Many studies have assessed use of the outdoor ‘range’ area on free-range laying farms, and have revealed that percentage range use at any one time rarely exceeds 50% of the flock, and is sometimes below 10%. What constitutes a ‘good’ range use is difficult to determine without better knowledge of ranging bout lengths under ideal conditions. Well documented factors that affect percentage range use include prevailing weather, flock size and shelter on the range. Other factors such as pophole design, internal and external stocking density and system design appear to play a role although their effects are not as clear and more research would be valuable to truly understand their relevance. Factors affecting bird distribution on the range are also reviewed.

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.

Natural killer (NK) cells are part of the innate immune system and are classified as large granular leukocytes. In this review, a functional and repeatable protocol to measure NK cell activity in avian blood samples is discussed. The cell line LSCC-RP9, a retrovirus transformed B cell line, is used as the target cells. The basic methodology involved incubation of effector cells, containing NK cells, with labelled LSCC-RP9 cells. A red fluorescent DNA dye (propidium iodide) was added to label the target cells that had their plasma membrane permeabilised by NK activity. Results were analysed by flow cytometric technique to determine percent cytotoxicity of various effector to target cell ratios. The cells that showed both red and green fluorescence were the dead target cells. Three other cell populations were also visible: live target cells (green), live effector cells and dead effector cells. Based on this technique, immunomodulation in NK cell activity due to factors such as nutrition or environment can be determined in different species, including avian species.

Zinc (Zn) is an important nutrient in poultry and its deficiency has been linked with various disorders, in addition to depressed growth and performance. It is now recognised that Zn has a major role in antioxidation, growth and development, production, immunity and stress related issues. Supplementation of Zn can improve growth, augment immunity, enhance antioxidant capacity, increase endocrine secretion and interact with other minerals in the gut. In this review, some of the basic information regarding the importance and activity of Zn within the body and the addition of Zn in poultry diets is discussed.

Currently, synthetic methionine (Met) use in organic poultry diets in the United States is limited to 1, 1, and 1.5 kg per metric tonne of feed for laying hens, broilers, and turkeys and other poultry, respectively. This limitation, and the push to ban the use of synthetic Met entirely, makes it challenging to formulate diets to meet the requirements of these birds. Methionine levels can be maintained in organic poultry diets without synthetics by dramatic increases in dietary crude protein; however, the ramifications of such high crude protein intake are major increases in feed cost and environmental concerns due to increased nitrogen excretion, rises in ammonia emissions, and subsequent welfare issues. This review examines alternative bird genetics and feeding strategies that have the potential to reduce or eliminate the need for synthetic Met in organic poultry diets. Alterative ‘heritage’ breeds may have lower Met needs as a percentage of the total diet; however, these birds have substantially slower growth and are less productive compared to typical commercial breeds. Feeding strategies that have been examined to reduce Met inclusion in the diet, such as allowing birds to forage, providing low Met density diets to encourage increased feed intake and subsequently make up for the Met deficiency, allowing birds to self select between energy-rich ingredients and protein concentrates to meet their Met needs by instinct, or supplementing methyl donors (betaine or choline) or inorganic sulphate, have been shown to make up for marginal Met deficiencies in some instances. However, there is no one solution to this issue that has been found thus far. A combination of genetics, feeding strategies, and alternative ingredients may provide the most favourable solution in the future.

Poultry production has experienced tremendous change in Egypt in the last three decades. Small-scale family poultry production, otherwise termed household poultry, was part of this transformation but to date no concise description has been made of Egyptian household poultry. In this report, this is described using surveys and reviews. Inputs and outputs of this production system were evaluated and the profitability of the household poultry was estimated. Household poultry contribute immensely to food security in Egypt; providing income for individual families. A mean flock size of 73 (mixed breeds) was determined and this yielded a net annual profit of 2287.67LE (US$397.34) per annum. The important household poultry diseases are principally viral and bacterial. While Egyptian household poultry are similar to others in Africa in terms of multi-species flocks, women-driven projects, labour and marketing structures, it differs in input systems, hatchery method, disease management, and other indices. Suggestions for improvement of this sector of the poultry industry are offered.