aliasghar saki

This study was conducted to investigate the effect of licorice (Glycyrrhizaglabra) extract, Active-mos®prebiotic, and flavomycin antibiotic on performance, egg quality, and body mass status in the pre and early laying periods. A total of 180 Leghorn pullets (Hy-line W-36), were assigned into 6 treatments (5 cages/treatment, 6 pullets/cage) in a completely randomized design. The experimental treatments included control (feed additive-free- diet), and control supplemented by licorice extract (5 and 10 g/kg of diet; as LIEX5 and LIEX10, respectively), flavomycin antibiotic (400 and 650 mg/kg of diet; as FL400 and FL650, respectively), and Active-mos®prebiotic (1 kg/ton of diet; as ACPR). Birds were raised in a cage-layer facility. Body weight, feed intake, and feed conversion ratio were determined weekly. Body mass index was recorded before and after using the treatments. Also, the growth, egg quality, egg cholesterol, serum cholesterol, and triglyceride were tested. During weeks 18 to 19 of age, birds received control, FL650, and ACPR treatments showed greater feed intake compared to LIEX10. The body weight of birds that received FL400 diet was greater than LIEX5 and ACPR treatments at weeks 17 to 19 of age. All treatments, except for ACPR, decreased serum cholesterol compared with the control treatment (P < 0.05). No significant effect on feed conversion ratio, egg production, and body mass index was observed by treatments throughout the study (17-25 wk). Furthermore, there was no significant effect of treatments on the eggs' internal and external quality status, egg cholesterol, and serum triglyceride by treatments. However, more research is needed on the use of licorice extract and prebiotics as antibiotic alternatives and their effects on the body mass index in laying hens during pre- and early-laying periods.

This study was conducted to estimate digestible arginine (Arg) requirements for performance and egg quality parameters in Hy-Line W-36 laying hens from 40 to 46 weeks of age. A total of 150 laying hens were arranged in a completely randomized design with 5 treatments, 5 replicates and 6 hens in each. These treatments included 0.81, 0.86, 0.91, 0.96, and 1.01 % digestible Arg. At the end of experiment, data were obtained in performance, egg quality, and quantity parameters as well as plasma levels of cholesterol, uric acid, globulin, and insulin-like growth factor (IGF-1). Results have shown that feed conversion ratio, egg production, and egg mass improved by supplementing 0.86 digestible Arg in the diet compared to other treatments (P < 0.05). Moreover, these items significantly affected by the interaction of treatments and weeks. In the last three weeks of this experiment, the use of 0.86, 0.91, 0.96, and 1.01 % digestible Arg significantly increased egg mass and egg roduction. Plasma concentrations of globulin, cholesterol, and uric acid were not affected by dietary Arg levels. However, a significant increase in plasma IGF-1 was shown by supplementation of % 0.91 Arg (P < 0.05). Based on quadratic equations, the optimum levels of digestible Arg for egg production, egg mass, feed conversion ratio, and IGF-1 were 0.917, 0.917, 0.908, and 0.970%, respectively.

The effects of dietary insoluble fiber sources on growth performance, gastrointestinal tract (GIT) traits, nutrient digestibility and intestinal enzyme activity were studied in broilers from 1 to 42 d of age. A total of 480 one-day-old chicks (Ross 308), were allocated in four treatments, six replicates and 20 birds in each, based on a completely randomized design. Dietary treatments were including a corn-soybean meal basal diet (control diet) and other three diets formulated by the inclusion of 30 g/kg of processed wheat straw (WS), sunflower hulls (SFH), or soybean hulls (SBH) in the control diet. From 1 to 10 d of age, broiler chickens fed processed WS tended to have higher feed intake than broilers fed the control diet (P = 0.064) and had higher body weight gain than broilers fed the other treatments (P < 0.05). The relative weight of the GIT organs was not affected by treatments but SFH and SBH decreased the length of the small intestine at 42 d of age (P < 0.05). The pH of different segments of the GIT, carcass traits, dry matter, nitrogen digestibility, and apparent metabolizable energy corrected by nitrogen were not affected by treatments. The activity of amylase and aminopeptidase in the duodenum and jejunum was not affected by the insoluble fiber sources. In conclusion, the dilution of the control diet with the inclusion of 30 g/kg insoluble fiber did not have any negative effect on broiler chickens' performance and marketing weight. Moreover, improved performance was observed with processed WS, particularly during the starter period.

The objective of this study was to investigate the effects of dietary zinc (Zn) sources and levels supplementation on performance, egg quality, blood parameters, and egg yolk Zn content in laying hens from 28 to 36 weeks of age. Two hundred laying hens (Hy-Line W-36) were weighed individually and placed randomly in cages with five treatments, five replicates of 8 birds in each by 2×2+1 factorial arrangement. Treatments consisted of a control diet (corn-soybean meal as a basal diet without Zn supplementation) and the diet supplemented with 80 and 120 mg of Zn/kg, added as either Zinc-sulfate (ZnSulf) or Zn-methionine (ZnMet), respectively. No significant differences were observed for treatments on laying hen performance from 28 to 36 weeks of age. Eggshell thickness significantly improved (P<0.001) by ZnMet in comparison to ZnSulf. Eggshell thickness significantly improved by increasing Zn from 80 to 120 mg/kg of the diet (P<0.05). Plasma HDL (P<0.001), alkaline phosphatase activity (P<0.05), total protein, and albumin concentrations (P<0.001) were significantly increased by ZnMet in comparison to ZnSulf supplementation. Plasma Fe, Cu, Zn, P and Zn content of the egg yolk were not affected by Zn sources or levels. Plasma Ca was higher in hens receiving 120 mg/kg ZnMet/kg than other treatments (P<0.01). In conclusion, more positive effects on eggshell quality and some blood parameters were found by dietary ZnMet supplementation at 80 or 120 mg/kg diet than ZnSulf in laying hens under the conditions of this study.

A study was conducted to evaluate the effects of Bacillus amyloliquefaciens on adverse effects of aflatoxin B1 in broiler chickens. A total of 480 1-d-old broiler Ross 308 (male and female) were completely randomized disgine with a 2× 2 × 2 factorial arrangements (sex and feed additives) with 4 replicates of 15 birds. Factors includes sex (male and female); probiotic (control, 108 cfu/mL B. amyloliquefaciens); aflatoxin (control, 500 AFB1 µg/kg), Performance, the activity of liver enzymes, immune and some blood parameters were not affected by sex (p> 0.05). Body weight and feed intake of aflatoxin B1 group were significantly decreased compared other (p< 0.05). There was no significantly drffenece in feed conversion ratio compared with other groups during total period (p>0.05). Activity of liver enzymes including aspartate amino transferase, alanine amino transferase, alkaline phosphatase and lactate dehydrogenase were significantly increased in aflatoxin B1 group (p<0.05). The counts of red blood cells and withe blood cells, hematocrite and hemoglobin percentages were significantly decreased in aflatoxin B1 group compared with other (p<0.05). The aflatoxin B1 group has shown the lowest of antibody production against newcastle disease and sheep blood red cell also, the lowest of skin thickness in responding to phytohaemagglutinin (p<0.05). In conclusion, the supplementation of B. amyloliquefaciens to contaminated food could be improved performance and increased the activity of liver enzyme and immune response in broilers.

n order to investigate the effect of in ovo injection and utilization of different levels of licorice extract (LE) (Glycyrrhiza glabra) and colloidal nano silver (CNS) on performance and some blood parameters of broilers during embryonic and growth periods as substitution for Flavomycin®, an experiment was conducted using eight hundred Ross-308 Fertilized eggs as factorial with completely randomized design with 10 treatments and 4 replicates of 20 eggs in each.The treatments of in ovo injection stage consisted of LE (0, 100 and 200ppm) and CNS (0, 30 and 60ppm), negative control group (without injection) and positive control group (injection of 0.1ml sterilized distilled water).The treatments of growth period consisted of LE (0, 1 and 2gr/kg) and CNS (0 and 120ppm), treatment containing 450 ppm antibiotic Flacomycin® and two control group from embryonic period.The results showed that the injection of 100ppm LE+ 60ppm CNS significantly increased hatchability percentage(P<0.01) when compared with groups treated with LE and CNS.The chickens body weight and length after hatch were increased significantly in all treatment especially in treatment containing the highest levels of CNS and LE (P<0.01).The highest FCR was observed in group treated with 450mg/kg antibiotic Flacomycin® and negative control(P<0.01) and the lowest FCR was observed in treatment containing 120 mg/kg CNS and treatment containing 2gr/kg LE+ 120mg/kg CNS(P<0.01).The HDL concentration was increased by treatment containing 100ppm LE(P<0/05).Generally, licorice and colloidal nano silver could improve performance and carcass characters via upgrade physical conditions of chicken and can be considered as a substitute for antibiotic Flavomycin.

The purpose of this experiment was to compare the effects of essential oils blend with probiotic and Flavomycin as antibiotic growth promoter on humoral immunity, meat quality, and some blood parameters in broiler chickens. A total of 288 day-old Ross 308 strain broiler chicks based on a completely randomized design was allocated to four treatments with four replicates and 18 birds in each replicate. Treatments were included: 1) control (a basal diet containing corn and soybean meal without additive), 2) basal diet + 150 mg/ kg essential oils, 3) basal diet +200 mg/ kg probiotic Gallipro®, and 4) basal diet +150 mg/ kg Flavomycin. In order to evaluate humoral immune response, antibody titers of sheep red blood cells (SRBC) were measured by hemagglutination method at 26 and 33days. In order to evaluate blood parameters and meat quality, two birds per replicate were slaughtered and blood samples were collected.  Humoral immune response was not significantly different between groups (P >0.05). Redness index (a*) in thigh muscle and pH of breast muscle 24 h after slaughter decreased (P<0.05) in treatments 2 and 3 compared with 1 and 4. Plasma concentration of HDL was significantly lower by 4 treatment than other groups (P < 0.05). Generally, the results of this study showed that dietary supplementation of essential oils blend, probiotic and Flavomycin to broiler chickens did not affect immune response of the birds, but pH of meat was improved after slaughter. In addition, Flavomycin supplementation of diet had a negative effect on blood HDL concentration.

The effect of essential oils blend, probiotic and flavomycin on performance, gastrointestinal tract (GIT) characteristics, cecal microbial population and blood parameters was studied with 288 day-old chickens, Ross 308 broilers from 1 to 42 days of age in a completely randomized design by 4 treatments, 4 replicates and 18 chickens in each replication. The experimental treatments were: 1) basal diet as control group (without additive), 2) basal diet + 150 mg/kg essential oils blend, 3) basal diet + 200 mg/kg Gallipro® probiotic, and 4) basal diet + 150 mg/kg flavomycin. The results showed that feed intake was lower in the control group than other treatments (P<0.05). In the whole trial period, the weight gain of chickens fed with the diet containing flavomycin was higher than other birds and had a better feed conversion ratio than control birds or fed with the diet contains probiotic (P<0.05). The effect of treatments was not significant on relative weight of internal organs, pH of the GIT digesta and Lactobacillus and Escherichia coli population in the ceca. The relative weight of the breast was greater in chickens fed with flavomycin than control group or birds that received essential oils blend (P<0.05). There was no difference between treatments in terms of plasma cholesterol, glucose and triglyceride concentrations, but HDL concentration was lower in the plasma of birds receiving flavomycin compared to other treatments (P<0.05). Based on the results of this study, adding essential oils blend to the diet improved performance and can be used as a growth promoter instead of flavomycin in broilers diet.

The current study was conducted to determine the effectof feed form (mash, pellet and extrude) on energy and protein efficiency, intestinal morphology and microbiology in broiler chickens. Energy and protein efficiency and European efficiency factor were calculated during the experiment period and jejunum morphology and relative length of intestine, microbial population, volatile fatty acids, viscosity of ileal were determined at 42 days of age. The results have shown that the effect of feed form on jejunum morphology (crypt depth (CD), serosa thickness, villous height (VH) and villous width (VW), VH:CD, length and relative length of intestine, microbial population (spore former bacteria, lactobacilli,colibacilli, total aerobic bacteria) of ileal digesta was not significant (P>0.05). The values of viscosity and volatile fatty acids (butyric, isobutyric, valeric, isovaleric) of ileal digesta was higher and values of pH, ascetic acid was lower in mash diet form in comparison to pellet and extrude diet form (P<0.05). Energy and protein efficiency and European efficiency factor were higher in extrudes diet form in comparison to mash and pellet feed forms in total experiment period (P<0.05). Our findings have shown that that extrusion and pellet feed forms had positive results on volatile fatty acid profile, intestinal contents’ viscosity, energy and protein efficiency and European efficiency factor in comparison to mash feed form in broiler chickens.

In ruminants, dietary manipulation such as applying feed additive or increasing fermentable carbohydrate in diet, improve rumen fermentation and enhance animal performance. Monensin, as a feed additive, increases propionate production, decreases ammonia production and protein degradation in rumen, this lead to improving energy and protein utilization. In addition, grain processing effects on starch fermentation; this could be increasing availability of energy for ruminal microorganisms. One of these processing methods is cracking barley grain. Since, monensin may be influenced on this processing and starch fermentation pattern, therefore the aim of this study, was evaluated the effects of monensin applied in diet and grain processing (cracked barley grain) on nutrients digestibility and protein metabolism in Mehraban sheep.  In this trial, 24 Mehraban male sheep with an average body weight of 52.98 ± 6.15 kg were used on 2 × 2 factorial experiment in a completely randomized design. Experimental factors were included the effects of monensin (diets containing monensin vs. without monensin) and physical form of barley grain (whole grain vs. cracked grain) as fallowing explanation. Sheep were kept in individual stalls for compatibility to the new environment and experimental conditions for 7 days. Then, were randomly divided into 4 groups (treatments) based on body weight and transferred to metabolic cages to determine the nutrients digestibility and nitrogen retention. The treatments were: Barley grain, Barley grain + monensin, cracked barley grain and cracked barley grains + monensin. Monensin was added to the related treatments in 30 mg per kg of feed intake. Determination of nutrients digestibility was conducted by directly collection of feces (in vivo method) for 14 days (the feces and urine samples were taken at the 7 final days). The experimental diets (40% forage and 60% concentrate) were offered twice in daily at morning (8:00 h) and evening (16:00 h). Urinary nitrogen, allantoin excretion, and chemical composition of feeds and feces (dry matter, organic matter, crude protein, ether extract, crude fiber and nitrogen free extract) were determined. Microbial protein synthesis was estimated by measuring the urinary allantoin excretion. Blood samples were taken on the final day (at 0 and 5 hours after the morning feeding) for determination of plasma glucose and urea concentration.  The results have shown that the physical form of barley grain significantly decreased dry matter and organic matter digestibility (P<0.05). Dry matter and organic matter digestibility in treatments with whole barley grain were 73.82 and 74.94 and in treatments with cracked barley grain were 71.58 and 72.84 percentage, respectively. Other nutrients digestibility (crude protein, ether extract, crude fiber and nitrogen free extract) were not affected by physical form of barley grain. Also, using of monensin and physical form of barley grain had no effect on dry matter and nutrients digestibility. Nitrogen metabolism parameters (nitrogen intake and % nitrogen in feces, urine and retention) were not affected by physical form of barley grain. Since, crude protein percentage in all treatments was equal, and dry matter intake was adjusted based on animal body weight and was in a similar range, therefore the nitrogen intake was similar in all treatments and there was no differences between them. But, % nitrogen retention significantly was increased by monensin using (P<0.05) and its amount were 21.23 and 26.33 (% of N intake) for treatments with and without monensin, respectively. Monensin prevents the ruminal proteolytic bacteria, and decreases ammonia production and deamination of amino acids in rumen. Thus, it prevents the loss of protein in the rumen, which result is increasing nitrogen retention. Allantoin excretion, microbial nitrogen synthesis, efficiency of microbial nitrogen and urinary urea were similar in the treatments with whole barley grains and cracked barley grains and there were no significant differences between them. Using of monensin significantly decreased allantoin excretion (P<0.05) and its value were 0.32 and 0.23 g/dl in treatments with and without monensin, respectively. Plasma glucose and urea concentrations (at 0 and 5 hours after the morning feeding) were not affected by the physical form of barley grain, monensin and treatments response. Plasma glucose and urea concentrations were 63.52, 67.88, 64.26, 65.48 mg/dl and 17.05, 15.70, 15.74, 14.75 mg/dl for treatments 1, 2, 3 and 4 at 0 hour after morning feeding, respectively. These parameters were 67.50, 66.86, 71.48, 68.06 mg/dl and 17.06, 14.04, 16.94, 14.87 mg/dl at 5 hour after morning feeding, respectively. Generally, nutrients digestibility, nitrogen retention and microbial nitrogen synthesis were not increased by physical form of barley grain. But, increased nitrogen was found by monensin in the sheep.

The effect of diet with different protein quality andsupplemented with crystalline amino acids on performance, immune response, enzyme activity in the intestinal tissue and litter characteristics, using 576 Ross 308 (mixed sex) broiler chickens,in a 2 × 4 factorial experiment with two experimental diets (high and low protein quality) and four levels of crystalline amino acids (recommended levels, without supplemented crystalline amino acids, 10 and 15% higher than the recommended levels)in a completely randomized design with eight treatments, six replicates and 12 chicks per replicate was investigated.The results of this study showed that, adding crystalline amino acids at levels of 10 and 15% higher than the recommended level to diets containing canola meal and wheat (as low quality protein source) caused an increase in performance (P<0.0001), the number of heterophile and heterophile to lymphocyte ratio (P<0.001) and decreased the number of lymphocyte (P<0.01). The treatments with crystalline amino acids hadn’t significant effect on the enzyme activity aminopeptidase and specific activity of the enzyme in jejunum. Also, adding crystalline amino acids at levels of 10 and 15% higher than the recommended level ina low-quality diet were not significantly affected dry matter, nitrogen and ammonia nitrogen in the litter. According to these results, the use ofcrystalline amino acids higher than the recommended levels in the diets with high quality (as maize-soybean meal) has no effect on the performance of broiler chickens and is not recommended.

The purpose of this research was to evaluate the effects of the feed form on characteristics of litter, quality characteristics of foot and breast and tibia bone indices in broilers. A total of 936 broilers (Ross 308) were randomly assigned to 3 treatments (mash, pellet and extrude) with 12 replicates and 26 day-old chicks in each pen that were reared for 6 weeks. Litter quality (PH, Moisture, Total volatile nitrogen (TVN) and nitrogen retention) values, the counts of the microbial populations (bacterial and fungi), foot and carcass lesions (lameness, footpad lesions, hock burns and breast blisters), calcium and phosphorus content of tibia bone and tibia bone characteristics (length, diameter, weight, weight percent, strength of fragility) were determined at 42 days of age and mortality was recorded daily.
The results have shown that the greater percentage of the moisture, TVN, nitrogen and the lower counts of the spore bacteria and fungi of litter were found by extrude diet form. There is no significant difference on footpad dermatitis, breast blister, calcium and phosphorus of bone and tibia bone characteristics, but the higher rate of hock burns, lameness and percentage of the mortality were observed by pellet and extrude diet form compared with mash diet form in broiler chicken. So pellet and extrude diet form have shown negative effects on values of the moisture, TVN, nitrogen of litter and percentage of mortality and increased incidence of hock burn and lameness in broilers compared with mash diet form.

The effect of different sources of insoluble fiber on performance, gastrointestinal tract (GIT) traits and cecal microbial population was studied with 320 day-old chickens, Ross 308 broilers from 1 to 24 days of age in a completely randomized design by 4 treatments, 4 replicates, and 20 chickens in each replication. Experimental treatments including: control (corn-soybean meal)which was diluted by 3% of treated wheat straw, sunflower and soy hulls. Feed intake was not affected by treatments from 1 to 24 days of age. Body weight gain increasedin treated wheat straw group relative to soy hull group. In addition, feed conversion was improved in broiler fedding by treated wheat straw compared to sunflower and soy hulls (P

In order to evaluate the effect of barley grain processing and dietary nitrogen source on digestibility, microbial protein synthesis and nitrogen retention in sheep, an experiment was conducted as 2×2 factorial under a completely randomized design. The experimental diets included 1) whole barley grain urea, 2) whole barley grain soybean meal, 3) cracked barley grain urea and 4) cracked barley grain soybean meal. During the digestibility experiment, total urine of sheep was collected, and blood samples were taken at 1 and 7 hours after morning feeding at the last day. Results showed that barley grain processing decreased dry matter digestibility (from 73.82 to 71.58 percent) and organic matter digestibility (from 74.94 to 72.84 percent) of diet (P

This experiment was conducted to consider of sunflower meal (SFM) levels and protease enzyme on performance, egg quality traits and intestinal morphology of laying hens from 78 to 86 weeks of age. In total, one hundred and twenty white Bovans laying hens were used in 6 treatments, 5 replicates and 4 hens in each in a factorial arrangement 3×2 by completely randomized design (CRD). The experimental treatments contain 3 levels (0, 6.78 and 13.56% SFM) and 2 levels of protease enzyme (0 and 200 g/ton). Results have shown that second level of SFM (6.78%) in the diet increased egg production than control treatment (P

In order to evaluate the effect of polyunsaturated fatty acids on ascites incidence using this experiment was conducted 136 male one day (chicken Ross 308) in a completely randomized design with 2 treatments and 4 replication and 17 chickens in each replicate. Treatments includes: diet contain 4 % soybean oil (n3:n6:0.112) and diet include 5.5% poultry oil (n3:n6:0.201). Birds were raised up to 48 days of age and exposed to a cool temperature (15±1°C) from day 21 thereafter. Blood samples (2 mL) were obtained from the wing vein at 21 and 48 days of age. At 21 and 48 days of age, 2 birds in each replication were slaughtered and the hearts, Liver and pulmonary artery were removed and dissected to measure right ventricular hypertrophy. The results have shown diet with 5.5% poultry oil significantly decreased blood viscosity (P<0.05). However concentration of thyroxin, rectal temperature and glutamate dehydrogenase activity were also significantly increased in this treatment (P<0.05). Malondialdehyde as an oxidative stress index significantly increased by diet contain 5.5% poultry oil. Based on results of this research it can be concluded that high ratio of n3:n6 in poultry oil couldn’t decrease ascites mortality as compare with soybean oil.

This experiment was conducted to examine the effect of different levels of protein (13 and 15%) and methionine (0.25, 0.30 and 0.35%) on performance and some egg indices in the late laying period of layer hens. Ninety six leghorn 80 weeks W-36 layers were used as a 2×3 factorial arrangement based on the completely randomized design. The results have shown that as methionine level was increased, the production percentage and egg weight were increased (P<0.05). Different levels of protein had no significant (P>0.05) effect on the production percentage and egg weight. Treatment effect on the production percentage and egg weight was significant (P<0.05), as birds fed diet containing 15% protein and 0.35% methionine had the highest production percentage and egg weight. Experimental treatments had no significant (P>0.05) effect on other parametes (cracked and soft eggs sell, yolk and albumen indices, egg area, egg weight to area ratio, yolk color, haugh unit, egg content and egg shap index). It can be concluded that the best levels of protein and methionine for egg production in the late laying period of laying hens are 15 and 0.35%, respectively.

An experiment was conducted with 855 fertilized eggs in 8 treatments (injection in 5th day of incubation) and 11 treatments (injection in 17th day of incubation) with 3 replicates of 15 eggs each. Treatments included first control (no injection)، second control (injection of 0. 5 ml. of sodium chloride); in 5th day، experimental treatments included 30 and 45 mg. silver nanoparticles، and 100 mg. of thyme and savoury. In 17th day treatments included 30، 45، and 60 mg. silver nanoparticles، and 100، 150، and 175 mg. of thyme and savoury extracts. Injection in 5th day indicated that the bursa weight reached its maximum in treatments 75 and 100 mg. of thyme، and 75 mg. of savoury، and in treatments with 30 and 45 mg. of silver nanoparticles had a minimum level (P).

This present study was conducted to evaluate the effects of dietary inclusion of 4, 8 and 12 g kg-1 phytogenic feed additives mixture on performance, egg quality, ovary parameters, serum biochemical parameters and yolk trimethylamine level in laying hens. The results of experiment have shown that egg weight was increased by supplementation of 12 g kg-1 feed additive whereas egg production, feed intake and feed conversion ratio (FCR) were not significantly affected. There were no significant differences in egg quality parameters by supplementation of phytogenic feed additive, whereas yolk trimethylamine level was decreased as the feed additive level increased. The sensory evaluation parameters did not differ significantly. No significant differences were found in serum cholesterol and triglyceride levels between the treatments but low- and high-density lipoprotein were significantly increased. Number of small follicles and ovary weight were significantly increased by supplementation of 12 g kg-1 feed additive. Overall, dietary supplementation of polyherbal additive increased egg weigh, improved ovary characteristics and declined yolk trimethylamine level.

A study was conducted to evaluate the effects of blood pressure medications on index of liver damage in Ascites Incidence in broilers. A completely randomized experimental design with a 2×3 factorial arrangement (sex and feed additive), with 3 replicates of 12 birds, with 216 (108 male and 108 female) one-day-old (Ross 308) was applied. Feed additive includes control (without feed additive) levothyroxine and atenolol at level of 45 ppm in the basal diet after 21 days of age. Albumin and total protein of serum and ascetic fluid, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) enzymes acivity of serum were determined in 42 and 49 days of age. In 42 days of age 2 birds from each replicate and in 49 days of age all birds slaughtered and relative weight of spleen, liver and heart measured (ratio body weight). Total ascites mortality and ascites morbidity (the ratio of right ventricular weight to total ventricular weight) in 42 and 48 days of age. Levothyroxine in diet increased the ALT an AST activity in contrast reduced albumin and total protein of serum. Relative weight of spleen decreased in response to levothyroxine in diet but relative weight of heart and liver increased. Ascites mortality and ascites morbidity decreased in response to atenolol in diet. The results of this experiment indicated Levothyroxine could be a replacement of cool temperature in rearing period for ascites incidence in broilers.

A study was carried out to investigate the effects of organic acid mixture as well as two methionine supplements on performance, carcass characteristics and weight of gastrointestinal tract in broiler chickens. Six hundred unsexed day-old Ross 308 broiler chicks were utilized in a factorial arrangement of treatments (3×2) based on Completely Randomized Design (CRD) of 4 replicates of 25 chicks each. a Chicks were placed in floor pens (1.2 ×2 m2). Experimental diets consisted of three levels of organic acid mixture consisting of formic, lactic, malic, citric, tartaric and ortho-phosphoric acid (under the trademark Orgacid) (0, 0.5, and 1%) and two sources of methionine supplement (DL-methionine and liquid methionine hydroxy analogue (Alimet). The experiment was carried out in two periods. Levels of 0.5 and 1% of organic acids mixtures increased body weight and improved feed conversion ratio (P<0.05) during all the periods. During the grower period Alimet increased carcass weight as compared with DL-methionine. Levels of 1% of organic acid mixtures increase carcass weight as compared with other levels in starter (P<0.05). Also in this period breast weight was significantly increased by 0.5 and 1 % of organic acids mixture compared with that at 0% level (P<0.05). Abdominal fat was significantly increased by 1% organic acid mixture compared with that of 0.5% at 21 days of age. The use of organic acid at 1% level resulted in decreased in cecum weight at 21 days of age compared with that at the level of 0% (P<0.05). Intestinal length (by 0.5 and 1 % of organic acid mixture) significantly increased as compared with those at 0% level (P<0.05). Application of organic acid in general, increased carcass weight, breast weight, intestine length while decreasing weight of cecum at 21 days of age. Alimet increased carcass weight as compared with DL-methionine.