First of all, welcome to the first issue of 2014 and, if belatedly, happy new year to all our members and readers. In this issue we have a lot of association news, which is indicative of the great activity of the branches and WPSA associations around the world, which is a major indication of the continued importance of poultry science globally.

In this issue we have various papers, covering aspects of genetics, immunity, welfare, nutrition and diseases. The spread of topics is encouraging, as, from an editorial point of view, we try to make the journal as varied as possible to appear to all readers, although sometime this is not always possible as we are highly dependent on the types of papers that have been submitted and processed in time for publication.

I would like to take this opportunity to express my thanks to all those who help us produce the journal on a voluntary basis – especially the reviewers. We are always looking for new reviewers, to assuage the burden on our regular ones. However, anyone who reviews for the journal has our heartfelt thanks. In my discussion with other editors, we always talk about finding and keeping good reviewers for a range of topics, as these really are the main drivers for getting papers published, especially in areas where I have limited scientific knowledge!

We have a special mention this issue for Dr Gordon Rosen, who has been a tireless supporter of the WPSA for many years and initiated donations for supporting membership. Gordon is not only a colleague but also a good friend and mentor to many in the poultry science world – and we thank him for his generosity.

Finally, there are a range of poultry events in 2014 that are appropriate for a range of scientific disciplines. Check out the websites directly from the news and events section – or check out the WPSA website for the links to the information, I shall be attending certain meetings throughout the year on the hunt for new and novel review papers – and I hope to see you there.

Dr Lucy Waldron

Editor

Poultry meat consumption in Kuwait has increased rapidly over the past 15 years. The objective of this report is to examine and explain the development of the Kuwait poultry during this period with a special focus on the reasons for the recent rapid expansion of the broiler breeder industry.

In 2011, 39,396 tonnes of poultry meat were produced in Kuwait with a value of $56.1 million, but this accounted for only 20% of the total poultry meat consumption (97.5 kg/person). The Kuwait poultry industry is economically competitive with imported poultry meat, but expansion is limited because of the availability of suitable land and water resources. Poultry companies therefore increase revenue by producing a higher proportion of higher value products (fresh/chilled meat, further processed chicken products and live bird sales). The industry now provides almost all its requirements for broiler chicken hatching eggs, but production efficiency is reduced in the late summer months when combinations of high temperatures and humidity give extreme climatic conditions. There is a need for research to improve production efficiency and training and education of staff to ensure a continued skill base for the industry.

The principal salmonella serovar associated with infections linked to eggs and egg products in the UK, most European countries and North America is Salmonella enteritidis. However, other serovars have also been implicated in a number of egg-associated outbreaks, most notably S. typhimurium exhibiting a range of phage types. The present article reviews human egg-associated salmonellosis associated with non-S. enteritidis serovars, predominantly in the European Union (EU) but also world-wide, using information from published literature and epidemiological databases. There are also brief reviews of S. enteritidis and of mechanisms leading to egg contamination by salmonella. The numbers of egg-associated infections caused by non-S. enteritidis serovars are fairly substantial (for example 22% of outbreaks and 11.5% of more than 20,000 cases in the EU in 2008), and such infections have resulted in hospitalisations and deaths. Furthermore, in parts of the world where S. enteritidis historically has not penetrated laying hen breeding flocks, egg-related salmonellosis is a problem associated specifically with non-S. enteritidis serovars. Control measures to limit the incidence of S. enteritidis and S. typhimurium in poultry flocks are vital. It is therefore important that close surveillance of salmonellosis incidence and serovars in laying flocks is used to establish suitable biosecurity and vaccination programmes throughout EU Member States and elsewhere.

This review brings together and consolidates the large amount of research on acute phase proteins (APPs) that has been undertaken in chickens. Acute phase proteins are secreted from the liver as a result of inflammation or infection that can be measured in plasma. They have been well-characterised in other farm animal species and have been measured in a wide variety of poultry research areas. The acceleration in chicken APP research is in response to increased interest in ways the immune responses of the chicken can be measured and compared during infection or environmental or nutritional changes. All APPs that have been identified and characterised in chickens are described in the following review and their responses during infection discussed. The APPs are tabulated with basal values and classification to provide a comparative and useful reference. The ways APPs can be measured in chickens and the assays available are also described. This review will detail the functions of the positive APPs in chickens and their behaviour during an APR.

Chickens (Gallus gallus) were the first avian species selected for whole genome sequencing because of their economic value, use as a food source, livelihood security and research importance. Any living organism contains a galaxy of genes which express all the phenotypes or characters by encoding proteins and peptides, and playing regulatory roles in the biological system. Functional genomics in turn, is a multidisciplinary approach to identify and demonstrate the functional roles of genes and other regulatory molecules such as microRNA and CpG methylation in biological pathways. In the last two decades, the chicken genome database has made significant advancements in accruing large amounts of genomic information through employing advanced bio-informatic tools. Several techniques such as cDNA microarray, serial analysis of gene expression, massively parallel signature sequencing, cDNA subtractive hybridisation and next generation sequencing have been utilised to investigate the genome-wide expression profile instead of revealing expression pattern of one or a few genes in various avian species. Expressed sequence tag or cDNA sequences are the key factors for identification of novel genes and understanding the complex molecular cascades of ontology. A large-scale cDNA library has been constructed from embryonic and adult tissues and consequently identified the presence of about 19,000 functional genes in chickens. The micro RNAs play crucial role in gene expression and to date, approximately 496 micro RNAs have been characterised. The non-coding RNA alters gene expression involved in cellular process, by modulating the chromatin architecture, transcription, RNA splicing, editing, translation and turnover. Functional genomics studies have been extensively used to identify genes associated with several production traits, immuno-genetic mechanism, host-pathogen interaction, pathogen biology etc. Nutrigenomics have determined the genomic mechanism involved in feed utilisation, metabolism and cholesterol synthesis etc., which ultimately reveal potential applications for improving the nutritional efficiency of birds. This review discusses the tools and utility of functional genomics approaches in chicken.

The changes in the immune function of birds obtained during decades of intensive selection are rather disadvantageous. Today's chickens and turkeys are more susceptible to different infectious and metabolic diseases and exhibit a high mortality rate. Subsequently in recent years there is growing interest in the use of feed additives with immunomodulatory properties in intensive poultry production. This article reviews and discusses the results of current studies on the effects of yeast cell products on the different mechanisms of the immune system in poultry. The majority of the experiments presented in this review indicate that the use of yeast derivatives may have a beneficial influence on the immune system and resistance to the colonisation of pathogenic microorganisms. However, the positive effect of yeast derivatives on the immune system is not always reflected in an improvement in production parameters, especially when the experiments are conducted on healthy (non-challenged) birds.

Pheasants and peafowl have been used as ornamental birds worldwide because of their beauty and use as game birds. They can be hampered by the disease mycoplasmosis in breeding pens, wildlife parks and zoos. This review paper describes the prevalence, diagnostic procedures and different combinations of treatments for mycoplasmosis in these birds. This paper also discusses the association of prevalence with management practices.

There has been growing interest in the development of natural methods of coccidiosis prophylaxis. Vaccination against coccidiosis with live oocysts is regarded as effective in the control of avian coccidiosis, but in some conditions, such as poor sanitary management or incorrect application of the vaccine, may lead to poorer performance, measured as reduced weight gain and feed efficiency, in comparison with prophylactically medicated birds. Such reports are the reason for widespread reluctance to use anticoccidial vaccine in broilers. This paper reviews broiler studies in which nutritional methods as performance and/or immune-supporting factor with regard to anticoccidial vaccination were investigated. The results of some of the studies presented in the article indicate that feed additives with immunostimulating properties, along with proper protein levels in the diet, may have a beneficial effect in cocci-vaccinated broilers.

Laying hen rearing systems have been the focus of scientific research for many years. Over the last few decades, new laying hen rearing systems have been rapidly introduced in an effort to harmonise poultry health and welfare with consumer, producer, industry and environmental demands. Given the above situation, the subject matter of this paper was a comparative review of the results obtained by different authors on the effect of rearing system on productive traits (egg production and mortality) and egg quality characteristics (egg weight, proportions of main egg parts, Haugh units, yolk colour and carotenoids) in laying hens. Although productive performance in alternative systems is often lower compared to conventional, intensive layers, eggs from alternative systems have been proven in numerous studies to have better nutritional properties. Moreover, research results indicate differences within rearing systems. In view of this, this overview of the literature on the use of different rearing systems in table egg production can serve as a tool in determining the future direction of research as well as an indicator of its practical application.

The aim of this review was to analyse the available literature on the effects of the use of microelements and their chelated forms on performance parameters of poultry as well as the cholesterol content in the tissues of broiler chickens. Published research has indicated that the significantly lower levels of organic minerals had a positive influence on the production performance of meat poultry and improved the production performance of laying hens and their heavy line hybrid parents. This has major impacts not only in terms of more efficient utilisation of chelated minerals in poultry diets, but also for less excretion of unused inorganic minerals into the environment, which is a major problem in many countries.

Poultry red mite (Dermanyssus gallinae), the haematophagous pest of egg laying hens, is an important problem in poultry production in many parts of the world. Control has typically relied on synthetic acaricides in spite of advancements in immunological, biotechnological and genetic approaches. However, the repeated long term use of these compounds has resulted in the development of drug resistant populations of poultry mites, therefore, the availability of effective acaricides is diminishing rapidly. Due to this, there is need for the continuous availability of new chemical acaricides to replace the older types, however the development and registration of new acaricides is a long expensive process, therefore, preserving and maintaining the effectiveness of available acaricides is essential.

This review has two parts; the first is to provide the basic understanding of acaricide resistance in D. gallinae while the second part provides more detailed knowledge about the management of resistance to preserve the efficacy of available acaricides.

Deep pectoral myopathy (DPM) of musculus pectoralis minor is an anomaly observed in gallinaceous poultry. To date its cases have been reported in adult pedigree turkeys and hens and in recent years also in broiler chickens. This degeneration is manifested in an abnormal appearance of breast muscles, with changes in colour from pink to green, as well as changes in the texture of the muscle tissue. The anomaly is found most frequently in genetic lines of chickens characterised by dynamic weight increment in the rearing period as well as a considerable increase in the proportion of pectoral muscles. The mechanism for the development of myopathy is already well known. It is related with ischemic necrosis initiated by rapid physical activity of birds, which mobilises pectoral muscles, normally relatively inactive in modern intensive animal management systems. Absence of symptoms manifested in vivo results in a situation when muscles affected by myopathy are identified only during carcass dissection. An increasing number of cases of this anomaly, as well as the fact that necrotic lesions affect valuable carcass elements make this problem one of great importance for chicken growers and abattoirs and poultry processing plants. In recent years DPM cases have been reported with increasing frequency in the USA, Italy, Greece and Bulgaria in commercial genetic lines. In Poland, a number of DPM cases have been recorded in large populations in flocks of five to seven week old chickens from 0.02% up to 1.9%. Risk factors for the occurrence of DPM on farms have been analysed, and are considered mainly due to intensive wing flapping. Identification of these factors may result in better farm management and constitute the basis for the DPM prevention system. A solution to this problem is not available currently.

To ensure health and reproductive performance, broiler breeders are feed restricted during the rearing period and, to a lesser extent, during the production period. Although restricted feeding improves health and bird welfare, on the other hand the birds are chronically hungry and suffer from frustration of feeding motivation, which has a negative effect on bird welfare. The aim of the current paper is to give an overview of the role of feed (nutritional aspects as well as feeding management) as a possible tool to improve broiler breeder welfare. Possible strategies discussed are 1) dietary dilution, by reducing the energy content and/or increasing the NSP content, by adding soluble or insoluble fibres to the diet; 2) adding appetite suppressants (e.g. calcium propionate) to the diet; 3) changing feeding management (e.g., scattering feed in the litter). Some of these strategies, i.e. dietary dilution or adding appetite suppressants, positively affect behavioural patterns of the birds, by reducing stereotypic pecking and eating motivation, and increasing the time spent sitting. Appetite suppressants have however been criticised for causing birds to feel ill. These behavioural changes, however, can only be considered as indirect parameters of improved bird welfare and there is still a need for a reliable indicator of hunger. It is clear that nutritional strategies can be helpful in reducing hunger stress in broiler breeders. Nutrition, however, cannot fully solve the broiler breeder paradox. The main reason for this paradox is related to breeding goals that are focussed on improving feed conversion and increasing breast meat percentage. Future genetic selection should aim at uncoupling the link between (re)production and welfare or reducing the conflict between these outcomes.

Alternative laying hen rearing systems have been rapidly introduced into poultry production in an effort to harmonise poultry health and welfare with consumer, producer, industry and environmental demands. They are an integral part of modern egg production. Husbandry systems for keeping laying hens have an impact on, inter alia, the chemical composition of eggs. The subject matter of this study is a comparative review of the results obtained by different authors on the effect of rearing system on chemical composition (proteins, lipids, cholesterol, vitamins and fatty acids content) and hygienic conditions of eggs from different rearing systems of laying hens. Eggs from these laying hen rearing systems have been proven by a large body of literature data to have better nutritional properties. Moreover, the results analysed also indicate differences within rearing systems. Rearing systems also have an influence on hygienic and microbiological quality of eggs. In view of the above, this comparable overview of the literature on the use of different rearing systems in table egg production can serve as a tool in determining the future direction of research as well as an indicator of its practical application.

Major marker genes are believed to confer not only adaptability to the tropical climate, but also resistance to diseases. During the last two decades, many investigations have observed that naked neck and frizzle genes have favourable effects on immunocompetence in chickens raised under high ambient temperatures. As a result, several tropical countries have introduced these genes in breeding programs to improve both the productive performance and survival rate of chickens.

The indigenous chicken (Gallus gallus domesticus) genetic resources (IC) comprise more than 80% of the overall poultry population in rural villages despite their low productivity. However, a holistic approach that increases productivity without increasing production costs or leading to loss of biodiversity is presently limited. Conversely, in most developing countries, there is almost no organizational structure for breeding programmes for improving and conserving IC. These locally adapted IC can only be conserved in the most rational and sustainable way by ensuring that they are functional part of different production systems. Their conservation should be through utilisation if they are to be of any benefit to the poor rural households. This discussion focuses on five very relevant questions that need to be answered if the conservation of IC is to be effective and sustainable: What, why and how should we conserve, who are the stakeholders and what are their roles in conservation efforts?

The World’s Poultry Science Journal is indebted to Prof J.A. Castello, Prof D.K. Flock, Dr D. Grastilleur, Dr S. Cherepanov and Prof N. Yang for the translations of these summaries.