Nutritive value of cereal and cassava diets for growing and fattening pigs in Nigeria.

In a previous report (Oyenuga & Opeke, 1957) the nutritional and economic importance, real and potential, of cassava root (Manihot utilissima Pohl) to man and in livestock production in Nigeria was stressed. Cassava is not only the most widely grown vegetable in Nigeria (it accounted for nearly 50% of the total root crops produced in the country in I ~ ~ o I ) , it is also the most productive farm crop, yielding edible nutrients equivalent to an average of over 13 million kcal/acre compared with 9 million from yam (Dioscorea sp.), I million from guinea corn (Sorghum vulgare Pers.) and I million from maize (Zea mays L.). It is therefore the cheapest source of calories for man and livestock in the country. Information on the chemical constituents of cassava root is scanty. Its nutritive value and the availability and metabolic usefulness to farm animals of its more important chemical constituents are little known. It would appear that qualitative and quantitative studies of some of its more important chemical constituents and of the requirements of the animal body for them would contribute to a clearer appraisal of its nutritive value for livestock. In the experiments reported now the nutritive value for pigs of raw and boiled cassava roots was compared and, in the first experiment, both forms of cassava were compared with a standard guinea-corn diet. In the second experiment the metabolism of nitrogen, calcium and phosphorus in growing pigs fed on raw or boiled cassava was studied. The second experiment also compared the effect of the simple mineral mixture hitherto included in diets used in this Department with a commercial I.C.I. iodized mineral mixture.