Enzymes and probiotics are often used in feeding of poultry in intensive rearing systems. Beneficial effects of probiotics were observed in toxin neutralization, prevention of development and multiplication of specific bacteria, change in microbial metabolism and immunity stimulation. Administration of useful microorganisms as probiotic into diet usually cause enhancement of organic acids production such as lactic acid that in turn can reduce gastrointestinal pH and subsequent prevention of pathogen microorganisms such as salmonella to colonize the alimentary tract(Fuller, 1992). Exogenous enzymes have been shown to alleviate the adverse effects of high viscosity of digesta in the small intestine and to improve digestion (Petersen et al. 1999). Pervious studies demonstrate that simultaneously using probiotics and enzymes in broiler diets, improve their growth performance (Midili, and Tuncer, 2001). The objective of the present study was to examine the influence of probiotic (protexin) and enzyme (Natozyme) supplementation on the performance of broilers fed diets containing wheat.

Lysine is the reference amino acid (AA) in the ideal AA ratios for chickens. Feed formulation based on digestible AA has been shown to increase weight gain and feed intake and improve body composition in broilers. Amino acid (AA) in most feed ingredients will not be totally digested, and knowledge of such efficiency is important in formulating diets and will be used to eliminate differences in absorption efficiencies due to feedstuff sources. This study was conducted to evaluate the growth performance and blood parameters of broilers fed various levels of DL (Digestible Lysine) supplemented in diets from day 1 to day 18.

lysine is an essential amino acid that promotes normal growth by helping to maintain the proper protein balance in the body. Most vegetable protein sources used in poultry diet formulations are moderate to low in lysine contents; hence supplementation with lysine is inevitable in growing broilers to ensure rapid growth and optimum efficiency of feed utilization. Adequate supply of nutrients during the starter improves gut development and could result in long term improvements in feed utilization. In order to evaluate the effect of different digestible lysine dietary levels on growth and immune response in starter, this experiment was done.

In view of the severe restriction or total ban on the use of antibiotics as growth promoters and therapeutic agents in poultry industry, probiotics and prebiotics have been suggested as alternatives to antibiotics (piray et al, 2007). Prebiotic are known as “a nondigestible feed ingredient” that beneficially affects the host by selectively stimulating the growth or activity of a limited number of bacteria in the colon (Gibson and Roberfroid, 1995). Prebiotics has a significant effect on body weight gain and feed to gain ratio (piray et al, 2007). The objective of this research was to study the effectiveness of adding prebiotic on broiler growth performance in low protein diets.

Research on poultry genetics, feeding and management for BWG and FCR resulted in fast growth but decreased the quality of poultry products as modern fast growing broilers have been found to contain higher amount of abdominal fat (Chambers et al, 1981). Most recently considerable attention has been paid to test the potency of growth promo ants on altering lipid metabolism, because, Word Health Organization suggest that excess fat deposition is undesirable in human body. Recent report suggested that feeding of chicory beta fructans; a prebiotic reduced the serum cholesterol and abdominal fat of broiler chicken. The present study was undertaken to study the effect of Aspergillus meal prebiotic (Fermacto) on abdominal fat, serum total cholesterol, HDL and triglyceride levels in low protein diets.

Enhanced nutrient digestion and absorption in enzyme supplemented broiler diets could be either through reduced digesta viscosity or weakening of the cage effect elicited by soluble or insoluble Non – Starch – Polysaccharides (NSP) on nutrient digestion and absorption. Inhibitory effect of insoluble NSP on endogenous protease reduces efficient digestion of nutrients embedded in cell wall matrix of grains. Increased amount of undigested and unabsorbed protein reaching the caecum implies available nutrient for fermentation and increased coliform forming units of such bacteria as clostridium that ferment proteins, peptides and amino acids. The study aimed to assess the effect of partial replacement of maize with Rice Husk (RH) supplemented with Roxazyme G2 G enzyme on ileal crude protein digestibility, caecal crude protein retention and digesta viscosity in broilers.

Although antibiotics treatment has been used as an efficient technique to control infectious diseases in poultry industry, there are intensive studies to decrease the use of antibiotics because of the increase in microbial resistance. Therefore, enhancing protective immunity with immunostimulators by magnifying the capacity of immune response seems to be the most promising and practical approach. Alliums have been reported to possess therapeutic properties often attributed to sulphur-containing compounds (Bonaccorsi et al., 2005). In addition to these compounds, Allium cepa is among the richest dietary flavonoids sources; those flavonoids have shown in mammals in vitro antimicrobial and anticarcinogenic activities (Block et al., 1992). However, very few studies aimed at examining their effects in poultry have been performed. The objective of this study is to examine if the addition of supplementary Allium cepa to a balanced ration enhances the immune response of chickens after immunization.

Recently, production of poultry by – product meal (PBPM) has been increased in the northwest of Iran, East Azarbijan. PBPM has a profile of available essential amino acids and is rich in calcium, phosphorus and vitamin B12 (NRC 1994). The chemical composition and mineral content can vary greatly depending on raw material and processing conditions. In our country, fish meal is a common ingredient as animal protein in poultry diets. However, fish meal is imported at high cost. In recent years, there have been attention paid to PBPM supplementation in diets by East Azarbijan poultry feed industry. Therefore, the present study was conducted to determine the chemical composition, mineral content and to study the effects of different dietary concentration (3, 6 and 9%) of PBPM on broiler performance.

Canola meal (CM) is a suitable protein source in poultry diets, although it contains a number of antinutritive factors including non-starch polysaccharides and phytic acid. These factors can limit inclusion rate of canola meal in poultry diets (Kocher et al., 2000). The negative correlation between NSP levels and nutritive value of the diet has been demonstrated in poultry (Choct and Annison, 1990). In addition to reducing the availability of phosphorus to birds, phytates are also associated with a number of antinutritional effects, largely because they can chelate divalent cations and reduce protein availability (Ravindran et al., 1995). Successful use of enzymes in cereal-based diets has stimulated interest in the application of enzymes to target the vegetable protein components of poultry diets as well. The current study was, therefore, conducted to investigate the effects of a multi-enzyme on performance and serum thyroid hormone concentrations of broilers fed rations in which soybean meal was replaced by CM.

Today the use of enzymes is common in practical poultry nutrition. Enzyme supplementation usually result in numerous beneficial effects, such as increased utilization of nutrients (e.g. fat & protein), improved AME values, increased growth rate, improved feed conversion ratio, decreased viscosity of intestinal digesta, reduced incidence of sticky excreta and improved litter conditions (Broz and Ward., 2007). The use of multi enzymes to improve the digestibility of corn-soybean meal-wheat diets for broilers is less well documented than wheat and barely diets. Therefore, the aim of the present study was to examine the effects of a multi-enzyme supplementation on the performance of broiler chicks fed on corn-soybean meal-wheat diets.

N-3 fatty acids are essential for normal growth and development, and may play an important role in prevention of coronary artery disease, hypertension, diabetes, arthritis, other inflammatory and autoimmune disorders and cancer in humans (Simopoulos, 1999). Fatty acid profiles of broiler meat may be modified by adding fish oils to the diet (Lopez-Ferrer et al., 2001). When meat is enriched with PUFA, particularly n-3 long-chain fatty acids (C≥20), all sources of added vegetable oils seem to be less effective than marine oils (Bou. R et al., 2004). The purpose of this experiment was to study the effect of dietary fish oil on fatty acid composition of thigh and breast meat in broiler chickens.

Based on the official statistics of industries and mines organization about 1000 ton wastes of spaghetti, pasta, biscuit, crisp, and about 7500 ton waste of chick pea pre-cleaning plants are produced annually in East Azerbaijan province of Iran. In our country there is little researches on wastes. In one study, ileal amino-acid digestibility of wheat, autoclaved wheat and spaghetti by-products for broiler chicks was determined (Zaghari 2006). The aim of the present study was to determine metabolizable energy and chemical composition of wastes of spaghetti, pasta, biscuit, crisp, chickpea pre-cleaning and chickpea screening plants.

Lighting is very important for turkey production, because their life period is longer than poultry (Nixey 1994). One of the important effects of lighting is to change the time of sexual maturity in pullets. Classen et al. (1994) concluded that constant light causes an increase incidence of leg problem and metabolic disorders. With lighting programs and lighting intensity, time of sexual maturation can be modified. Because there is little information about lighting programs in native turkey production in Iran, the aim of this research is determining the best lighting program for native turkey production.

The subtherapeutic use of antibiotics in animals has been under scientific and public scrutiny as antibiotic growth promoters (AGP) have been linked to the development of antibiotic resistance in bacteria, which poses a threat to human health (Smith et al., 2003). Short chain fatty acids such as butyrate are considered as potential alternative to AGP, In addition to its bactericidal activity; butyrate appears to play a role in development of the intestinal epithelium (Leeson 2005). Prebiotics (e.g. mannanoligosaccharides, MOS) are nondigestible feed ingredients that can selectively stimulate growth or metabolic activity of a limited number of intestinal microorganisms (Gibson and Roberfroid, 1995). This study was, therefore, conducted to investigate effectiveness of mannanoligosaccharides and butyric acid as potential alternatives to AGP in broilers.

The objectives of our study were to propose a growth curve and to develop a mathematical model to describe the body weight of pullet experiencing severe heat stress (42°C). Poultry producers who raise their own replacement pullets can control their pullet’s growth, condition and development. Many of the problems which occur during the early part of lay can be traced back to insufficient or improper type of body weight attained during the various stages of the growing period. In order to avoid these problems, the body weight of pullets must be controlled. Rearing conditions for pullets vary depending on environmental pressures and can affect growth rate. Without the basic knowledge of the flock grow-out, it is virtually impossible to understand and possibly solve problems which may later occur during the laying period. It must be kept in mind that once egg production begins, it is too late to solve problems resulting from growing period. The two most important criteria of pullet quality are uniformity within the flock and proper body weight at a specific age. Almost anything that adversely affects a pullet will usually be reflected in lower body weights and poorer flock uniformity. High ambient temperatures can be devastating to commercial pullet growth rate; coupled with high humidity they can have an even more harmful effect on proper and recommended body weight. Heat stress interferes with the poultry comfort and suppresses performance efficiency. In order to verify the effect of heat stress on pullet growth rate, many curve modelled, fitted and verified to proposed best one.

There has been interest in the enrichment of poultry meat with long chain n-3 polyunsaturated fatty acids (PUFA) as a means of increasing the low consumption of these acids by humans consuming western diets. There is some concern, however, that at high levels of consumption, n-3 PUFA may have detrimental effects on immune function. However, research to date shows that strong controversy surrounds this immunomodulation. The aim of this experiment was to determine the effects of dietary long chain PUFA on aspects of immune function in broiler chickens.

In comparison to 44% crude protein of soybean meal (SBM), the protein content of rapeseed meal (RSM) is about 35-40% and has a physiologically suitable amino acid combination in animal nutrition, but RSM contains nutritionally unfavourable substances such as glucosinolates, sinapin, tannin, phytate and non starch polysaccharides (NSP) (Kocher et al., 2000). Enzymes have the potential to be used in diets contain antinutritional factors that hinder nutrient availability. NSPs include cellulose, B-glucans, arabinoxylans, and pectins that may increase viscosity of digesta and cause a decrease in nutrient digestibility and performance of broiler chickens. Phytase activity from digestive secretions, some feed ingredients, resident bacteria, exogenous microorganisms, or both resident bacteria and exogenous microorganisms is present in the digestive tract of broiler chickens (Kornegay, 2001), but its efficiency at a practical level is very low. It is accepted that broilers lack sufficient levels of phytase activity to effectively hydrolyse the phytate molecule. Phytate-bound P is not well digested, so inorganic P is added to broiler diets that increased feed costs (Lescoat et al., 2005). The purpose of this study was to investigate the replacement value of SBM with locally grown RSM and two types of enzymes (NSP-degrading and phytase) on performance of broiler chickens.

In comparison to the 44% crude protein of soybean meal (SBM), the protein content of rapeseed meal (RSM) is about 35-40% and has a physiologically suitable amino acid profile for animal nutrition. However, RSM contains nutritionally unfavourable substances such as glucosinolates, sinapin, tannin, phytate and non starch polysaccharides (Kocher et al., 2000). Enzymes have potential to improve the nutrients availability of diets containing antinutritional factorst. NSPs include cellulose, B-glucans, arabinoxylans, and pectins that may increase viscosity of digesta and cause a decrease in nutrient digestibility and performance of broiler chickens. Phytase from digestive secretions, some feed ingredients, resident bacteria and exogenous microorganisms is present in the digestive tract of broiler chickens (Kornegay, 2001), but its efficiency at a practical level is very low. It accepted that broilers lack sufficient levels of phytase activity to effectively hydrolyse the phytate molecule. Phytate-bound P is not well digested, so inorganic P is added to broiler diets that increases feed costs (Lescoat et al., 2005). The purpose of this study was to investigate the replacement value of SBM with locally grown RSM and two enzymes (NSP-degrading and phytase) on the weight of carcass, some organs, and amount of blood-Ca and P of broiler chickens.

Food security is a global issue. General acceptance of the UN prediction that the world must increase food production by at least 50% in the next 20 years, and at least 100% in the next 40. Climate change and water availability will make this extremely challenging.

Climate change is characterised by uncertainty. But available economic assessments (e.g. Stern 2006) suggest that delaying action on emissions will lead to increasing global damage cost, with greatest incidence in poorer and vulnerable communities and sectors. There are thus efficiency and equity arguments for early coordinated global action on emissions reduction. In the UK the Climate Change Committee has been established to develop a route map for the “decarbonisation” of growth in all sectors including agriculture.