Well the conference season is once again upon us, and, at the time of writing, I have already attended two conferences for WPSA, and will also be at the Turkish meeting towards the end of the year, with fellow board members. It’s interesting to see how fast things can sometimes change within an organisation. The latest statistics show that we have several new branches, notably in developing countries, whilst in some more established regions we are actually seeing a decline in membership. As members are the lifeblood of any organisation, it’s essential to promote the WPSA and create an environment of enthusiasm for the future of poultry science. Indeed, we have much to celebrate, for plans to commemorate the 100th Anniversary of the WPSA for 2012 are already in the pipeline. Certainly the Journal will be hosting special inclusions to mark the centenary, so watch this space! However there are also many other technological aspects to the WPSJ now available for members – making it easier and more efficient for you to get hold of the information and papers we have on offer. Have a look at the information in this issue to see how you can get the most out of the Journal. For any of you who are not already registered, online subscription is a fast, convenient way to access information and papers. We are now also working towards access to the WPSJ via mobile phones – which is a great way for members in developing countries, where the postal system or computer access may be unreliable. As the world of science gets faster and broader, we all need a reliable, quick way to access papers and literature information, so please do take advantage of these technological tools to ensure you’re not missing out on any information relevant to your specific field of work.

The Journal continues to grow in terms of quality, standing amongst peer publications and general popularity – which is a great result for all involved. At the end of June we will have our next citation rating (impact factor), which has consistently improved over the last few years, and we hope it continues to do so. Please keep those papers coming in. I’m always looking for extra variety in topics covered, and don’t be afraid to send in a review that’s maybe not mainstream – we are always open to new areas of poultry science.

So, please take a few minutes to go online and have a look at how you can get best use from the information we have in the Journal and on the WPSA website.

Dr Lucy Waldron

Editor

As I sit and write this, it’s a beautiful autumn day in England, and the harvest is well underway. At home in New Zealand, we are just starting to see signs of spring, after a long cold winter. Wherever you are in the world, there is always something agricultural to see and note that as always, the cycle of crop and animal production continues. However there are some interesting effects of the economic woes many countries have gone through recently (and many still are). Not least, for someone like me who travels around as part of my work, is the foreign exchange rate differences. Certainly the Euro and the Pound are both very weak against the NZ dollar – with the usual benefits and problems that entails. It will be interesting to see how international trade copes with this. Living in a country vastly dependent on agricultural exporting markets, I have certainly had many discussions with colleagues about how the strength of our currency could impact overseas sales of meat, milk and eggs. We shall wait and see.

As for the WPSJ, we continue to receive ever more varied papers – as you will see from this latest issue, with topics ranging from branding and economics, to mineral nutrition and GM feed materials. Our ratings this year have held well against the 1.6 high in 2010, which is very gratifying. However we are increasingly struggling, as are other journals, to find reviewers. This adds substantial amounts of time in processing a paper, so if any members out there are willing to help review papers in their area of expertise, do let us know in the Editorial Office.

Although many of you will receive this well after the event, I would like to take this opportunity to congratulate Professor Ravi Ravindran of Massey University on his recent award from PSA – the first non-American to receive such an honour. Ravi is a much respected poultry scientist who is highly active in his own research as well as post-graduate supervision, so this is very well deserved. I trust you enjoy this final issue of 2011 – we are already hard at work on the 2012 issues, including organising centennial papers from the individual working groups, looking at how each discipline in poultry science has changed over the lifetime of the WPSJ. Additionally we have the 2012 Wold Poultry Congress in Brazil to look forward to – and trust that will generate a lot of potential review papers in novel and emerging areas.

Dr Lucy Waldron

Editor

Well winter is certainly with us in New Zealand with rain and wind, but it seems that other parts of the world aren’t having the summer they were expecting. As a nutritionist, feed materials are a main interest of mine, and yet again it seems that harvests are likely to be poor this year, making it difficult to farm in an economic fashion. The conference season is well under way at the time of writing, and although most people are gearing up for the WPC next year in Brazil, there are still some interesting events regarding poultry. The Board is holding its meeting at the Turkey conference at the end of October/start November and I would like to thank the organisers there for hosting us. It should be an enjoyable place to work for a few days.

In this issue you will see that we have a variety of papers, and it’s very encouraging that more authors from different scientific spheres are using the WPSJ to publish their reviews. We are getting more INFPD papers coming in as well – which is important as encouraging poultry production in developing countries is a key tenet of the Association. Of course, it’s impossible to control what gets submitted from my point of view – but variety in topics is so good for our readership that I would like to encourage anyone who is ‘doing something different’ to consider putting in a review online. On that topic – we still have some problems with authors not taking on board the fact that we only publish review papers not single experiments. The instructions for our content and formatting are very clear – so please read them is you are an author. Please do not submit single experiment s to me as this costs us money that we have to charge to the authors.

In June I will get the latest ratings for the journal – the quality standard all journals are subjected to on an annual basis which gives an indication of how important we are in the field of agricultural science. Current we are at tenth place in our category which is excellent for a small journal that is only published quarterly. So keep the papers coming and I hope you all find something of interest in this issue.

Dr Lucy Waldron

Editor

First of all a Happy New year to everyone – as I am writing this on 23rd December and the new year seems a way off yet. However I do hope everyone had a very good seasonal break, wherever you are and whatever denomination. 2010 was a busy year at the WPSJ editorial office, with many new systems coming on line along with their accompanying issues. We have now cleared the backlog of papers that were sent in via the old, direct email system, and many thanks go to Dr Shay Hill in my New Zealand office in this endeavour – and the many hours she spent making sure the old papers were finalised. So we now are completely operational regarding submitting papers online, even though many authors still try to submit the old way and have to be redirected, I’m sure we’ll all get used to it. Happily, submitting to the WPSJ is still a free service – unlike most journals nowadays. At the Editors office, we are very mindful of trying to encourage papers from other, less well represented areas, to keep a broad level of interest for our readers. We have also been discussing how best to incorporate more commercial work, to provide more relevant information for our commercial members, although the best vehicle for this has yet to be determined. I also managed to confuse a great many people by changing my name back to my maiden name – but everyone seems to be getting used to that too!

Many thanks to all who submitted papers in 2010 via the new system. We did have some glitches, as expected whenever one undertakes such a project, but we worked through them and hopefully the submission system works fine now. Our partners in setting this up were Cambridge University Press, and their help has been invaluable in this exercise.

As for 2011, it will be interesting to see how things work out for the poultry industry. Major issues still involve the poor harvests and associated feed costs that go hand in hand with such situations. Increasing media focus on how meat and eggs are produced and the role of supermarkets may also change some of the paradigms regarding production and ethics, However, as the various global economies are still facing problems, it’s hard to see how such considerations can be balanced against the need for a source of safe, cheap food by the general population.

So, it remains for me to say that I am very much looking forward to seeing you all at various meetings this year and receiving your review papers as well.

Dr Lucy Waldron

Editor

Understanding the metabolism of lipoproteins in birds is important to enable nutritionists to design diets aimed at obtaining better meat characteristics and egg quality, and can furnish useful information for future studies. In comparison to mammals, there are a number of expressive differences in the metabolism of lipids in birds, such as the transport of dietary lipids to the liver, hepatic lipogenesis and the presence of unique lipoproteins in the blood (portomicrons). Greater differences are found in egg-laying hens during the production phase, in which lipoproteins produced in the liver, under the action of oestrogen, are used for the formation of the egg yolk. The regulation of the lipid metabolism by hormones and the participation of key enzymes associated to advances in molecular biology techniques could assist in the genetic selection of more productive birds and better quality products for consumers.

The gizzard has a number of important functions, such as aiding digestion by particle size reduction, chemical degradation of nutrients and regulation of feed flow, and responds rapidly to changes in the coarseness of the diet. This review summarises findings on the function of the gizzard, the interaction between diet and gizzard function, and the nutritional consequences of these interactions. Due to the reported improvements in nutrient availability when structural components which stimulate gizzard development has been added to the diet, it may be recommended to include at least 20 to 30% cereal particles larger than 1 mm in size, or to include at least 3% coarse fibres such as oat hulls, in the diet.

Calcium is the most prevalent mineral in the body and is important for many physiological processes. However, the amount of calcium in modern diets has both economic and nutritional consequences for producers. Dietary calcium has been shown to reduce the efficacy of both endogenous and exogenous phytases resulting in decreased phytate-phosphorus availability, increased phosphorus excretion as well as facilitating the formation of mineral-phytate complexes. Reducing the concentration of dietary calcium has been reported to improve phytase efficacy and phytate-phosphorus availability, however, this is often at the expense of optimal skeletal integrity. Choice feeding employs the principle that poultry have the ability to select a nutritionally balanced diet from multiple sources and previous studies have shown that poultry have a calcium specific appetite. However, the evaluation of choice feeding systems for broilers has predominantly focussed on the effects of providing separate sources of protein and energy concentrates. Though literature is available for laying hens, scant information is available pertaining to choice feeding of a separate calcium source for broilers. This paper reviews the available information on choice feeding systems in poultry with focus on the application of this in broiler production systems.

In 2008 as in previous four years, campylobacteriosis was the most frequently reported zoonotic disease in humans in the European Union (EU) with fresh poultry meat as one of the most important reservoir of human infection (EFSA, 2010a). The reduction of campylobacter prevalence and load in live poultry is believed to be one of the most effective ways of reducing the contamination of foodstuffs and the number of human campylobacter cases. On this purpose some European Member States adopted national campylobacter control or monitoring programs but a European strategy to reduce campylobacter is still missing. The first step in this direction has been a European Union-wide baseline survey carried out in 2008 at slaughterhouses to obtain comparable values of prevalence of campylobacter in broiler batches and on broiler carcasses for all Member States. Current pre-harvest strategies available to reduce campylobacter contamination in poultry production include the application of on-farm biosecurity measures, the decontamination of litter, and the supplementation of feed with compounds inhibiting campylobacter and the treatment of drinking water. Moreover, novel strategies, specifically targeting campylobacter control at pre-harvest level, are in progress, including administration of probiotics, vaccination, antibiotics used in combination with molecule able to prevent the emergence of antibiotic resistance and antimicrobial alternatives (i.e. bacteriophages, bacteriocins). This paper is an overview on pre-harvest control strategies.

There is a wide array of factors, of which feed formulation is one, that can drastically affect both the quality of the feed produced as well as the parameters associated with the production of the feed in the mill. It has long been the practice in commercial broiler production to pellet the feed. It has been accepted at this point that feeding a diet with high quality pellets leads to better performance compared to the same diet with low quality pellets or in mash form. On the other hand, producing a high quality pellet is not the typical result in a large feed mill. In large mills, great quantities of feed must be produced in a short time frame and this is usually accomplished by running the mill at a high production rate and pelleting the diet through a relatively thin die. This usually results in decreased conditioning time and contact with the die for the diet, and consequently a lower quality pellet results, mainly because these are the two primary locations for the physiochemical reactions such as starch gelatinisation and protein denaturation that cause pellet binding. In this review we will discuss research pertaining to the use of different grains, by-products, minerals, pellet binders and most notably feedstuff constituents and their effects on both physical pellet quality as well as feed manufacturing variables such as energy usage and production rate when the data is available. The main focus will be given to research performed within the last decade. However, we have placed no restrictions on the research referenced based on publication date as there is always quality research with pertinent findings that have stood the test of time.

Poultry production has been identified as a major producer of NH3 and, to a lesser extent, of greenhouse gases (GHGs) mainly by national emissions inventories. However, since most national inventories are based on average emission factors for each type of animal (‘tier 1’ approach), the factors that influence these emissions (through breeding and manure-management practices) are not taken into account. The first step to improve inventories and propose mitigation options (e.g. best management practices, innovative systems) is a better understanding of the drivers of gaseous emissions and the identification of key factors for the mitigation of NH3 and GHG emissions. This paper presents a literature review of NH3 and GHG emissions from poultry housing, with a focus on the influence of practices and rearing conditions. It appears that flock-management practices (e.g. dietary practices, slaughtering age) and manure management (e.g. manure removal frequency, chemical treatment of litter) are presented as efficient ways to reduce emissions. Environmental conditions (e.g. ventilation rates, temperature) influence emissions; however, it was not possible to assess the effects of different combinations of these factors (compensatory or synergistic). Some factors, such as stocking density, which may play a significant role, were not studied. Modelling approaches that integrate these key factors with climate factors can be used to update emission factors in emissions inventories, consider national variability and uncertainties in mitigation scenarios, test synergistic and compensatory effects and avoid pollution swapping. Further research must be carried out to check the validity of emission factors and modelling parameters at a national scale.

Egg fat is of considerable importance in the nutrition of the developing chick as a source of energy and essential fatty acids such as linoleic (18:2 n-6) and α-linolenic (18:3 n-3) acids. During incubation, yolk lipids provide fatty acids that are utilized for energy, synthesis of polyunsaturated fatty acids (PUFA)-rich membrane phospholipids, and eicosanoids by the embryo. Eicosanoids derived from n-6 fatty acid are more potent and pro-inflammatory than eicosanoids derived from n-3 fatty acids.

Two models of early life programming as affected by n-3 PUFA are investigated. Egg PUFA enrichment through breeder hen diet (pre-hatch or in ovo) or early post-hatch (within first 5 hours) feeding is investigated. Early access to nutrients (pre- and early post-hatch) is important because in broiler hatchlings that are selected for rapid early growth much of the immune system development occurs early in life. However, the current industry practice of feeding breeding hens diets high in n-6 fatty acids, limits the supply of essential n-3 PUFA in the hatchling. Early access to n-3 PUFA through in ovo or early post-hatch diet led to: (1) increase in the retention of n-3 PUFA in cell membranes, (2) reduction in plasma non-esterified fatty acids, (3) reduced production of pro-inflammatory eicosanoids, (4) suppression of cell-mediated immunity, and (5) alteration in cyclooxygenase-2 protein expression. The effects of an early exposure persisted from 14 to 35 days in different tissues and cells.

Given the fact that broiler birds are raised for 39 to 56 days, and that the effect of pre-hatch and early post-hatch nutrition persists for up to and over 36-47% of post-hatch life, using an early life programming approach will generate new knowledge about the role of maternal and early post-hatch diet in enhancing bird health and welfare.

Phytases have been used commercially since the early 1990s and have been the focus of considerable and sustained research for many decades. Despite this heroic effort there are still areas of persistent uncertainty such as the obscurity surrounding total compared with digestible calcium, appropriate modification to dietary sodium (and other electrolyte) concentrations, the usefulness of the amino acid and energy digestibility improvements and ultimately the effect of phytase on nutrient requirement. One further area which has attracted some attention recently is the effect of unconventionally high doses of phytase (i.e. >2,500 FTU/kg from Aspergillus niger or Escherichia coli) in an attempt to ostensibly ‘de-phytinise’ the diet. The effects of such ‘super’ doses of phytase can be considerable, and often beyond that which may be reasonably expected based on improvement in P digestibility per se. This review article addresses these effects and suggests mechanisms by which they may be explained.

The use of commercial exogenous enzymes in poultry diets is now a common practice. Broilers are predominantly fed pelleted diets; of the various unit operations in the production of pellets, grinding and conditioning are the components that can influence the efficacy of exogenous enzymes. The aim of this paper was to review the feed processing factors that influence the efficacy of exogenous enzymes in broiler diets. Recent studies have shown that the efficacy of exogenous enzymes is influenced by the degree of grinding. Available data suggest that enzyme responses on intestinal viscosity are more pronounced in feeds subjected to high conditioning temperatures. The issue of enzyme stability during conditioning and pelleting therefore becomes relevant and new enzyme technologies are being developed to overcome the high thermal processing issues. However, the effects of steam conditioning practices on enzyme stability have received less attention and need to be explored in future studies.

Excessive specialisation and production requirements place high demands on the metabolism of the broiler chicken. A number of metabolic problems, such as ascites, arise in chickens due to intensive selection to manifest their genetic potential for rapid growth. Ascites syndrome (Pulmonary Hypertension Syndrome) is one of the major causes of mortality and morbidity in modern broiler production today. Genetics, the environment, and management all seem to interact to produce a cascade of events that culminate in ascites syndrome. It is generally accepted that the high metabolic rate of current broiler lines causes an increased demand for oxygen, especially in cold environments or when birds are fed high nutrient density diets. In such situations, the relatively underdeveloped cardio-respiratory system of modern broilers fails to fulfil the required oxygen demand, which leads to hypoxemia, resulting in the development of pulmonary hypertension and subsequently ascites. Many nutritional, medicinal and management strategies have been proposed to alleviate the ascites. Higher levels of dietary vitamin C and E along with selenium might be beneficial, as they decrease the free radicals that are generated in birds with ascites. As the high metabolic rate (fast growth) is a major factor contributing to the susceptibility of broilers to ascites, appropriate selection strategies or feed restriction or light restriction in order to slow down the growth rate seem practically viable methods, since final body weight is not compromised. Optimisation of the house temperature and ventilation in cold weather seem helpful practices to decrease the incidence of ascites.

The article details the results of a quantitative survey which was carried out by personal interview of 3200 fresh chicken meat consumers ranging between 15 and 65 years of age and residing in the selected countries of Central and South-eastern Europe. A positive perception of fresh chicken meat was determined in all the countries sampled, with consumers reporting it as a tasty and healthy meat source. Special attention was devoted to the importance of meat origin in the purchase-decision-making process. The importance of fresh chicken meat origin in the purchase-decision-making process were evident in all analysed countries of Central and South-eastern Europe.

The reduction of the prevalence of zoonoses and zoonotic agents like campylobacteriosis and salmonellosis requires eradication, control and monitoring measures to protect both animal and public health. Therefore, it is important to identify the main sources of infections within the poultry production chain. As the latest EFSA results show, these zoonotic agents were mostly found on fresh poultry meat as well as in live poultry. Consequently, the main entrance paths have to be identified directly at farm level. Based on a literature review, the 112 risk factors for an introduction of Campylobacter spp. and Salmonella spp. infections were summarised and attributed to 14 risk categories such as farm management, biosecurity, staff hygiene and carcass handling. Afterwards, the main risk factors were identified by elicitation of expert opinion using the Delphi methodology. In the explorative study, an international expert panel defined and weighted the relative importance of the risk categories and risk factors within a three-stage procedure. According to the working hypothesis, risk factors related to hygiene in the poultry house as well as external service crews are the main determinants for infection. Based on the results an evaluation and assessment scheme for poultry farms will be developed. Furthermore, the results can help to assess the status of poultry farms, to raise awareness in farmers and their staff for relevant farm management techniques within education and training manuals.