The Japanese Cattle has a wide width of variability in the performance of meat production. Therefore, to rearize high profits on farm of fattening cattle, the operator's competence is highly appreciated in selecting stock cattles' buy. But, as the performance of meat production is each cattle, in fact, can be revealed only after considerable progress of feeding, so the farmers must be highly skilled in feeding and management according to the variabilities of stock ones: the ration must be adjusted individually to each stock of the lot, and self-feeding-system has not been adopted.
Nevertheless, on the farms of fattening cattles the details of the profits, due to the lack of uniformity in meat production, have not been cleared up until the present time.
In this paper, the profits of fattening cattle per diem and their correlations to the prices of stock ones are accounted for one year on one of the farm of the largest size keeping Japanese Cattles in Hiroshima Prefecture (see Fig. 1, Table 8).