrogen retention (AMEn) and energy efficiencies (NE/AMEn) affected by barley variety (p <0/05). Net Energy (NE) affected by main and interaction effects (P < 005). Diets containing Ryhaneh barley variety in comparison with other varietys, increased Ileal Digestibel Protein (IDP), Ileal Digestibel fat (IDF), NE, AME and AMEn (P <0/05). Although pelleting decreased Ileal Digestibility of nutrients (p>005), NE, AME and AMEn (p <0/05), addition of enzyme to diet increased this indicators (P <0/050). According to these results, the use of pellet diet containing Ryhaneh variety with enzyme improved digestibility and energy efficiency and thus it's recommended to be used in poultry nutrition.
babak masouri; somayeh sallary; heshmatollah khosravinia; saleh tabatabaei vakili; tahereh mohammadabadi
Abstract
This study was carried out to examine the effect of supplementation of canola and fish oils (5% fish oil, 3% fish oil + 2% canola oil, 2% fish oil + 3% canola oil and 5% canola oil) and Satureja khuzistanica essential oils (SkEO) (0 and 400 mg/kg), into a basal diet on productive performance, meat cholesterol, ...
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This study was carried out to examine the effect of supplementation of canola and fish oils (5% fish oil, 3% fish oil + 2% canola oil, 2% fish oil + 3% canola oil and 5% canola oil) and Satureja khuzistanica essential oils (SkEO) (0 and 400 mg/kg), into a basal diet on productive performance, meat cholesterol, lipid stability and certain blood lipid components in broiler chickens raised under normal and heat stress conditions during day 22 to 42 of age. The experiment was conducted in a 4×2×2 factorial expriment using 640 one-day-old Ross 308 chicks in a completely randomised blocks design with 5 replicates of 8 birds in each replication. Oil source significantly decreased FCR, serum LDL and cholesterol content in thigh and breast muscles at day 42 of age. Inclusion of 400 mg/kg SkEO in diet significantly increased daily weight gain and decreased cholesterol content and TBARS concentration in thigh and breast muscles in heat stressed chicks. Heat stress condition significantly decreased FCR and increased TBARS as well as cholesterol content in breast muscle and serum cholesterol concentration during day 22 to 42 of age. It was concluded that supplementation of 400 mg/kg SkEO and canola oil into diet could have a positive effect on productive performance and reduce the meat and serum cholesterol concentration in broiler chicken.
Abbas Rajaei Rad; Mohsen Sari; Mohammad javad Zamiri; Morteza Chaji; Somayeh Salari
Abstract
Palm date leaves were processed with lime in a processing reactor in a factorial arrangement of treatments (3 × 3) with 3 levels of temperatures (40, 80 and 100°C) and time periods (80, 160, and 240 minutes) in a completely randomized design. Fermentation parameters measured using gas production ...
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Palm date leaves were processed with lime in a processing reactor in a factorial arrangement of treatments (3 × 3) with 3 levels of temperatures (40, 80 and 100°C) and time periods (80, 160, and 240 minutes) in a completely randomized design. Fermentation parameters measured using gas production technique. With increasing pretreatment time and temperature lignin content reduced from 13.0 percent in untreated leaves to 6.0 percent in leaves treated in 100°C for 240 min. Increasing time and temperature of the processing decreased ash content (P<0.01). Calcium concentration was increased from 0.58 percent in untreated leaves to 0.94 in the processed biomass at a temperature of 40°C for 80 min (P<0.01). Interaction was significant among pretreatment time and temperature on cell wall, dry matter loss, gas production from fermentable fraction and gas production (P<0.01). Gas production at the end of 72 h incubation increased from 76.2 ml per gram of dry matter in untreated samples to 189.8 ml per gram of dry matter in the treatment of 100°C for 240 min. Organic matter digestibility increased with increasing severity of pretreatment from 26.5 percent in the treatment of 40°C for 80 min to 36.4 percent in the treatment of 100°C for 240 min. The images of scanning electron microscopy showed more pores and holes in pretreated samples with increasing temperature and processing time compared to untreated sample. Results indicated that lime pretreatment with heat can remove lignin and improve in vitro digestibility of date leaves.
D Shafieipour fard1; Somayeh Salari; Mohsen Sari; Saman Abdanan Mehdizadeh; Mehdi Zarei
Abstract
This experiment was conducted to evaluate the effect of different lipid sources and organic zinc supplementation on performance, egg bacterial activity and ovary morphology of laying hens for 10 weeks. with 288 sixty weeks old birds by employing a completely randomized design with factorial arrangement ...
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This experiment was conducted to evaluate the effect of different lipid sources and organic zinc supplementation on performance, egg bacterial activity and ovary morphology of laying hens for 10 weeks. with 288 sixty weeks old birds by employing a completely randomized design with factorial arrangement of 3×4 with 12 treatments, 4 replicates and 6 hens each. The factors of interest were 4% lipid from different sources (soybean oil, fish oil and tallow) and various levels of zinc (40, 100, 200 and 300 mg/kg of diet). In all three lipid sources, significant reduction (P<0.05) was observed in feed intake when the level of zinc supplementation increased. Haugh unit was significantly (P<0.05) increased in diets containing different lipid sources as the level of zinc supplementation increased. The highest Haugh unit value was observed at the level of 100 mg/kg of zinc supplementation with soybean oil and fish oil. Increasing levels of zinc supplementation significantly (P<0.05) improved eggshell thichness, eggshell strength and eggshell percentage. The number of large white follicles linearly increased in diets containing tallow, when the level of zinc supplementation increased. The egg yolk microbial load was significantly (P<0.05) decreased by different lipid sources as the level of zinc supplementation increased. According to the results, it seems that the addition of zinc to the diets containing different lipid sources could not affected performance parameters but decreased egg yolk microbial load.
Zeinab Moradpour; Somayeh Salari; Mohammad Reza Ghorbani; Mohsen Sari
Abstract
This experiment conducted to evaluate the effect of different methods of force molting on performance, egg quality of laying hens with one hundred eighty of 52-wk old Hy-line layer in completely randomized design with six treatments, five replicates for 90 days. Treatments include 1 - feed withdrawal ...
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This experiment conducted to evaluate the effect of different methods of force molting on performance, egg quality of laying hens with one hundred eighty of 52-wk old Hy-line layer in completely randomized design with six treatments, five replicates for 90 days. Treatments include 1 - feed withdrawal (FW), 2 - 50 percent alfalfa meal: 50 percent layer ration, 3 - 75 percent alfalfa meal: 25 percent layer ration, 4 - 100 percent alfalfa meal, 5 - whole barley grain (WBG) and 6 - high level of zinc oxide (20000 ppm) that were used for 10 days. The highest percentage of weight loss was observed in FW and zinc oxide groups (P<0.05). Egg production of birds that fed 50 percent alfalfa meal: 50 percent layer ration stopped later and reached to 50 percent egg production sooner than the other treatments (P<0/05). The WBG and 100 percent alfalfa meal had better egg production feed conversion ratio in compare to FW birds (P<0.05). The mean egg weight observed higher in FW group and egg yolk color was higher in FW and WBG groups in compare to the other treatments (P<0.05). The WBG and zinc oxide groups had highest eggshell percentage (P<0.05). According to the results of this experiment it seems that WBG and 100 percent alfalfa meal groups are the useful methods for force molting because of improving performance parameters of layers.
Mohammad Reza Jamali; Mohammad Reza Ghorbami; Ahmad Tatar; Somayyeh Salari; Morteza Chaji
Abstract
Two experiments were conducted to evaluate the nutritional value of Purslane powder and its effects on performance, egg quality and reproductive system parameters of laying hens. One hundred and twenty laying hens (Leghorn, Hy-Line W-36) were used in a completely randomized design with four treatments ...
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Two experiments were conducted to evaluate the nutritional value of Purslane powder and its effects on performance, egg quality and reproductive system parameters of laying hens. One hundred and twenty laying hens (Leghorn, Hy-Line W-36) were used in a completely randomized design with four treatments and five replicates. Hens received diet supplemented with different levels of Purslane powder (0, 1, 2 and 3 percent) for 8 weeks. The results of these expriments showed that gross energy, crude protein, ether extract and crude fiber contents of Purslane samples were 2921.67 (Kcal/Kg DM), 22.28 (percent), 3.99 (percent) and 9.47 (percent) of DM, respectively. The AME and TME values of Purslane powder were 1864.70 and 1956.08 Kcal/Kg DM, respectively. Performance parameters of the laying hens were not affected by inclusion different levels of dietary Purslane powder in the diet. Shell strength, shell thickness, egg yolk color, ovary and oviduct weights, the number of large yellow follicles and the weight of largest follicle showed significant increase (P< 0.05) in treatments containing Purslane as compared to control group. According results of this experiment, use of Purslane powder in laying hens diet can improve quantitative traits of eggs and reproductive parameters. Therefore, Purslane powder can be used in the diets of laying hens at three percent.
Elahe Rezaei; Saleh Tabatabaei Vakili; Khalil Mirzadeh; Somayeh Sallary; Mehdi Zarei
Abstract
This study was carried out to evaluate the effect of different levels of anise seed on the performance, immune system, antioxidant activity and blood estrogen level of broiler chicks. A total of 192 day -old Ross 308 broilers were trained for 42 days in a completely randomized design with four treatments, ...
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This study was carried out to evaluate the effect of different levels of anise seed on the performance, immune system, antioxidant activity and blood estrogen level of broiler chicks. A total of 192 day -old Ross 308 broilers were trained for 42 days in a completely randomized design with four treatments, four replicates and 12 birds per each replicate. Treatments were included the levels of zero (control(, 0.3, 0.6 and 0.9 percent of anise seed in diet. SRBC was injected at day 28 and blood samples were collected from chickens at days 35 and 42 of rearing. Dietary anise supplementation had no positive effect on feed intake and weight gain of broilers. In starter period, the chicks fed by 0.3 percent of anise seed, had the least feed conversion ratio (P<0.05). However, anise seed levels had no positive effects on feed conversion ratio in grower and total rearing period. Anise seed caused the higher antibody titer against SRBC in day 35 of rearing (P<0.05). The cellular immunity did not improve by anise seed levels in broilers. The 0.3 percent of anise seed, caused the higher total antioxidant capacity of blood plasma than control chicks (P<0.05). The blood serum estrogen level was reduced in 0.3 and 0.6 percent, but increased in 0.9 percent of anise seed (P<0.05). Generally, however the anise seed dose not improves performance traits and cellular immunity of broilers, but increse the primary humeral immunity and total antioxidant capacity of chicken.
Parvin Saeedi; Saleh Tabatabaei; Somayeh Sallary; Khalil Mirzadeh; Mehdi Zarei
Abstract
In order to evaluation the effect of Nigella Sativa supplementation on performance, immune response and some of blood parameters, a total of 192 one day old Ross 308 broilers were used in a completely randomize design with four treatments, four replicates and 12 observations in each replicate. Treatments ...
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In order to evaluation the effect of Nigella Sativa supplementation on performance, immune response and some of blood parameters, a total of 192 one day old Ross 308 broilers were used in a completely randomize design with four treatments, four replicates and 12 observations in each replicate. Treatments included the increasing levels of zero (control), 0.4, 0.8 and 1.2 percent Nigella sativa. In grower and whole period of experiment, the weight of birds received 0.4 and 0.8 percent of Nigella sativa was higher than control group birds (P<0.05). The supplementation of Nigella sativa in diet has not effect on feed intake and feed conversion ratio in starter, grower and total rearing periods. The weights of bursa and thymus in birds received 0.4 and 0.8 percent of Nigella sativa werehigher than control group birds (P<0.05). The weight of liver in birds belong to 0.4 percent of Nigella sativawas higher than control group (P<0.05). Addition of Nigella sativa in dietreduced the glucose, triglyceride, cholesterol, LDL and increased the HDL in blood serum. The use of Nigella sativa in dietary of birds caused the higher total white blood cells and lower heterophil: lymphocyte ratio. The birds which received 0.4 and 0.8 percent of Nigella sativa had the higher total antioxidant capacity than control group in blood plasma. In conclusion, the use of Nigella sativa up to 0.8 percent in diet, in addition to improvement the performance, increased the immune system activity and total antioxidant capacity in Ross 308 broiler chickens.
Morteza Nadali; Somayyeh Salari; Mohammad Boujarpour; Saleh Tabatabaei Vakili; Mohsen Sari
Abstract
Effect of levels of zinc supplementation on footpad lesions, reproductive and blood parameters of broiler breeders with 300 hens and 40 roosters of Ross 308 strain with four treatments, five replicates and 15 hens and two roosters in each for 12 weeks was evaluated in a completely randomized design. ...
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Effect of levels of zinc supplementation on footpad lesions, reproductive and blood parameters of broiler breeders with 300 hens and 40 roosters of Ross 308 strain with four treatments, five replicates and 15 hens and two roosters in each for 12 weeks was evaluated in a completely randomized design. Dietary treatments were 80, 110, 140 and 170 mg zinc/kg diet. Increasing supplemental zinc level especial 170 mg/kg diet increased hatchability (P<0.05). Levels of 140 and 170 mg zinc/kg diet significantly improved footpad lesions (P<0.05). In the first phase of incubation, the lowest rate of mortality observed in 140mg zinc/kg diet (P<0.05). Also, number of large and small size follicles of broiler breeders increased at 170 mg zinc/kg diet (P<0.05). Blood parameters did not affect significantly. The results of this experiment showed that supplementation of broiler breeders diet with zinc at 140 and 170 mg/kg diet could improve hatchability and had desirable effect on footpad health.
Rohollah Ebrahimi; Tahereh Mohammadabadi; Mohsen Sari; Somayeh Sallari; Mohammadjavad Zamiri; Mohammadtaghi Beigi Nassiri
Abstract
In order to investigate the effect of different levels of silymarin (0, 100 and 200 mg/kg diet) onperformance, carcass characteristics, blood parameters and antioxidant status, 120 day-old chicks wereassigned to 3 treatments with four replicates and 10 birds in each in a completely randomized design.Results ...
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In order to investigate the effect of different levels of silymarin (0, 100 and 200 mg/kg diet) onperformance, carcass characteristics, blood parameters and antioxidant status, 120 day-old chicks wereassigned to 3 treatments with four replicates and 10 birds in each in a completely randomized design.Results showed supplementation of 200 mg silymarin significantly decreased the body weight gain(BWG) in starter (P<0.05) and whole period of experiment (P<0.01) and significantly increased feedconversion ratio at starter (P<0.05), grower (P<0.05) and total rearing periods (P<0.01). Also, addition of100 mg silymarin significantly increased the carcass relative weight (P<0.01) and supplementation of 200mg silymarin significantly increased the breast relative weight (P<0.05). Furthermore, 200 mg silymarinsignificantly increased the malondialdehyde and heterophil/ lymphocyte ratio and significantly decreasedsuperoxide dismutase (P<0.05). These results showed that supplementation of silymarin in diet undernormal condition, improved the carcass and breast relative weight, but no had effect on bird’s oxidativestatus.