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Reducing nitrogen and phosphorus pollution by poultry - determining the potential for genetic methods - LS3104

The objective of the proposed research is to determine the degree of genetic variatio in nitrogen and phosphorus excretion by poultry and to provide indices for their assessment and reduction.

We calculate that poultry excrete about 130000 tonnes of nitrogen per annum in the UK alone. This figure is estimated from Defra statistics for the number of broilers, layers, turkeys, ducks and geese produced in 2000 - It is a conservative estimate, assuming an efficiency of utilisation of dietary nitrogen of 50%. Similarly, it can be calculated that broilers alone expel about 12000 tonnes of phosphorus a year. It is possible to develop methods for beneficial or at worst environmentally neutral disposal of these waste products but reduction at source is clearly of benefit both to the poultry producer and to the environment at large. A 10% reduction in excretion would reduce nitrogen and phosphorus pollution by respectively 13000 and 1200 tonnes per annum.

From previous work, we know that there is between-bird variability of nitrogen and phosphorus excretion. However, we do not know how constant the inter-individual variation is with time, or whether it is heritable. We need to measure: (1) the magnitude of individual variation, (2) the stability of the variation and (3) the heritability of the variation.

Minimisation of nitrogen and phosphorus excretion clearly reduces the release of wastes into the terrestial and aquatic environment. The important effects are in reducing pollution and eutrophication. In the case of nitrogen, a reduced output aslo has aesthetic benefits in the vicinity of poultry facilities. It also enhances the immediate environment of the birds, by improving litter quality and reducing atmospheric ammonia concentrations. The latter effect is also important in improving working conditions for farm personnel.

We consider that the proposal is relevant to Defra`s Science and Innovation Strategy (2003-03) in relation to the following aims: (1) to enhance the environmental sustainability of poultry production in the UK by minimising nitrogen and phosphorus losses from production systems; (2) to contribute to the economic sustainability of the poultry industries in relation to maximum efficiency of proten utilisation - amino acids are the expensive part of the diet; (3) to improve animal welfare by reducing nitrogen excretion and thereby improving litter quality and reducing the incidence of conditions such as hock-burn, sternal bursitis, focal ulcerative dermatitis and footpad dermatitis and by improving bone quality through improved phosphorus utilisation (4) to provide scientific data which can be used for poultry breeding and `precision agriculture`.
Time-Scale and Cost
From: 2003

To: 2006

Cost: £712,568
Contractor / Funded Organisations
Roslin Institute, Edinburgh (BBSRC)
Biotech-non GM              
Livestock Farming              
Natural Resource Use              
Sustainable Farming and Food              
Sustainable Production              
Fields of Study