Broiler meat is one of the sources of Salmonella contamination of humans. Concerns about food safety have prompted the poultry industry and governments to introduce control plans to combat Salmonella. This has been strengthened by legislation, as is the case in the EU, where targets have been set forcing member states to decrease Salmonella prevalence in poultry flocks. Strategies to prevent transmission of Salmonella to humans should focus on the whole production chain of broiler meat and on the subsequent storage and handling of meat, thus from farm to fork. In the primary production phase, both hygienic measures and general farm management strategies are important. These management strategies should include in-feed Salmonella control and product administration. A wide range of feed additives is currently available for that purpose. Hygienic measures and logistic slaughter are tools to reduce the Salmonella contamination in the slaughterhouse. At retail and in the consumer's kitchen, care needs to be taken of product storage and handling to avoid contamination and bacterial growth. The numbers of contaminated Salmonella broiler flocks will most likely decrease in the future due to the established action plans, but complete eradication of Salmonella is unrealistic. The main issue is, however, to keep the flock prevalence, the within-flock prevalence and the numbers of bacteria in infected animals at such a low level, that contamination of meat, and thus transmission to humans, becomes a highly unlikely event. This clearly underlines the need for coordinated action of governments and poultry-related industries (including feed industry and slaughterhouses), at all stages of the production chain.

Most nutritional studies with minerals have been carried out using dietary supplements, with little attention given to the role of those commonly found in drinking water. This is important since underground water supplies, which may contain high concentrations of dissolved salts, is a common source of drinking water for poultry in many countries. Recent evidence suggests that some minerals may exert adverse effects on the performance of growing broilers and laying hens when present in drinking water at concentrations similar to those found in other sources. Commercially farmed birds already receive a balanced diet and if they are also receiving high levels of nutrient as salt in the water in the form of sodium and chloride ions, then the performance of the birds may be negatively affected.

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.

The traditional feeding programmes and nutrient requirements of broilers, as established by the NRC, are usually based upon age and fixed growing duration. This is despite the fact that broiler growth pattern characteristics have changed enormously over last decade. Such classical approaches have been questioned as to their effectiveness, and it has been argued the NRC recommendations are no longer applicable to the present methods of production, and need to be re-evaluated. The short comings of traditional or classical fixed duration of feeding phases have led many investigators to suggest and introduce alternative feeding programmes in replacement, including alternative, phase, sequential, choice, dual and subsequent feeding. The effectiveness and shortcomings of such methods are analysed in this review.

An adequate supply of all nutrients, including proteins, fats, carbohydrates, vitamins, minerals and water, has to be provided to support maximum productivity of laying hens. Among these nutrients, vitamins are particularly important, since they are essential for optimum health as well as normal physiological functions of the hens. As most vitamins cannot be synthesized by poultry in sufficient amounts to meet physiological demand, they must be obtained from the diet. The absence from feed or impaired absorption or utilization of vitamins can lead to specific deficiency disorders. This review reports on the occurrence and the physiological functions of all vitamins and summarizes research related to the requirements for and the beneficial effects of supplemental vitamins for laying hens. The recommendations for dietary supplementation of vitamins from various organizations are compared and put into perspective of modern poultry genotypes and current husbandry conditions. As there is good evidence that the minimum dietary vitamin levels, required to prevent clinical deficiencies may not support optimum health, performance and welfare of poultry under today's conditions it is recommended to include a safety margin to the vitamin requirements of laying hens.

The current NRC recommendations for broiler chickens and laying hens are cause for concern within the animal feed industry, as they are based on very old trial data. This means the work was not only conducted with old-fashioned breeds of commercial chickens, but also relied on inorganic oxides and sulphates in feed and archaic diet formulation, with different quality and types of raw materials compared to those fed now. For modern poultry producers, these recommendations are so obsolete that they may be considered redundant for practical purposes. Broiler chickens and laying hens have benefitted from improvements in genetics and feeding practices since the 1950's and 60's, when many of the trials were run. They now also have the viable option of using chemically organic forms of minerals, which are known to be better absorbed, utilised and stored in tissues compared to inorganic ores. Since 2003, a program of research has been conducted comparing commercial organic minerals (Bioplexes®, Alltech Inc, USA) with inorganic forms, which monitored performance and excretion of minerals, as well as evaluating the new (lower) levels of organic minerals required for sustaining poultry performance. This large scale project began with a series of seminars, including one day on poultry, where global experts in this area discussed the problems and issues relating to mineral nutrition. A collection of the papers from these seminars were compiled and published (Taylor-Pickard and Tucker, 2005), and gave rise to a global project to redefine mineral nutrition. The following paper reviews the work completed to date, where chemically organic forms of minerals have been used in poultry diets.

2009 is turning out to be an interesting year, with the global recession hitting many countries, companies and individuals hard. However, it seems that agriculture has been somewhat (I use the word advisedly) unaffected in certain areas. Whether this is because of the major changes and efficiency measures that the industry undertook in the past decade, or because of food shortage issues, is hard to say. Although many countries have seen turmoil in their poultry industry, others appear on the up, which is good news in those quarters. The demand for efficiently produced, safe and healthy meat and eggs continues unabated, although it seems likely that the high end of the market will be affected in affluent countries that have been hardest hit in the recession. Predictions have been voiced regarding the increased demand for cheaper, healthy food, which has been a major focus of poultry production for a long time. However, from the media, the global recession is still very much in a ‘wait and see’ state. Let’s hope that our industry comes out of it stronger, whatever guise that may take.

In the WPSJ world, things have been getting busy! I have seen more and more unsolicited papers coming across the editorial desk, which has been very good news. The latest figures regarding our citation index made very good reading recently too – we are on the up again with a rating of 1.398, a 0.125 increase over last year. For those of you who aren’t familiar with these figures, these ratings relate to the number of times each paper is cited in other published work. The higher the rating, the more authors want to use the journal for publishing papers. However, this greater flow of manuscripts and increased interest in the journal has meant some unavoidable delays in processing papers – so I would like to take the opportunity to thank any authors that have seen some delays for their patience in this matter.

It’s been a good year for WPSA meetings too – the eagerly awaited European Nutrition Symposium will be held in Scotland in August, and will also host the annual board meeting. Other meetings include the new Mediterranean meeting, the Finland conference and targeted Working Groups, such as genetics being held later this year. The reports from these will be available in the December issue, for those of you who couldn’t make it. For those of your who will be there – do come and see us on the WPSA stand in Scotland and give us feedback on the journal and what you get out of it. We are always happy to see members, and encourage new membership.

Lucy Tucker

Editor

It has been about 80 years since Cu was first recognized as being important for maintenance of haemoglobin. Since that time requirement values have been established and signs of deficiency and excess well documented. NRC (1994) provide the most comprehensive list of detailed requirement values for Cu for various classes of poultry, yet these lack extensive detail and are predicated on just five publications, the most recent of which was conducted 30 years ago. Requirement values average 6-8 ppm which traditionally is supplied by inorganic salts and especially copper sulphate. Other inorganic sources vary from 40-115% bioavailability of Cu compared to sulphate. Copper is easily complexed with amino acids or proteins, leading to the development of so-called organic sources of copper which are claimed to have better digestibility and/or less formation of insoluble complexes with other minerals in the digesta. Results on effectiveness of organic vs. inorganic forms of Cu are variable, although this line of research has led to appreciation of the potential to use much lower levels of supplementation. Since at least 80% of dietary copper appears in the excreta, using lower levels of diet supplementation means reduced Cu in the environment. With less supplementation, knowledge about bioavailability of Cu in major feed ingredients becomes important. Copper in cereals is reported to be 80% available to the bird while that in vegetable proteins is closer to 50% available. Availability from animal proteins is very variable, while corn distiller's grains now provides the most concentrated source of Cu within the major ingredients. Copper levels greatly in excess of requirement, at around 125 ppm, have been shown to improve performance of meat birds and egg layers. The mode of action is unknown although likely relates to antibacterial properties of Cu. Likewise high levels of diet Cu have been shown to reduce cholesterol content of eggs and poultry meat, although this is often at the expense of loss in performance and contribution of more Cu to the environment.

This paper estimates the economic costs of Highly Pathogenic Avian Influenza (HPAI) to the poultry industry at the farm and sub-sector levels, and examines the benefits of controlling and preventing the spread of HPAI in Ghana. The scare in 2006 and outbreaks in 2007 have affected consumption of poultry products such as chicken meat and eggs, which sharply dropped by 51% and 64%, respectively. Economic losses due to the HPAI threat, and outbreaks to rural and commercial poultry producers, including those of egg and live bird sellers, have been estimated at US$26.3 million. These losses are due to the destruction of infected eggs and day-old chicks and a drop in market prices (of up to 25%) of day-old chicks and eggs.

A total of 40,727 birds from 35 farms died due to HPAI, of which 33% died naturally of the disease and 66% were culled. The Ghanan government spent US$160,000 in compensation paid to producers of culled birds; expenditures for containment of the disease at source and control measures to minimize risk of HPAI such as depopulation, decontamination. A ban on movement of poultry products between 2006 and 2007 amounted to US$ 4.3 million. These control measures eventually prevented the country losing 99.88% of its poultry stock, avoided economic losses valued at US$ 416 million.

Campylobacter are the primary cause of food poisoning in the UK and many other countries so, because chicken are recognised as one of the main routes by which this organism gets into the human food chain, there is considerable interest in identifying potential sources of Campylobacter on the farm. One potential source of infection is water, which may also be a means by which the organism is transmitted through the flock following initial infection. Studies into the role of water in Campylobacter infection of chickens have identified the importance of factors such as biofilm in protecting the organisms and, potentially, the viable but non-culturable form (VNC) of Campylobacter. While difficulties in identifying the VNC form in field outbreaks may have led to an underestimate of the importance of water as a risk factor there are contradictory views regarding the ability of the VNC form to cause infection under field conditions. Producers may treat drinking water with a range of products to reduce the number of microbial contaminants, Campylobacter included, that reach the growing bird in the drinking water. Examples of products used by producers include chlorine, chlorine dioxide, organic acids, peracetic acid and hydrogen peroxide. The efficacy of these products differs depending on the environment in which they are used, pH for example having a significant effect on the efficacy of chlorine. If the full benefits of drinking water treatment are to be realised then further evidence is required, in terms of the effects on the normal production parameters such as weight gain, feed conversion efficiency, flock uniformity as well as on the prevalence of infection such as that caused by Campylobacter.

Hexamethyl-p-rosaniline chloride (HRC), also known as crystal violet or gentian violet, is a water soluble, triphenylmethane dye with bacteriostactic, fungistatic and antihelminthic activities. It has a wide range of uses, from a treatment in humans to an additive for poultry feeds. In the poultry industry, this compound has been proven as a fungicidal agent in feed, a selective bactericide against gram-positive bacteria, and has demonstrated inhibitory effects against the activity and infectivity of various strains of viruses including Newcastle disease and fowl-plague virus. At normal inclusion rates (0.5 to 1 kg/MT final feed), commercial products such as GV-11 (Naremco, Inc.) failed to be detected in broiler meat. High levels of consumption of gentian violet can be toxic to animals, with the single dose LD50 for GV-11 determined to be between 2.5 and 5.0 g/kg body weight.

The production of copra meal in some parts of the world is abundant and cheap and hence its inclusion in poultry diets would benefit the poultry industry. Its use as a feeding material would also be beneficial for the coconut industry and the environment, through the reduction of copra waste. However, the nutritional and physical qualities of this by-product are poor, and consequently, there has been limited use of this material in poultry diets. Attempts to improve the quality of this feedstuff have been made through supplementation with amino acids and enzymes as well as physical treatments such as pelleting, soaking and grinding. This paper reviews some issues of using copra meal as a poultry diet and aspects of dealing with the problems.

The effect of phytate and phytase on the bioavailability of phosphorus has been appreciated for many years and phytase has been exploited commercially since the late-1990s to considerable global success. Although a number of authors have reported improved digestibility of amino acids, energy and other minerals (most notably calcium) by the addition of phytase to poultry diets, these so-called ‘extra-phosphoric’ effects of phytase are less well understood. Recent work has shed light on the underlying mechanisms by which phytase influences the apparent digestibility of amino acids, energy and minerals and much of the improvements are thought to be related to enhanced absorption of exogenous and re-absorption of endogenous amino acids. The synthesis and loss of endogenous protein is nutritionally expensive for animals and is negatively correlated with metabolisable energy, net energy, and the digestibility of nitrogen and amino acids. It has been estimated that as much as 50% of the total nitrogen present in the small intestine during digestion is of endogenous origin, resulting in negative digestibility coefficients in the proximal small intestine. Clearly the successful resorption of the secreted protein in the small intestine is critical to maintain favourable nitrogen balance and most endogenous proteins will eventually be digested and absorbed. However, a considerable proportion of endogenous secretions leave the terminal ileum and represent a net cost to the animal, the environment, and, importantly, to the poultry producer. Thus, dietary anti-nutrients that induce secretion and/or impair absorption e.g. tannins, trypsin inhibitors, or phytate can have substantial adverse consequences for productivity. The measurement and nutritional significance of endogenous losses in poultry, specifically with regard to the effect of phytate and phytase, are examined in the current review, in an attempt to explain the extra-phosphoric nutrient matrices assigned to commercial phytase products.

Poultry, unlike humans, have a fourth retinal cone that allows them to see in the UVA part of ultraviolet radiation. This ocular function is principally used by poultry to modify various behavioural functions such as feeding, peer recognition, mate selection, mating activity, and social encounters. Retinally perceived UVA controls the release of melatonin in the pineal gland of dark-adapted birds. Ultraviolet radiation has shorter wavelengths than visible light, and, as a result, is unable to penetrate to the hypothalamus to induce a photosexual response; UV is thus minimally involved in avian reproductive function. UVA and UVB have anti-rachitic properties which catalyse the synthesis of vitamin D3 from 7-dehydroxycholesterol in the skin of feet and legs, a function that prevents rickets, minimises the incidence of tibial dyschondroplasia, and normalises growth and bone ash in young birds fed diets deficient in vitamin D3; surprisingly, there is sufficient UVA in white fluorescent light to produce these benefits. UVC from the sun is filtered out by the atmosphere's ozone layer, so does not occur in sunlight, but artificially produced UVC has germicidal properties and has been shown to protect domestic fowl from aerogenic viral infections, however, vaccination has made this property superfluous to the modern poultry industry. Recently, the introduction of lamps that emit both visible light and UV has made the provision of UVA to poultry a practical proposition, and so it is opportune that the responses of poultry to UV radiation are reviewed and its relevance to modern poultry production assessed.