The population of the Middle East and North Africa (MENA) region was 432 million in 2007 and it is estimated that in 2050 this figure will rise to 692 million inhabitants. The poultry industry in the MENA region depends heavily on imported soybeans and soybean meals. About 8.5 million metric tons of soybean meal (SBM) are needed for the production of poultry meat and eggs every year, based on the production of about 8.2 million tons of poultry meat and 3.7 million tons of eggs. Poultry feed prices are consistently increasing because of dependence on imported soybean meal. Hence, it is essential to find sustainable alternative protein sources. Several countries in the region produce sizeable amounts of oil seed meals that can partially or fully replace soybean meal in poultry rations. Nearly 5 million tons of cottonseed meal (CSM), peanut meal, sesame meal, sunflower meal and rapeseed meal are produced yearly in this region. The neighbouring countries of India, Pakistan and Sudan produce over 36 million tons of these meals. This study focused on these five meals in relation to amounts produced, quality and possible levels of use in various poultry rations. Data will be presented on availability, constraints of these meals as replacements for SBM, economic feasibility, and methods of improvement for possible utilisation at higher levels. Oil seed meal digestibility, quality, naturally occurring toxins, antimetabolites, mycotoxins, nutrient imbalances, and prices play a major role in determining the use of these meals for the production of poultry meat and eggs.

In the past, trace minerals have been inadequately considered by poultry nutritionists, as demonstrated by the scarce availability of literature. The practice of using high safety margins between requirements and dietary concentrations and the relative low cost of these essential minerals are possible reasons for this. Environmental considerations and regulations limiting trace mineral supply and improvements in analytical methods to detect putative contaminants in mineral sources have led to a need to a re-examination of trace mineral requirements. In addition, new knowledge regarding trace mineral roles in bone metabolism, anti-oxidant status, homeostatic regulation, product quality, immunology and the development of novel trace mineral sources have favoured, for the past 15 years, interests in optimising trace mineral nutrition considering other parameters than solely the bird performance. This review analyses the role of essential trace minerals (mainly Zn, Cu, Fe, Mn, I, Se) in broiler and laying hen nutrition. This work aims to highlight the evaluation of trace mineral requirement, the bioavailability of trace mineral sources, especially in regards with phytate antagonism, and the main functions of trace minerals in egg, eggshell and meat quality. The impact of trace minerals on the environment (toxicity to plants and microorganisms) is considered and nutritional means to reduce the risk of environmental contamination will be explored. Finally, the possibilities of poultry product's enrichment in some trace minerals for the benefit of human health will be explored.

Newcastle disease is one of the most important diseases of poultry with wide distribution and high fatalities. An infection with a virulent strain can cause up to 100% fatality in a susceptible flock, with devastating economic losses. In-feed antibiotics are not directly effective against Newcastle disease virus (NDV), but they may assist in prevent associated production problems. With in-feed antibiotics being controlled or banned, prebiotics, particularly those sourced from spices, and probiotics have been investigated as potential alternatives for maintaining seroconversion in poultry vaccinated against NDV. Certain prebiotics have a positive effect on anti-NDV antibodies but using spices as sources of prebiotics gave no clearly defined results. Garlic extract was reported to increase the mean haemagglutination inhibition (HI) titre of NDV by 0.6 after two weeks of supplementation, increasing titres by 4.0 in the vaccinated group compared to an increase of 3.4 in vaccinated unsupplemented group. However, onion-based compounds did not improve anti-NDV antibodies. The majority of studies have found that probiotics improved antibody levels and seroconversion to NDV vaccines in poultry. A commercial probiotic, containing a mixture of Bacillus species and Saccharomyces boulardii when used at a concentration of 100 g/ton was found to significantly increase the anti-NDV titre (log2) from 5.00 to 5.50. Another commercial probiotic, consisting of a combination of bacteria, reduced mortality by 6.6% at a concentration of 1 g/kg. Additional studies are needed to define the conditions and forms in which both the pre- and pro-biotics work best with respect to NDV control.

Oligodeoxynucleotides (ODNs) containing cytosine-phosphate-guanosine sequence (CpG) is considered as an immune stimulator when it is fed to animals. These synthetic molecules mount different immune responses in the animals including mice, chickens, ducks, dogs and horses. CpG ODNs induce specific antigenic immunity against co-administered vaccines and are well tolerated in healthy individuals and are capable of stimulating toll-like receptors (TLRs) such as TLR-9 to activate innate immunity. The CpG ODNs can be used as an adjuvant in different vaccines synthesised specifically for poultry diseases caused by viruses and bacteria. In chickens, CpG ODNs stimulate TLRs involved in humoral immunity. CpG ODNs have been used as mucosal vaccine adjuvants against several pathogens, including avian influenza and Newcastle disease. The CpG ODNs function to protect the chickens from Newcastle disease by producing plasma dendric cells (pDCs) which ultimately produce interferons (INFs). The inoculation of CpG ODNs along with the cationic microparticles and DNA vaccine for infectious bursal disease virus result in the influx of T cells and a reduction of antigen load. When CpG ODNs are used against avian leucosis, they result in significantly higher antibody titres. In many other vaccines e.g., infectious laryngotracheitis, infectious bronchitis, herpes, viral enteritis, Marek's disease virus, E. coli and Salmonella spp. including CpG ODNs exhibit immunostimulatory effects. In conclusion, CpG ODNs may be used as effective adjuvants in viral, bacterial and parasitic vaccines in poultry.

It has been established that embryogenesis is accompanied by the intense production of nitric oxide (NO). Based on available data, the rate of NO production is roughly equal in all embryos of the same poultry species. However, the rate of NO oxidation to nitrate in embryos of meat breeds is higher than in embryos of egg breeds. In broiler embryos about 90% of all produced NO is oxidised to nitrate. In embryos from egg breeds only several per cent of the NO oxidised to nitrate and the other NO is stored in the embryonic tissues included in NO donors. The intensity of NO oxidation in bird embryo is not depended on sex, age of the layer and feeding regime. Intensity of oxidation varies by no more than 10% within a breed strain or cross. Breeding to increase meat productivity is always associated with an increase in the intensity of NO oxidation in the embryo. There is no direct relationship between the increase in NO oxidation and the live weight gain. It can vary from hundreds of percent to several percent depending on the breed. Moreover, morphological differences between breeds with high and low intensity of embryonic NO oxidation are manifested only after hatching, as synthesis of NO is much lower than in the embryo. It has been presumed that NO oxidation is associated with the synthesis or activation of the factor(s) involved with enhanced growth of meat tissue. This is predetermined genetically and can be partly induced by exogenous stimulants, such as green light. The rate of embryonic NO oxidation can therefore be a useful criterion in practical selection of poultry and in the evaluation of growth enhancers acting at the embryonic level.

Origanum vulgare is a natural, less toxic, residue free feed supplement for poultry when compared to other synthetic ingredients. It contains key bioactive components, including as thymol and carvacrol. O. vulgare as a poultry feed supplement has had an antimicrobial, antioxidant, antiviral, immunomodulatory and antiparasitic effect. The potential advantages of utilising oregano extracts, in poultry diets include improved feed intake and feed conversion, enhanced digestion, expanded productive performance, down-regulated disease incidence and economic losses. From the available literature, average inclusions of oregano essential oil up to 600 mg/kg in broiler diets increased body weight gain. Using 1% oregano oil in broiler diets improved feed conversion ratio and feed utilisation. Moreover, oregano can induce a marked improvement on the intestinal microbiota and ileal villus height of broilers when combine with attapulgite by ratio 15 mg/kg of oregano. Broilers fed 300 ppm oregano oil in their diet display higher IgG titres relative to those reared on control (without supplementation) diet. Including 240 mg oregano supplementation per kg diet appears to give an optimum level for protecting broiler chickens from C. perfringens infections. Bioactive components extracted from O. vulgare parts could be used in poultry diets levels of 10 to 30 g/kg. This review includes information on the use of O. vulgare and its derivatives in poultry nutrition. To maximise the overall productivity of poultry, oregano may be used as a natural alternative to antibiotics and drugs due to the absence of side effects and residues.

Pekin ducks are easily reared in a wide range of conditions. As waterfowl, the growth, digestive system and visual perception of Pekin ducks are different to chickens. Generally, ducks are raised for meat production. The fat content as well as the myoglobin and haemoglobin content of duck meat are higher than that of chicken meat. In duck rearing, both the fattening performance and the quality of meat are important from the consumer's and the producer's point of view. Different rearing systems are used for ducks which affect the welfare, fattening performance, quality of meat and economics of the products. The aim of this review is to discuss the effects of different rearing systems used for Pekin ducks on fattening performance and quality of meat.

It is known that glutathione peroxidase (GSH-Px) belongs to the first and second levels of the antioxidant network and is involved in the regulation of many important cellular pathways including maintenance of the redox balance and signalling. In poultry the GSH-Px family includes four Se-dependent forms of the enzyme, however only GSH-Px1 and GSH-Px4 are well characterised and have received substantial attention as important enzymes participating in chicken adaptation to commercially-relevant stresses. The aim of this review is to analyse the current data on relationships between various stress conditions and the GSH-Px activity in poultry with special emphasis to selenium status and nutritional supplements. Indeed, the published literature indicates that there is a range of different nutritional (Se supplementation, antioxidants, plant extracts, probiotics, drugs, mycotoxins) and environmental (temperature stress, transportation, disease) factors modulating GSH-Px activity and/or expression in different tissues from poultry. These inducible enzymes are involved in adaptation to stress and Se supplementation in optimal concentrations whereby form is key for antioxidant system maintenance under stress conditions in commercial poultry production.

Echinacea purpurea is one of the most widely used medicinal herbs that is of interest to animal scientists due to its valuable immuno-stimulatory and anti-inflammatory properties. It is thought that it activates the immune system through stimulating T-cell production, lymphocytic activity, phagocytosis, cellular respiration and inhibiting the secretion of the hyaluronidase enzyme. Chicoric acid (CA) is a major active constituent of Echinacea purpurea. The CA content in roots ranges between 16.80-24.30 mg/g which has gained a lot of renown due to its promising bio-activities. CA has shown to simulate growth promoters and have antioxidant, anti-diabetic, anti-inflammatory, anti-HIV, anti-bacterial, hypoglycaemic and hepatocyte protective properties. There have been very few studies relevant to CA and its use in poultry diets. Previously published studies have included pharmacological and nutritional investigations in the poultry industry. CA could be used as an alternative to antibiotics, and may improve meat quality and health status in broiler chickens.

Artificial insemination (AI) technology use in poultry production has enabled the rapid dissemination of genetic material from a small number of superior males to a high number of females. Excellent fertility in poultry can be obtained by AI compared to natural mating. Successful application of this technique needs good quality semen that should be inseminated very close to the sperm storage tubules in the female to obtain the optimum fertility in chicken. Since the 1950s, AI has been used in commercial poultry production, initially in Israel and Australia, followed by the USA. Doses of spermatozoa required for AI increases with storage time or that obtained from aged bird. The average volume of semen is between 0.05-0.50 ml in light chicken breeds and 0.1-0.9 ml in heavy males. In light turkeys, volume is 0.08-0.30 ml, whereas in heavy-weight males it is 0.1-0.33 ml. Quality evaluation of semen gives an indication of the male reproductive potential and is the major determinant of fertility and subsequently hatchability of eggs. Semen from cockerels contains between 3-7 billion sperm cells/ml. Among the several factors that influence the semen quality, sperm motility is a primary determinant of fertility in domestic fowls; however, visual examination of semen cannot be ignored for successful AI under field conditions. Dilution of low and viscous volume of avian semen is essential for handling and storage, and chicken semen typically requires a two to three-fold dilution. Collected samples should be preserved at 2-8°C for avian species, ideally with turkey sperm stored at 4-8°C, and chicken semen at 7-8°C for good fertility. Currently, the technique of AI in most of the poultry species is well developed; however, there is a need for successful development programme of this technique in non-domesticated birds to assist in creating viable, self-sustaining populations of critically endangered species.

The purpose of this review is to review the current state and achievements in poultry production in Serbia and worldwide, primarily the EU. Particular emphasis is placed on impacts of different rearing system, i.e. housing and fattening, on the production and the quality of the poultry meat and eggs and, simultaneously, on the welfare of poultry and environmental protection according to EU standards. According to the latest available data, total number of poultry produced in Serbia in 2015 was 17,450,000 units and production of meat amounted to around 86,000 t, while consumption was 12.12 kg per person. Egg production in 2015 was approximately 1.7 billion eggs, which is around 202 eggs per hen. A total of 13.1 million tons of poultry meat was produced in EU in 2015. It is evident from the literature that the poultry production in EU and worldwide has undergone significant changes, and clear criteria have been established to improve the quality of the products (meat and eggs), to guarantee the safety of the food, to protect the environment, and to ensure animal welfare in line with the relevant ethic norms. For these reasons, many countries within EU and worldwide, including Serbia, attach importance to housing systems for laying hens, with particular concern for animal welfare. Alternative housing systems (floor, aviary, free range and organic production) are increasingly used in the production of poultry meat and eggs instead of conventional systems. This is because it is considered that alternative housing systems may have positive effect on the productive traits of the poultry and, consequently, on the production of the quality organic meat. Furthermore, it is evident from research that pure (indigenous) breeds and strains are given growing importance in the production of organic meat and eggs in semi-intensive, semi-extensive and even in extensive rearing systems.

Anthocyanins are flavonoids widely spread in various plant species as a major phyto-pigment. In recent years, interest in using anthocyanins as a feed ingredient has increased markedly owing to their health and other benefits. Anthocyanins possess various pharmacological properties, including anti-inflammatory, immunomodulatory, anticancer, antidiabetic, neuroprotective, anti-obesity and antioxidant effects. Dietary consumption of anthocyanins has revealed benefits in animal performance. Little is known about health-promoting effects of anthocyanins in avian species, but anthocyanin-rich dried fruits have shown positive effects on certain pathological conditions and health promoting markers in human and other animals. This review aims to gather information regarding health benefits of anthocyanins and highlight therapeutic and potential health beneficial effects of anthocyanins for poultry. Additionally, it explores these biologically important flavonoids as alternative ingredients in poultry feed to replace synthetic nutrients and medicines. The available literature reports studies involving use of anthocyanins focused on human, mice and in vitro models. However, there is a need to explore mechanism of action at molecular level to understand potential beneficial effects of anthocyanins in avian species.

Flavonoids are natural compounds derived from different types of vegetables, fruits, and medicinal herbal plants. Hesperidin, a flavanone (a class of flavonoids) glycoside is found abundantly in citrus fruits such as oranges, lemons tangerines and limes and is known to possess significant benefits, such as anti-inflammatory, anti-stress, antioxidant, growth promoting, anticancer and immunological properties. Hesperidin enhances mucosal and humoral immunity by increasing intestinal intraepithelial lymphocyte numbers, lymphoid organs (thymus, spleen and bursa) indices, as well as improving anti-avian influenza and anti-Newcastle disease antibody titres in poultry. In addition, hesperidin is a strong chain-breaking antioxidant that provides potent cellular antioxidant defence against the damaging effects induced by peroxide hydrogen. As a natural antioxidant, hesperidin could help mitigate heat stress during summer by decreasing heterophil-to-lymphocyte ratios, and quenching reactive oxygen species generated by summer heat stress. The aim of this review was to elucidate the biological effects and health benefits of hesperidin as an alternative of synthetic immune boosters and growth promoters in poultry diets.

Factors involved in light management of poultry include source, intensity, duration, uniformity and wavelength (light colour) of light. Research trials have examined the effects of short (blue and green) and long wavelengths (orange and red) on animal welfare, body weight gain, and egg productions in chickens, quail, turkeys, geese and ducks. Blue or green illuminations have a positive effect on body weight and red or white are beneficial to the production of eggs in chickens and quail. During the pre- and post-maturity periods of turkeys, blue light was preferred in the pre-maturity period, whereas the red or white light was better for the post-maturity period. Any noticeable change has not been observed within the body weight gain among the geese under different coloured light; whereas white-coloured light has played an important role in their egg production and semen quality. Positive results have been seen for body weight gain by exposure to red and white light in ducks. The available literature shows that different wavelengths can have positive or negative effects on welfare, body weight gain and egg production of the poultry.

In the last few decades, there has been growing interest in the use of agricultural wastes as feed ingredients in poultry diet to maximise their potential output. Many wastes of the agroindustry (e.g. citrus, grape, pomegranate and apple processing) have significant antioxidant properties, due to their bioactive compounds (polyphenols, flavonoids). It has been reported that citrus and grape wastes can be successfully included in broilers diets up to 3%, which increases carcass and meat yield and reduces abdominal fat (by 10% on average). Pomegranate can be included up to 2% supplementation and is associated with improved feed efficiency (by 12% in broilers). Apple by-products can be formulated up to 5% in diets for meat-type broilers and up to 10% in laying hens diet to reduce oxidative stress. Therefore, the application of these by-products in poultry diets could combine the positive effects of improving the qualitative characteristics of animal products as well as human health with reducing concerns related with their disposal into the environment. In this review, the findings on the effects of some agricultural wastes, from typically-cultivated products originating in Mediterranean and Middle East regions on poultry performance, carcass characteristics, immune response, plasma constitutes, intestinal microbiota and enzyme activity are reviewed and discussed.

Several techniques have been developed for the preservation and improvement of genetic resources to maintain genetic diversity. Among those techniques, semen cryopreservation is thought to be the best and successfully applied by dairy and beef industries, but so far, it has not been established in the poultry industry. This is because poultry sperm cells have a unique shape and membrane fluidity, differing from those of mammalian sperm. Also, poultry sperm membranes contain higher quantities of polyunsaturated fatty acids than mammalian sperm, and hence may require more antioxidant protection. Due to the peculiarity of poultry sperm cells, commonly used cryoprotectants for cryopreservation have a contraceptive or toxic effect. This renders the fertility of frozen poultry sperm to become highly variable and not reliable enough for use in commercial production or preservation of genetic resources. The average fertility of frozen/thawed poultry sperm ranges between 2-80%. Therefore, this paper reviews the possible reasons for the lower success of poultry sperm cryopreservation.

The use of non-starch polysaccharide (NSP) enzymes has increased in recent years with most of the growth coming from the market segment which uses non-viscous diets. A variety of product choices are available to the feed industry. These range from mono-component, single enzymes, to cocktails of more than one activity, to so-called ‘complex’ enzymes, displaying, in addition to the main activity, several non-targeted (i.e. quality controlled or assured) activities within one product. The relative abundance of the substrate or the number of substrates presented by a given diet may not be viewed as the sole criterion for the fitness of an enzyme solution. An argument can be made that NSP enzymes should not be considered as classical digestive enzymes and any response may not be regarded simply as a function of the extent of in vitro or in vivo substrate hydrolysis. The idea of having additional non-NSP or NSP activities to ‘strengthen’ a xylanase response, as well as the notion ‘complex diet needs a complex enzyme’ appear to lack sufficient scientific backing. Measures based on alternative responses e.g. gut morphology, nutrient or energy digestibility, gut-flora and its metabolites or fermentation profiles, are useful in developing a wider understanding of the phenomenon but require careful interpretation as the stand-alone criteria of usefulness of an NSP enzyme. Performance data is always the ultimate judge of the efficacy of a feed enzyme. This review addresses the practical question of selecting an NSP enzyme. The aim is to discuss the data supporting some of the common views held in the industry today, and how these views significantly influence the process of selecting an NSP enzyme for commercial in-feed application.

Royal Jelly (RJ) is product from bees that is used to feed larvae in the hive as well as a main nutritional source for the queen honey bee. It has various important biological activities including as an antioxidant, immunomodulatory, anti-inflammatory, antimicrobial, cholesterol-lowering, and growth promoter activities and has the ability for inhibition of certain enzymatic degradation. It can be used for the improvement of growth performance, gut health and quality and safety of animal products in poultry due to its antioxidant and immune modulating properties. The antioxidant activity of RJ is mainly due to the presence of polyphenolic compounds. It is an excellent source of B and C vitamins and folic acid. The mineral profile of RJ is useful as it contains major macro and micro minerals. Studies conducted on supplementation with RJ in poultry diets have shown a significant increase in body weight, egg production, and immune levels and is especially useful in organic production. Supplementation of RJ at the level of 10 and 15 mg/kg in layer diets positively influenced egg weight (by 5.0% and 4.8% respectively), egg production (10.5% and 11.0% respectively), weight gain of hens (7.0% and 6.5% respectively) and yolk pigmentation (9.5% and 9.7% respectively). Total leukocyte and erythrocyte counts in the diet containing 200 mg/kg RJ were significantly higher than the diet contained 100 mg/kg or the unsupplemented control group. However, the heterophil/lymphocyte ratio and heterophil percent were reduced in RJ-fed groups. Supplementing poultry diets with RJ offers an opportunity to maximise profit from safe and high quality poultry production.

The following review covers current and classical knowledge regarding the positive effects of organic acids on phytase activity and phytate P availability in broiler chickens. Despite the improvements achieved for phytase stability under gastrointestinal conditions, intrinsic characteristics of phytic acid, dietary components and the digestive tract favour phytate formation and, consequently, inhibit the degradation of phytic acid and other inositol phosphates by phytase. Organic acids, more frequently citric acid, have been shown to decrease phytate establishment and enhance phytase activity. When supplemented alone, citric acid increased P retention by 16 to 34% and phytate P retention by 105% in broilers. When combined with phytase, 3.27% better tibia ash has been reported. From the available data, it appears that combined use of phytases and organic acids deserves greater consideration in modern poultry nutrition.

Heat stress is one of the most important physiological factors challenging poultry production throughout the world especially in tropical and sub-tropical countries. Oxidative stress induced by heat stress not only compromises productivity and performance but also results in morbidity and mortality losses leading to the economic burden for poultry producers. It reduces the shelf life of poultry product in addition to poor meat and egg quality. Recently, a trend towards using phytochemicals derived from natural sources with potential antioxidant activities has increased. Lycopene is a predominant carotenoid pigment which is universally found in fruits and vegetables, with tomatoes and their products being key sources. Several in vivo and in vitro studies have suggested that lycopene is a powerful antioxidant compared to other carotenoids. Supplementation of tomato (Solanum lycopersicum) derived lycopene revealed numerous health promoting activities in poultry birds, such as anti-oxidant, anti-inflammatory, immunomodulation, improved performance and better meat as well as egg quality. Lycopene maintains oxidative balance in birds through various ways including serving as a free radical scavenger, inhibiting signalling pathways and activating host antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT). The aims of this current review are to summarise mechanisms of action through which lycopene quench reactive species and maintain oxidative balance, highlight the potential role of lycopene as a natural antioxidant agent for poultry industry and examine the benefits to poultry producers when using this natural antioxidant on commercial basis in poultry diets to alleviate the adverse effects of heat stress.