Many decades of selection for increased egg output per bird and for efficient feed conversion have resulted in stocks capable of remarkable levels of performance. In the search for new ways to achieve further improvements in egg production efficiency, residual feed intake is seen as a parameter that merits the serious attention of breeders. This review examines relevant research relating to feed conversion efficiency since 1972 – including some results obtained by the author from commercial populations – and offers guidelines on the ways in which datd on individual feed intake could be applied within modern selection programmes.

Aerial emissions from poultry production may affect bird performance, cause respiratory ill health in stockmen and are a source of environmental pollutants. Recent measurements of the concentrations in, and emissions from, poultry houses are presented. Control of aerial emissions must be integrated with other environmental parameters that determine the profitability and sustainability of poultry production.

Haemorrhagic enteritis (HE) of turkeys is an economically important viral disease of turkeys, not only because it causes high mortality and immunosuppression, but also due to increased slaughterhouse condemnations. The disease is characterized by haemorrhagic enteritis and necrosis of lymphoid cells and a proliferation of reticuloendothelial cells in the spleen. In marble spleen disease (MSD), in addition to splenic changes, pulmonary congestion and oedema are also seen. Whereas splenomegaly in chickens (SMC) is characterized by lesions in the spleen similar to those of HE and the pulmonary lesions of MSD. The causative agents of HE of turkeys, MSD of pheasants and SMC are serologically indistinguishable group II Aviadenoviruses. All the three viruses can be propagated in lymphoblastoid cell lines derived from Marek's disease virus induced lymphoma in turkeys viz. MDTC-RP-16 and MDTC-RP19. The infection can be diagnosed by isolation and characterization of aetiological agents, serological tests such as the agar gel precipitation test, enzyme linked immunosorbent assay and the use of immunoperoxidase to demonstrate intranuclear adenovirus-like particles in infected cells shown by electron microscopy. The control of HE is possible by vaccination using avirulent MSD virus of pheasants as well as avirulent or attenuated strains of turkey HE virus.

Changes in broiler production parameters occur through a combination of genetic progress in the stock, improvements in management practices and flock health. Data from a comparative test conducted by Ross Breeders Ltd in 1994 involving commercial broiler stock and a control line established by them in 1976 showed that considerable improvement had been made in the rate of growth, feed conversion efficiency, yield and breast meat percentage during the 18 year period. Manipulations of lighting regimens have indicated that, under research conditions, it is possible to reduce the incidence of leg problems and total mortality, and on-farm experiments have demonstrated that profitability can be increased and flock health improved by the use of controlled feeding programmes and whole wheat feeding. In the future it is likely that feeding programmes, growth and the environment within large commercial broiler houses will be closely monitored by computers to produce optimum performance. It is vital, therefore, that trials in the future are conducted in facilities which allow the control group of birds to express their genetic potential to ensure that research findings are relevant to the broiler industry. The future of the broiler industry is difficult to predict but the use of in ovo vaccinations and novel feed ingredients, including targeted feed enzymes, is expected to increase whilst a better understanding of variability in wheat and the nutrient requirements of fast growing birds need investigation.

The principal source of eggs and meat in Bangladesh is the large population of indigenous free range scavenging rural poultry. However their performance is far below that of standard exotic stocks. An absence of varieties that are able to thrive well in the harsh hot and humid environment, poor nutrition and high incidence of disease in the rural areas are the main problems affecting poultry production. Under these conditions the standard exotic stocks suffer most from heat stress, malnutrition and diseases, while among the indigenous varieties Naked neck fowl perform better in terms of egg and meat production, and are more resistant to disease than their fully feathered counterparts. Crosses between indigenous Naked neck fowl and exotic standard breeds also perform better than similar crosses using fully feathered indigenous fowl. However, research has not yet been done to determine the potential usefulness of Naked neck birds in the development of stocks that are better adapted to the needs of the rural farming community. This paper brings together the available information on the performance of indigenous Naked neck fowl in the hope that it will draw the attention of scientists world wide to its interesting characteristics and facilitate future research. This could help in producing improved stocks better suited to the rural communities of Bangladesh and those in other countries where similar physical and socioeconomic conditions are to be found.