Animal Husbandry and Nutrition Florida Agricultural
Mimeograph Series No. 60-5 Experiment Station
SUPPLEMENTAL LYSINE FOR
GROWING-FINISHING SWINE FED A
CORN-SOYBEAN OILMEAL RATION I/
H. D. Wallace and G. E..Combs, Jr. 2/
Cereal grains and the common protein supplements used in swine feed-
ing are only fair sources of the important amino acid, lysine. Conse-
quently, lysine oftentimes Is the first nutritionally limiting amino acid
in swine feed mixtures. Until recently the cost of producing lysine com-
mercially was such that it was not economically feasible to supplement
practical swine rations. Lysine is now available at much less cost.
This has suggested the need for a reconsideration of the efficacy of
The study reported here was undertaken to ascertain the value of
different levels of lysine supplementation for growing-finishing swine
fed a corn-soybean oitmeal type ration.
Forty weanling pigs were divided into four similar lots of ten pigs
each on the basis of litter, weight, and previous treatment. The exper-
imental treatments were as follows:
Lot I Basal ration
Lot 2 Basal ration t .05% 1-iysine
Lot 3 Basal ration t .10% 1-lysine
Lot 4 Basal ration t .15% 1-lysine
The basal rations are presented in Table 1. All lots were fed a mixture
containing approximately 12.8% crude protein until they reached an average
weight of 125 Ib. The basal ration was then red,.ced -in protein level to
10.8e. The pigs were fed by self feeders in concrete confinement.
Auiomatic waterers provided fresh water at all times. During the finish-
ing period the animals had access to mist spray as needed for cooling
purposes. The experiment was initiated on May 2 and terminated on
July 25, 1959.
I/ This study was supported in part by a grant-in-aid from Merck and
Co., Inc., Rahway, New Jersey.
2/ Wallace and Combs, Associate and Assistant Animal Husbandmen
respectively, Florida Agricultural Experiment Station. The
assistance of W. E. Collins and L. S. Taylor, Swine Herdsman
is gratefully acknowledged.
Table I. Composition
Up to 125 lbs.
of Basal Rations
After 125 Ibs.
Ground yellow corn
Soybean oilmeal (44%)
Trace mineral mixture J/
Vitamin supplement 2/.
Antibiotic supplement 3/
/ Supplied the following to the rations in
Cu, 5; Co, 1.7; K, 7.8; and Zn, 25.
p.p.m,: Mn, 60; Fe, 73;
/ Contained 4000 mg. riboflavin, 4000 mg. pantothenic acid, 24000
mg. niacin and 104,000 mg. choline chloride per pound.
_/ Contained 5 gm. penicillin, 12.7 gm. streptomycin and 12.7 gm.
sulfa'quinoxaline per pound.
Results and Discussion
The summary of performance is presented in Table 2.
During the first forty-nine day period of the experiment the
control pigs (Lot 1) outgained all other lots. However, this superior-
ity largely disappeared during the final 35 day period. Gains over the
entire experimental period were very similar for Lots I, 2, and 4. The
poorer performance of Lot 3 (0.10% lysine) is not readily explainable.
All pigs in the lot performed satisfactorily; thus it would seem that
tho poorer gains were the result of chance allottment and not due to the
dietary treatment Imposed.
Feed utilization was excellent in all lots. During the early grow-
ing period the control pigs (Lot I) converted feed to gain the most
efficiently. During the finishing period Lots 3 and 4 (.10 and .15%
lysine respectively) were noticeably more efficient than the other two
lots. For the overall experimental period however, feed requirements
per pound of gain were very similar for all lots. Differences were
very small and it must be concluded that lysine supplementation at the
levels tested in this experiment did not exert a significant beneficial
effect on feed utilization.
An experiment involving 40 growing-finishing pigs has been con-
ducted to determine the supplemental value of three levels of I-lysine
(.05, .10 and .15 percent) when added to a well fortified corn-soybean
oilmeal ration fed in concrete confinement.
Results, measured in terms of daily gains and feed conversion,
indicated that none of the levels of lysine tested exerted a significant
Table 2. The Influence of Lysine Supplementation on the Gains
and Feed Conversion of Pigs Fed a Corn-Soybean Oilmeal Mixture.
Lot Number. I 2 3 4
Level of Lysine
Supplementation, % J/ 0.0 0.05 0.10 0 15
Number pigs 10 10 10 10
Avg. Initial wt. lb. 45.7 46.0 46.1 45.7
Avg. Final wt. lb. 190.6 191.9 185.4 193.7
Daily Gain, Ib.,
First 49 days 1.70 1.63 1.61 1.66
Last 35 days 1.77 1.88 1.72 1,91
Entire period 1.73 1.74 1.66 1.76
Feed required / Ib.gain, Ib.
First 49 days 2.66 2.82 2.74 2.78
Last 35 days 3.61 3.62 3.42 3.30
Entire period 3.07 3.18 3.04 3.02
1/ L-lysine monohydrochloride, supplied by Merck & Co., Rahway, New Jersey