Infectious diseases of poultry are mostly associated with severe economic losses. Many of these diseases once re-emerging or introduced into a geographic area, can explode into an epidemic and may have a significant negative effect on international trade. Beside general control approaches like biosecurity, improvement of rearing management, monitoring, and vaccination several governmental measures on control of poultry diseases were adopted in European countries.

Eradication policy and killing of animals for disease control purposes are commonly applied in cases of suspicion or confirmed outbreaks of emergency diseases, outbreaks of diseases with a considerable public health and/or economic impact and in case of possible irregularities during the intra-community trade of live animals and their products.

The List A of the Office of International Epizooties (OIE) including rapidly spreading diseases of major economic importance, such as highly pathogenic Avian influenza (AI) and Newcastle Disease (ND). The EU legislation to control Avian influenza is laid down in Council Directive 92/40/EEC (EEC, 1992a) introducing Community measures for the control of Avian influenza. For the Newcastle disease the Council Directive 92/66/EEC (EEC, 1992b) introducing Community measures for the control of Newcastle disease is laid down. In addition, the European Union adopted a Council Regulation 2160/2003/EC (EC, 2003b) on the control of salmonella and other specified food-borne zoonotic agents.

There are also a number of Council Directives covering the control of diseases such as:

- Directive 82/894/EEC on the notification of animal diseases within the Community (EEC, 1982).

- Directive 90/425/EEC concerning veterinary and zootechnical checks applicable to intra-Community trade in certain live animals and products with a view to the completion of the internal market (EEC, 1990a).

- Directive 90/667/EEC laying down the veterinary rules for disposal and processing of animal waste, for its placing on the market and for the prevention of pathogens in feedstuffs of animal or fish origin (EEC, 1990b) and amending Directive 90/425/EEC.

- Directive 90/539/EEC on animal health conditions governing intra-Community trade in, and imports from third countries of, poultry and hatching eggs (EEC1990c).

- Directive 91/496/EEC laying down the principles governing the organization of veterinary checks on animals entering the Community from third countries (EEC, 1991) and amending Directives 89/662/EEC, 90/425/EEC and 90/675/EEC.

The aim of this paper is to describe the regulations related to control of the above mentioned diseases and /or infections.

White-feathered broilers dominate world poultry meat production owing to their rapid growth and high feed efficiency. However, consumers' preference for colourfeathered and slow-growing meat-type quality chickens is growing in certain regions of the world. Among them, the ‘Three Yellow’ of China and ‘Label Rouge’ in France are two famous examples. The appearance (plumage, skin, combs and so on), meat flavour, and meat texture are the main attributes that attract customers to purchase them. For practical breeding, quality chickens were initially produced by direct use of native chicken breeds, which are generally slowly-growing with poor feed conversion. Currently, the breeding for quality chickens in China is characterized with crossbreeding between native breeds and highly-selected lines with rapid growth rate or relatively high egg production. The breeding objectives focus on improving growth rate and reproductive efficiency while maintaining original appearance characters of native chicken such as plumage colour, body shape, comb shape, skin and shank colour and so on. The performances of native chickens have been greatly improved by crossbreeding. Two-way or three-way crossing is commonly used in producing commercial quality chickens in China. In some cases, the dw gene has been introduced into maternal line for better reproduction efficiency and lower feed cost. For future development, breeders and producers will place more and more breeding significance on meat quality traits, which include meat flavour, tenderness, fat deposition, muscle fibre composition, visual characters and so on. As evaluation of these traits is expensive and time-consuming, new molecular markers will play more important roles. Once reliable markers are identified, early marker assisted selection can be performed with great selection accuracy and without slaughtering. Attempts to identify candidate genes related to meat flavour, muscle fibre, lipid metabolism and other physical characters have brought great potentials for future breeding of quality chickens.

The paper presents a global overview of the development of the poultry sector and of the role of small-scale, family-based poultry production in developing countries. Major initiatives undertaken to develop poultry as a tool for rural development and their rationale are presented. The constraints facing the future of small-scale poultry production are discussed, with a particular focus on poultry disease given the current outbreak of highly pathogenic avian influenza in Asia. Geographical ‘hotspots’ are identified where interventions are urgently required and where small-scale poultry has the potential to make a substantial impact. Finally, the paper stresses the need for more long-term and wider perspectives in the policies and strategies guiding the development of the poultry sector.

Molecular typing can help to manage and contain food-borne pathogen contamination in poultry and poultry products by providing a means to accurately evaluate sources and transmission routes of specific strains. Moreover, it provides an opportunity to identify the virulence determinant genes characterising the poultry strains that may cause human diseases.

This paper summarises the main applications of genotyping methods in the epidemiological investigations of Campylobacter and Salmonella, in order to identify clonally related and sporadic strains as well as to keep track of the geographical spread and prevalence shifts of epidemic and endemic clones.

Moreover, examples of applications of comparative genomics, by whole genome sequencing and microarray, are given in order to demonstrate how to investigate the difference in virulence determinant genes among Salmonella poultry strains and to distinguish different genotypes among Campylobacter strains. Although virulence determinants have been defined for Escherichia coli and Salmonella enterica, despite use of molecular typing and virulence assays for many years, virulence determinant genes have not been identified for Campylobacter. Putative virulence genes, such as cdt, have been discovered, but for the majority a clear role in disease causation has not been established. It is unlikely that comparative molecular typing using the methods available to a single laboratory will elucidate the virulence mechanisms and associated determinants. It is also, therefore, not yet possible to investigate differences in virulence gene complement for Campylobacter by genome sequencing and microarray in the same way as has been described for E. coli and S. enterica.

The Danida-financed Network for Smallholder Poultry Development (NESPOD) has several years of experience in supporting family poultry development at village level by focusing on women and the poor. By taking into account that women traditionally are taking care of poultry in most countries and that livestock of the poor mainly consist of small flocks of poultry, NESPOD has developed a strategy which involves not only disease control or introduction of improved breeds, but a holistic approach also taking into consideration social, cultural, marketing, credit and general management aspects. Tools involved in the development of family poultry range from sensitisation of village groups and organisation of women in poultry groups to training of village vaccinators, farmer field schools for poor illiterate women, organisation of local vendors, use of private veterinarians, and not least involvement of national research, education and extension institutions and international organisations. Results from Bangladesh, Benin, Senegal, Burkina Faso and Togo are very promising in terms of creating non-subsidised activities with clear benefits for poor farmers as well as local entrepreneurs.

Conventional methods of assessing bone integrity of layers have involved destructive testing on dissected samples. Bone ash, calcium and phosphorus levels give an indication of mineral content while breaking strength is at best a relative measure subject to numerous potential errors in methodology. More recently non-destructive methodologies have been accepted in human medicine, the most promising being quantitative ultrasonography (QUS) and axial x-ray micro-computed tomography (Micro CT). QUS relies on capturing sound waves that have travelled through the bone, where density will influence time between emitting and capture of the signal. In our preliminary studies, the humerus is the most appropriate bone for such studies since there is a minimum of overlying tissue. Micro CT relies on 720 images, taken at 0.5° angles around a sample, and then software allows rebuilding of a 3-D image. Micro CT also provides quantitation of density in selected areas on the image. Most Micro CT scanners currently necessitate isolated bone samples, although second generation machines will have the capacity to scan sedated animals such as chickens and small mammals.

Genetic selection is an important breeding tool that can be used for improving animal's coping capability to modern production environments or for increasing economic benefits. However, over the past five decades, commercial breeding programmes have primarily concentrated on traits directly related to productivity. As a result those breeding programmes ignore traits that may impact animal welfare. To address this issue, a selection programme termed “group selection” developed. This method takes into account competitive interactions by emphasizing performance of the group, rather than the individual. Results from the current studies have showed that chickens'productivity and well-being can be improved the same time. We further demonstrated an association between the selected survivability and productivity and its respective physiological characteristics. These findings indicate that group selection altered the chickens' physiological homeostasis which is reflected in the line's unique coping ability with intensified domestic environments. These changes in physiological homeostasis provide an opportunity gain new insights for the development of interventions aimed at ameliorating the adverse impacts of the intensified poultry industry.

It appears possible for free-flying native or feral wild birds to be responsible for direct or indirect spread of infectious agents from contaminated poultry product wastes to susceptible commercial poultry. Direct spread involves infected wild birds gaining access to commercial poultry. Indirect spread involves secondary spread to other free-flying birds that may subsequently gain access to commercial poultry.

In analysing the level of risk of such spread consideration is given to three elements. These are the susceptibility of wild birds to infection by the agents concerned, the opportunity for susceptible species coming into direct or indirect contact with both poultry product wastes and commercial poultry, and the occurrence of actual cases of such spread.

The scenario being considered is one in which poultry product wastes contain an infective dose of one of the agents of concern, namely avian influenza, Newcastle disease or infectious bursal disease. A review of the literature was undertaken to assist in assessing the likelihood of spread of these agents by wild birds.

Exposure of wild birds, to any of the three viruses of concern at product waste disposal sites, is a potential threat but the likelihood of spread to commercial poultry appears to be low. More obvious means of spread occur in the poultry industry, as biosecurity is often rudimentary. Spread of infectious agent by fomites, live poultry and infected wild birds could well be involved in transmission of disease agents between farms. Where live bird poultry markets or semi-feral village poultry exist they provide an obvious means of spread of these agents and involvement of access of wild birds to poultry product wastes is probably of little importance.

The likelihood of wild bird involvement in virus spread from poultry products could increase if a susceptible species with gregarious habits (flocking behaviour) leading to high population densities, were to frequent both poultry product waste disposal sites and commercial poultry premises. Some passerines are likely to frequent waste disposal facilities and poultry premises, but it appears that different species congregate at poultry premises than at waste disposal sites.

There is little evidence of spread of disease from waste poultry products to commercial poultry premises having occurred.

This paper presents a Technical Cooperation Project associated with the FAO Special Programme for Food Security (SPFS) in Chad. The project entitled “Diversification Component of the SPFS in Chad”, which started in November 2000 and ended in October 2002, focussed on improving the contribution of small ruminants (sheep and goats) and poultry (chickens, ducks and guinea fowl) to household food security. Only data from the poultry component are presented in this paper.

An initial analysis identified access to credit, goods and services, and markets as the main constraints faced by farmers wishing to expand their poultry production. High mortalities, especially in chickens, were identified as a major cause of low productivity. Through a consultative process that involved all the stakeholders, project interventions were designed to overcome these constraints. The project introduced credit with repayment in kind, access to animal health care, staff and farmer training, and demonstrated improved animal husbandry practices.

Sixty percent of the original 55 farmer production/demonstration units remain active and profitable. Guinea fowl and duck keeping proved to be the most profitable as their meat is in high demand during festivals, and guinea fowl lay during the wet season when there is a scarcity of eggs. Efforts to control Newcastle Disease were less successful and the disease occurred in 78 percent of the units keeping chickens. Credit repayments have started in 40 percent of the units. This pilot project has shown the potential of poultry as a means of increasing household income and it has become a model for SPFS programmes elsewhere in sub-Saharan Africa.

This paper reviews and presents data suggesting that the use of thyroxine (T4) to induce moult in poultry may be a viable alternative to previous methods involving feed withdrawal or feed avoidance. Studies completed in wild and domestic avian species have indicated that T4 is associated with the natural moulting process. Four experiments, spanning the range from using a purified, injectable form of T4 to a cost effective commercially available product, iodinated casein (economical source of T4) that can be fed to hens via a standard poultry ration, are presented. Since hens have full access to the diet during the induced moult, it is hoped that the procedure will be acceptable both to the poultry industry and to organizations concerned about the welfare of birds during this period of their annual cycle.

A review of QTL for production, behaviour and disease resistance traits published to the end of 2004 is presented. QTL were located randomly over the genome and there was little commonality between different studies for similar traits. However, there were several reports of QTL from different experiments in similar regions of chromosomes 1 (at 250 and 450 cM), 4 and 8 and for disease resistance on chromosome 5. Generally there were 6 to 8 QTL affecting the major production traits in experimental breed crosses and collectively they accounted for a substantial proportion of the line difference where this information was provided. The size of typical genome-wide significant effects for production traits was 0.3 to 1.0 phenotypic standard deviations. Genetic effects for growth traits were generally additive whereas about one-third of QTL for other production traits showed significant dominance effects. Variable reporting standards were noted and proposals for minimum published information are presented. Currently there are scientific opportunities for meta-analyses of results from experiments on body weight gain and considerable potential for combining data and results from different studies for other traits in the future.

Maximum daily temperatures in excess of 30°C are common in many table egg-producing regions of the world. Such temperatures require the application of specialized management and nutrition if laying hens are to produce eggs near their genetic potential. Environmentally-modified buildings have been shown to be especially advantageous for commercial layers that are housed in high density cage facilities. Directing air movement onto floor-housed birds has also been found to maximize heat loss and was beneficial as long as the air temperature did not exceed body temperature. This latter procedure was especially useful where sporadic incidences of heat stress were common.

Nutritional manipulation of the diet also offers advantages, especially in overcoming problems of reduced appetite. This principle has been shown to apply to both growing pullets and adult layers. Recent research has confirmed that optimum production during lay depends on the adult hen having an adequate gut capacity and sufficient nutrition during rearing. Egg production during moderate heat stress can be improved by increasing the intake of protein relative to energy but energy requirements will likely increase in severe heat stress. Dietary supplementation with ascorbic acid and vitamin E and a supply of cool drinking water have also been reported to improve production during lay but the response to the latter treatment varied with genotype.

The ovulatory cycle and moulting are associated with physiological and endocrinological mechanisms involving a complex interplay of light stimulus, hypothalamus, pituitary, gonads, thyroid and adrenal glands. During ovulation, the LH surge triggers the release of a mature follicle. With advance in the age of a laying hen, egg production decreases coinciding with decrease in ovarian steroids and gonadotropins. Moulting occurs when oestrogen, progesterone and luteinizing hormone are low while thyroid hormones and corticosterone are high. The physiological processes observed during induced moulting are common to those found in natural moulting. Moulting results in the rejuvenation of reproductive tissues of old laying hens, preparing them for another laying cycle. Vitellogenin provides the two proteins (lipovitellin and phosvitin) to the developing yolk, at the same time serving as their transport protein through the blood stream. Low levels of vitellogenin in the plasma of moulting hens are attributable to decrease in oestrogen during moulting since production of vitellogenin from the liver is stimulated by oestrogen.

Village poultry play a vital role in many poor rural households. They provide scarce animal protein (in the form of meat and eggs) and can be sold/bartered to meet essential family needs such as medicine, clothes and school fees. They also provide manure and pest control as well as being used in traditional ceremonies. Village poultry are generally owned and managed by women and children and improving their production can provide the first step out of poverty for the rural poor.

The Australian Centre for International Agricultural Research (ACIAR) has supported village poultry research in many countries since 1984. This research has had some significant outcomes including: the control of Newcastle disease (ND) using Australian derived live thermotolerant vaccines in a variety of poultry production systems in several countries; description and quantification of the scavenging feed resource base of low input/low output systems; development of gender-sensitive extension materials and methodologies suitable for use in remote rural areas in Asia and Africa; and the development and registration of a new duck plague vaccine in Vietnam.

The thermotolerant ND I-2 vaccine remains viable for periods away from the cold chain, can be administered by various routes and induces an acceptable level of protection under village conditions. The vaccine master seed, together with the ND Laboratory Manual, is made available without cost by ACIAR.

In developing countries where ND is endemic, outbreaks regularly result in high mortalities and in countries where it is not endemic, sporadic outbreaks make vaccination advisable. The implementation of an effective ND control programme in countries in Africa and Asia has resulted in increased chicken numbers, increased household purchasing power, increased home consumption of chicken products and increased decision-making power for women.

However, sustainable programmes for the control of ND in village chickens have been difficult to achieve, often due to limited appreciation by official agencies of the benefits of village poultry. Experience has shown that a sustainable ND control programme is composed of five essential components: a) an appropriate vaccine and vaccine technology; b) effective extension materials and methodologies that target veterinary and extension staff, community vaccinators and farmers; c) simple evaluation and monitoring systems; d) economic sustainability based on the commercialisation of the vaccine and vaccination services and the marketing of surplus chickens and eggs; and e) support and coordination by relevant government agencies for the promotion of vaccination programmes.

Details of ND control in village poultry are provided on the ACIAR website, www.aciar.gov.au and by the Australian Agency for International Development www.ausaid.gov.au.

The present review focuses on three avian DNA viruses and two retroviruses; the DNA viruses are Marek's disease, chicken anaemia and fowlpox virus. The two avian retroviruses, reticuloendotheliosis and avian leucosis virus subgroup J were detected in theirproviral DNA form in the feathertip extracts, thus resembling DNA viruses. Whereas most previous reports focused on experimentally-infected chickens, in the present study we analysed naturally-infected commercial flocks.

We review now the presence of various viruses in the chicken feathers, showing the efficacy of feathers for research and diagnosis alongside with other organs. Data on the relative ability to detect viruses on feathers over prolonged periods of time is also provided. We also analysed the efficacy of feather testing for the assessment of environmental infection in poultry houses. The data obtained by the differential diagnosis of various viruses in conjunction with the analysis of organs from the same chickens, showed that the feathers were very effective for diagnosis and deserve more attention.

The modern poultry industry has a remarkable record in reducing mortality, applying a combination of effective disease control, adequate nutrition, good husbandry and genetic selection. Primary breeders, specialized in the adaptation of layers, broilers and turkeys to changing demands of a global food market, have made three major contributions in the past: (1) eradication of vertically transmitted disease agents such as lymphoid leucosis viruses, mycoplasmas and salmonellae; (2) selection between and within lines for general liveability and specific disease resistance; and (3) dissemination of management recommendations which may help customers to minimize losses at the commercial level. Current focus is on components of liveability which are directly or indirectly linked to poultry welfare: selection against feather pecking and cannibalism in egg-type chickens and selection against leg disorders and heart/lung dysfunction in rapidly growing meat poultry.

European duck meat production is based on the use of Pekin, Muscovy and Mule duck genotypes that vary in their behavioural and physiological characteristics. Furthermore, large differences exist in their housing and management conditions. The aim of this review is to discuss the welfare of these different genotypes in typical husbandry systems, focusing on ducks kept for meat production. Firstly, factors that can affect duck welfare, such as stocking density and group size, access to straw, an outdoor run, or open water, are described. Secondly, welfare problems such as feather pecking, fear and stress, and health problems are assessed. Thirdly, the various systems used in Europe are described for these aspects. Giving ducks access to straw, an outdoor run, or open water increases the behavioural opportunities of the ducks (foraging, preening, bathing, and swimming), but can also lead to poor hygiene and increased health- and food safety risks. Therefore, practical solutions that allow expression of natural behaviour, but do not lead to hygiene or health problems have to be found and some practical suggestions are provided.

Recent decades have seen significant progress in the genetic selection of fast-growing meat-type broiler chickens. However, fast growth has coincided with inferior development of the visceral systems, especially the cardiovascular organs, contributing to difficulties in coping with heat stress. Global mean surface temperatures are expected to rise during the coming years and climate control systems are expensive. This situation, where growth rate and heat production increases on a yearly basis and the future foresees increasing temperatures, demands an efficient means to economically improve the acquisition of thermotolerance by broiler chickens in hot climates. In homeotherms, three direct responses participate in thermotolerance acquisition: rapid thermal shock response, acclimation and epigenetic adaptation. Together with physiological understanding, it is important to understand the physical aspects of broilerexcess heat dissipation. This paperfocuses on airvelocity as a principal parameterwhich dramatically affects sensible heat loss and its contribution to the ability of acclimated or epigenetic adapted broilers to efficiently maintain a favourable energy balance underhot conditions. Heat transfer equations and models for different body parts are presented which were used to determine energy balance components at different air speeds based on thermal imaging. The studies reviewed demonstrate that: (a). air velocity plays a major role in energy balance at high ambient temperatures; (b). the optimal air velocity for achieving maximal growth performance differs at different ambient temperature and has a point of inflection at ambient temperature below 30°C, where chilling affects the broiler;(c). high air velocity at high ambient temperatures affects the ability of broilers to maintain total body water, most probably as a result of cutaneous waterloss; (d). thermal conditioning at an early age increases the capacity of broilers to efficiently lose heat by radiation and convection; (e). genetic selection for growth performance has been to some extent at the expense of the broiler's ability to maintain favourable energy and water balances.

This paper describes, under laboratory and/or field conditions, an approach that could be used to predict nitrogen (N) mineralization of poultry litter. Proper composting of poultry litter results in N mineralization, reducing or eliminating the environmentally harmful effects of ammonia (NH3) odours and nitrate leaching. Addition of straw to poultry manure provides sufficient available carbon and increases NH3 binding capacity, overruling any greater influence of diet composition on methane (CH3) formation. C:N ratio ranges (6–25) vary in the amount of low N loss depending on substrates. Aerobic decomposition of manure results in formation of humified organic compounds and decreased nutrient availability, while anaerobic decomposition forms low molecular weight compounds (volatile fatty acids and NH3+- N). The differences in the size of the composted particles results in physical separation and decomposability of high and low C:N ratio substrates. Temperatures ranging from 14 to 35°C did not affect the rate of N mineralization, but affected N loss from poultry manure pellets by decay nitrification at 14 and 35°C compared with 25°C. Uric acid and undigested proteins in poultry litter have optimal degradation rates at pH of 5.5 or higher, with the optimum pH for uricase being about 9. Variations in manure composition are seen between different species such as cattle, swine and poultry. The chemical composition of the manure and not the substrate N status influences the rate of decomposition or microbial availability. The N mineralization potential of some vegetable residues correlated better with the total and water soluble N contents than with their C:N ratios. Poultry manures are applied to agricultural soils at rates determined by the amount of available N that they are assumed to contribute to the crops. Many equations have been developed to calculate these application rates.

Despite efforts to develop intensive poultry production, family poultry (FP) are still very important in developing countries. In most developing countries, the keeping of poultry by local communities has been practised formany generations. FP keeping is a widely practised activity. More than 90% of rural families in most developing countries keep one ormore poultry species (i.e. chickens, ducks, guinea fowls, geese, pigeons, etc.), and all ethnic groups tend to be involved in FP production. Although generally requiring low levels of inputs, FP is an appropriate system for supplying the fast-growing human population with high-quality protein, while providing additional income to the generally resource-poor small farmers, especially women. FP is also a source of employment for underprivileged groups and less-favoured areas in developing countries. However, constraints facing FP production systems are related to high mortality (mainly due to Newcastle disease), housing, feeding, breeding, marketing, credit, education/training, extension and information dissemination. Organizers of FP development programmes must be sufficiently sensitive to socio-cultural and economic circumstances of potential beneficiaries. Developing schemes that aim to promote and improve the FP sub-sectorin a way that is sustainable must not underestimate the specific roles and contributions of relevant members of local communities, as well as their different gender groups i.e. women, men, boys, girls, young and old persons. Therefore, getting new information and other various interventions to the front line of production requires well-designed gender research. This work, which must be done by multi- and trans-disciplinary teams to ensure that the production environment in which FP-keeping farmers work is fully understood, helps to identify the target groups of FP producers for development programmes such as in training, extension, information dissemination, provision of inputs and credit, marketing of poultry and their products. Ways to improve the productivity of FP management systems by taking into account socio-cultural, especially gender, aspects in the design, implementation, monitoring and evaluation stages of FP development programmes at community level are also explored.