mohammad asadi; Taghi Ghoorchi; Abdolhakim Toghdory
Volume 26, Issue 1 , March 2024, , Pages 33-44
Abstract
Introduction: During pregnancy, especially the period around birth, animals make many metabolic adjustments to support the transition from pregnancy to lactation. Since the last two months of pregnancy (late pregnancy) constitute 75% of fetal growth, therefore, enriching the sheep diet can have positive ...
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Introduction: During pregnancy, especially the period around birth, animals make many metabolic adjustments to support the transition from pregnancy to lactation. Since the last two months of pregnancy (late pregnancy) constitute 75% of fetal growth, therefore, enriching the sheep diet can have positive consequences on the health and general performance of the ewe and lamb. In such conditions, using of management and nutritional strategies will reduce the problems during the transition period and heat stress condition. Under stress condition, the mobilization of glycogen reserves and glucose production occur to produce energy to maintain stability in the body. Chromium is one of the scarce essential minerals that plays an important role in the metabolism of carbohydrates, lipids, proteins and nucleic acids. Chromium is part of the glucose tolerance factor that increases the affinity of insulin receptors to insulin hormone and increases the sensitivity of receptors to insulin.
Material and Methods: This experiment was conducted to evaluate the effect of different forms of chromium in ewes during the transition period under the heat stress condition. Forty pregnant Afshari ewes from 42±5 days before the expected lambing were assigned to four treatments with 10 replications in a completely randomized design. Experimental treatments included: 1) basal diet without chromium supplementation (control), 2) basal diet containing three milligrams of inorganic chromium per kg of DM, 3) basal diet containing three milligrams of chromium in the form of chromium-methionine per kg of DM and 4) basal diet containing three milligrams of chromium in the form of chromium nanoparticles per kg of DM.
Results and Discussion: The results showed that ewes receiving chromium had less weight changes at two, four and six weeks after lambing (P≥0.05). Also, supplementation of different forms of chromium increased the body condition score of ewes at the time and six weeks after lambing (P≥0.05). Ewes receiving chromium-methionine and chromium nanoparticles had better body condition than control and inorganic chromium treatments. There was no significant difference in glucose concentration between the treatments 60 and 90 minutes after intravenous glucose injection. After 60, 90, 120 and 180 minutes after the intravenous injection of glucose, the insulin concentration of the ewes receiving different forms of chromium decreased compared to the control treatment (P≥0.05).
Conclusion: In general, the use of chromium, especially in the form of chromium-methionine and chromium nanoparticles, is recommended during the transition period of ewes under the influence of heat stress.
Tayebeh Omidvar; Saied Mohammadzadeh; mosayeb amiri
Volume 24, Issue 2 , July 2022, , Pages 237-246
Abstract
To investigate the effect of rosemary powder on semen parameters and DNA fragmentation under heat stress, 40 native rooster aged 42 weeksand weighted of 2300 gramswere usedin a factorial experiment in randomized complete block design with two levels of temperature (normal and heat stress) and rosemary ...
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To investigate the effect of rosemary powder on semen parameters and DNA fragmentation under heat stress, 40 native rooster aged 42 weeksand weighted of 2300 gramswere usedin a factorial experiment in randomized complete block design with two levels of temperature (normal and heat stress) and rosemary powder (0 and 7.5 gr/kg of diet) during 7 weeks. Heat stress and normal temperature was set 28±2ºC and 18-22º C,respectively.After two weeks adaptation,the semen sampleswere collected twice in a week from roosters during 5 weeks using dorso-abdominal massage method. The semen parameters including motility, viability ratio and DNA fragmentation were evaluated. The results showed that heat stress significantly reduced the progressive motility of sperm (type A) and with the addition of rosemary powder, sperm viability increased (P˂0.05). Addition of rosemary leaf powder at normal temperature decreased the DNA fragmentation ratio (P˂0.05). In roosters under heat stress,the DNA fragmentation rate of sperm increased and the damage rate decreased significantly with the feeding of rosemary powder (P˂0.01). According to the results of this study, adding rosemary powder to the diet of native old roosters under heat stress conditions can improve some reproductive traits
Somayeh Jalalinia; Farhang Fatehi; Mehdi Dehghan banadaky; Hossein Rokhforoz
Volume 24, Issue 1 , April 2022, , Pages 23-33
Abstract
To investigate the interaction effects between season and dietary forage particle size on milk yield and composition, one hundred early lactating Holstein were allocated. Dietary forage particle size included long (7.7 mm) and fine (4.4 mm), were adjusted as an experimental treatment per season. The ...
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To investigate the interaction effects between season and dietary forage particle size on milk yield and composition, one hundred early lactating Holstein were allocated. Dietary forage particle size included long (7.7 mm) and fine (4.4 mm), were adjusted as an experimental treatment per season. The results showed that raw milk yield, protein, lactose and total solid percentage of milk were higher within spring compared to summer (p< 0.01). Milk yield and milk lactose percentage for cows fed fine forage particle size trended to be higher than cows fed long forage particle size. Also, the amount of dry matter consumed within two hours after feeding for summer was higher than spring. Totally results revealed that cows fed with fine forage particle size had more homogeneous feeding behavior pattern within both studied season than cows fed long forage particle size.
Farzad Bastami; Ali Khatibjoo; Saifali Varmaghany
Volume 24, Issue 1 , April 2022, , Pages 67-80
Abstract
The effects of valine supplementation on performance, immunity and behavoural indices of broiler chickens reared under heat stress condition was evaluated. Total of 420 male and female Ross-308 broiler chickens were allocated to 6 treatments with 5 replicates in a completely randomized design. Experimental ...
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The effects of valine supplementation on performance, immunity and behavoural indices of broiler chickens reared under heat stress condition was evaluated. Total of 420 male and female Ross-308 broiler chickens were allocated to 6 treatments with 5 replicates in a completely randomized design. Experimental groups were as fallows: positive control (fed basal diet and reared under Ross-308 recommended rearing temperature), Nagative control (fed basal diet and reared under heat stress (HS)), and four treatment groups fed basal diet supplemented with 5, 10, 15 and 20 percent valine above the Ross-308 valine recommendation and reared under HS. Heat stress significantly decreased feed intake, body weight and European production efficiency factor (EPEF), antibody titer against NewCastle, lymphocyte percentage, serum total protein concentration and alkaline phosphatase and lactate dehydrogenase activities and increased heterophile percentage, heterophile to lymphocyte ratio, rectal temperature and tunic immobility of broiler chickens (P < 0.05), but 5% valine supplementation improved BW of broiler chicken at the end of grower and BW and EPEF at the end of total period; 10% valine supplementation increased relative weight of breast and thigh muscle and 15 and 20% valine supplementation increased lymphocyte and decreased heterophile percentage as compared to control group (P < 0.05). In conclusion, 5% valine supplementation improved final body weight and feed convertion ratio of heat-stressed broiler chikens and 15 and 20% valin inclusion improved blood immune cell percentages but had no effect on humoral immune response and tunic immobility test of HS broiler chickens.
Seyed Hamed Mousavi Alamdardehi; Zarbakht Ansari Pirsaraei; Essa Dirandeh; Mohammad Kazemi Fard
Volume 23, Issue 4 , January 2022, , Pages 525-533
Abstract
Effect of Basil powder and extract on yield and carcass characteristics, relative expression of heat shock protein gene (HSP70) and some blood parameters of broiler chickens under heat stress using 160 Ross 308 one-day-old broiler chicks in a completely randomized design with 5 treatments and 4 replications ...
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Effect of Basil powder and extract on yield and carcass characteristics, relative expression of heat shock protein gene (HSP70) and some blood parameters of broiler chickens under heat stress using 160 Ross 308 one-day-old broiler chicks in a completely randomized design with 5 treatments and 4 replications (8 chickens per replication), was evaluated for 42 days. Treatments included: 1- Basic diet (control), 2- Basic diet+ Vitamin C (250 mg per kg of grain), 3- Basic diet + 25 mg of Basil powder (per kg of grain), 4- Basic diet +50 mg of Basil powder (per kg of grain), 5- The use of Basil extract (1 ml/liter water). Feed intake, body weight gain, feed conversion ratio, carcass characteristics, blood parameters and relative expression of HSP70 gene in blood were measured. The effects of treatments on blood parameters and carcass characteristics were not significant. Relative expression of the HSP70 gene in the blood was significantly reduced in all treatments compared to the control (P<0.05). Based on the results, basil powder and extract reduce the negative effects of heat stress in broilers, so their use in broiler diets is recommended to prevent heat stress.
Amin Rahimi; Farhang Fatehi; Abolfazl Zali
Volume 23, Issue 3 , September 2021, , Pages 375-385
Abstract
The current study was conducted to investigate the effect of dietary supplementing of condensed molasses soluble (Vinasse) in heat stressed mid-lactating Holstein cows on milk yield and composition, apparent nutrient digestibility and economical parameters. The experiment was performed by 84 Holstein ...
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The current study was conducted to investigate the effect of dietary supplementing of condensed molasses soluble (Vinasse) in heat stressed mid-lactating Holstein cows on milk yield and composition, apparent nutrient digestibility and economical parameters. The experiment was performed by 84 Holstein lactating dairy cows (DIM: 155±25; MY: 32±3) in a completely randomized design with three treatments 1) basal diet without vinous (control), 2) diet containing 5% of vinasse (2.2 kg/head/day) and 3) diet containing 10% 0f vinasse (4.4 kg/head/day). The study was conducted in the summer season with a temperature -humidity index of 75.1. The experiment lasted for 25 days (15 days for adaptation and 10 days for sampling). Dry matter intake of the treatment fed a 10% vinasse supplemented diet was higher than the other treatments (P<0.05). Dry matter and NDF digestibility coefficients were increased by increasing the level of vinasse in the diets, compared to the control (P<0.05). The economical index of income over feed cost was the highest for the diet containing 5% of vinasse. Totally, regarding to the chemical composition of the vinasse and its beneficial impacts on the performance of the cows under heat stress, using 5% of dry matter vinasse supplementation (2.2 kg wet weight/day or 1.1 kg dry matter/day) can improve nutrient digestibility and reduce feed costs without any adverse effects on dry matter intake.
Mohammad Reza Rezvani; Fatemeh Ahmadi
Volume 23, Issue 2 , July 2021, , Pages 235-244
Abstract
Effect of red pepper in comparison to commercial growth promoters, Biostrong and Oleobiotec, on growth performance, nutrient digestibility, and other traits of broilers under heat stress conditions using 200 day-old broiler chickens mixed male and female of Arbor Acers strain in a completely randomized ...
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Effect of red pepper in comparison to commercial growth promoters, Biostrong and Oleobiotec, on growth performance, nutrient digestibility, and other traits of broilers under heat stress conditions using 200 day-old broiler chickens mixed male and female of Arbor Acers strain in a completely randomized design with four treatments, five replications and ten chickens per replicate were evaluated. Treatments included a basal diet without additives and a basal diet containing 10, 0.1, 0.15 g/kg red pepper, Biostrong, and Oleobiotec, respectively. At the beginning of third week, the birds were exposed to heat stress for six hours per day. During the 42 days of the experiment, the mean minimum and maximum temperatures were 25°C and 33°C. Feed intake, weight gain, feed conversion ratio, the weight of internal organs, caecal microflora, and precaecal nutrient digestibility were measured for the heat stress period. The use of red pepper improved the feed conversion ratio and daily weight gain in grower and finisher periods and increased protein, lipid, and dry matter precaecal digestibility, the relative weight of bursa of Fabricius, spleen, and gizzard, and decreased the Ecoli population in caecum compared to the control treatment (P≤0.05). Biostrong and Oleobiotec did not affect growth performance, prececal nutrient digestibility, and the E.coli population. Overall, using the red pepper in the diet of broilers compared to commercial growth promoters reduced the adverse effects of heat stress on growth performance, nutrient digestibility, and caecal microflora.
Vahid Vahedi; Babak Naderi; Ciyamak Ghazaie; Azadeh Boustan
Volume 23, Issue 2 , July 2021, , Pages 303-312
Abstract
The aim of this study was the comparison of two protocols of estrus synchronization in two natural climates and heat stress condition on reproductive performance and concentration of plasma estrogen and progesterone hormones in Holstein dairy cows. One hundred and ten multiparous Holstein dairy cows ...
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The aim of this study was the comparison of two protocols of estrus synchronization in two natural climates and heat stress condition on reproductive performance and concentration of plasma estrogen and progesterone hormones in Holstein dairy cows. One hundred and ten multiparous Holstein dairy cows (28 kg average daily milk yield and parity one to four calved) were randomly assigned to two protocol groups: 1) Double-Ovsynch (DO; n=60), the cows received GnRH-7d-PGF2α-2d-GnRH and Ovsynch (GnRH-7d- PGF2α-56h-GnRH-16h-AI) was initiated 7 d later; 2) Presynch-Ovsynch (PO; n=50), the cows received PGF2α-14d-PGF2α and Ovsynch was initiated 12 d later. The both of the protocols were done in two seasons of summer and winter. The calving rate in cows that were synchronized at winter season was greater than cows synchronized in summer (36.4 vs 18.2%; P= 0.04). Mean of the number of insemination to conception was lower in cows that synchronized in winter compared to cows synchronized in summer (1.46 vs 1.74; P= 0.02). Mean of measured estrogen and progesterone hormones concentrations was higher in cows that synchronized in winter compared to summer (P < 0.05). Overall, mean of reproductive traits and hormones concentration is higher in cows that synchronized in winter than in summer and the protocol of estrus synchronization had no effect on reproductive performance.
Michael Gholipour; Vahid Vahedi; Zarbakht Ansari Pirsarei
Volume 22, Issue 3 , September 2020, , Pages 431-440
Abstract
This study was conducted to determine the effects of Propolis on growth performance, carcass characteristics and some blood parameters in broiler chickens in response to heat stress condition. A total of 160 one day-old male broiler chicks (Ross 308) were randomly divided into four treatment groups in ...
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This study was conducted to determine the effects of Propolis on growth performance, carcass characteristics and some blood parameters in broiler chickens in response to heat stress condition. A total of 160 one day-old male broiler chicks (Ross 308) were randomly divided into four treatment groups in a completely randomized design with four replicates of 10 birds each. The experimental treatments including: 1) control (basal diet), 2) the basal diet with Neomycin (200 g/ton), 3) 150 mg/kg Propolis, 4) 200 mg/kg Propolis in diet. Birds submitted to heat stress (32±2ºC from 10.00 AM to 6.00 PM) from 15 to 42 d of age. The results showed that, average mortality was lower in Propolis groups than in the control group (p < 0.05). None of the feed intake data was influenced by treatments during different periods. Birds receiving diet supplemented with 200 mg/kg Propolis had a significantly (p < 0.05) higher body weight compared to the control group at the finisher feeding phase and whole period. In the finisher phase and whole period, the lowest (p < 0.05) fed conversion ratio (FCR) was observed in chickens fed 200 mg/kg Propolis. Cholesterol and LDL level were lower in chickens fed diet with Propolis compared to control (p < 0.05). In conclusion, the addition of Propolis at a rate of 200 mg/kg to the diet could reduce the negative effects of heat stress in broiler chickens.
mahdi dehghani-sanij; Mohammad Ali Norouzian; Ahmad Afzalzadeh; ali assadi-alamouti
Volume 22, Issue 2 , June 2020, , Pages 211-221
Abstract
To study the effects of feeding rumen-protected ascorbic acid and salicylic acid on performance of dairy cows under heat stress conditions, forty four lactating dairy cows in early lactation were allocated in a completely randomized design with 4 treatments and 11 animals in each treatment for 30 days. ...
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To study the effects of feeding rumen-protected ascorbic acid and salicylic acid on performance of dairy cows under heat stress conditions, forty four lactating dairy cows in early lactation were allocated in a completely randomized design with 4 treatments and 11 animals in each treatment for 30 days. Experimental treatments were: 1) control (diet without coated ascorbic acid and salicylic acid), 2) diet contained 30 g/d coated ascorbic acid, 3) diet contained 10 g/d coated salicylic acid and 4) diet contained 30 g/d coated ascorbic acid + 10 g/d coated salicylic acid. Cows were fed with salicylic acid supplement had a higher daily milk yield (51.47 kg/day) compared to other experimental groups (P<0.05). Feeding of coated ascorbic acid increased milk fat percent, glucose, BHBA, NEFA concentration and decreased somatic cell count compared to other treatments (P<0.05). Total milk's solids, energy and fat corrected milk and milk urea nitrogen were increased in coated ascorbic acid group compared to control (P<0.05). Blood urea concentration in coated ascorbic acid and salicylic acid group were less than control group (P<0.05). The results showed that feeding coated ascorbic acid and salicylic acid could improve performance of Holstein dairy cows in early lactating phase under heat stress conditions.
Hassan Lakzaie; Farzad Ghanbari; Javad Bayat Kouhsar; Ashoor Mohammad Gharehbash
Volume 22, Issue 1 , March 2020, , Pages 173-185
Abstract
This research was conducted in order to compare the blood parameters and fattening performance of Zel and Dalagh breeds male lambs (three to four months old), and their crossbred with Romanov in different thermal-humidity conditions. Fattening trial was conducted in Gonbad kavous with four ...
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This research was conducted in order to compare the blood parameters and fattening performance of Zel and Dalagh breeds male lambs (three to four months old), and their crossbred with Romanov in different thermal-humidity conditions. Fattening trial was conducted in Gonbad kavous with four treatments and six replicates for 84 days from mid-August to early November. Based on the temperature-humiity index (THI), the lambs were under very severe and severe of heat stress up to 8th weeks of trial, followed by non-stress conditions (THI index of 25.6 and above that, 23.3 up to less than 25.6 and less than 22.2 respectively). In the very severe heat stress condition, the performance of treatments was the same. In the severe heat stress, the performance of Dallagh lambs and their crossbred with Romanov was better than Zel and Zel-Romanov crossbred (P<0.05). In un-stress conditions, performance traits in Zel Romanov crossbred was lower than other treatments (P<0.05). Glucose and cholesterol concentration were lower when the lambs were in heat stress condition than normal time (P<0.05). Unlike, blood urea concentration in heat stress condition was higher than lack of stress time (P<0.05). Concentrations of nonstratified fatty acids (NEFA) in the middle period of experiment, during severe heat stress, were higher than those of very severe and nonstress periods. In whole of fattening trial period, all of the breeds had lower performance than expected, indicating the effects of heat stress on them. Totally, Dalagh breed lams had better fattening performance than Zel and their crossbred with Romanov, especially under very severe heat stress condition.
Amirhossein Nasiri; Armin Towhidi; Malek Shakeri; Mehdi Zhandi; Mehdi Dehghan banadaky
Volume 20, Issue 2 , August 2018, , Pages 329-337
Abstract
The insulin resistance and glucose, insulin, IGF-1 metabolism (somatotropic axis performance) were investigated in cows to receive (4 g yeast/d/head) (Probio-Sacc®, BioChem, GmbH, Germany) or not receive live yeast supplement from 21 d before expected date of calving under the hot months of summer ...
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The insulin resistance and glucose, insulin, IGF-1 metabolism (somatotropic axis performance) were investigated in cows to receive (4 g yeast/d/head) (Probio-Sacc®, BioChem, GmbH, Germany) or not receive live yeast supplement from 21 d before expected date of calving under the hot months of summer (THI = 82). Two groups of 6 periparturient Holstein cows were fed a diet without or with 4 g yeast/d/head (15*109 CFU/g) starting 21 d prepartum through 8 weeks postpartum to investigate the changes of blood concentrations of glucose, insulin, IGF-1 and glucose tolerance test (GTT). On d 60 postpartum, greater blood levels of glucose, insulin and insulin-like growth factor I were found in cows receiving yeast supplement than those receiving no yeast (P<0/05). Probiotic had not significant effect on GTT test. Overall, it appears that Probiotics would beneficially improve the blood concentrations of glucose, insulin, IGF-1 in day 60 postpartum (on DFS day) and improve somatotropic axis of dairy cows during the heat stress. Probiosac probiotic had positive effects on somatotropic axis and animal performance. It’s can be a good solution to increase dairy cow’s performance in heat stress condition.
Bashir Ghasempour; Abolghasem Golian; Ahmad hassanabadi
Volume 19, Issue 3 , November 2017, , Pages 711-726
Abstract
This experiment was conducted to evaluate the effect of varying levels of digestible protein (DP) and dietary electrolyte balances (DEB) during the finisher period on performance, blood parameters and small intestine histology of broiler chickens exposed to heat stress. A total of 500 mixed sex chickens ...
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This experiment was conducted to evaluate the effect of varying levels of digestible protein (DP) and dietary electrolyte balances (DEB) during the finisher period on performance, blood parameters and small intestine histology of broiler chickens exposed to heat stress. A total of 500 mixed sex chickens (Ross 308) were used in a completely randomized design as a 2×5 factorial arrangement with two levels of DP (%16.5 and %19) and five levels of DEB (150, 200, 250, 300 and 350 meq/kg of diet)with five replicates of 10 birds each during the finisher period. The chicks were exposed to heat stress of 32±2 °C for eight hours/day during 28-42 days of age. Increasing DP levels did not have a significant effect on weight gain under heat stress during the finisher period. Feed intake and feed conversion ratio (FCR) of chickens fed 16.5% DP diet was significantly more than 19% DP fed birds (P<0.05). The highest weight gain and lowest FCR were observed in chickens fed 200 mEq/kg of diet EBD which were significantly different only with 300 and 150 mEq/kg EBD treatments. The highest weight gain was observed in broilers fed diet containing 16.5% DP and 200 mEq EBD. Broilers fed diet containing 19% DP in compare to those fed 16.5% DP had lower plasma triglycerides and higher total protein, creatinine, and uric acid contents. Increasing digestible protein from 16.5% to 19% had no significant effect (P>0.05) on small intestine morphology. Diet containing 250 mEq/kg of diet EBD significantly (P<0.05) increased villi surface of small intestine in chickens suffering heat stress. It is concluded that, feeding of broiler chickens exposed to heat stress during the finishing period with diet containing 16.5% digestible protein and 200 mEq/kg dietary electrolyte balances is recommendable.
Zahra Amiri Ghanatsaman; Omidali Esmaeilipour; Rouhollah Mirmahmoudi; Mozhgan Mazhari
Volume 18, Issue 1 , April 2016, , Pages 119-128
Abstract
This study was conducted to investigate the effect of Mentha piperita (PP) and Melissa officinalis (MP)powder on performance, apparent digestibility of fat and protein and blood parametersof broiler chicks subjected to heat stress. 200-day-old male Ross broiler chicks were assigned to a completely randomized ...
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This study was conducted to investigate the effect of Mentha piperita (PP) and Melissa officinalis (MP)powder on performance, apparent digestibility of fat and protein and blood parametersof broiler chicks subjected to heat stress. 200-day-old male Ross broiler chicks were assigned to a completely randomized design with five dietary treatments and four replicates. The experimental treatments were: 1. Control group (diet without feed additive), 2. Diet supplemented with 0.5 percent PP, 3. Diet supplemented with 1 percent PP, 4. Diet supplemented with 0.2 percent MP and 5. Group supplemented with 0.4 percent MP. The experimental diets were offered to the chicks from 25 to 42 day of age. During the experiment, the birds were kept at 34°C ± 2 for 8 hours (9.00 to 17.00). The diets supplemented by Mentha piperita and Melissa officinalis powder had not significant effect on feed intake, but higher body weight gain (BWG) and lower feed conversion ratio (FCR) observed in the birds fed diet supplemented with one percent of PP. Apparent digestibility of dry matter and crude fat were not affected by the dietary treatments, but the digestibility of protein was increased (P<0.05) in birds fed on diet supplemented with one percent of PP. Dietaryinclusion of PP and MP had no effect on blood parameters. It could be concluded that addition of PP at the level of one percent of broilers diets during heat stress, improve protein digestibility and growth performance.
Mahdiyeh Soltani; Mozhgan Mazhari; Omidali Esmaeilipour
Volume 17, Issue 2 , October 2015, , Pages 291-300
Abstract
Effect of probiotic (Clostat) levels on the performance and immune response of heat stressed broilers, was evaluated in a completely randomized design on 144 day-old male Ross broiler chicks with four treatments and four replicates (nine birds each). Experimental diets were consisted in four levels of ...
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Effect of probiotic (Clostat) levels on the performance and immune response of heat stressed broilers, was evaluated in a completely randomized design on 144 day-old male Ross broiler chicks with four treatments and four replicates (nine birds each). Experimental diets were consisted in four levels of probiotic (0, 0.05, 0.1 and 0.2). Birds were raised under normal condition till 25 days of age and then were exposed to heat stress (34±2°C for eight hours/day) till the end of trial. The results showed that the effect of probiotic on feed intake was not significant, while birds receiving 0.05 and 0.1 percent probiotic had more body weight gain (P<0.05) compared with control birds. Feed conversion ratio (FCR) was better with 0.1 percent probiotic. Increasing probiotic levels, increased relative weight of carcass, breast meat and liver (P<0.05). Blood cholesterol concentration was decreased by probiotic levels (P<0.01). Heterophil and heterophil to lymphocyte ratio was decreased and glutathione peroxidase increased by probiotic addition. It is concluded that dietary supplementation of 0.1 percent probiotic may improve broiler growth performance and immunity under heat stress condition.