Feather pecking during rearing is difficult to identify and therefore often underestimated. However, as rearing conditions will affect the behaviour of adult hens, it is important or prevent feather pecking during rearing. This paper reviews the knowledge in the scientific literature on the effect of rearing conditions on injurious pecking. Factors such as stocking density and feeding strategies during rearing are known to influence feather pecking. Minimising the differences between the rearing and laying environment via a seamless transition is likely to make a flock less prone to injurious feather pecking. This can be achieved by providing perches and substrate for foraging and dust bathing during rearing, by providing facilities (e.g. litter trays) on perforated platforms during early lay and by focussing on early access to the range.

A requirement under humane slaughter regulation is that stunning methods should induce immediate loss of consciousness and sensibility. If the onset of unconsciousness is not immediate, the induction of unconsciousness with a stunning method should not cause in animals avoidable anxiety, fear, pain, distress or suffering. The duration of unconsciousness induced by a stunning procedure must be longer than the sum of time that lapses between the end of stun and the time to onset of death. Since the effect of a stunning method is momentary, the onus of preventing resumption of consciousness thereafter relies on the efficiency of slaughter procedure; i.e. the prompt and accurate severance of blood vessels supplying oxygenated blood to the brain. Electrical water baths and gas or controlled atmospheres are commonly used for stunning poultry under commercial conditions. The electrical waveforms (sine wave alternating current or pulsed direct current) and frequencies (Hz) employed to stun poultry and the amount of current applied to individual birds in a water bath stunner widely varies. Rationalisation of electrical variables is urgently warranted. Varieties of gas mixtures have been proposed or used for stunning or killing poultry in crates or conveyors however the bird welfare implications have not been communicated effectively to facilitate progress. This review deals with the efficacy of electrical variables used in the water baths and of slaughter methods, and the relative merits of different gas mixtures used for stunning or killing broilers.

Their higher production performance and feed conversion efficiency make today's chickens more susceptible to heat stress than ever before. The increasing proportion of poultry production in tropical and subtropical regions makes it necessary to reconsider the long-term selection strategy of today's commercial breeding programmes. Also, the importance of the potential use of Naked neck and Frizzle genes is accentuated. Nutritional strategies aimed to alleviate the negative effects of heat stress by maintaining feed intake, electrolytic and water balance or by supplementing micronutrients such as Vitamins and minerals to satisfy the special needs during heat stress have been proven advantageous. To enhance the birds' thermotolerance by early heat conditioning or feed restriction seems to be one of the most promising management methods in enhancing the heat resistance of broiler chickens in the short run.

When broilers are necessarily subjected to conditions of constant or cycling high temperatures, there is invariably consideration of changing diet formulation. Such changes may involve substitution of specific ingredients and/or alterations to nutrient levels in the diet. Aprimary concern is often the appropriate use of protein-rich ingredients and specifically their content of crude protein and amino acids. Broilers eat less at high temperatures, in an attempt to maintain homeothermy. Logically, diets will be fortified with protein and amino acids to counterbalance reduced intake. It is unclearif amino acids needs are altered, at high environmental temperatures, yet it is clearthat any such change in level orbalance is likely to be of lessermagnitude than change in feed intake. However, there is still controversy as to the direction of change for amino acids and protein under conditions of heat stress. There are specific concerns about the balance of certain amino acids, in particular arginine:lysine and also the source of any synthetic methionine added to correct apparent deficiencies. Balance of amino acids is described relative to pathways for polyamine metabolism.

We review the behavioural needs, priorities and preferences of laying hens for increased space, perching, nesting, foraging and dustbathing behaviour. Hens make full use of and may work to gain access to perches, however it is not yet known how perching ranks in comparison with otherbehaviours. Laying hens appearto have an instinctive need to perform pre-laying (nest-building) behaviour and have a strong preference for a discrete, enclosed nest site, for which they will work hard to gain access as oviposition approaches. Access to a nest site is a high-ranking priority for laying hens, preferred over food at this time. Foraging is a behavioural need, with peat, sand and wood shavings preferred substrates in choice experiments. There is no reduction in time spent foraging when a cost is imposed, nor when feed is freely available. Dustbathing is currently viewed as a behavioural need, as the extent to which hens value dustbathing is not known. Bird preferences for space are complex and confounded by interactions between group size and stocking density. There is some evidence that priority for space varies during the day and increases when the total space available to a group of birds is restricted, and that greater priority is given to space than to small group size. The presence of apparently purposeless behaviour, of high levels of aggression or redirected behaviours such as feather pecking and cannibalism are indicators that the housing system is not meeting the behavioural needs of the hens and hence is not satisfactory forbird welfare.

Enhancing meat production by genetic selection for growth has already produced 5-week-old broilers weighing more than 2 kg. As growth performance characteristics continue to improve and the time it takes to achieve market size decreases, the period of embryonic development becomes a greater proportion of the bird's life. Therefore, in parallel to genetic selection, other approaches, such as environmental manipulations in the embryo or in the early days posthatch, are becoming more relevant for increasing muscle growth and meat production.

Recently, we have shown that nutritional treatments, i.e., providing feed immediately posthatch, or environmental treatments, such as heat conditioning or monochromatic green-light illumination during the first days posthatch, increase muscle growth and breast muscle weight at marketing day. In all cases, the increase in muscle growth was due to changes at the cellular and molecular levels leading to increased satellite cell proliferation and differentiation.

The significant effects on muscle growth resulting from the treatments in the first days posthatch raised the hypothesis that muscle growth could be affected during the embryonic development. In experiments in which eggs were illuminated under monochromatic green light from embryonic day 5 (E5), there was a positive effect on embryo development and posthatch muscle growth. Further studies revealed that this enhanced muscle weight was due to increased satellite cell number and fiber synchronization during early days posthatch. Thermal manipulation at 38.5°C from E16 to E18 for 3 h/day had a delayed effect on satellite-cell proliferation and differentiation, resulting in enhanced hypertrophy of myofibers at market age.

In laying hens, cholesterol is primarily biosynthesized in the liver and incorporated into vitellogenin (VTG) and triglyceride-rich very low density lipoprotein (VLDL) particles, which are secreted into the bloodstream and subsequently taken up by growing oocytes via receptor-mediated endocytosis. VLDL and VTG are then intracellularly transformed into yolk, constituting ∼60% and 24% of yolk dry matter and ∼95% and 5% of yolk cholesterol, respectively. During the past four decades, research efforts directed toward reducing shell egg cholesterol content have centred on genetic selection or alteration of the laying hens’ diet with various nutrients, natural products, non-nutritive factors, or pharmacological agents. The present paper will provide a justification for low-cholesterol egg production, primarily in the context of the heterogeneity of response to dietary cholesterol in humans, and will review cholesterol metabolism in the laying hen, avian embryonic cholesterol needs, and genetic and nutritional approaches to chicken egg cholesterol reduction. A subsequent paper will provide a comprehensive overview of the use of non-nutritive dietary factors and select pharmaceuticals as egg cholesterol-lowering agents, and will discuss emerging strategies for lowering the cholesterol content of shell eggs.

Bioactive peptides are specific protein fragments that positively impact the body's function or condition and ultimately may influence health. These peptides are inactive within the sequence of the parent protein and can be released during proteolysis or fermentation. They may exert a number of different activities in vivo, affecting cardiovascular, endocrine, immune and nervous system in addition to nutrient utilization. Hen eggs have traditionally been recognized as an excellent source of protein, vitamins and minerals. Research in the past decade, however, has produced a substantial amount of evidence indicating that hen egg proteins and peptides may exert several diverse biological effects, above and beyond fulfilling basic nutritional requirements. Several biological activities have now been associated with hen egg proteins, including novel antimicrobial activities, immunomodulatory, anti-cancer, and anti-hypertensive activities, highlighting the importance of hen egg proteins in human health, and disease prevention and treatment. Continued research to identify new and existing biological functions of hen egg proteins and their derivatives will help to define new methods to further improve the value of eggs, as a source of numerous biologically active compounds with specific benefits for human and animal health, and secure their role in the therapy and prevention of chronic and infectious disease.

Turkey meat production growth has been very dynamic since the 1970s. Global turkey stocks increased from 100M. to more than 276M. birds in 2004, in the same period the production volume increased from 1.2 to 5.1M. t. The growth in numbers of turkey stocks and turkey meat production shows remarkable regional differences. Even though North and Central America are still dominating this branch of the poultry industry, Europe could gain market shares. A high regional concentration can be observed in the turkey industry. In 2004 the ten leading countries contributed 79% of the global turkey stocks and more than 89% to turkey meat production. The regional pattern of turkey meat trade has changed considerably. France became the leading exporting country in the1980s; in 2003 the top three importing countries were Mexico, Russia and China. The regional concentration in turkey meat trade is also very high, in 2003 the ten leading countries contributed about 91% to the global export and 72% to the import volume. A major influencing factor behind the changing regional pattern of production and trade has been the development in the per capita consumption of broiler and turkey meat.

This paper reviews the contribution that eggs can make to the human diet and considers the additional benefits that can be derived from modifying the egg's nutritional profile and in particular the egg's fats and antioxidants. Attempts to modify the egg's fat component have tended to focus on the means by which the cholesterol level in the egg may be reduced orthe ratio of n-3 to n-6 polyunsaturated fatty acids (PUFAs) manipulated. The cholesterol content of the egg has been lowered by either reducing the mass of the yolk relative to the egg (i.e. a non-specific reduction) or by using feed additives such as beta-cyclodextrin that have a specific effect on the cholesterol content of the yolk. The ratio of n-3:n-6 PUFAs in the diet is important not only because of their role in energy metabolism and biological membranes but because they affect eicosanoid metabolism, gene expression and intercellularcommunication. Eggs produced from hens receiving conventional feeds tend to be relatively high in n-6 PUFAbut dietary manipulation can be used to either increase the amount of the n-3 PUFAs directly (using fish oil) or indirectly by increasing the levels of the precursor n-3 PUFA by feeding alpha-linolenic acid (ALA) in the form of linseeds, flaxseeds or similar. Of particular interest is the n-3 PUFA docosahexaenoic acid (DHA). The relatively high degree of unsaturation makes this PUFAsusceptible to oxidation during storage and cooking but this can be resolved, at least in part, by enriching the egg yolk with antioxidants such as vitamin E. Apart from reducing the rate of PUFAoxidation, enriching the level of antioxidant in the egg can also enhance levels of antioxidants in the consumer. The effect on the consumerof consuming modified and conventional eggs is considered.

A review of the literature regarding Low Protein diets (LCP) for broilers reveals that by using crystalline amino acids, dietary CP could be reduced in each phase safely by a factor of 10% (a figure fairly consistent with turkeys but quite low with that found for ducks and swine) from the respective NRC (1994) levels; the calculated minimum dietary CP levels thus appeared to be 20.7, 18.0, and 16.2% respectively for 0-21, 21-42 and 42-56 days of age. It is, however, noted that the magnitude of protein reduction, without affecting the growth performance of broilers, could have been increased depending upon the EAA concentration and balance of LCP vs. control-CP diets as well as the response criteria used (gain vs. composition of gain). Further reduction in dietary protein results in depressed live/carcass yield in almost all cases. Depressed feed intake appears partially to explain the negative effect of LCP diets in some cases. Addition of NEAA-like glycine above the current NRC recommendations has shown partially to alleviate the negative effect of LCP diets indicating imprecision of our knowledge about NEAA (like glycine, serine and proline etc) requirements of broilers under these conditions. The dietary NEAA/EAA ratio seems to be an important, though poorly understood, factor in defining the performance of broilers fed on LCP diets. It seems that regardless of the absolute amounts of dietary amino acids, performance tend to be depressed when NEAA/EAA ratio is decreased from 50/50; thus the NEAA level of about 50% of protein seems “minimum” state of adequacy. More work is needed before a precise role of the ratio of nitrogen coming from NEAA vs. EAA is proposed. A wider NE:ME in LCP diets seems to explain the higher body fat accretion on these diets; more work on how dietary NE:ME ratio modulates the growth performance of broilers, and how it interacts with different genetic stocks (lean vs. fat lines) is warranted.

The microflora of the digestive tract of poultry is still incompletely known. Microbial populations of varying size and complexity occur throughout the digestive tract and the highest and most complex floras are found in the crop and the caeca. The upper part of the digestive tract is predominantly settled by facultative anaerobes, whereas the caeca are mainly the site of obligate anaerobes. The types, numbers and metabolic activities of the organisms are affected by numerous factors such as individual, animal age, environment, and diet. Bacteria produce various metabolites that can be useful or detrimental to the host. Interactions between bacteria and the gastrointestinal epithelium lead to various structural and functional modifications of the digestive tract. Bacteria can impair lipid digestion and may modify carbohydrate and protein digestion. They cause an increase in energy and amino acid requirements. They have a negative effect on vitamin nutrition. Beneficial bacteria can protect birds against pathogens through a competitive exclusion process. Moreover, the flora is involved in the development of the intestinal immune system. Overall, bacteria have a negative effect on bird growth. They may also have an effect on meat and egg quality. Improved knowledge of the microflora of the digestive tract and its consequences may contribute to its control and beneficial use for birds as well as breeders, consumers and the environment.

Proper cleaning and effective sanitation is an essential component of processing poultry, as it contributes significantly to the prevention of product contamination with microorganisms that cause food-borne disease and spoilage. Rapid expansion of production volume, increased further-processing and introduction of diverse ready-to-cook and ready-to-eat products, sophistication of the processing equipment, implementation of HACCP and microbial finished-product standards, and, more importantly, expensive product recalls have necessitated greater control over the cleaning and sanitation process.

A sanitary process should effectively protect raw and/or cooked products from physical (i.e. metal, plastic, bone, packaging materials etc.), chemical (residues of cleaning and disinfection chemicals, lubricants, coolants etc.), and biological (food-borne pathogens and/ortheirtoxins) hazards. In spite of this, many hazards continue to find their way into the processing environment and ultimately into the finished products. Microorganisms are naturally introduced into the poultry processing environments in high numbers with the live birds and, when the conditions are suitable, form growth niches by actively multiplying within the system.

It is generally accepted that processing equipment should not be a direct orindirect source of microbial contamination. Many regulatory and advisory bodies have introduced hygienic design and processing guidelines. This presentation will review the recently introduced sanitary processing equipment design principles and equipment checklist by the American Meat Institute.

Aplant designed, equipped, operated and maintained with internationally accepted hygienic and sanitary standards will produce safe and wholesome poultry products forthe consumer.

An increase in the production of palm kernel meal (PKM) coupled with the concern for continued availability of conventional feedstuffs in some parts of the world has led to research to establish the maximum inclusion level of palm kernel meal in broiler diets. The results suggested that palm kernel meal has no anti-nutritional properties and thus its inclusion is safe up to at least 40% in the diet, provided the diet is balanced in amino acids and metabolisable energy. Although feed digestibility is decreased due to high dietary fibre when PKM is included in the diet, the feed intake is increased. This makes total digestible nutrient intake relatively high. β-mannan is the main component of palm kernel meal non-starch polysaccharide (NSP). Both mannose and manno-oligosaccharides have been reported to act as prebiotics. The inclusion of palm kernel meal in the diet improves the immune system of birds and reduces pathogenic bacteria and increases the population of non-pathogenic bacteria in the intestine. These two benefits should be considered as strong recommendations for using palm kernel meal in broiler diets, particularly in palm kernel meal producing countries, not only forincreasing bird productivity but also to improve chicken health. Selective enzyme addition increases feed efficiency and digestibility as well as decreasing the moisture content of faeces.

Optimal utilisation of limited phosphate resources in animal feeding requires detailed knowledge of both the requirement for available phosphorus (P), and the availability of P from relevant feed ingredients. In growing ducks, the P concentration of gained body weight and the inevitable P losses voided determine the requirement for available P. The concentration of available P needed in the diet then depends on the feed conversion ratio. Plant and mineral feedstuffs contribute to the available P content of the diet depending on their respective availability. This review summarises the literature on P nutrition in ducks with regard to factors affecting P requirement and considerations of P availability, including the use of microbial phytase. Most of the published data refer to the Pekin duck. The P content in body weight gain is 5.0–5.5 g/kg in young ducks, and it probably decreases with age. The ratio of Ca to P in body weight gain is about 1.8:1. Inevitable P losses are not yet quantified and can only be estimated to account for 1 g/kg of feed intake. Availability of P from plant-based diets without P supplements and phytase ranged between 28 and 49%. Availability of P from different mineral sources ranged between 77 and 100%. Microbial phytases were efficient in improving the availability of P from plant-based diets. A simple model is presented, which allows flexible calculations to be made of the necessary P concentrations in the diets for ducks. The most efficient tool for reducing the use of P sources is the frequent adjustment of the dietary P content during the growth period. Data from growth studies indicate that the suggestions made herein are sufficiently safe for application in Pekin duck feeding.

The poultry industry in Kuwait is one of the leading food industries in the country. It consists of several poultry companies that vary between large, medium and small size poultry producers. The majority of poultry production concentrates on chicken meat and eggs, due to consumers' demand. An estimated 60% of the local broiler production is marketed live, 5% chilled and the rest as frozen. The poultry industry in Kuwait is moving towards production of specialty food such as eggs enriched with omega-3-fatty acids which, it seems, will take part of the market share in the future. Per capita consumption of poultry meat in Kuwait reached 63.3, 61.2, and 60.8 Kg in the years 2004, 2005, and 2006 respectively. Average per capita consumption of poultry meat before the invasion by Iraq was 22 Kg and after liberation per capita consumption increased. Before the invasion, chicken meat was considered as the second most popular meat consumed after lamb and mutton. However, after liberation, red meat consumption was reduced in the years 1996 to 2002. This could be due to concern about the so-called ‘Mad Cow’ disease that shifted consumer preferences from red meat to poultry. In addition, increased consumers' health awareness and presence of the coalition troops in Kuwait and near Iraq increased the demand for poultry meat. Since local producers supplied only 47% of the poultry meat and 55% of table eggs consumed and the remainder of the local poultry consumption imported from other countries, more development and improvement in production is needed in the industry in order to gain confidence of their consumers and increase their share in the market.

Embryonic loss occurring in the first week of the incubation is termed early embryonic mortality. Environmental, technological and genetic factors can be responsible forits appearance. The examination of genetic background of embryonic death is justified when the breeding and hatching technological parameters are optimal. Disposition of early embryonic mortality can be inherited and it can accumulate in a stock, which will finally deteriorate its fertility indices. Although the heritability value of reproductiveness is poor, h2=0.1−0.2, even so, during the selection still should be considered. This paper offers a short review on the special features of early embryonic development in poultry and examination methods forpossible genetic background of early embryonic abnormalities and mortality. The application of cytogenetical and embryological methods may be of major relevance in the improvement of the reproduction traits of poultry species.

If proteins are the functional units of almost all biological processes, the proteome represents the set of proteins expressed in a cell at a given time and for given conditions. Because muscle is mainly composed of water and proteins, it seems evident that proteome analysis can give much information on structures and functions of proteins involved in several mechanisms which determine meat quality. This paper aims to present the most classical techniques (i.e. sample preparation and protein solubilisation, protein separation by 2-DE or SDS-Page, protein detection and quantification, computer analysis of 2DE-pattern and finally protein identification) that are currently applied to analyse the proteome.

Proteomic study related to meat quality are somewhat limited, especially in poultry, but some results are presented to illustrate how proteomic approaches can bring a new point of view on new or already known meat quality problems. It is the case in mammals where meat tenderness had been given a new highlight with proteomic study but also in turkeys where new hypothesis for explaining PSE meat syndrome can be developed from proteomic analysis. Some studies have also reported interesting results in muscle growth and development in chickens.

Meat quality is a complex problem which includes several factors of variation such as genetics, handling of animals during production, transportation and slaughter and also the handling of meat during product processing. Proteomic tools can give a new point of view on these problems and help the biologist to understand and finally resolve it.

This study attempts to identify the poultry meat farmers' objectives of production, analyse their socio-economic characteristics, determine the optimal farm size and prioritize the constraints to achieving the enterprise objectives. Taking Osun State of Nigeria poultry meat farmers as a case study, data on poultry meat business enterprise objective(s), socio-economic characteristics of farmers and farms, quantity and prices of inputs and output, and constraints to production were collected. Data were analysed using descriptive and inferential statistics, regression technique and importance indices.

From the profit function analysis, the profit maximizing output level was 1034 birds which was higher and more profitable than the mean output level (765 birds) that farmers operated. As many as 88 percent of the farmers sampled produced below the profit maximising level of output. Producing at the average profit maximizing level of output (223 birds) resulted in lower level of output and lower total profit than the mean and profit maximizing output levels. About 90 percent of the farmers produced higher than average profit maximizing output level. The constraints that limit farm size and which could affect sustainability of the enterprise were irregular demand of poultry meat, poor feed quality, high mortality rate and feed price instability in that order. These constraints, if addressed, would lead to increase in poultry meat supply to meet local demand and export.

This study investigated the linkages between socio-economic variables and the efficient marketing of poultry feeds in Delta State. Primary data collected from 100 randomly selected respondent poultry feed marketers, using structured questionnaire/interview schedule, were analysed using descriptive statistics and pairwise correlation model. The study revealed that marketers' years of experience (0.89) and improved packaging (0.62) have positive and significant relationship (linkages) with efficient marketing of poultry feeds; while distance between source of procurement and selling centre (−0.74) and associated cost of transportation (−0.98) have negative relationship (linkages) with the efficient marketing of poultry feeds. Price per bag and poor road network (market access condition) were the major problems affecting efficient marketing of poultry feeds in the study area. Implication for extension officers participation in poultry feeds marketing was emphasized.