broiler chick

The aim of this study was to determine the response of the Ross 308 broilers to β- mannanase containing multi-enzyme with different percentages of nutrient equivalency values of multi-enzyme in corn-soybean based dies. A total of 192 male Ross 308 broiler chicks were used in a completely randomized design with six treatments, eight replicates, and four birds in each. Treatment one (positive control) was a normal corn-soybean meal diet without multi-enzymes. Treatments two, three, four, and five contained 0.3 kg/ton multi enzymes, using 25, 50, 75, and 100% of the nutrients equivalency value of enzyme, respectively. The sixth treatment (negative control) was like to fifth treatment but without added multi-enzyme. Body weight gain and feed conversion ratio (FCR) were assessed weekly. The results indicate, no significant difference among the treatment one and two in body weight gain and FCR. At 42 days of age, the difference in body weight of the negative control group and treatment five was significant (P<0.0001). The similar performance of birds in treatment two despite lower metabolized energy, crude protein, and phosphorus with added enzyme, comparing to the positive control group, indicating that multi-enzyme had the potential for releasing the feed nutrients.

Changes in the pattern of animal protein consumption and a greater tendency to consume chicken in the last decade has greatly increased the demand for this product. Considering that 70% of the cost of poultry production is related to nutrition, so, it can be concluded that optimal nutrition is the most important way to reduce production costs in this industry (Abdollahi et al. 2013). Advances in broiler nutrition and breeding have increased growth rate and reduced breeding period over the past few decades. At present, broilers reach slaughter weight at the age of 42 days. Unfortunately, this high growth rate leads to problems such as metabolic disorders (sudden death Syndrome, skeletal disorders and ascites), increased mortality, and abdominal, and carcass fat (Khajali et al. 2007). Slowing down the growth rate by using dietary restrictions will greatly prevent these problems. At the same time, low growth is not economical and it is necessary to compensate for the backward growth of chickens due to food restrictions. Researchers have stated that the main goal of research on dietary restriction in broilers is to improve feed efficiency and reduce carcass and abdominal fat (Zhan et al. 2007). Depriving birds, especially broilers, of rapid growth from full access to the nutrients needed for normal growth is called feed restriction, which is classified into two categories: quantitative and qualitative. The response to feed restriction depends on the duration of the feed restriction (Khetani et al. 2009). In quantitative or physical feed restrictions, the consumption of birds or animals is limited. The practical application of physical feed restriction is not easy due to the problems of regular weighing of poultry and calculating daily feed intake (Zulkifli et al. 2000). Quality restriction is another method of applying feed restriction that aims to use diets with low energy and protein levels (Fanooci and Torki 2010). Urdaneta-Rincon and Lesson (2002) y applying 85, 90 and 95% quantitative feed restriction in male broilers at 5 to 42 days of age, they showed that the application of dietary restriction led to a significant difference in weight at 42 days of age and also a significant reduction in mortality. Bautzen et al (2003) in an experiment on broiler sex mixture and the application of quantitative feed restrictions at the ages of 6 to 16 days and 80% of the previous day's consumption of the control treatment, showed that performance was affected in the early weeks, but the restricted treatments at the age of 42 One day, they achieved the desired compensatory growth and no difference with the control group. Therefore, according to the reports on the use of feed restriction in reducing metabolic diseases and losses, it seems necessary to study feed restriction in broilers. In order to evaluate the effects of quantitative feed restriction, 300 one-day-old Ross broilers were each in a completely randomized design with five treatments, five replications and 12 pieces per replication for 42 days. The birds were fed ad-libitum up to 10 days then they were restricted from 11 to 35 days and they were fed ad-libitum up from 36 to 42 of age. Experimental treatments include: (1) Corn- soybean meal – based diet as a control group (no feed restrictions), (2) feed access to 95% control group, (3) feed access to 90% control group, (4) feed access to 85% control group (5) feed access to 80% control group. Diets were prepared according to the maintenance guidelines of Ross 308 strain. At 42 days of age, one chick from each pen was randomly selected and slaughtered, and the carcass traits such as breast, thigh, gizzard, liver, abdominal fat and carcass yield were determined. On day 35 of the breeding period, one chick from each experimental unit was randomly selected and slaughtered. The cecum of the birds was isolated and examined for the microbial population of Lactobacillus, Coliform and E. coli in the laboratory. Blood samples were also collected and then, centrifuged at 3000 rpm for 10 minutes and transferred to the laboratory to determine blood parameters (Cholesterol, Triglyceride, HDL and LDL). On day 35 of the experiment, some samples were collected and transferred to the laboratory to determine the percentage of dry matter, moisture, ash and volatile solids. To sample the waste, two hours before sampling, it was placed on the bed of each plastic pen and the waste were collected from five points of each pen. Experimental data were statistically analyzed in a completely randomized design using GLM procedure by software (SAS 2004) and the means were compared by Duncan's multiple range test at 5% probability level. The results showed that feed restriction decreased feed intake and body weight gain comparted with the control group (P<0.05). Carcass characteristics, FCR and feces characteristics were not affected by Feed restriction (P>0.05). Also, feed restriction at the levels of 85% and 80% significantly decreased protein excretion in comparison with the control group (P<0.05). Feed restriction at the level of 80%, increased cecal populations of Lactobacillus spp. While decreased cecal populations of E. coli (P<0.05). Feed restriction decreased blood triglyceride and increased blood LDL (P<0.05). Quantitative feed restriction clearly affected body weight gain and feed intake of birds. The degree of change in these parameters depended on the level of feed restriction used. There was a reduction in body weight gain at 42 d for chicks restricted to 95, 90, and 85%, of ad libitum feed intake, relative to the previous day’s intake of the control birds. Such a reduction in body weight is in accordance with results from Khantaprab et al. (1997), Roth et al. (1993), and Santoso et al. (1993a). Results suggest that the growth rate of broiler chickens is related to feed intake, which supports the statement that improvement in body weight of birds is highly correlated to feed consumption (O’Sullivan et al, 1992). Overall the results showed that although feed restriction up to 80%, decreased feed intake and body weight gain of broiler chickens at the total period of experiment, but this restriction improved microbial population of cecum, decreased blood LDL and protein excretion.

Bacillus coagulans is a new strain of the probiotics group that in addition to being spore-forming, stimulates the secretion of lactic acid in the digestive system.This experiment is performed to assess the effect of Bacillus Coagulans on the functional traits and microbial flora of the gastrointestinal tract of Ross 308 broilers.

In order to assess the effect of Bacillus coagulans probiotic supplement on the feeding of broiler chicks, an experiment is conducted on 960 chicks including 12 replications of 20 chicks. The nutritional periods consist of starter (1-10 days) , grower (11-25 days) and finisher (26-42 days). To implement the experiment , The experiment was conducted on Ross 308 male chicks with average weight of  40±0.12 gram and in a completely randomized manner in four treatment groups. Experimental groups are 1) basal diet without consuming bacillus coagulans, 2) basal diet with adding probiotic supplement at the rate of 400 g/ton feed in starter and grower periods and 200 g/ton feed in finisher period, 3)basal diet adding probiotic supplement at the rate of 400 g/ton feed in starter and 200 g/ton feed in grower and finisher period and 4) basal diet adding probiotic supplement at the rate of 200 g/ton feed in starter, grower and finisher periods. Production traits consisting of body weight gain, feed intake and feed conversion ratio are measured at the end of each period of starter, grower and finisher. On days 7 and 40, two chicks from each replicate are slaughtered using carbon dioxide gas and the cecum was isolated. The samples sent to the laboratory under specific protocols to count clostridium perfringens, E.coli, salmonella, streptococcus and lactobacillus. Furthermore, the cloaca temperature of all the remaining chickens of the experiment project is measured on the day 40 of experiment. Total excreted nitrogen and pH of litter contents are measured on the day 40.

Consumption of Bacillus coagulans had no meaningful effect on weight gain of chickens up to 42 days of age, but compared to the control group, the groups that consumed Bacillus coagulans showed higher weight gain. In the starter and final period, consumption of Bacillus coagulans led to the reduction of feed intake (p≤0.05). At day 42, groups that consume Bacillus coagulans had lower conversion rates than control group. Adding Bacillus coagulans to the diet of broilers at day 40 had a meaningful effect on increasing the population of lactobacilli1 (p≥0.05). On the other hand, consumption of Bacillus coagulans reduced the bacterial population of Clostridium, Streptococcus and Escherichia coli (p≥0.05). The results of this experiment show that broilers receiving Bacillus coagulans produced lower rate of nitrogen fecal escape than control group (p≥0.05). Additionally, the use of this bacterial compound in the diet of broilers reduced the cloaca temperature of chickens compared to the control group (p≥0.05). Adding this bacterium to the diet of broilers had no effect on pH litter (p>0.05).

The achieved results of this research indicated that dietary supplementation with Bacillus coagulans led to increase body weight gain and decrease FCR , balances the beneficial microbial population of the gastrointestinal tract, reduces gastrointestinal inflammation and improves digestibility.

The current study was conducted to evaluate the effects of dietary inclusion of eucalyptus and marshmallow leaf powder on growth performance and blood biochemical parameters of broiler chickens with four treatments, five replicates, and 10 chickens in each (n=200), based on a completely randomized design. The chickens were fed one of the four experimental diets including 1. Control (basal diet), 2. Basal diet+0.5% eucalyptus leaf powder, 3. Basal diet+0.5% marshmallow leaf powder, and 4. Basal diet+0.5% eucalyptus leaf powder and 0.5% marshmallow leaf powder. During three experimental periods (starter: 1 to 21 d, grower: 22 to 42 d, and whole periods: 1 to 42 d), growth performance parameters were measured. At the 42 d, blood samples were taken from one bird per cage to measure blood parameters. There was no significant effect of dietary treatments on growth performance parameters, and blood levels of albumin, triglycerides, uric acid, and glucose. Eucalyptus and marshmallow leaf powder (separately or in combination) decreased LDL level compared to the control group (26.60, 23.60, and 25.40 mg/dL, respectively). Simultaneous usage of eucalyptus leaf powder and marshmallow leaf powder in the diet increased blood HDL (24.60 mg/dL) and reduced blood cholesterol (47.14 mg/dL) values compared to the control group. In conclusion, usage of eucalyptus leaf powder (0.5%) and/or marshmallow leaf powder (0.5%) had no effects on feed intake, daily gain, and feed conversion ratio; however, they decreased blood LDL. Besides, 0.5% eucalyptus leaf powder and 0.5% marshmallow leaf powder could increase and decrease blood HDL and cholesterol, respectively.

This study was conducted to evaluate the effect of spearmint and eucalyptus essential oils on growth performance, carcass traits and immune system performance of broiler chickens under heat stress conditions. Two hundred and fifty one day-old broilers (Ross- 308) were randomly divided into five treatments in five replicates with 10 birds per replicate from 1 to 42 days of age, in a completely randomized design. Treatments included: 1. Negative control (under normal temperature conditions), 2. Positive control (under heat stress conditions), 3. Positive control+0.5 mL spearmint essential oil per liter of drinking water, 4. Positive control+0.5 mL eucalyptus essential oil per liter of drinking water, and 5. Positive control+0.5 mL spearmint essential oil+0.5 mL eucalyptus essential oil per liter of drinking water. Heat stress was applied in the grower period (26-42) at 32 ± 1 °C (9 am to 5 pm). The results showed that in the grower period and the entire trial period, heat stress reduced feed intake (P<0.05). Thermal stress increased the relative weight gain of the entire intestine and decreased the relative weight loss of the thighs (P<0.05), also reduced the lymphocyte proliferation and survival (P<0.05), and decreased the intensity of peripheral blood phagocytic respiration (P<0.01). However, the use of eucalyptus essential oil and a mixture of two essential oils (eucalyptus+ spearmint) improved the lymphocyte propagation and compensated for the reduction of heat stress (P<0.05). In addition, the combined use of spearmint and eucalyptus essential oil improved the intensity of respiratory explosion in macrophages compared with negative and positive control treatments (P<0.01). In general, the use of essential oils improved immune function but did not affect the performance of broiler chicks.

The aim of this study was to investigate the effects of pomegranate seed pulp (PP) and its treated form with urea (PPTU) on performance, blood biochemical parameters and immune response of broiler chickens reared in heat stress condition. A total of 280 day-old Ross 308 chicks were used in a completely randomized design. The chicks were equally divided into seven treatments including 0, 3, 6 and 9 percent of PP and 3, 6 and 9 percent of PPTU with four replicates and 10 birds each. In heat stress period (25-42 days), the daily heat stress schedule was applied from 10:00 until 17:00 h for seven hours (35-37 oC). The PPTU increased the blood concentration of total protein (11 vs. 15.7 mg/dL). In heat-stressed chickens, PP increased body weight (1498 vs.1020 g) and decreased feed conversion ratio (1.82 vs. 2.56). The PP decreased the blood glucose concentration (611 vs. 1106 mg/dl) and also decreased the activity of the liver enzymes including alkaline phosphatase (1667 vs. 6483 U/L), aspartate aminotransferase (259.9 vs. 674.8 U/L) and lactate dehydrogenase (1506 vs. 3288 U/L). The immune response to SRBC in chickens fed PP with enzymes (9.25) or its urea-treated (8.5) were higher as compared to control (6.75). Therefore, these findings showed that the addition of pomegranate pulp with enzyme or its treated with urea up to 9% may improve performance, immune response and decreased the activity of liver enzymes in heat stressed broilers.

In ovo feeding is considered as a useful tool to overcome the growth limitations during embryonic growth and after hatching in domesticated poultry. Therefore, the purpose of the present study was to investigate the effect of different levels of DL- methionine on the morphology of small intestine in ROSS 308 broiler chicks. In this regard, the total number of 240 eggs from Ross 308 broiler breeder were used according to a completely randomized design (CRD) with 8 experimental groups and 30 eggs per each treatment. The experimental treatments included different levels of DL-methionine amino acid (0.19, 0.38, 0.57, 0.76, 0.95 and 1.14 %), along with a sham-control group (sterile water injection) and a control group (without injection) which were injected into the amniotic fluid on the 14th d of incubation. After hatching, the chicks were weighed and slaughtered to measure small intestine morphological characteristics. Results of the study indicated that in ovo feeding of DL-methionine had a significant effect (p<0.05) on hatchability, weight and relative weight of jejunum, small intestine weight, as well as crypt diameter (except for duodenum), villus height, crypt depth, villus height to crypt depth ratio, and villus thickness in duodenum, jejunum, and ileum. On the other hand, no effect of treatments (p>0.05) was observed on chick weight and weight and length indexes of duodenum and ileum. Based on the results of this study, the best morphological response was observed in 76% DL-methionine treatment.

The aim of this experiment was to determine the digestible valine requirement of male Ross ‎‎308 broiler chicks in grower period. To evaluate valine requirement of male broiler chicks ‎based on growth performance, a total of 450one day old male broiler chicks from8 to 21days ‎of age, was assigned to 6 treatments with 5 replicate using a completely randomized design. ‎Dietary valine was supplied in 6 levels from 0.74, 0.79, 0.84, 0.89, 0.94 and 0.99for the ‎experimental period. Results of this study showed that the quadratic broken line model were ‎used for determine of digestible valine requirement for Ross 308 male broiler chicks is the well ‎fitted base on weight gain, feed conversion ratio and breast weight and Evaluated digestible ‎valine content for these three performance parameters were 0.93, 0.91 and 0.84 % of diet ‎‎(Val/lys were 88, 86 and 79%), respectively. The result of this experiment showed that the all ‎performance parameters and cell modified immune response were significantly affected by the ‎valine supplementation in diet (P< 0.01). The broiler chickens fed with 0.89 % of digestible ‎valine level had the highest cell modified immune response (1.13±0.05 mm) and the lowest ‎feed conversion ratio (1.42±0.02) (P<0.01), and also The broiler chickens fed with 0.74 % of ‎digestible valine level had the lowest cell modified immune response (0.44±0.03 mm) and the ‎highest feed conversion ratio (1.60±0.06). ‎

Effect of energy expression system and total amino acid database on economical efficiency of Ross 308 broilers strain was studied by 180 broiler chicks in a completely randomized design with a 2×3 factorial arrangement. This study was performed with six treatments, three replicates and 10 broiler chicks in each replicate. Experimental groups included two systems of energy (AMEn and TMEn) and three amino acid database (NRC, Evonik and Ajinomoto) in the periods of starter (1 - 10 days), grower (11 - 24 days) and finisher (25 - 42 days). Dietary formulation with AMEn caused significant increase in feed intake (3983.2 g) and weight gain (2358.3 g) of broilers. In 24 and 42 days, dietary formulation with AMEn and then TMEn caused increase in revenue and the cost of broilers’ ration. Dietary formulation according to TMEn caused a significant increase in profitability (3690.2), gross profit share of revenue (42.367), profit share of variable costs (74.100) and gross profit returns (10.173) as well as a significant reduction in the cost of meat production (2.19) (P

This experiment was conducted to investigate the effect of using 2% untreated and treated corn gluten meal with protease enzyme (300 mg/kg) at three different times (120, 180 and 240 minutes) on broiler chicks performance, carcass characteristics and some blood parameters. 240 commercial strains Ross 308 male broiler chicks with five treatments including: 1. control diet, 2. control diet containing 2% corn gluten, 3, 4, and 5. control diet containing 2% corn gluten meal processed with protease enzyme at 120, 180 and 240 minutes, respectively, four replicates and 12 chicks in each replicate in a completely randomized design were reared for 38 days. During the experiment, feed intake, body weight gain and feed conversion ratio were measured. To evaluate blood parameters and carcass components at 38 d, eight birds from each treatment were selected and after blood samples collection, some blood parameters such as glucose, total protein, albumin, globulin, triglycerides, cholesterol, HDL-C, LDL-C and VLDL-C were measured and also, carcass components including weights of carcass, thighs, breast, abdominal fat, liver, pancreas, spleen and Bursa Fabricius were determined. Results of this study indicated that treatments containing 2% corn gluten meal with protease enzyme processing at different times, increased feed intake (3801.98, 3848.59 and 3850.42 vs. control diet 3769/82 g), body weight gain (2000.88, 2020.16 and 2033.27 vs. control diet 1888.82 g), and reduced feed conversion ratio (1.90, 1.90 and 1.89 vs. control diet 1.99) in total period of the experiment (P

The aim of this experiment was to determine the total leucine requirement of male Ross 308 ýbroiler chicks. To determinate valine requirement of male broiler chicks based on growth ýperformance, a total of 250 male broiler chicks from 24 to 39 Days of age, was assigned to 5 ýtreatments with 5 replicate using a completely randomized design. Wheat-corn-soybean meal-ýbased diet was formulated to provide the all nutrient except leucine, based on Ross 308 ýmanagement guide. Dietary leucine was supplied in 5 levels from 1.16 to 1.36 % for the ýexperimental period. In the experimental period weight gain, feed intake, feed conversion ýratio and feed efficiency ratio were determined. Result of this study showed that the liner ýbroken line model were used for determine of total leucine requirement for Ross 308 male ýbroiler chicks is the well fitted base on weight gain, feed intake and feed conversion ratio, and ýevaluated leucine content for these performance parameters were 1.217, 1.218 and 1.213 % of ýdiet, respectively. The result of this experiment showed that the uric acid of chickens was ýsignificantly affected by the Leucine supplementation in diet (P

Recently, many countries tended to minimize or prohibit the chemical components for their deleterious side effects on both animals and human. So, it is important to use natural promoters. Herbs and its by products were found to have useful effects, e.g., antioxidant, growth promoters (Habibi et al. 2014), Immunostimulants (Habibi et al., 2016) tonics, antiparasitic, anti-bacterial, carminative, anti-fungial, anti-microbial and antiseptic (Jafarnia et al. 2007). Medicinal plant competes with the synthetic drugs. (Habibi et al. 2014). Eucalyptus (Eucalyptus globulus) of the Myrtaceae family is an important medical herb in world and has antioxidant, anticholestrol and antimicrobial properties (Jafarnia et al. 2007). Eucalyptus leaves used to produce essential oil. Essential oil of eucalyptus leaves contain effective compounds such as 1,8 cineol, Limonene, o-Cymene and α-pinene, that main composition of its is eucalyptol (1,8 Cineole). constituting the 60–90%, that has been reported to inhibit the production and synthesis of tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), leukotriene B4, and thromboxane B2 in human blood monocytes (Serafino et al. 2008). Eucalyptus essential oil proved to be able to implement innate-cell mediated, humoral immune response and have a potent immunomodulatory effect in chickens (Awaad et al. 2010). This study was conducted to investigate the effects of different levels of eucalyptus (Eucalyptus globules) leaf powder on performance, carcass characteristics and immune response of broiler chicks.
Material and A total of 240 one day male broiler chicks (Ross-308) provided by a local commercial hatchery were randomly allocated to one of the 5 experimental treatments. Each treatment condition consisted of 4 replicate pens with 12 birds each. Experimental treatments included: Control (corn-soy meal based diet) and treatments containing diets supplemented with 0.25, 0.5, 0.75 and 1 percent of eucalyptus leaf powder. The composition of the basal diets is presented in Table 1. Chicks were provided with ad libitum access to water and feed. The birds were reared on concrete flooring covered with wood shavings as litter material. The body weight and feed consumption of the birds were recorded at 10, 24 and 42 days of experiment period. Two birds per each replicate were randomly selected and then slaughtered. Organs were removed and weighed from each bird. Weight of the organs were expressed as a percentage of live body weight. The SRBC (sheep red blood cell) test was performed to quantify the specific antibody titre for injection of SRBC, at first 30cc of phosphate buffered saline (PBS) solution with 10cc of SRBC completely mixed and 0.2 cc of the obtained solution drawn into the syringe was injected into the breast muscle 4 bird per treatment in 20 and 30 days of age. Whole sheep blood collected in solution was washed three times in PBS with pH=7.4 and diluted in PBS to 25 %. Therefore, 7 days after each sensitization (27 and 37 days) were bled for assessing haemagglutination (HA) titre against SRBC by using freshly prepared one percent SRBC. The test serum (25μl) was serially diluted 1:2 with PBS in microtiter plates. After dilution, 25 μl of 1 % SRBC was added to each well and mixed. The plate was incubated at 37°C for 1 hour and haemagglutination titre was expressed as the log2 of the reciprocal of the highest dilution showing 100 percent agglutination (Yamuna and Thangavel 2011). All data were analyzed according to GLM procedure of SAS (SAS Institute, 2004), version 9.1. The Duncan’s Multiple Range Test was used to compare means when significant effects (P Experimental treatments had no effects (P>0.05) on the amounts of weight gain, feed intake and feed conversion ratio (Table 3). There was no significant difference between treatments in carcass characteristics and relative weight of immune organs at 42 days of age (P>0.05). This results were in agreement with Yaghoobzadeh et al (2004) who observed an non significant improvement in the body weight gain of chicks fed diets supplemented with eucalyptus powder and its by products, however carcass traits relative weight was not affected by the inclusion of eucalyptus in the diet. Also, Koopaie et al (2011) reported that eucalyptus essential oil has positively influenced growth performance in broilers. Birds were received 0.5% of eucalyptus leaf powder, had highest antibody concentration versus sheep red blood cells (SRBC) and its difference was significant with control group (P0.05). At 37 days of age, treatments contained 0.5, 0.75 and 1% of eucalyptus leaf powder, had higher antibody concentration than control group (P Results of the present study indicated that usage of eucalyptus leaf powder in 0.5 percent concentration, caused improvement and reinforcement immune response, however had no significant effect on performance and carcass traits of broiler chicks.

Improving in quantity and quality of meat production concomitant with augmenting in immune system are of great importance for both consumers and producers.
The present study was designed to investigate the effects of dietary L-arginine supplementation on meat quality, intestine histology and immune system of female Ross 307 broiler chickens.
A total of 192 day old chicks were fed with 4 dietary treatments and 4 replicates by employing a completely randomized design. Dietary treatments included 100%, 153%, 168% and 183% of digestible arginine, based on the Ross catalogue recommendation, and were fed from day 1 to 46 of age. At day 46 of experiment, three chickens per replicate were randomly selected and euthanized in order to determine meat quality, immune system tissues’ weight and weight, length and histology of small intestine.
The results showed that increasing arginine content of the diet had a significant increasing effect (P According to the results, consumption of 168% digestible arginine, based on the Ross catalogue recommendation, can improve meat quality, digestive capacity of small intestine, and immunity.

This research was conducted to investigate the effects of SAF Mannan prebiotic and Liptol HPA organic acid on performance¡ carcass traits and intestinal morphology of broiler chickens. In this experiment¡ 160 one-day-old Ross-308 broiler chicks were allocated to 4 treatments¡ 4 replications and 10 Chicks each by employing a completely randomized design for a period of 42 days. Experimental diets including: control diet (no additive) and diets containing 0.1% prebiotic¡ 0.1% organic acid and 0.1% mixed of prebiotic and organic acid. Feed intake (FI)¡ weight gain (WG) and feed conversion ratio (FCR) were determined periodically and carcass characteristics¡ productive index (PI) and intestinal morphology was measured at 42 days of age. Results indicated that¡ there were no significant differences between treatments in FI. The highest WG was observed for diet containing organic acid (P

The purpose of this study was to investigate the effect of Enterococcus facium isolates from intestine of Coracias Garrulus(SE) and lactofeed probiotic on performance and carcass characteristics parameters of broiler chickens. A total of 280 chicks were arranged into 28 experimental units with 7 treatments in a completely randomized design. The treatments were included control, spraying Lactofeed, drinking Lactofeed and spraying drinking Lactofeed(LF) and spraying SE, drinking SE and spraying drinking SE. Spraying and drinking suspension with 1×1011 cfu were done on 1, 10, 24 and 35 days. The blood of two birds from each replicate was gathered at 28 and 42days. The body weight was increased when birds received SE and LF. The FCR were lower in birds received drinking probiotic and in spraying drinking SE as compared to control. The addition of SE and LF were decreased the serum cholesterol (176 vs, 121 and triglyceride (105 vs. 65)concentration of broilers. The antibody response against SRBC was increased in birds received SE and LF (8.12 vs. 5.83. The jejunum population of gram positive (4.05 vs. 18.38) and gram negative bacteria (13.68 vs. 4.99) were increased and decreased, respectively, in experimental treatments. It is concluded that supplementation of Enterococcus faciumisolates or lactofeed probiotic to water of chicks or spraying may improve the body weight and FCR, immune system and jejunum microflora of broiler chickens.

The aim of this study was to survey the effects of different levels of Stevia alcoholic extract on performance and humoral immune system of broilers. Two hundred one-day chicks (Ross 308) were studied in a completely randomized design with 5 treatments, 4 replications and 10 chicks per replicate. The treatment groups received 0 (control), 0.5, 1, 1.5 and 2 mL/L of Stevia extract, in drinking water, during days 3 to 42. Daily feed intake, daily body weight gain, feed conversion ratio and carcass characteristics were measured. The birds were immunized by sheep red blood cell (SRBC) on days 12 and 29 of age and serum antibody levels produced in response to SRBC were measured on days 28, 35 and 42. Newcastle vaccine was given on days 1, 6, 18 and 29 to chicks and blood samples were collected at 42d. Antibody titer against Newcastle virus was determined by the HI method. Result indicated that Stevia alcoholic extract hadn’t any significant effect on performance (P>0.05). All experimental groups increased antibody titer against Newcastle virus (P<0.05). Consumption of 1.5 and 2 mL Stevia extract increased anti SRBC titers (P<0.05). It is concluded that Stevia alcoholic extract had no significant effect on performance, but improved humoral immunity of broilers.

The objective of the present study was to investigate the effects of high dietary levels of L-arginine during starter period on growth، intestine morphology and immune system of female Ross broiler chicks. In this experiment، 192 day old female Ross broiler chicks were fed with 4 dietary treatments in a completely randomized design، in which each dietary treatment included 4 replications. Dietary treatments included 100%، 153%، 168% and 183% of digestible arginine، based on the Ross recommendation، and were fed from day 1 to 10. On d 10 of the experiment، chicks were weighed and feed consumption was recorded. Then، three chicks per replication were slaughtered in order to survey intestinal histology and immune system. The results showed that high dietary levels of arginine had an increasing effect (P<0. 01) on 10th day body weight، feed efficiency، immune system characteristics، weight and length of small intestine، and its villus height and crypt depth. According to the results of this study، 168% digestible arginine، based on the Ross recommendation، had the best desirable results on growth improvement of broiler chicks and it also improved weight، length and histology of small intestine، and immune characteristics.

This experiment was carried out to investigate the effects of in yolk-sac administration of olive oil (0 and 0. 7 ml) on productive performance and breast development of broiler chickens exposed to post-hatch fasting stress (0، 12، 24، 36 and 48 hours). A total number of 800، 1-day-old broiler chicks in a completely randomized block design with 10 treatments and 4 replicates were used. Live body weight of broiler chicks exposed to 24 and 36 hours post-hatch fasting was significantly lower compared to control group (P<0. 05). Extending of post hatch fasting up to 48 hours induced compensatory growth in broiler. Administration of olive oil to yolk sac significantly increased mortality rate and negatively affected production efficiency index (P<0. 05). In day 28، fasting and administration of olive oil showed no significant effect on breast external dimensions and on major and minor pectoral is muscles weight (P<0. 05). It is concluded that 24 and 36 hours Post-hatch fasting had negative effect on broiler performance and that injection of 0. 7 ml olive oil was reduced performance of broiler chickens exposed to post-hatch fasting.