Animal Science Florida Agricultural
Mimeograph Report No. AN68-3 Experiment Station
August, 1967 Gainesville, Florida
INFLUENCE OF VARIETY AND HEATING ON THE NUTRITIVE VALUE
OF FULL-FAT SOYBEANS AS A PROTEIN SUPPLEMENT FOR FINISHING LAMBS
P. E. Loggins and C. B. Ammerman1/
Appropriate heating of soybean meal and cottonseed meal has been shown to
improve their nutritive value for ruminants (Woods et al., 1962; Tillman and
Kruse, 1962; and Sherrod and Tillman, 1962, 1964). Dysli et al. (1967) reported
that heating full-fat soybeans increased the net nitrogen utilization when fed to
sheep. In the same studies, when full-fat soybeans were fed as supplemental
protein for finishing lambs, there was a significant linear increase in average
daily gains as the heating time for the soybeans increased from 0 to 30 minutes.
The purpose of the present study was to: (1) compare two varieties of full-fat
soybeans as a source of protein for finishing lambs and (2) obtain additional
information on the influence of heating on the feeding value of full-fat soybeans.
Full-fat soybeans of the Adams and Hardee varieties were ground through
a one-fourth inch screen in a hammer mill and a portion of the Hardee beans
autoclaved at 121 C. and 15 lbs. per sq. in. of steam pressure for 30 minutes.
The heated beans were dried to an air dry basis and reground for mixing with
other dietary ingredients. The soybeans were mixed in rations as shown in Table 1.
Table 1. Composition of Rationsi/
Autoclaving time, min.
Ingredients 0 0 30
Snapped corn, ground 75.00 75.00 75.00
Soybeans 14.54 15.28 14.58
Corn starch 8.96 8.22 8.92
Defluorinated phosphate (18%P, 35%Ca) 1.00 1.00 1.00
Salt, trace minerallred2I 0.50 0.50 0.50
Vitamin A, D, and E-' + + +
100.00 100.00 100.00
I/ All soybeans ground in a hammer mill using a 1/4 inch screen. Heated beans
were autoclaved at 1210 C. and 15 Ibs. of steam pressure, dried, and reground
2/ Listed minimum analysis in percent: Fe 0.27, Mn 0.25, Cu 0.33, Co 0.01,
Zn 0.005, I 0.007 and NaC1 95.9.
3/ 2000 I.U. vitamin A palmitate, 270 I.U. vitamin D2 and 5 mg. DL-alpha
tocopherol were added per pound of ration.
I/ Loggins, Associate Animal Husbandman; Ammerman, Associate Animal Nutritionist;
the assistance of J. U. Stokes is gratefully acknowledged.
The rations were formulated to contain 12% total protein, with approximately 51%
of this amount supplied by soybean protein. The protein level of the soybeans
and mixed rations is shown in Table 2.
Table 2. Protein Content of Soybeans and Mixed Rations
Autoclaving time, min.
Item 0 0 30
Soybeans-/ 47.2 43.7 ---
Rations2/ 12.1 11.9 11.6
I/ Expressed on dry matter basis.
2/ Expressed on a 90% dry matter basis.
Thirty-three Florida native and Rambouillet weanling, ewe lambs with an
average initial weight of 70.6 lbs. were group fed for 78 days in a summer feeding
trial. The lambs were randomly allotted to treatments according to breeding with
five Rambouillet and six Florida native lambs fed each of the three experimental
rations. The experiments were conducted in a pole-type barn that provided ade-
quate shelter. The rations were hand fed twice daily according to appetite and
then refused feed was weighed back every few days as required. Feed intake was
recorded, and the lambs were weighed initially and biweekly thereafter. Individual
final slaughter grades were determined by two experienced graders at the end of
the feeding period.
Protein determinations on the soybean and ration samples were made according
to A.O.A.C. (1960) methods. The data for average daily gains and slaughter grades
were tested for treatment effects by analyses of variance as described by Snedecor
Results and Discussion
The results obtained in this study are shown in Table 3. The unheated soy-
beans of the Adams and Hardee variety responded similarly as sources of supplemental
protein for finishing lambs. The lambs gained an average of 0.29 and 0.30 Ibs. per
head daily on the two varieties, respectively. Although not significantly different,
lambs fed the heated Hardee soybean gained an average of 0.33 compared with 0.30
Ibs. per head daily for those fed the unheated beans of the same variety. This
suggested an improvement in animal performance similar to the increased gains due
to heating which have been previously reported. Dysli et al. (1967) reported that
unheated Hardee soybeans resulted in an average daily gain of 0.30 by lambs com-
pared with 0.37 Ibs. per head daily for lambs fed beans of the same variety which
had been heated for 30 minutes. In the present study, the requirement per pound
of gain varied from 8.3 to 8.7 pounds of feed and was slightly less than that
reported by Dysli et al. (1967) when a similar ration was fed. The average slaugh-
ter grade was medium choice or slightly less and was not significantly influenced
The results obtained in this trial suggesting an improvement in animal per-
formance when full-fat soybeans are heated prior to feeding are similar to those
found in other experiments in which the heat treatment of cottonseed and soybean
meal has been shown to improve their utilization as protein sources for ruminants.
Table 3. Effect of Variety and Length of Heating on the Nutritive
Value of Soybeans for Growing Lambs
Autoclaving time, min.
Item 0 0 30
No. Lambs 11 11 11
Initial wt., lbs. 70.1 70.9 70.8
Av. daily gain, Ibs. 0.29 0.30 0.33
Feed/unit gain 8.7 8.3 8.7
Final grade/ 13.0 12.5 12.6
i/ Low, medium, and high choice slaughter grade represented by 12, 13, and 14,
The comparative nutritive value of soybeans of the Adams and Hardee varieties
and the effect of heating soybeans of the Hardee variety were studied in a 78-day
finishing trial with weanling lambs. Lambs fed the Adams and Hardee variety of
soybeans which supplied 51% of the total dietary protein gained 0.29 and 0.30 lbs.
per head daily, respectively. Although it was significantly different, lambs fed
Hardee beans which had been heated for 30 minutes gained 0.33 compared to 0.30
pounds daily for those lambs fed the unheated beans of the same variety. This
suggested a small improvement from heating the beans.
1. A.O.A.C. 1960. Official Methods of Analysis (9th Ed.) Association of Official
Agricultural Chemist. Washington, D. C.
2. Dysli, R. R., C. B. Ammerman, P. E. Loggins, J. E. Moore and L. R. Arrington.
1967. Effects of steam-heating upon the nutritive value of full-fat soybeans
for sheep and rats. J. Animal Sci. 26:618.
3. Sherrod, L. B. and A. D. Tillman. 1962. Effects of varying the processing
temperatures upon the nutritive values for sheep of solvent-extracted soybean
and cottonseed meals. J. Animal Sci. 21:901.
4. Sherrod, L. B. and A. D. Tillman. 1966. Further studies on the effects of
different processing temperatures on the utilization of solvent-extracted
cottonseed protein by sheep. J. Animal Sci. 23:510.
5. Snedecor, G. W. 1956. Statistical Methods (5th Ed) The Iowa State College Press,
6. Tillman, A. D. and K. Kruse. 1962. Effect of gossypol and heat on the digesti-
bility and utilization of soybean protein by sheep. J. Animal Sci. 21:290.
7. Woods, W. R., H. Richardson, K. Kruse, W. D. Gallup and A. D. Tillman. 1962.
Further studies on the nutritive value of cottonseed meals for ruminants.
J. Animal Sci. 21:284.