Studies of the skeleton of the sheep. IV. The effects and interactions of dietary supplements of calcium, phosphorus, cod-liver oil and energy, as starch, on the skeleton of growing blackface wethers

Abstract

1. A factorial experiment on wether hoggs was carried out to examine the effects on bone growth and composition and on blood composition of four dietary factors. The factors were extra calcium, phosphorus, vitamin D, and energy in the form of starch, and each was fed in all possible combinations, so that there were sixteen dietary treatment groups in all. Each group consisted of three animals. 2. Serum calcium and blood inorganic phosphorus concentrations were determined monthly, and radiographs of most parts of the skeleton were taken at the beginning and end of the experiment. After about 6 months on the experimental diets the animals were killed and the ash weights and percentage of ash of different parts of the skeleton and of the whole skeleton were determined. Live-weight changes and food intakes were also measured.