High-copper mineral mixture for fattening pigs.

Barber, Braude, Mitchell & Cassidy (1955, and unpublished work) have observed that the growth rate of fattening pigs can be enhanced by including in their rations a mineral mixture supplying 250p.p.m. copper in the diet. In order to substantiate these findings a field trial was carried out in which eight centres co-operated. At four of the centres two replicates of the test were run, so that altogether results from twelve replicates were available and are reported below. * Co-ordinator. t Biometrician.