Published online by Cambridge University Press: 02 September 2010
The availability of Ca and P in the young growing pig was determined by the use of a radioisotopic technique. Eighteen Large White barrows of 25 kg mean body weight were used in the study, 10 being fed 1·20 kg per day of a cereal-based diet and the remainder half of this amount. At the higher dietary level the intake of Ca was 9·4 g/day, and that of P was 9·7 g/day. The mean availabilities of Ca and P were 41·5% and 78·1% respectively. At the lower level of intake there was no significant change in the availability of either element, mean values being 39·6% for Ca and 82·5% for P. These values contrast markedly with the 67% for Ca and 50% for P currently used in the calculation of dietary requirements for the elements by the factorial approach.