Current strategies for sow feeding are based on maintenance of a constant body condition throughout the reproductive cycle by feeding at levels only slightly above maintenance in pregnancy and feeding generously for milk production in lactation. Recent evidence suggests that feeding at a low level during pregnancy, whilst meeting nutritional requirements, may be detrimental to sow welfare. The large intake capacity of the sow also offers opportunities for utilising cheaper, alternative feeds at this stage. If bulky feeds are available at low cost, it might be economically attractive to feed for fat deposition by the sow in pregnancy and utilise this during the subsequent lactation. This experiment was designed to investigate whether sows with increased body fat reserves at farrowing could be encouraged to utilise these efficiently during lactation by the provision of a high protein diet.