جستجوی مقالات مرتبط با کلیدواژه « microbial population » در نشریات گروه « علوم دام »

This research was conducted to compare the effect of different zinc sources on in vitro microbial populations, hydrolytic enzymes and ruminal fermentation products in sheep. Five diets without zinc supplement (control) or containing ZnSO4, ZnO, nano-ZnO and Zn-methionine were assessed. The 24 and 72-h gas tests were conducted in a completely randomized design where the microbial populations, hydrolytic enzymes, methane, antioxidant activity, organic matter digestibility (OMD), metabolizable energy (ME), truly degraded substrate (TDS), microbial biomass, partitioning factor (PF) and volatile fatty acids (VFA) were determined. Total proteolytic bacteria count and protease activity decreased due to the usage of organic, inorganic and nano-particle sources of zinc (P<0.05). The use of methionine, oxide and sulfate sources of zinc increased alpha-amylase activity (P<0.05). Total protozoa number in the 24-h incubation tended to decrease owing to dietary zinc supplements. Total cellulolytic bacteria, carboxymethyl-cellulase, microcrystalline-cellulase, filter paper-degrading activity, antioxidant capacity, microbial biomass and PF were the same among treatments. Zinc methionine, oxide and sulfate supplements increased OMD, ME, TDS and total VFA, whereas decreased ammonia and acetate:propionate ratio (P<0.05). Also, 24-h methane production decreased with the use of zinc supplements (P<0.05). Overall, the dietary addition of sulfate, oxide and methionine- sources of zinc is recommended with the aim of improving alpha-amylase activity and digestibility and reducing proteolytic activity, ammonia accumulation and methane, but feeding nano-ZnO is not recommended. More research is needed on the effect of zinc sources on rumen microorganisms and enzymes in different dietary conditions.

In order to investigate the effects of using live, autolyzed yeast and their combination on performance, and intestinal histology in Japanese quail, 360 of one-day-old chicks were used. Birds were randomly divided into 4 experimental groups in a completely randomized design with 6 replicates. The experimental groups included the control group: fed with basal diet without additives, the second group: fed with basal diet containing 0.4% live yeast, the third group: fed with basal diet containing 0.4% autolyzed yeast and the fourth group: fed with basal diet containing 0.2% live yeast and 0.2% autolyzed yeast. The results showed that the addition of autolyzed yeast caused the greatest increase in body weight gain compared to the control and their mixture in the whole period of experiment (P<0.05). The weight of thigh and pancreas as well as the length of duodenum increased significantly in birds fed with autolyzed yeast compared to live yeast and their mixture (P<0.05). The highest height of duodenal villi was observed in birds fed with autolyzed yeast and live yeast compared to the control treatment and their mixture. Birds fed with autolyzed yeast showed a significant decrease in E. coli bacteria and an increase in Lactobacillus bacteria (P<0.05). The results showed that the use of autolyzed yeast as well as live yeast can be useful in feeding Japanese quails due to improving performance, increasing the height of duodenal villi, reducing the microbial population of E. coli and increasing the cecal population of Lactobacillus.

[1]Selenium is an essential mineral for many metabolic functions of the body, including the activation of enzymes and the optimal biochemical and physiological function of birds (Antongiovanni et al., 2007). Selenium protects cell membranes from oxidative damage and can therefore improve nutrient efficiency (Arner et al., 2012). The small intestine is the most important part in the digestion and absorption of nutrients, while the large intestine and intestinal tract are very important areas for the accumulation of microbes (Chitra et al., 2013). Gastrointestinal health is one of the most important and effective factors in bird function. Gastrointestinal microbial population affects the nutrition and health of various animal species, including poultry. These microorganisms need trace elements such as selenium to perform their normal metabolic functions. Selenium may affect bacterial cells by disrupting the respiratory chain (Pappas et al., 2005). In addition to improving the quality and composition of intestinal microflora, selenium can have a positive effect on the morphology of the intestine as an antioxidant (Haghighi-khoshkhoo et al., 2010). Despite these benefits, the effect of selenium on intestinal microbial population is largely unknown, so the aim of this study was to investigate the effect of different levels of organic and inorganic selenium in the diet on microbial population, intestinal morphology and intestinal acidity in laying hens.

The experiment was conducted in a completely randomized design with 300 laying hens of high-line strains from 23 to 35 weeks of age with 5 treatments, 6 replications and 10 hens per replication. Experimental treatments include 1- Base diet (without selenium), 2- Base diet + 0.5 mg/kg sodium-selenite, 3- Base diet + mg/kg 1 selenite-sodium, 4- Base diet + mg/kg 0.5 selenium-methionine, 5-base diet + 1 mg/kg selenium-methionine. At the end of the experiment, two birds were randomly selected from each replicate; To evaluate the microbial population, a sample of the contents of the cecum on the culture medium was used (1). Tissue samples were prepared and then measured using a microscope, villi length, villi width, crypt depth, and number of goblet cells (9). To measure acidity, samples were taken from the contents of the cecum, and acidity was measured by a pH meter.

The results indicate that consuming 1 mg/kg of selenium-methionine increased the villi area compared to the control treatment. The experimental treatments did not affect villi length, villi width, crypt depth, number of goblet cells, and the ratio of villus length to crypt depth. The consumption of 1 mg/kg of selenium-methionine significantly decreased the population of Salmonella and increased the population of Lactobacillus in the cecal compared to other experimental treatments. The consumption of 0.5 and 1 mg/kg of selenium-methionine caused a significant decrease in the population of aerobic bacteria compared to the control treatment. The acidity of cecal contents in the treatment containing 1 mg/kg of selenium-methionine was significantly reduced compared to the control treatment. Several studies (Langhout et al., 1999, Lukaszewicz et al., 2011, Pappas et al., 2005) have reported that using organic sources of selenium reduces the coliform population. In mice, dogs, and laying hens, selenium intake has been shown to increase the number of Lactobacillus and decrease Escherichia coli and Staphylococcus aureus in the cecum (Langhout et al., 1999, Lukaszewicz et al., 2011, Pappas et al., 2005). Increasing the population of beneficial bacteria due to the provision of sufficient selenium for their synthesis is also an antioxidant property of selenium in preserving the life of these bacteria. It appears that beneficial bacteria, such as Lactobacillus, can competitively eliminate harmful bacteria such as Escherichia coli in the gut (Lukaszewicz et al., 2011). An increase in the number of pathogenic bacteria in the intestine causes the villi to shorten and the lining to shrink (Attia et al., 2010).Numerous studies demonstrate that the consumption of diets containing selenium compounds has destructive effects on harmful intestinal bacteria (Chantiratikul et al., 2008, Hashemi et al., 2012, Heindl et al., 2010, Horn et al., 2009, Langhout et al., 1999). Adding organic selenium to the diet of broilers increases the weight of the intestines due to the growth of villi and intestinal lamina propria (Haghighi-khoshkhoo et al., 2010, Heindl et al., 2010). The lack of selenium consumption on morphology can be attributed to the levels of selenium used, as well as the bird's lack of stress. Selenium can exert its effect more effectively under stress conditions. Most harmful bacteria grow in an environment with acidity close to 7 or slightly higher, while beneficial bacteria multiply in an acidic environment and compete with pathogenic bacteria (Cooke et al. 1973). An increase in acidity leads to a decrease in Escherichia coli and Salmonella in the gastrointestinal tract. Therefore, the consumption of organic sources of selenium reduces the population of pathogenic microorganisms (aerobic bacteria, Escherichia coli, and Salmonella) and increases the population of Lactobacillus competitively, followed by an increase in gastrointestinal acidity. This improvement may lead to an increase in digestion, absorption, and performance (Kasaikina et al., 2011).

 According to the results of this study, it can be said that consuming organic sources of selenium (levels of one and 0.5 mg of selenium-methionine per kg of feed) significantly reduces the population of harmful aerobic bacteria, bacteria. Salmonella and Escherichia coli and cause a competitive increase in the beneficial population of Lactobacillus; The consequence of this operation is to increase the acidity of the cecum and reduce the damage and microbial destruction to the intestinal tissue, and therefore with positive changes in the morphology of the small intestine will lead to improved bird function.

The use of antibiotics in poultry nutrition, in addition to their importance in preventing diseases, causes an increase in congenital anomalies, chronic diseases, increased microbial resistance and hundreds of other small and large complications, which is attributed to the current health problems of human society. The focus has always been on animal welfare, environmental care, limited use of medicines and the production of a healthy product without chemical residues that do not endanger human health. One of the suitable alternatives to antibiotics is bioactive peptides.

This experiment was used in a completely randomized design with 240 one-day old male commercial Ross 308 broilers in six treatments, five replications (eight chickens per replication). Experimental treatments include: basal diet, basal diet + 0.1% of vitamin E and 0.05% of maduramicin, basal diet + 0.05% of maduramicin, basal diet + 200 mg / kg superworm peptide, basal diet +400 mg / kg were superworm peptide and the basal diet was + 600 mg / kg superworm peptide. The effect of treatments on performance, microbial population, intestinal morphology and immune system response of broilers was investigated.

Addition of maduramicin (treatment 3) and superworm peptide at the levels of 200, 400 and 600 mg to the diet compared to the control group was able to reduce feed intake in the final period. On the other hand, treatments that used antibiotics, compared to treatment 5, which contained 400 mg of superworm peptide, were able to reduce the total bacterial population. Adding all levels of bioactive superworm peptide to the diet reduced the crypt diameter compared to the control group and also the diet containing 400 mg of the superworm peptide reduced the crypt depth compared to the control group. The results obtained in relation to immune factors can be stated that by adding antibiotics to the diet, it can increase immune factors such as immunoglobulin G at the age of 35 days compared to the control group, as well as the superworm peptide. At a concentration of 400 and 600 mg per diet, it was able to improve the total SRBC titer at 42 days of age compared to the control group.

The results of this experiment showed that the experimental treatments were able to improve the performance indices at the age of 11 to 42 days and some morphological features of the jejunum such as: crypt depth and diameter. Also, it can be said that the effect of experimental treatments on the total bacterial and lactobacilli population and the level of immunoglobulin G (day 35) and total SRBC titer (day 42) was significant.

Antibiotics have been routinely supplemented in diets of poultry to maintain their health, reduce stress, and enhance productivity. However, due to the development of resistance of bacteria to antibiotics and the possibility of these pathogens to be zoonotic, the use of various antibiotic products in livestock and poultry production is gradually being banned around the world. With the possibility of further ban in more regions of the world, research interest into alternatives to in-feed antibiotics has increased. One alternative to in-feed antibiotics that has gained research interest for use in poultry is yeast (Saccharomyces cerevisiae). Yeast in both probiotic (live) and prebiotic (dead) forms has been reported to provide several benefits to both healthy of animals, including poultry. The ability of yeast and its components to act as growth promoter could be associated with different mechanisms that it exhibits individually or synergistically. For instance, yeasts have been reported to favor the proliferation of beneficial microbes by serving as substrates for these microbes in the gut. These beneficial microbes, such as Lactobacillus, have been reported to improve gut health as well as exhibit growth-promoting effects in broiler chickens. Specifically, yeast cell wall that is extracted from whole yeast consists mainly of α-mannans and β-1–3-glucans, which are reported to prevent or eliminate bacterial infections. In order to study various levels of autolyzed yeast (Privita) on performance, quality characteristics of egg, cecal microbiology and intestinal histomorphology of laying hens (Hy-line W-36) (64 weeks), an experiment was done with 192 birds for 10 weeks. Treatments were various levels of autolyzed yeast (control, 250 ml/1000l, 500 ml/1000l, and 750 ml/1000l) that conducted in completely randomized design with 8 replications. Egg production (EP) and egg weight (EW) were recorded daily and feed intake (FI) and feed conversion ratio (FCR) were evaluated weekly. Quality characteristics of eggs were evaluated 2 times per period. Iintestinal histomorphology was determined at the end of experiment. At the end of the study, one birds per replicate were killed by cervical dislocation and blood was drawn from the jugular vein. Serum was separated after centrifugation at 4500 g and 4°C for 10 min, and frozen at −20°C until further analysis was conducted for blood biochemical parameters. Serum samples were analysed for concentrations of low-density lipoprotein (LDL), cholesterol, and triglycerides using standard kits (Zist Shimi, Tehran, Iran) with an autoanalyser (Autolab PM 4000; Medical System, Rome, Italy). Then, caecal digesta (1 g) from each bird were aseptically transferred into 9 ml of sterile saline solution and serially diluted. Lactobacilli, Coliforms, and E.Coli were grown on Rogosa–Sharpe agar, MacConkey Agar, and Eosin Methylene Blue Agar, respectively. Plates for Lactobacillus were incubated anaerobically for 48 h at 37 °C. Microbial populations for E. coli and Coliforms were counted after aerobic incubation at 37°C for 24 hours. All samples were plated in duplicate. This study results showed that addition of autolyzed yeast could not change performance parameters. Yolk color was highest at 250 ml/1000l which had a significant difference with 750 ml/1000l (P <0.05). Addition of autolyzes yeast at levels of 500 and 750 ml/1000l significantly increased cecal Lactobacillus and decreased Coliforms of cecum (P < 0.05). Addition of autolyzed yeast at level of 750 ml/1000l significantly decreased cecal Ecoli compared to the other treatments (P < 0.05). The possible reason for the observed response could be the ability of the yeast to maintenance of normal gut microflora as well as preventing the proliferation of pathogenic microbes. This action may partly contribute to increased nutrient digestibility, reduced competition for nutrients, increased nutrient utilization as well as absorption. Villus height of the e duodenum increased in layers fed on 750 ml/1000l compared to the birds fed 250 ml/1000l (P < 0.05). While crypt depth and villus height-to-crypt depth ratios of the duodenum in birds fed 750 ml/1000l compared to the birds 250 ml/1000l decreased and increased, respectively. Crypt depth of jejunum significantly decreased in birds fed highest level of autolyzed yeast compared to the other treatments. Results of this experiment showed that supplementation of autholyzed yeast could not significant change in qualitative and quantitative parameters. But, levels of 500 and 750 ml/1000l autholyzed yeast increased cecal microbial of Lactobacillus and decreased Coliform and the level of 750 ml/1000l decreased Ecoli of cecum and increased villus height and villus height-to-crypt depth ratios of the duodenum.

Today, livestock and poultry health in an advanced production system is a major challenge affecting human health and the global economy. Antibiotics have been used in poultry nutrition for many years. Chickens are raised with the assistance of the regular use of antibiotics, not only for the prevention and treatment of diseases but, also, for body growth. Overuse and misuse of antibiotics in animals are contributing to the rising threat of antibiotic resistance. In recent years, as a result of increasing concerns about the possibility of developing antibiotic-resistant strains, as well as the fact that they remain in animal tissues and eventually ban their use, the use of compounds such as organic acids, probiotics, prebiotics, enzymes, etc. as safe alternatives have been widely considered in poultry nutrition. Organic acids are a good alternative to antibiotics in poultry diets. These are improving the immune system of broilers by acidifying the gastrointestinal tract and improving the intestinal microflora. Organic acids cross the bacterial membrane; inside the bacterial cell, it produces hydrogen ions and bicarbonate, which eventually increases the acidity. Therefore, they force the bacteria to consume energy in order to keep the acidity constant, which leads to their death. Coating of organic acids prevents its dissociation and digestion in the stomach so that the biological effect of organic acids reaches the distal parts of the gastrointestinal tract and is effective in intestinal microflora and mucosal morphology. This study was performed to investigate the effect of encapsulated organic acids on microbial population, intestinal acidity, blood indices, nutrient digestibility, and viscosity of digestive contents, carcass characteristics and performance of broilers. 150 male broiler chickens of Ross 308 commercial strain as one-day-old were allocated in a completely randomized design with 5 treatments, 3 replications and 10 chickens per replicate. Experimental treatments included: 1. Basal diet 2. Basal diet + commercial Organic acid 3. Basal diet + Non-encapsulated organic acid 4. Basal diet + Encapsulated organic acid 5. Basal diet + encapsulated organic acid + Non-encapsulated organic acid. On day 42 of the experiment, one chickens from each experimental unit, which were close to the weight average of that unit, were selected and blood samples were taken from their wing veins. AT 42d, from each replication, a chick with the same weight as the average weight of the experimental unit was taken and their live weight was recorded and slaughtered. Also, from each replication, a chick with a weight similar to the average weight of the experimental unit was selected and their live weight was recorded and slaughtered. Then, different parts of the carcass were weighed by peeling and emptying the viscera. In order to evaluate the microbial population of the intestines of the tested broilers, at the age of 42 days, one chick from each experimental unit was selected with conditions close to the weight average of the relevant unit and after weighing, it was slaughtered. The microbial population of Lactobacillus and gram-positive and gram-negative bacteria were studied.The data were statistically analyzed by statistical software using GLM procedure. The means were compared by Duncan method at the significance level of 0.05%. The result showed that in growth cycle, weight gain during the growth period and the whole period in the treatments containing encapsulated organic acid showed improvement and a significant difference with the control treatment. The addition of organic acids to the diet during the growth period reduced the conversion coefficient compared to the control group. Feed intake in the treatments containing capsular organic acid showed a significant decrease compare to the control group. The acidity of the duodenum and jejunum showed a significant decrease compared to the control group. The addition of encapsulated organic acids significantly reduced the total number of coliforms in the ileum and duodenum and increased the number of lactobacilli in the ileum. Also, experimental treatments increased the apparent digestibility of crude fat compared to the control group. The weight of the lymph nodes (bursa and spleen) also showed a significant increase under the influence of organic acids. The results of current experimental study showed that the usage of encapsulated organic acids in broiler chicken diets, reduces the acidity of the digestive tract, reduces the intestinal microbial contamination, creates favorable conditions in the digestive system, improves digestibility of the nutrients, and performance of the bird's growing birds.

By increasing the poultry and broiler production industry, concerns for  having a food free of pathogens, and as a result, producing a quality and healthy product are increasing. Therefore, correct and efficient disinfection of poultry diets with maintaining the quality of them is very important. The aim of this study was to investigate the effect of gasification of complete poultry feed by ozone on microbial papulation and the quality of broilers diets.

From 432 commercial male Ross strains in a 2 × 2 factorial experiment with three levels of ozone gas (zero, 20 and 30 ppm) and two levels of low fat (1.5 and 2% vegetable oil for growth and finishing periods respectively) and high fat (3 and 4% of vegetable oil for growth and finishing periods, respectively) were used in a completely randomized design with 6 treatments and 4 replications. Diets were ozonated for 120 minutes at concentrations of 20 and 30 ppm. Aflatoxin B1 levels, microbial papulation and the presence of fungi in the feed as well as oxidation of feed lipids in broiler chickens were assayed  after ozonation.

Aflatoxin B1 was not found in grower and finishe diets. The lipid oxidation in ozonated diets with 30 ppm was significantly higher than non-ozonated diets (P<0.05).

According to the results of this experiment, the use of ozone gas to disinfect the broiler chickens diets, despite the destruction and inactivation of microbes and fungi, increases the oxidation of dietary fats.

Due to population growth and increasing demand for protein sources, poultry farming became industrialized. This has increased the density of breeding per unit area and also increased the likelihood of disease in them. However, the spread of diseases has led to a greater tendency to use antibiotics. Therefore, one of the ways to reduce the use of antibiotics is to use medicinal plants, such as mint. Therefore, an experiment was performed to investigate the effects of reducing dietary protein levels and adding peppermint extract on the performance of male Ross 308 broilers.

An experiment was conducted in a completely unbalanced random design with 2×2 factorial methods with four treatments, four replications and 10 chickens per replication. Experimental diets include: a) control diet with standard protein and without peppermint extract, two) control diet with three tenths percent of peppermint extract diet, three) low protein diet without peppermint extract, four) low protein diet with the addition of three tenth percent of the ration was peppermint extract. During the experiment, the birds' performance was evaluated periodically, blood parameters, immune response, meat quality, microbial population and carcass characteristics.

During the growing period and the whole breeding period, feed consumption and weight gain in the treatment containing low protein diet with peppermint extract increased significantly compared to the treatment with low protein diet without peppermint extract. The lowest feed conversion ratio was observed in the growing, final and whole growing years in the control treatment containing peppermint extract. Also the lowest percentage of Abdominal fat belonged to the control treatment containing peppermint extract (p<0.05). At 21 and 42 days of age, the lowest level of triglyceride was observed in the control treatment with 0.3% peppermint extract (p<0.05). In this experiment, meat malondialdehyde concentration and microbial population were not affected by experimental treatments.

The results of this experiment showed that adding peppermint extract to the diet from the growing period can improve yield.

Low feed efficiency is one of the problems in the rumen of ruminants, which results in reduced growth and production of livestock and, most importantly, environmental pollution due to the release of methane and nitrogenous compounds . Changes in ruminal fermentation can be made to improve fermentation efficiency and substrate utilization and optimize feed nutritional value . Antibiotics have been successful in reducing energy loss (from methane) and protein (from ammonia nitrogen) in the rumen . However, today, due to general concerns about the remains of these compounds in milk and meat and thus increasing the bacterial resistance to them has caused the use of materials in feed as additive in some countries . Therefore, the tendency to find alternatives with natural origin for antibiotics has increased over recent years .Plant secondary metabolites are among the natural alternatives that have been studied in recent years that have antimicrobial properties.Essential oils, also known as volatile or ethereal oils, occur in edible, medicinal, andherbal plants. As these aromatic compounds are largely volatile, they are commonly extracted by steam distillation or solvent extraction . Essential oils can be extracted from many parts of a plant, including the leaves, flowers, stem, seeds, roots and bark. However, the composition of the EO can vary among different parts of the same plant . For instance, EO obtained from the seeds of coriander (Coriandrum sativum L.) have a different composition from the EO of cilantro, which is obtained from the immature leaves of the same plant . Chemical differences among EO extracted from individual plants, or different varieties of plants, also exist and are attributed to genetically determined properties, age of the plant, and the environment in which the plant grows . One of the plant essential oils that has a great potential for use in ruminant diets is the essential oil of thyme (Thymus Vulgaris). Thyme extract contains 0.6-8.8% (usually 1%) of essential oil, most of which are phenols (20-20%) and monoterpene hydrocarbons (such as P cymen and γ terpinen) and alcohols (such as Linalool and terpinen α). They show that sometimes these compounds make up 80% of the extract compounds. Naturally, thymol is also a major phenolic component in thyme and carvacrol is a sub – element (Leung and Foster., 1996). Although goats and sheep have often been fed and managed in a similar manner (goats being browsers and sheep being grazers), they are different, especially in their digestive capability, because of differences in the morphology of digestive system, including the mouth structure and gut, which may influence their ability to ingest and digest feed materials . Available information on efficiency of feed utilization between goat and sheep has been inconsistent with several studies reported sheep had higher growth performance than goats . In a recent in vitro study, Candyrine et al (2016) reported that goats had better rumen fermentation characteristics, including higher volatile fatty acids (VFAs) production and higher population of cellulolytic bacteria compared to sheep, suggesting that goats could be more superior in digesting feed materials.The results of studies performed on lambs and goats ) that have examined the effects of thyme extract or its major compounds (thymol and carvacrol) are very contradictory. And more research is needed to determine their effects on rumen fermentation and metabolism in lambs and goats. There is also little research on direct comparisons of the use of plant extracts in vivo between lambs and goats. Therefore, the aim of the present study was to compare these two species and the effects of thyme extract on performance and some ruminal parameters in fattening lambs and goat kids.The aim of this study was to investigate the effect of different levels of thyme (Thymus vulgaris) extract on growth performance, feed intake, daily weight gain and digestibility of nutrients in fattening lambs and kids. For this purpose, 15 goat kids (average initial BW of 17.3 ± 1.2 Kg, 3 month- old) and 15 Dalagh lambs (average initial BW of 21.4 ± 1.5 Kg, 3 month- old) were randomly assigned to 3 dietary treatments: 1) control (without thyme extract), 2) supplemented with 250 ml thyme extract and 3) supplemented with 500 ml thyme extract. Animals were kept in individual pens with self-mangers for 84 days. The results showed that there was no significant difference in nitrogen consumption through the use of extracts between different treatments. However, fecal and urinary excretion nitrogen was lower in treatments receiving 250 ml of thyme extract and retained and digested nitrogen was more than other treatments (P <0.01). Examination of interactions and species effects showed that the effect of thyme extract on excreted nitrogen and nitrogen retention in lambs was different from that of goat kids, so that excreted nitrogen was higher in goats and nitrogen retention was lower. With increasing levels of thyme extract, a significant decrease in gas and methane production was observed in both species (P <0.01). Rumen microbial population (total bacteria, coliforms and lactic acid bacteria) decreased due to the addition of thyme extract in both species, but this decrease was not significant. Also, in lambs and goats receiving thyme extract, with increasing the levels of the extract in the diet, the number of protozoa decreased significantly (P <0.01), so that the group receiving 500 ml of extract had the lowest number of protozoa. Concentrations of triglycerides, cholesterol, low-density lipoprotein and high-density lipoprotein were not affected by the use of the extract. However, blood glucose concentration increased significantly with increasing the extract in the diet and blood urea nitrogen concentration decreased (P <0.01). In general, the results of this study showed that the use of thyme extract in the diets of lambs and goats can significantly reduce gas production, especially methane gas and excretion of nitrogen through urine and feces, and thus increase nitrogen retention and digestion.

This experiment was conducted in order to investigate the effect of dietary enzyme supplementation (DES) and wheat particle size (WPZ) on growth, microbial population and intestinal acidity and litter characteristics of Japanese quails using a 3×3 factorial arrangement in a completely randomized design with nine treatments each replicated 4 times with 20 quails per replicate. The experimental factors included three WPZ [2, 3 and 3/5 mm] and three levels of DES [Rovabio enzyme at 0, 200 and 400 ppm]. Through the whole experimental period, groups of birds received diets with 2 and 3 mm WPZ+400 ppm of DES showed significantly reduced feed intake compared to the groups with 3.5 mm WPZ without and with 200 ppm DES (p<0.01). Birds received diets with 2 and 3 mm WPZ+400 ppm of DES also showed better feed conversion ratio than those fed with 3.5 mm WPZ without enzyme supplementation (p<0.01). Lactobacillus counts increased significantly in quails fed diets with 2 mm WPZ and 400 ppm of DES in comparison to 3.5 WPZ without enzyme supplementation group (p<0.01). Birds fed diets with 2, 3 and 3.5 mm WPZ+400 ppm of DES had lower litter pH than those fed wheat-based diets without enzyme supplementation (p<0.01). Treatment of 2 mm WPZ+400 ppm of DES showed less litter moisture than those with 3 and 3.5 mm WPZ without enzyme supplementation (p<0.01). In conclusion, dietary inclusion of wheat grain at 2 mm diameter particle size supplemented by 400 ppm enzyme is recommended.

The effects of different sources of copper supplementation on growth performance, some blood biochemical and immune parameters,microbial population of small intestine and meat quality were investigated with using of 240 male broiler chicks in a completely randomizeddesign with 5 treatments and 4 replicates from 1 to 42 days. Treatments consisted of control treatment (basal diet without copper supplement)and four diets containing 16 mg/kg of copper-glycine, copper-sulfate, copper-nanochelate and copper nano-glycinec. The results showed thatthe use of different sources of copper had no effect on growth performance, some blood biochemical parameters and percentage ofheterophil, lymphocyte, white blood cell, antibody titer against Newcastle disease, cholesterol, triglycerides and water holding capacity andpH of meat of broilers. Gastrointestinal relative weight in birds fed with diet containing copper-glycine was lower than the birds receivingcopper-nanochelate (P<0.05). The total microbial population of ileum in birds fed diets without copper and copper-sulfate was higher thanbirds receiving diet containing copper-glycine (P<0.01). Meat malondialdehyde concentration of birds fed with diets containing copperglycineand copper nano-glycine after 6 day of storage at refrigerator was lower than other birds (P<0.01). According to the results, the useof 16 mg/kg of copper from organic, mineral and nano sources in the diet has no effect on growth performance, immune system and ilealmicrobiota in broilers, but the use of copper-glycine and copper nano-glycine supplements in the diet reduces the oxidation of meat.

The aim of this study was to investigate the effect of Lactobacillus fermentum 92069 (LF) isolated from yogurt on chemical and microbialfermentation and aerobic stability of high moisture corn silage. After propagation and concentration determination LF was used to prepareexperimental treatments with concentrations of zero (control, LF0), 1×106 cfu/g fresh forage (LF1) and 2×106 cfu/g fresh forage (LF2). Three replicatesof each treatment were stored in laboratory silos for 90 days. The results showed that the chemical composition of silages (DM, NDF, ADF, CP,WSC) was not affected by addition of LF. LF2 had a significant lower pH compared to the control (P<0.05). LF1 and LF2 silages showed a higherconcentration of lactic acid (P<0.05). Concentration of acetic acid increased and mold population decreased in LF2 compared to the other silages(P<0.05). There was no significant difference between population of lactic acid bacteria and yeast in silages. The aerobic stability of LF0 and LF1silages decreased significantly compared to LF2 (P<0.05). During the aerobic stage after opening the silos, LF2 silage had the lowest pH (P<0.05).However, yeast population of silages during the aerobic stage was not affected by treatment. The results of this study showed that Lactobacillusfermentum 92069 has the potential to be used as a silage inoculant.

This study was carried out to evaluate the effect of lecithin emulsifier to diet containing different levels of energy on performance, carcass characteristics, intestinal microflora and nutrient digestibility of broiler chicken. A total of 200 day old broiler chicks (male sex) Ross 308 strain was divided in 4 treatments, 5 replicates and 10 chicks in each replicate in a completely randomized design. Experimental treatments include: diet containing soybean oil with standard energy, diet containing soybean oil with low energy, diet containing soybean oil with standard energy + emulsifier, diet containing soybean oil with low energy + emulsifier. The Results showed that in the case of weight gain throughout the period, the body weight of chickens increased with decreasing energy levels. Also in the case of weight gain in the final period and the whole period, with increasing the level of emulsifier, body weight decreased. Regarding the FCR, in the initial, and whole growth periods, increasing the emulsifier level increased the feed conversion ratio. No statistically significant effects were observed in other experimental traits and different breeding periods by changing the energy level and adding emulsifier (P>0.05). The percentage of thighs in diets with high energy level was higher than other treatments. But other carcass traits did not show any significant effect (P>0.05). No effect of treatments was observed on intestinal microbial population. The results related to digestibility showed that in the case of dry matter, organic matter and fat traits, digestion was reduced in standard diets containing emulsifier and no significant effects were observed in other traits (P>0.05). In general, it can be said that increasing energy levels caused weight loss and reduced nutrient digestion, and adding emulsifier caused weight loss, increased conversion ratio and reduced nutrient digestion.

The aim of this study was to invastigate the effect of organic acids and silver nanoparticles coated on zeolite on performance, intestinal morphology and gastrointestinal microbial population in broiler chickens. A total of 375 one-day old broiler chickens were randomly assigned to 5 diets including: (1) a basal diet (control), (2) the basal diet containing 1% zeolite, (3) the basal diet containing 1% of zeolite-coated with 0.5% silver nanoparticles, (4) the basal diet containing 1/5 g/kg Organic acids and (5) the basal diet containing 1% of zeolite-coated with 0.5% of silver nanoparticles and 1/5g/kg organic acids. The experimental treatments had no significant effect on performance characterization of birds (P>0.05). Total count of anaerobic bacteria in ceca was decreased on silver nanoparticles coated on zeolite treatment on 21 d of experiment (p < 0.05). The number of lactobacillus bacteria in ileum was increased in all of treatments compared to the control group on 42 d of experiment (p < 0.05) and both tretments contain with organic acid were the most number of lactobacillus bacteria in ceca (p < 0.05). The use of silver nanoparticles coated on zeolite in chickens significantly increased villi length, villi/crypt depth, villus surface area, muscular layer thickness and decreased crypt depth and villus width compared to control treatment (p < 0.05). In conclusion silver nanoparticles coated on zeolite in broilers diet can increase intestinal lactobacillus and could be used as growth and health promoter supplements in broiler chickens feed.

This research was conducted to compare the immune system status, microbial population, blood parameters and performance traits of five common broiler strains in Iran. For this purpose, fertile eggs were prepared from broiler breeder flocks with 31 to 33 weeks of age including Arbor Acres, Arian, Ross 308, Cobb and Hubbard and a total of 260 one-day old broiler chick were raised in the same production condition for 49 days in a completely randomized design with 5 treatments(strains),4 replicates and 13 birds in each replication. The mean of live body weight, feed conversion ratio and production index were not significant among treatments. The highest and lowest feed intake were related to Ross 308 and Arian, respectively(p < 0.05). The difference was not significant in total white blood cells, lymphocyte, heterophile, eosinophil, monocyte and heterophile/lymphocyte ratio among treatments at 21 and 42 d.The effect of strain was not significant on relative weights of immune system organs including spleen and bursa of Fabricius at 21 and 42 d.The activity of aspartate aminotransferase enzyme did not show any significant difference among different experimental strains. The different experimental treatments had no significant effect on lactobacillus and Escerichia coli population and blood triglyceride, HDL and LDL concentrations at the end of experimental period.In general,the results of this examination showed that production index,immune system and microbial population of these strains were almost the same in identical production conditions so that broiler producers can raise each of these strains according to the quality of their one- day old chicks

Nowadays silver nanoparticles are being considered as an alternative to antibiotics. Silver is one of the most important elements in nanotechnology due to extensive antibacterial activity. The aim of present experiment was to evaluate the effect of silver nanoparticles coated on zeolite and organic acids on performance, intestinal morphology, gastrointestinal microbial population and carcass characteristics in broiler chickens under heat stress conditions. A total of 375 day-old (Cobb 500) broiler chickens were randomly assigned to 5 treatment groups consisting of 5 replicates of 15 birds in each. Treatments included: (1) basal diet, (2) basal diet containing 1% zeolite, (3) basal diet containing 1% of zeolite-coated with 0.5% silver nanoparticles, (4) Basal diet containing 1 g/kg a mixture of organic acids and (5) Basal diet containing 1% of zeolite-coated with 0.5% of silver nanoparticles and 1g/kg a mixture of organic acids. Two chickens per each replicate were slaughtered on days 21 and 42 for measuring of the internal organs weight and microbial population enumerating, and on days 35 and 42 for morphology of the intestine. The experimental results showed that silver nanoparticles had higher feed conversion rate compared with other treatments. Also, villi length was significantly different between treatments and control group on d 35 of experiment (P<0.05). The silver nanoparticles treatment and the silver nanoparticles with organic acids treatment had the highest villi length on 42 d of experiment (P<0.05). The effect of experimental treatments had no significant effect on gastrointestinal microbial population on d 21 and 42 of experiment (P>0.05). In conclusion, the results of present study showed that silver nanoparticles coated on zeolite with organic acid could be used as a feed additive with no adverse effect under heat stress condition in broilers chicken treatments.

The aim of current research was to investigate the efficiency of dietary addition of ASRI1® and ASRI2® toxin binders and probiotic on performance, Aflatoxin concentrations of liver and muscle and intestinal microbial population of broiler chicks fed Aflatoxin-contaminated diets. A total of 420 one-day old Ross 308 broiler chicks were assigned in a completely randomized design to 7 treatments with 5 replications of 12 birds in each. The experimental treatments 1) non Aflatoxin contaminated diets or negative control (NC), 2) Aflatoxin-contaminated diets or positive control (PC), 3) PC diets containing ASRI1® toxin binder, 4) PC diet containing ASRI2® toxin binder, 5) PC diet containing probiotic, 6) PC diet containing probiotic+ ASRI1® toxin binder and 7) PC diet containing probiotic+ ASRI2® toxin binder. Performance was evaluated in periodical, Aflatoxin concentrations of liver and muscle at 28 and 42 days of age and intestinal microbial population at 42 days. The results showed body weight was significantly lower (p < 0.05) and feed conversion ratio was significantly higher (p < 0.05) in NC group when compared with PC group in grower and finisher periods. The harmful microbial population and Aflatoxin concentrations of liver and muscle were significantly higher (p < 0.01) in PC group in comparison to NC group. However, the dietary addition of commercial toxin binders and probiotic especially their combination, significantly alleviated (p < 0.05) Aflatoxin effects on performance, Aflatoxin concentrations of liver and muscle and intestinal microbial population.

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.

In recent years, the advances made in the field of genetics, food, breeding, and marketing in the poultry industry have led to the use of modern methods and devices to achieve the highest production with the lowest cost in the industry. So today, food additives are used in the poultry industry to achieve high production with the lowest cost. Medicinal plants contain substances called active ingredient or active ingredients are made and stored and have physiological effects are on the body of a living creature leave. Medicinal plants due to certain compounds can affect the production and improving digestive and finally affect the bird feed digestibility. This plant contains active ingredients: Capsaicin and is capsanthin. Some antimicrobial compounds extracted from plants including: Terpiner, Betapinen, alfapinen, Linaleolandterpineol.

n this study 160 day-old male (Ross 308) broiler chicks in a completely randomized design with 4 treatments and 4 replicates per treatment, were used from age 1 to 42 days. In each
experimental unit 10 chicks were reared in the same environmental conditions. Experimental diets (treatments) were as consisted of 1) basal diet without additives (control), 2) control diet containing 0.04 percent Flavophospholipol, 3) control diet containing 0.1% of red pepper powder, 4) control diet containing 0.3% of red pepper powder, diets were fed in two periods. Body weight and feed intake were measured weekly and daily mortality was recorded and then these data were used to calculate the performance parameters of body weight gain, feed intake, feed conversion ratio. To study the structure of the ileum villus tissue sample of the target tissue as much as 4 cm from the beginning of the ileum supply and after unloading
the contents and washing was kept in 10% formalin paraffin wax technique for producing histological slides were thin.

The results showed that weight gain, feed intake and feed conversion were not affected by treatments. The addition of red pepper powder did not have a significant effect on the body
weight of broiler chicks, consuming more than one percent of the red pepper extract had no effect on weight gain, possibly due to an increase in the intake of red pepper fruit in broiler chickens. Capsaicin stimulates fat metabolism from stored tissue and also activates both liver enzymes G6PD and lipoprotein lipase and thus does not affect weight gain. Adding capsaicin 0.2% does not affect feed intake. It has also been reported that no difference was found in the consumption of broiler chickens fed with Pune, Cinnamon and Pepper extract with five grams of Lamiaceae plants. Medicinal plants, as part of active substances, are very mischievous or may have a nasty taste, and in the diet may cause the animal to refuse eating and reduce feed intake. Adding
capsaicin 0.2% does not affect feed intake (13). It has also been reported that no difference was found in the consumption of broiler chickens fed with Pune, Cinnamon and Pepper extract with five grams of Lamiaceae plants. Based on these results, feeding with 0.1% red pepper powder increased the lactobacillus population as compared to the control and antibiotic group (P <0.05). Also, the total amount of the formulas in the treatment fed with 0.1% red pepper and antibiotic was decreased in comparison with the control (P <0.05). Red pepper powder, due to capsaicin, reduces the pH of the diet and thus increases the bacteria producing lactic acid and reduces the total bacterial form. A mixture of capsaicin, cinnamaldehyde and caracole
reduced the number of pericardial cholera and pericardial cholestridium in the intestinal tract. Vegetative herbicides reduced the number of asherikhakli e coli and Clostridium perfringens in the intestines of broiler chicks. Also, a mixture of herbal essential oils can reduce colonies of clostridium performs in the intestine and feces of broiler chicks. Lactobacilli is produced by the production of lactic acid as an antimicrobial that eliminates the external membrane of gram-negative bacteria, and, by decreasing the intestinal pH, inhibits the growth of pathogenic bacteria. Antibacterial activity of medicinal plants is directly related to the concentration and composition of the active ingredients. These compounds reduce the thickness of the intestinal epithelium, modify the microbial population and reduce the pathogenic microorganisms of the poultry function Improve The results of this study showed that feeding with red pepper powder increased the length of upper ileum compared to the control group (P <0.05). Upper ileum increased in chicken fed 0.1% red pepper in comparison with the control and antibiotic groups (P <0.05). Crypt depth was not affected by experimental treatments. In the case of herbs, there are various reports of increasing, no change, as well as a decrease in the length and depth of the intestines of broilers during the use of medicinal plants.

In the present study, the use of red pepper powder increased the useful bacteria (lactobacilli) and reduced the harmful ones (total polymorphisms). It also increased the length and width of the intestines of broiler chickens, although it did not have a significant effect on yield. Therefore, red pepper can be thought of as a suitable alternative to flavophospholipol antibiotics by reducing the overall bacterial form and increasing the intestinal parenchyma