Poultry Development Review

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Poultry Development Review POULTRY DEVELOPMENT REVIEW The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO. ISBN 978-92-5-108067-2 (PDF) © FAO 2013 FAO encourages the use, reproduction and dissemination of material in this information product. Except where otherwise indicated, material may be copied, downloaded and printed for private study, research and teaching purposes, or for use in non-commercial products or services, provided that appropriate acknowledgement of FAO as the source and copyright holder is given and that FAO’s endorsement of users’ views, products or services is not implied in any way. All requests for translation and adaptation rights, and for resale and other commercial use rights should be made via www.fao.org/contact-us/licence- request or addressed to [email protected]. FAO information products are available on the FAO website (www.fao.org/ publications) and can be purchased through [email protected]. POULTRY DEVELOPMENT REVIEW Contents Foreword iii The role of poultry in human nutrition 1 The role of poultry in human nutrition 2 The nutritional benefits of chicken meat compared with other meats 4 The importance of poultry meat and eggs, especially for children and women 5 Increasing the nutrient content of chicken eggs to improve human health 6 The omega-3 fatty acids 7 How important is cholesterol in eggs? 8 Poultry and poultry products - risks for human health 11 Consumption 12 Marketing 15 Slaughtering and processing 18 Poultry housing and management in developing countries 23 Poultry housing and management in developing countries 24 Incubation and hatching 29 Brooding and management of young chicks 32 Housing and management of breeders 34 Housing and management of broilers 37 Housing and management of layers 39 Management and housing of semi-scavenging flocks 41 Poultry waste management in developing countries 45 Poultry waste management in developing countries 46 Poultry manure characteristics 50 Aerosol contamination 52 Location, siting and concentration of poultry units 54 Slaughterhouse wastes 56 Poultry feed availability and nutrition in developing countries 59 Poultry feed availability and nutrition in developing countries 60 Advances in poultry nutrition 64 Main ingredients used in poultry feed formulations 67 Feed supplements and additives 70 Alternative feedstuffs for use in poultry feed formulations 72 Animal feed safety 76 Poultry genetics and breeding in developing countries 79 Poultry genetics and breeding in developing countries 80 Contribution of indigenous genotypes to production and consumption of poultry meat and eggs 84 i POULTRY DEVELOPMENT REVIEW Commercial selection for meat and egg production 86 Genetic approaches to improved performance in sub-optimal conditions 89 Genetic diversity and conservation of genetic resources 92 Poultry health and disease control in developing countries 95 Poultry health and disease control in developing countries 96 Emerging pathogens of poultry diseases 101 Poultry disease diagnosis: field skills and laboratory procedures 103 Site biosecurity and supporting strategies for disease control and prevention 104 Veterinary roles in health and knowledge transfer across a poultry industry 106 Poultry welfare in developing countries 109 Poultry welfare in developing countries 110 Welfare issues in commercial egg production 114 Welfare issues in commercial broiler production 117 Transport and slaughter of poultry 119 ii POULTRY DEVELOPMENT REVIEW Foreword The poultry sector is possibly the fastest growing and most flexible of all livestock sectors. Driven primarily by very strong demand it has expanded, consolidated and globalised over the past 15 years in countries of all income levels. Livestock is fundamental to the livelihoods of about one billion of the world’s poorest people. Rural poultry, in particular, is essential for the livelihood of many resource-poor farmers often being the only asset they possess. It makes up about 80 percent of poultry stocks in low-income food-deficit countries and significantly contributes to: (i) improving human nutrition, providing food (eggs and meat) with high quality nutrients and micronutrients; (ii) generating a small income and savings, especially for women, thus enhancing the capacity to cope with shocks and reducing economic vulnerability; (iii) providing manure for vegetable garden and crop production. The importance of the socio-cultural and religious functions of village poultry production for smallholder livelihoods, beyond its economic or nutritional importance, is also widely recognized. This publication is a collection of short articles that give an overview of the benefits of poultry products and information about different aspects of their production. The articles are primarily written to provide information for a general audience rather than for technical experts in the concerned fields of specialization. Originally prepared as separate articles in 2011 for the FAO poultry production website they are compiled in this document for easy access and reference. iii POULTRY DEVELOPMENT REVIEW The role of poultry in human nutrition Poultry DeveloPment review • The role of poultry in human nutrition The role of poultry in human nutrition David Farrell, School of Land, Crops and Food Sciences, The University of Queensland, St. Lucia 4072, Queensland, Australia Chicken meat and eggs are the best source of quality protein, CHICKEN MEAT AND EGGS: A VALUABLE SOURCE and are badly needed by the many millions of people who live OF PROTEIN AND ALMOST ALL OF THE ESSENTIAL in poverty. In sub-Saharan Africa (SSA) and South Asia malnu- NUTRIENTS trition (poor nutrition) and undernutrition (inadequate nutrition) Chicken meat and eggs provide not only high-quality protein, but are closely associated with poverty. These conditions affect the also important vitamins and minerals. Worldwide, 2 billion peo- immune system. The HIV/AIDS epidemic sweeping through coun- ple depend on rice as their staple food. Most eat polished white tries in SSA stems partly from extreme poverty and, with it, poor rice stripped of many essential fats, the B complex vitamins and nutrition. several minerals. Other cereal grains are usually deficient in criti- cal nutrients. For example, maize (corn) is a staple food in some WIDE VARIATION IN CONSUMPTION OF POULTRY regions, but the niacin it contains is unavailable. Maize consump- MEAT AND EGGS tion without supplements causes pellagra. Invariably the protein A recent survey of several countries found that 34 percent of content of grains is low and of poor quality. Net protein utiliza- the people surveyed in South Asia and 59 percent in SSA were tion (NPU) is an index of protein quality, calculated by multiplying suffering from severe energy deficiency (Smith and Wiseman, protein digestibility by biological value. NPU of grains is generally 2007). Both groups obtained 67 percent of their energy from sta- less than 40. Rice is the exception, with NPU of about 60, but it is ple foods (cereal grains, grain legumes, starchy roots and tubers) low in protein (7.5 percent). NPU of chicken eggs is 87. Generally, containing small quantities of only low-quality protein. Their aver- cereals lack the most important amino acids for humans – lysine, age per capita egg consumption was only 42 per year, compared threonine, the sulphur-bearing amino acids (methionine and with a global average of 153. Stunting and wasting in children cysteine) and occasionally tryptophan. Eggs and chicken meat are under five years of age, and slow mental development were seen rich in these essential amino acids. mainly in rural areas of SSA. Eight out of ten of those affected Eggs are also high in lutein which lowers the risk of cataracts were among the poor. Diseases such as kwashiorkor and mar- and macular degeneration, particularly among people living in asmus, both seen in underweight children, are associated with developing countries. inadequate dietary energy and protein. Pregnant and lactating In the least developed countries, the projected increase in egg women and young children are particularly vulnerable. consumption between 2005 and 2015 is 26 percent, compared In SSA, only 8 percent of dietary energy comes from animal with only 2.4 percent in the most developed countries (Wind- protein, compared with an average of 17 percent in all develop- hurst, 2008). Corresponding annual projections for poultry meat ing countries, and 28 percent in China. are 2.9 percent and 1.6 percent, respectively (FAOSTATS). ADVANTAGES OF CHICKEN MEAT AND EGGS COMPARED TO OTHER ANIMAL PROTEINS In developing countries, the diet of people living in cities usually contains more animal protein than that of rural people, mainly because urban people are more prosperous, but also because they generally have access to a wider variety of foods at local mar- kets. In low-income
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