Abstract
Two experiments, I and II, were carried out with 15 piglets (hybrids of Landrace × Yorkshire) approximately 60 days old. Six piglets were used for experiment I and the other nine for experiment II. The former were fed a high lysine diet, and the latter a low lysine diet for 4 months. DL-methionine and P/Ca ratio were formulated to meet the levels recommended by the National Research Council, U.S.A., in 1973. The nutrient contents and amino acids of the diet were made as much the same as possible for the two control groups of experiments I and II. The 9th right costochondral joint was selected in all the animals for the present study, because it exhibited more characteristic lesions than any other site examined. The results obtained are summarized as follows. (1) Growing piglets fed a high lysine diet revealed, as a whole, relatively mild disturbances in the ossification process of the costochondral joint. (2) Growing piglets fed a low lysine diet revealed, as a whole, marked disturbances in the ossification process of the costochondral joint.
