broiler chicks

Glutamine represents approximately 30-35% of the total amount of nitrogen in the blood derived from amino acids. The role of glutamine as a nitrogen shuttle helps to protect against the toxic effects of high levels of ammonia in the blood. In addition, glutamine has vital and specific metabolic functions as a vehicle for carbon exchange between tissues, as a fuel for rapid cell division, and as a precursor of many naturally active molecules. It's a great example of how amino acids are used for different purposes in the metabolism and the immune system of the body. Glutamine, a conditionally essential amino acid, seems to be a key nutrient for the gut, as it may be a prominent source of vitality for the enterocytes. Glutamine appears to trigger an increase in the level of intestinal secretory immunoglobulin A, which is essential for mucosal defense. The investigation showed that the use of amino acid supplements in broiler diets improves the performance and the carcass characteristics. Glutamine is one of the most abundant amino acids in blood plasma and is involved in the building of muscle, and tissue, and gaining body weight. Researchers found that adding 10 g of L-glutamine per kg of food increased the weight gain and serum immunoglobulin A and G concentrations in broiler chickens. Therefore, an experiment was carried out in broiler chickens over 42 days of production to determine the effect of L-glutamine on broiler growth, carcass quality, and certain blood parameters.

The experiment was conducted using 300 one-day-old male Ross 308 broiler chickens in a completely randomized design with five treatments and five replicates from the age of 1 to 42 days. The experimental treatments included were: the addition of zero, 0.25, 0.5, 0.75, and 1% of L-glutamine in corn-soybean meal-based diets supplemented with dietary fat. During the experimental period, average daily feed intake (DFI), body weight gain (BWG), and feed conversion ratio (FCR) were measured. At the end of the experiment, two birds were selected from each replicate and slaughtered after weighing, and the weight of the internal organs (thigh, breast, heart, liver, gizzard, fat pad, pancreas, bursa, spleen, and thymus) was measured. Blood samples were collected from two birds per replicate to determine the number of white blood cells (WBC), and heterophile to lymphocyte ratio (H/L). Blood samples were taken from the jugular vein in tubes without anticoagulant and then centrifuged (2000×g for 10 min) to obtain a serum. On the 42nd day of rearing, serum cholesterol (total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL)) and triglycerides were determined by calorimetric examination.

Weight gain during the initial and growth periods was affected by L-glutamine supplementation (P<0.05). Despite higher feed intake for L-glutamine-supplemented diets during the initial period, this effect was significant only during the growth period (P<0.05). FCR and relative weight of internal organs, except liver weight, were not significantly different from the control group in the L-glutamine-supplemented chickens. The addition of 0.5% L-glutamine supplementation reduced cholesterol and triglyceride content and increased HDL in the blood of broilers (P<0.05). The H/L ratio in chickens that consumed L-glutamine was significantly lower than in the control group (P<0.05). L-glutamine has been reported to increase the activity of the intestinal enzyme Na-K ATPase, thereby indirectly increasing the absorption capacity of nutrients such as glucose and amino acids in the intestine. Researchers reported that L-glutamine increases the performance and feed intake of chickens by improving intestinal function and increasing digestibility. Expanding the villi of the small intestine can increase digestion and feed intake by increasing nutrient absorption and thus improving chicken performance. Improving the morphology of the digestive system is one of the possible mechanisms of the positive effect of L-glutamine on improving weight. Since glutamine stimulates anabolic conditions in the body and increases the amount of protein synthesis, therefore, along with muscle growth, it can increase the final body weight. Avian health is directly related to the immune system, and birds with adequate immune systems grow better. The majority of essential amino acids are recognized as critical resources for cytokine production and immune function.

Results from this study indicate that 0.5% dietary glutamine supplementation improved growth performance and had a positive effect on lipid metabolism-related blood parameters.

This study was conducted to investigate the effects of sour tea powder on growth performance and immune responses of broiler chicks under conditions challenge with ascites. 400 broiler chicks were studied in arrangement of 4 experimental diets including: Treatment 1: Positive control group (without induction of ascites and without powder), treatment 2: Negative control group (induction of ascites without powder), Treatments 3 and 4) 1% and 2% sour tea powder groups with ascites induction, and inclusion of 1% and 2% tea powder. This study was conducted for 42 days and the induction of ascite was started from day 8. This study was conducted in form of a completely randomized design with 4 treatments and 5 replications. Performance parameters (body weight, feed intake and feed conversion ratio), immune responses against SRBC, weight of immune organs (spleen, thymus and bursa) and heart indexes were investigated. The results showed that the induction of ascites decreased body weight and increased feed conversion ratio in finisher period. The induction of ascites also decreased relative weight of heart indexes, immune organs and antibody titer (p<0.05). Dietary inclusion of 2% plant powder increased growth performance in finisher and total periods. It also improved relative weight of immune organs and antibody titer against SRBC. In conclusion, adding 2% Sour tea powder into diet is suggested to improve immune responses and growth performance under ascites condition.

The use of agricultural and food industry by-products in animal feed leads to a reduction in breeding costs. In addition application of agricultural waste in poultry feed also reduces the environmentally harmful effects. One of these by-products is pistachio green peel, which is produced in food industries. Common pistachio (common pistachio in the market) with the scientific name Pistacia vera is a plant of the genus Anacardiaceae. Iran is the world's largest pistachio producer with 58% of the world's pistachio production. Research has shown that about four hundred thousand tons of pistachio by-products are produced annually in Iran and large volumes in the harvest season and high humidity of these products cause environmental pollution and pistachio orchards. Pistachio green peel has a parenchymal and fibrous structure and contains water, sugars, proteins, fats, minerals, vitamins, color compounds and terpenes. Green pistachio skin contains 4425.45 Kcal/kg of gross energy, 32.64% of dry matter, 11.24% of crude protein, 15.38% of crude fiber, 13.13% of ash, 5.79% of ether extract, 1.08 of calcium, 0.11% of phosphorus, 0.31% of magnesium, 4.44% of potassium. The concentrations of iron, manganese, copper and zinc in pistachio green peel are 660.68, 23.6, 16.23 and 5.27 mg/kg, respectively. There are significant amounts of alpha-pinene, alpha-terpinolene, flavonoids and phenolic compounds. Food sources rich in phenolic compounds have a set of physiological properties including antioxidant, antimicrobial, anti-mutagenicity, lipoprotein oxidation inhibitor and have platelet aggregation, anti-inflammatory activity  and strengthen the immune response. The use of pistachio green peel extract improved the growth performance of broiler chickens, blood lipids and abdominal fat. The use of pistachio green skin extract in the diet of broiler infected with Staphylococcus aureus improved growth performance, increased antibody titer against sheep erythrocytes, decreased blood lipids and microbial population of the gastrointestinal tract of broilers. Therefore, the aim of this research was to investigate the effect of Green Pistacia of kallequchi and it’s processed with urea on growth performance, blood indices, immune response and jejunum morphology of broiler chickens.

A total of 280 male broilers were randomly distributed in 28 experimental units including 7 treatments, 4 replicates and 10 chicks each. The experimental diets consisted of the levels of 0, 1.5, 3, and 5% of the raw and processed green hull of kallequchi pistachio. The broilers were fed with three dietary programs including starter (1-10 days), grower (11-24 days), and finisher (25-42 days). At the end of each period, the body weight gain and feed consumption were recorded and the feed conversion ratio was calculated. Two birds of each replicate were slaughtered and their blood was gathered to analyze the biochemical blood indices at 42 days of age. The data were analyzed with SAS software and the mean was compared with the Tukey test at 0.05.

The addition of green hull of pistachio and its processed to diets cause a decrease in the feed conversion ratio during the starter and the whole period of the experiment (P≤0.05). In the starter period, adding 3% of the green hull of the pistachio increased the body weight gain compared to the control (P <0.05). The pistachio green hull increased total antibody and immunoglobulin G antibody titer against sheep red blood cells compared to control (P≤0.05). Experimental diets decreased serum cholesterol and LDL concentrations compare to control (P≤0.05). The green hull of kallequchi pistachio and its processed increased the villus height and decreased villus width and the ratio of height to crypt depth compared to the control (P≤0.05). Different levels of kallequchi pistachio green hull and its processed increased relative weight of the breast, heart, burs fabricius and decreased abdominal fat compared to control (P≤0.05). The same findings were reported by researchers that pistachio green hull extract decreased blood lipids and increased the immune response of broiler chickens (Yousefi et al., 2018; Hosseini Vashan et al., 2020).

It is concluded that adding green hull of kallequchi pistachio up to 5% into broiler diets may improve growth performance, however, the addition of 3% could reduce cholesterol, FCR and improve the immune response of broiler chickens.

This study was conducted to investigate the synbiotic and probiotic effects of two dietary supplements produced by Iran Scientific and Industrial Research Organization on growth performance and immune responses of broiler chicks challenged with Salmonella Typhimurium. 360 Ross 308 broiler chicks were studied in 6 treatments with 6 replications and 10 broiler chicks per replicate. This study was conducted in a factorial arrangement based on completely randomized design with 2 factors of challenge (challenge and non-challenge) and additives (lack of additive, 0.2 g/kg dietary supplement). Probiotic was containing Bacillus subtilis, B. licheniformis, and Saccharomyces cerevisiae. Synbiotic was contained same bacteria and fructans. Growth performance, including average daily feed intake (ADFI), average daily gain (ADG), feed conversion ratio (FCR), production index, and immunoglobulins G and M were investigated. The results showed that challenge with Salmonella decreased ADFI, ADG and production index compared to non-challenged broiler chicks (P<0.001). Challenge decreased the levels of immunoglobulins G and M compared to non-challenged broiler chicks (P<0.001). However, the results showed that dietary inclusion of supplements increased production index, ADFI and ADG and immunity compared to non-treated broiler chicks (P<0.001). In conclusion, the use of 0.2 g/kg of dietary supplements produced by this organization improves growth performance and immune responses against infectious challenges in broiler chicks due to their probiotic and synbiotic properties.

Effect of Basil powder and extract on yield and carcass characteristics, relative expression of heat shock protein gene (HSP70) and someblood parameters of broiler chickens under heat stress using 160 Ross 308 one-day-old broiler chicks in a completely randomized designwith 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 Basilpowder (per kg of grain), 5- The use of Basil extract (1 ml/liter water). Feed intake, body weight gain, feed conversion ratio, carcasscharacteristics, blood parameters and relative expression of HSP70 gene in blood were measured. The effects of treatments on bloodparameters and carcass characteristics were not significant. Relative expression of the HSP70 gene in the blood was significantly reduced inall treatments compared to the control (P<0.05). Based on the results, basil powder and extract reduce the negative effects of heat stress inbroilers, so their use in broiler diets is recommended to prevent heat stress.

In this research total of 288 one- day old Ross 308 broiler chickens were used in a completely randomized design with 6 treatments and four replications for 5 weeks. The experimental treatments included 1) Basal diet without additive and normal temperature conditions (negative control) 2) Basal diet without additive and heat stress conditions (positive control) 3) Basal diet with 0.18 mg/kg sodium selenite and normal temperature conditions 4) Basal diet with 0.18 mg/kg sodium selenite and heat stress conditions 5) Basal diet with 0.18 mg/kg nano-selenium and normal temperature conditions and 6) Basal diet with 0.18 mg/kg nano-selenium and heat stress conditions. The results showed that in normal temperature conditions, nano-selenium caused decrease in feed intake in comparison to sodium selenite however in heat stress conditions, both nano-selenium and sodium selenite increased feed intake when compared with control treatment (P<0.01). Also, the results of feed conversion ratio showed that the highest and lowest feed conversion ratios in all rearing periods were related to the control in heat stress conditions and nano-selenium under normal temperature conditions, respectively (P<0.01). The highest and lowest blood serum malondialdehyde, aspartate transaminase and alanine transaminase, concentrations were observed in control treatment under heat stress conditions and treatment containing nano-selenium in normal temperature conditions, respectively. Generally the results of the present study showed that the utilization of nano-selenium in heat stress conditions in diet of broiler chickens improved feed conversion ratio, increased growth and increased cellular oxidation inhibitory enzymes.

This study was conducted to investigate the effects of toxin binders and prebiotics on growth performance, intestinal microbial population, stress andantioxidant indexes of broiler chicks fed diets contaminated with aflatoxin B1. In this study, 600 1-d-old mixed broiler chicks (Ross 308) wereinvestigated in 10 treatments with 6 replications and 10 chicks per replication. Experimental treatments included: Negative controls un-supplementedand supplemented with ASRI1 and ASRI2 toxin binders and prebiotic and positive groups un-supplemented and supplemented with ASRI1 andASRI2 toxin binders and prebiotic, ASRI1 +prebiotic and ASRI2 +prebiotic. Growth performance, stress indexes of heterophile, lymphocyte,bacterial population and stress indexes of super oxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA) wereinvestigated. Dietary inclusion of aflatoxin into diet increased heterophile, heterophile:lymphocyte ratio and decreased lymphocyte (P<0.05), but toxinbinders and prebiotic alleviated effects of aflatoxin on heterophile and lymphpocyte. Thepopulation of E. coli and lactobacilli were significantlyhigher and lower in positive control compared to negative control (P < 0.05). The results also showed that the serum concentrations of antioxidantenzymes were significantly lower in negative control compared to positive control (P < 0.05). In sum, aflatoxin showed negative effects on growthperformance, intestinal microbial populations, stress and antioxidant indexes but toxin binders and prebiotic decreased its negative effects andinclusion of ASRI1(3kg/ton) was better than other toxin binders.

The current study aimed to investigate the effects of adding probiotic and encapsulated thyme essential oil (TEO) on growth performance and immuneresponses of broiler chicks by multi attribute decision making (MADM). In the current study, 420 broiler chicks were allocated into 7 experimentalgroups with 6 replication and 10 broiler chicks per replication for 42 days. The experimental treatments were included 1) diet lack of TEO andprobiotic (control), 2) diet containing 100 mg probiotic, 3) diet containing 100 mg TEO, 4) diet containing 200 mg probiotic, 5) diet containing 200mg TEO, 6) diet containing 100 mg probiotic+100 mg TEO, and 7) diet containing 200 mg TEO+ 200 mg probiotic. Growth performance andhumoral immune responses were investigated. Index weights for weight gain, feed conversion ratio, production index were 0.2, 0.15 and 0.25,respectively and index weight of 0.1 was considered for other parameters. Coefficients for control, probiotic 100, TEO 100, probiotic 200, TEO 200,probiotic 100 + TEO 100 and probiotic 200 + TEO 200 were 0.0476, 0.126, 0.198, 0.315, 0.427, 0.727 and 0.956, respectively. Thus, adding 100 mgprobiotic and 100 mg TEO into diet increased immune response and growth performance. Based on obtained results, it is suggested that dietaryinclusion of 100 mg TEO + 100 mg probiotic in diet of broiler chicks has a potential to improve immune response and growth performance.

The central melanocortin system appears to be an important mediator of the actions of both leptin and insulin, which are key elements in the control of energy balance. Proopiomelanocortin (POMC) is a complex precursor protein that is proteolytically cleaved to a variety of biologically active and important neuroendocrine peptides. The POMC gene is expressed mainly in the anterior and intermediate lobes of the pituitary and in the arcuate nucleus of the hypothalamus, and at a lower level also in a wide variety of peripheral tissues and of brain regions in mammals. It produces many biologically active peptides via a series of enzymatic steps in tissue-specific manners, which have important roles in the regulation of appetite, sexual behavior, the movement of melanin produced from melanocytes in skin and the production of endogenous opioid peptides with widespread actions in the brain. In chicken, the POMC gene consisted of three exons and two introns and its protein has 251 amino acid residues with nine proteolytic cleavage sites, suggesting that it could be processed to give rise to all members of the melanocortin family, including adrenocorticotropic hormone and alpha-, beta- and gamma-melanocyte-stimulating hormones, as well as the other POMC-derived peptides.
Considerable evidence has been collected indicating that POMC mutations are associated with obesity.

Blood samples were collected in EDTA vials from one hundred Ross and sixty Cobb broiler chicks, stored at -20 and their DNA was extracted using the modified salting-out chloroform method. Polymerase chain reaction (PCR) was carried out by specific primer pairs to amplify a 444bp fragment from a part of exon two of the Pro-Opiomelanocortin gene. The pattern of all samples was determined through single stranded conformation polymorphism (SSCP) analyses by Acrylamide gel using silver nitrate staining.
The associations between polymorphisms (patterns) and the growth traits (live and carcass weight, and the weight of breast, thigh, back and neck, wings, liver, heart, bursa of Fabricius, pancreas, paraventricular, gizzard and spleen) were evaluated using the GLM procedure of the SAS software.

The extraction or genomic DNA and amplification of 444bp fragment of Pro-Opiomelanocortin gene were successfully done and it was polymorph in both strains. Two different patterns were found in Ross strain, E and F patterns with the frequencies of 0.56 and 0.44, respectively. Four different patterns were found in Cobb strain, A, B, C and D patterns with the frequencies of 0.63, 0.09, 0.14 and 0.14, respectively. There was no significant association between the patterns and the growth traits. In Ross strain, the effect of genotype (pattern) tend o be significant for carcass weight (p value = 0.054) and the chickens with F pattern have more carcass weight than those with pattern E. In Cobb strain, chickens with B pattern tend to have better slaughter yields compared to other patterns. Our results revealed that Cobb strain has more diversity in the studied fragment of POMC gene than Ross strain.

Energy homeostasis and body weight (BW) are regulated by coordinated actions of multiple genes. For significant economically traits, improvements in BW can be achieved through mass selection whereas feed conversion is relatively more difficult to improve. Gene polymorphisms can be used for improvement of the production traits by genetic selection, if the allelic association with the traits be determined. The variable associations of the identified polymorphisms may be a result of the differences in the population characteristics,
sex, or both, indicating that the selection criteria may influence the production trait associations. This should be taken into consideration while selecting for the desired production traits. Additional studies are required to expand the genetic and physiological aspects involved in feed intake, digestion, and metabolism. The genomic diversity also has important implications in the evolutionary dynamics of species. Investigations of polymorphisms are useful for better understanding of the gene function, and those associated with commercially significant production traits have a potential for usage as molecular markers for selection programs. In summary, the identified polymorphisms and their associations with the traits of economic importance in the present study provides greater insight into the role POMC gene involved in energy balance in poultry and points toward the
potential application of the findings for the enhancement of production traits by marker assisted selection.

The current study was carried out to investigate the effect of native fungal and bacterial recombinant phytase enzymes produced in lab with commercial sample on performance, growth parameters, Ca and P using 200 day-old Ross 308 broiler chicken which assigned in a completely randomized design to five treatments with four replicates. The experimental treatments included T1: control diet (without enzyme), T2: control diet+commercial phystase enzyme of Nataphus, T3: control diet+Bacillus subtilis enzyme, T4: control diet + E. coli enzyme and T5: control diet+Aspergillus niger enzyme. The results of this study showed that the addition of enzyme to diets decreased feed intake in grower, finishing and total period (P<0.05). Feed conversion ratio was improved due to the addition of phytase to diets in all periods (P<0.05). Time and weight at inflation point showed a significant difference between the experimental treatments and control group (P<0.05). The highest concentration of blood phosphorus at 21 days of age was observed in the group consumed commercial enzyme (P<0.05). But the amount of phosphorus and bone ash content significantly affected by the enzymes consumed (P<0.05). Overall, the addition of phytase enzyme to diets improved the feed conversion ratio and decreased feed intake compared to control group, and no significant difference was observed between commercial enzymes and enzymes produced.

The aim of this experimentwas to investiagatethe effects of different levels of valine on performance, carcass traits and quality and insulin like growth factor-1(IGF-1) and insulin genes expression in male Ross 308 broiler ckickens. Present study performed using 250 one day male broiler chicks Ross 308 in completiy randomized design including 25 pen, 5 treatments and 5 replicates each (10 chicks in each replicate) with 5 levels of valine (100, 105, 110, 115, 120 percent of Ross starin requirments). At day 42 of age, one chick from each replicate slaughtered to determine the carcass traits, meat quality, serum IGF-1 and insulin and IGF-1 genes expressions. The improved body weight gain and decreased feed conversion ratio during starter, grower and finisher periods were observed by consumption of 110% valine level. Consumption of 110% valine caused the increased carcass, breast and thigh and lowered abdominal fat at 42 days of age. The IGF-1 and insulin genes expression of breast muscle and liver increased by 115% valine. At day 42 of age, consumption of 110% valine improved the protein, dry matter, crude fat and ash content of meat. In conclusion, consumption of 10% higher than Ross valine requirements increases the IGF-I and Insuline genes expressions through up-reguletion of mTOR and promotion of S6k1 phosphorylation signaling mRNA translettion and protein synthesis and hence improves the performance and carcass quality and decreases the abdominal fat in Ross 308 broiler chickens.

This research was conducted to evaluate the effects of different levels of nucleotide supplementation on growth performance and immune responses of broiler chickens. An experiment was conducted as a completely randomized design using 300 day-old male chicks, were divided into five treatments with five replicates and 12 chicks in each replicate. The treatments consisted of the basal diet without additives (control), the basal ration + 500 g/ton of probiotic CloSTAT, basal diet + 400, 500 and 600 g/ton enriched nucleotide supplement, respectively. Daily feed intake, daily body weight gain and feed conversion ratio were measured at the end of each period. Humoral and cellular immunities were evaluated by intramuscular injection of sheep red blood cell (SRBC) and intradermal injection of phytohemagglutinin-P (PHA-P) in wing, respectively. The results indicated that all levels of the nucleotide reduced the daily feed intake (89.7, 83.3 and 79.4 vs. 98.2 g, respectively) and improved feed conversion ratio (1.67, 1.62 and 1.62 vs. 1.93, respectively; P<0.05).  On day 28, probiotic CloSTAT and 400 and 500 g/ton of nucleotide had higher levels of total anti-SRBC (5.20, 6.60 and 6.90 vs. 3.20) and IgM (2.60, 3.20 and 2.20 vs. 0.90; P<0.05). On day 35, the treatments of 400 and 500 g/ton nucleotide have higher total anti-SRBC (6.60 and 6.10 vs. 3.80 and 4.50), IgG (3.50 and 3.30 vs. 2.10 and 2.50) and IgM (3.10 and 2.80 vs. 1.70 and 2.00) than the control group and probiotic CloSTAT (P<0.05).  Cell immunity in response to PHA-P injection was not affected by treatment groups (P>0.05). It is concluded that consumption of 400 and 500 g/ton enriched nucleotide supplement in the diet has beneficial effects on performance and immune responses of broiler chicks.

Zinc (Zn) is an essential trace element for poultry nutrition, because of its important role in various biological functions. For decades, the nutritional importance of Zn has been known, but its vital roles in immune modulation and functioning has been arisen (Bonaventura et al. 2015). The forms of Zn in the diet of poultry could be as inorganic form like Zinc oxide (ZnO) and Zinc Sulphate and as organic shapes like Zn acetate (Zhao et al. 2014). A new form of this inorganic salt is zinc oxide nanoparticles (zno nanoparticles) that have produced by nanotechnology (Song et al. 2010). Nanoparticles have larger surface area that allows higher interactions with other molecules, and the larger surface area enhances the bioavailability and the intestinal absorption of these tiny structures (Nel et al. 2009; Tsai et al.  2016). In general, little studies have indicated that the application of nano minerals in broilers production, immune responses is promising. One of the most promising spore forming lactic acid-producing species is Bacillus coagulans (B. coagulans) (Hyronimus et al.  2000). Bacillus coagulans is a safe, unique gram-positive, spore-forming, microaerophilic, lactic acid producing bacillus that does not encode enterotoxin. It possesses a protective, spore-like protein coating, which allows it to resist high temperature and to survive stomach acid and bile salts, reach the small intestine, germinate, and multiply (Hyronimus et al.  2000). It has been demonstrated that supplementation of B. coagulans in chicken feed promotes their growth performance (Hung et al. 2012). Some previous studies reported that probiotics could effectively enhance immune functions of broiler chicks. Kabir et al. (2004) found that broiler chicks fed with probiotic improved antibody titers against sheep red blood cells (SRBC). In addition, researchers have used probiotics in combination with some nanoparticles, such as nano-selenium, to improve the growth performance and immunity in broiler chicks (Saleh, 2014). In addition, another research demonstrated that probiotics decreased intestine pH, hence it increased production of short-chain fatty acids because of the modification of the gut flora with a consecutive increased mineral solubility and absorbability (Gilman and Cashman 2006; Scholz-Ahrens et al. 2007). According to the above evidences, it appears that combination of zno nanoparticles with probiotic probably causes synergism effects between them through their impact on performance. Thus, in the current study, the synergistic effects of zno nanoparticle in combination with a probiotic on the growth performance and immune responses of broilers was studied. Therefore, the aims of current study were to evaluate the effects of B. coagulans and different levels of zno nanoparticles on growth performance, carcass characteristics, and immune responses parameters.

This trial was conducted with 288 male Ross broiler chicks in a completely randomized design with 6 dietary treatments and 4 replicates with 12 birds per replicate. The experimental treatments were included: control diet (100 mg/kg zno), control diet plus 100 mg/kg probiotic, basal diet without zno plus 25 and 50 mg/kg zno nanoparticles with or without probiotic. The basal diet was formulized according to the dietary requirements in accordance with the Ross guidelines. In this experiment the performance parameters (body weight gain, feed intake and feed conversion ratio), humoral immune (antibody titer against sheep red blood cells), carcass parameters (relative weight of carcass, breast, thigh, spleen, liver, pancreas, bursa of Fabricius and the relative weight and length of the duodenum, ileum and cecum) and intestinal and gizzard pH were measured. On day 42 of experiment, two birds from each replicate were selected, then weighed, were slaughtered and carcass parameters were weighed using a digital scale and their relative weight to body weight were calculated. The length of the various parts of the small intestine was measured after the separation from the mesenteric with the ruler. The collected data were compared using SAS software version 9.1.

Using zno nanoparticles with probiotic improved body weight gain and feed conversion ratio of broiler chicks (P<0.05). It has been demonstrated that supplementation of B. coagulans in chicken feed promotes their growth performance (Hung et al.  2012). In other study, broiler chicks fed multi-strain probiotic diets have greater body weight gain and lower feed conversion ratio than those fed control diet (Zhang and Kim 2014). Jawad et al. (2016) were indicated that supplementation with probiotic improved body weight gain and feed conversion ratio. The possible mechanism for this improvement is that probiotic exert useful effect via retention of beneficial bacterial population in the digestive tract and improvement of feed digestion and absorption. In the present study, treatments had no significant effect on relative weight of carcass, breast, spleen, bursa of Fabricius, pancreas, and liver (P>0.05). The relative weight of liver and thighs in broiler fed with combination of zno nanoparticles and probiotic were lower and higher than control group, respectively (P<0.05). It was reported that using probiotic (Primalac) to the diet of broilers had no effect on growth performance, carcass quality, carcass weight, carcass traits, breast, heart, abdominal fat, spleen, and bursa of Fabricius (Shirmohammad et al. 2015). In addition, treatments had no significant effect on relative weight and length of different parts of small intestine (duodenum, ileum, and cecum) and pH of gizzard and cecum of broilers (P>0.05). The antibody titer against SRBC in chickens fed with 50 mg/kg of zno nanoparticles with or without probiotic were significantly more than the control group. In other study, the variation in Zn levels affected the antibody titers against SRBC inoculation and the amounts of humoral immune response. The highest antibody titers in broiler were observed at 80 mg/kg level compared with lower levels (Sunder et al. 2008). Changes in Zn status of body influenced the T cell functions and the balance between the different T helper cell subsets (Bonaventura et al. 2015).

In conclusion, the results showed that the use of 50 mg/kg of zinc oxide nanoparticle with probiotic (Bacillus coagulans) caused an improvement in growth performance, some carcass characteristics, and immune responses of broiler chickens. In addition, we concluded that substitution of the mineral form (zinc oxide) with zinc oxide nanoparticle in broiler diet did not affect the broiler performance.

This study was carried out to investigate the effects of Savory essential oil and Flavomycin on performance, some carcass traits, immune response and hematology of broiler chickens. In this research, four houndered Ross 308 male chicks were used in a completely randomized design with 5 treatments and 4 replicates and 20 broiler chicks per experimental unit. Experimental treatments consisted of control group (without any additive in diet), diet containing 0.6% of flavomycin, and dietes containing 200, 400 and 600 mg savory essential oil per Kg diet, respectively. The results showed that the addition of savory essential oil significantly improved feed intake and feed conversion ratio in comparison with flavomycin in first and fifth weeks of age and in the first week significantly improved weight gain compared with the negative control group (p<0.05). The effect of savory essential oil and flavomycin on body weight gain and feed conversion ratio in broiler chicks was not significant in the whole period. There was a significant difference between the experimental groups in terms of water intake during the whole period of breeding, and in this regard, chicks fed 400 ppm of savory essential oil had the least water intake (p<0.05). Consumption of savory essential oil and flavomycin had no significant effect on carcass traits, blood parameters, immunity statue and quality of breast meat of broiler chicks (p>0.05). Based on the results of this study, savory essential oil and flavomycin had not positive impact on productive performance, immune response and carcass quality in broiler chicks.

Polyphenols content in the grape seed are considered as potent aromatase inhibitors. In this study, the grape seed extract was injected into the egg as an anti-aromatase and its effects on sex differentiation and gonadal structure in broiler chicks were investigated. A total of seven hundred eggs from Ross 308 were divided into 7 experiment groups.  Treatments including: injection of 3(GSE3) and 4(GSE4) milligrams of grape seed extract and zinc, 3 (NGSE3) and 4(NGSE4) milligrams of nanoparticle of grape seed extract and zinc, 0.05 mg tamoxifen and zinc (TOM+Zn), 0.5 ml normal saline (PC) and control with no injection (NC). Injection was performed on day 5 of incubation from the narrow side of egg. After hatch, chickens were reared for 5 weeks. Results showed that compared to controls, injection of grape seed extract caused significant increase in percentage of male chick(P<0.05). No significant differences were found in day old chick weights (P>0.05). Feed intake, body weight, body weight gain and feed conversion ratio appeared with no significant differences (P>0.05). The study of gonadal structure in chicks indicated a high degree of sexual reversal in chicken treated with 3(NGSE3) and 4(NGSE4) mg of nanoparticles of grape seed extract and zinc. Conclusion is that the grape seed extract has the potential to act as an anti-aromatase compound to produce higher percentage of male broiler chicks.

This study was carried out to investigate the effects of savory essential oil on performance, some carcass traits, immunity and hematology of broiler chicks. To this aim, 400 Ross 308 male chicks were used in a completely randomized design with 5 treatments and 4 replicates and 20 broiler chicks per experimental unit. Experimental treatments consisted of negative control (without any additive in drinking water), positive control (drinking water containing Orego-Stim) and drinking water containing 100, 200 and 300 mg savory essential oil per liter. The results showed that the addition of all levels of savory essential oil to drinking water of broiler chicks in the first and second weeks of breeding resulted in a significant increase in feed intake. Moreover, at the first weeks use of 100 and 200 mg/lit of savory essential oil significantly improved weight gain and feed conversion ratio in all groups were less than negative control group (P<0.05). Relative weight of liver and abdominal fat was higher in chickens who received 100 mg/lit of savory essential oil in their drinking water than other groups (P<0.05). There was a significant difference among experimental treatments for some blood parameters such as blood lipids, MCH and AST liver enzyme content (P<0.05). The results indicated that the use of savory essential oil in drinking water has had a positive effect on growth performance and feed efficiency of broiler chicks, especially during the early period of rearing.

Methionine is the first limiting amino acid in poultry which has a primary role in stimulating protein synthesis and growth. This study was designed to investigate the effect of dietary intake of different levels of DL-methionine on hatchability, carcass characteristics, and blood parameters of day-old Ross 308 broiler chicks. For this purpose, 240 fertile broiler breeder eggs were used in a completely randomized design with eight treatments and 30 eggs per treatment. The experimental treatments included injection of different levels of DL-methionine (0.19, 0.38, 0.57, 0.76, 0.95, and 1.14 %) dissolved in 1 ml sterile distilled water, along with a sham-control group (sterile water injection) and a control group (non- injected). After hatching, the chickens were weighed and blood samples were taken and slaughtered to measure carcass characteristics. In ovo injection of different levels of DL-methionine caused a reduction in hatchability (P<0.01), especially by 1.14 % DL-methionine treatment. Based on the results, in ovo injection of DL-methionine increased carcass weight, carcass yield, thigh weight, relative thigh weight, proventriculus weight, liver weight, and relative liver weight (P<0.05). In ovo feeding of DL-methionine increased serum protein concentration (P<0.01), whilst decreased serum glucose and urea concentration (P<0.01). Hatchling weight, serum cholesterol and triglyceride oncentrations, and also immune system organs weight were not affected by treatments (P>0.05). The overall results of the present study indicated that regardless of low hatchability in methionine treatments, in ovo injection of 0.76% DL-methionine had the best growth response and then, is an advisable level of this experiment.

This study was conducted to evaluate the effect of different levels of herbal methionine in low protein diet on performance, carcass characteristics, immune response and some blood parameters in broiler chickens. In this experiment 240 day-old Ross 308 mixed broiler chicks were randomly divided into 6 groups with 4 replicates and 10 birds each in a completely randomized design. Treatments included: standard commercial diet with 100% synthetic methionine (DL-methionine) and low protein diet with different levels of herbal methionine (0, 15, 30, 45 and 60 percent) replaced with synthetic methionine respectively in grower (11 to 24 days of age) and finisher periods (25 to 41 days of age).Decreasing protein level significantly reduced feed intake in finisher and whole periods and reduced body weight gain in finisher period of the experiment (p<0.05). With increasing herbal methionine levels up to 60 % in low protein diet, feed conversion ratio significantly increased and body weight gain decreased in finisher and whole periods of the experiment (p<0.05). Decreasing dietary protein level, increased abdominal fat percentage and blood TG, cholesterol and VLDL concentrations at 41 days of age. Results of the present study indicated that herbal methionine could be replaced instead of synthetic methionine in low protein diet in grower and finisher diets of broiler chicks without any adverse effect on feed conversion ratio.

The use of medicinal plants in poultry nutrition has been considerably increased in the recent years due to their beneficial effects, environmental compatibility and lack of adverse side effects. On the other hand, the use of antibiotic growth promoters (AGPs) in poultry production has been banned because of their residues in poultry productions and development of antibiotic resistant bacteria. The plant yucca (Yucca schidigera) belongs to agavaceae family and is native of south-western of United States and Mexico. Yucca typically grows on rocky desert slopes and creosote desert flats between 300–1,200 meters altitude, rarely up to 2,500 meters. This plant thrives in full sun and in soil with excellent drainage. It also needs no summer water. The plant is known as one of the main sources of saponins. Steroidal saponins are accounted for approximately 10% of the dry weight of Yucca stem. Saponins, the main chemical component of YS extract, exist in steroidal form, whereas they are found in a triterpenoid form in other plants, such as Quillaja saponaria. Yucca saponins have antibacterial properties. The use of Yucca schidigera extract in poultry feed is a good alternative to improve feed efficiency and increased production. Yucca extract-supplemented diets have improved growth performance, relative weight of bursa of Fabricius and reduced mortality rate, breast muscle, caecal E. coli counts in broiler chickens. In the present study, the effects of different dietary levels of a commercial product containing Yucca schidigera powder on certain variables of broiler chicks were studied.
This experiment was conducted using 250 Ross 308 broiler chicks in a completely randomized design with 5 treatments and five replicates of 10 chicks each. Different dietary levels of the Yucca extract powder (0, 0.01, 0.015, 0.02, and 0.025 %) were tested in a three-stage feeding program including starter (0 to 10 days of age), grower (11 to 24 d) and finisher (25 to 42 d) phases. Blood samples were collected from one bird per replicate pen to determine the selected blood metabolites including cholesterol, triglycerides, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) at the end of the experiment (42 days of age). On day 42, one chick per replicate was slaughtered and carcass characteristics were assessed. The effect of dietary yucca powder levels on cellular immune response was determined by a cutaneous basophil hypersensitivity test using phytohemagglutinin-P (PHA-P). At d 42, one bird from each replicate was selected and thickness of the interdigital skin between the third and fourth digits of both feet was measured in millimeters with a Caliper (Measurement accuracy, 0.001). Immediately after the measurement, 100 µl of the PHA-P solution and phosphate buffer saline (PBS) were injected into the interdigital skin of the left and right feet by insulin syringes, respectively. Thicknesses of the skin were measured 12h and 24h post-injection. At day 28, five chicks per treatment (1 chick/replicate) were selected and 0.5 ml of 10 % sheep red blood cell (SRBC) solution was injected into their breast muscle and after seven days (day 35) blood samples were collected from brachial vein of the birds and then, an additional injection of SRBC was performed to induce the secondary anti-SRBC humoral response. At day 42, the second series of blood samples were collected. Sera separated from blood samples and were used to evaluate anti-SRBC total (Ig T), M (Ig M) and G (Ig G) immunoglobulins.
The effect of dietary Yucca powder on feed conversion ratio (FCR) was significant (P According to results of this experiment, supplementation of 0.02% Yucca extract powder, improved growth performance of the broiler chickens. However, 0.01% Yucca extracts powder improved humoral immunity and decreased blood serum LDL concentration of broiler chickens.