Oilseed rape is a protein crop that can be readily grown under UK conditions and has a good amino acid profile relative to other plant protein sources. Its use in diets for young pigs has been limited by concerns about its content of anti-nutritive factors, especially glucosinolate compounds, although these have been progressively reduced by plant breeders (Gill and Taylor, 1989). The whole seed contains a high level of digestible oil, making it an excellent energy source for piglets provided that the oil is made available by milling or heat treatment to rupture the seed coat. The forthcoming ban on use of in-feed anti-microbial growth promoters has renewed interest in rapeseed use because glucosinolate compounds can have antimicrobial effects (Fenwick and Heany, 1983), and because weaning age may be increased in future to reduce risk of health problems. In this circumstance, where regular intake of solid feed is established during lactation, the sensitivity to dietary rapeseed in the post weaning stage may be less critical. This experiment therefore evaluated the response in performance and health indicators of piglets weaned at different ages to diets with different rapeseed inclusion levels.