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To what extent could water quality be improved by reducing the phosphorus content in animal feed?

Cow in field


Phosphorus is responsible for widespread water quality problems in Scotland. Animal feed (imported feed fed to commercial livestock) is known to contribute to this issue. Measures to reduce the phosphorus content of animal feed in Northern Ireland have reportedly helped to combat this issue. This project aims to find out the potential impact that phosphorus in animal feed is currently having on Scottish rivers and lochs; feasible ways of reducing the phosphorus content of the feed across the UK; and the beneficial effects that this would have on Scotland’s rivers and lochs.


Research requirement and specific objectives

  1. Estimate the potential contribution that phosphorus in animal feeds currently have on the phosphorus loads in Scottish rivers and lochs to determine if there is a problem and if so what is the magnitude and location of the problem.
  2. Identify the potential to reduce the phosphorus content of animal feed, including consideration of a similar approach to that taken in Northern Ireland. This should include details of the current phosphorus content of the main animal feeds.
  3. Identify the impacts on industry (manufacturers in terms of any extra costs associated with reducing phosphorus and also farmers in terms of any lost production, extra costs) for the approaches set out in ii). This should include advice on livestock nutrition to determine what sort of reductions of P in diets may be considered feasible from a production efficiency perspective.
  4. Estimate the potential impact that any measures set out in ii) would have on phosphorus loads in Scottish rivers and lochs.

Project Objectives