44 CIRCULAR 905, U. S. DEPARTMENT OF AGRICULTURE- 
requirements are not consistently higher for the high-forage rations 
than for the high-grain rations. Differences in labor requirements 
for various rations fed a particular kind of livestock are small in 
comparison with differences among kinds of livestock. 
RisK AND UNCERTAINTY 
The risk and uncertainty associated with several utilization systems 
were measured in terms of the variability of returns from each dur- 
ing the 32 years from 1917 to 1948. The data show that variability 
of income differs very little for different grain-forage combinations 
fed a particular kind of livestock. Differences in variability of in- 
come associated with different kinds of livestock, however, were im- 
portant. Income from feeder cattle fluctuated a great deal more than 
returns from hogs or dairy cattle. Dairy cows showed the least vari- 
ability in returns. In judging which of the feeding systems is most 
desirable, a farmer may balance the prospective average returns over 
time against the variability of these returns from year to year in light 
of his own ability and willingness to bear risks. 
LITERATURE CITED 
(1) BERESFORD, REX 
1949. ONE HUNDRED AND FIFTY-ONE QUESTIONS ON CATTLE FEEDING AND 
MARKETING. JIowa Agr. Expt. Sta. and Ext. Serv. Bul. P 99, 
pp. 321-399, illus. 
(2) CuLBErRTSON, C. C., and others 
1951. DIFFERENT PROPORTIONS OF CORN AND HAY IN FATTENING LAMBS. 
Iowa Agr. Expt. Sta. A H Leafiet No. 178. (Processed.) 
(3)- Exais, N. R., ZELLER, J. H., and-Kine, J..H. 
1943. THE VALUE OF GOOD LEGUME HAYS IN THE RATION OF FALL PIGS. 
A. H. D. No. 60. 2 pp. U.S. Dept. Agr. (Processed.) 
(4) Heapy, Earw O., and JENSEN, H. R. 
1951. THE ECONOMICS OF CROP ROTATION AND LAND USE. Iowa Agr. Expt. 
Sta. Res. Bul. 383, pp. 420-459, illus. 
(5) ——, and OLson, RUSSELL O. 
SUBSTITUTION RELATIONSHIPS, RESOURCE REQUIREMENTS AND _ IN- 
COME VARIABILITY IN THE UTILIZATION OF FORAGE CROPS. Iowa Agr. 
Expt. Sta. Res. Bul. (In process.) 
(6) Horxins, J. A., GOODSELL, W. D., and Buck, R. K. 
1940. AN ECONOMIC STUDY OF THE BARBY BEEF ENTERPRISE IN SOUTHERN 
iowa. Iowa Agr. Expt. Sta. Res. Bul. 272, pp. 575-620, illus. 
(7) Iowa Agricultural Experiment Station 
1951. SEVENTH ANNUAL REPORT, SOIL CONSERVATION EXPERIMENTAL FARM, 
PAGE COUNTY. Iowa Agr. Expt. Sta. and Ext. Serv. FSR 88. 
(Processed. ) : 
(8) JENSEN, E., Woopwarp, T. E., and others 
1942. INPUT-OUTPUT RELATIONSHIP IN MILK PRODUCTION. U. S. Dept. 
Agr. Tech. Bul. 815, 88 pp., illus. 
(9) TROWBRIDGE, E. A., and DYER, A. J. 
1943. GooD PASTURE AND GOOD ROUGHAGE IN FATTENING CATTLE. Mo. Agr. 
Expt. Sta. Bul. 466, pp. 1-12. 
(10) Yooper, R. E. 
1945. RESULT OF AGRONOMIC RESEARCH ON USE OF LIME AND FERTILIZERS 
IN OHIO. Ohio Agr. Expt. Sta. Agron. No. 96,19 pp. (Processed. ) 
For sale by the Superintendent of Documents, U. S. Government Printing Office 
Washington 25, D.C. - Price 10 cents 
U. S. GOVERNMENT PRINTING OFFICE: 1952 
