Department of Animal Science Florida Agricultural
Mimeograph Series No. 63-1 Experiment Station
July, 1962 Gainesville, Florida
THE INFLUENCE OF SUPPLEMENTAL LYSINE
ON THE PERFORMANCE AND CARCASS CHARACTERISTICS
OF SWINE FED CORN-SOYBEAN MEAL RATIONS I/
H. D. Wallace, A. Z. Palmer, J. W. Carpenter,
R. L. Reddish and G. E. Combs 9/
A previous paper from this station (Animal Husb. Mimeo. Series No.
60-5) reported that .05, .10 or .15 percent supplemental 1-lysine did
not significantly affect performance of pigs fed a low protein, well
fortified corn-soybean meal ration. Carcass data obtained in that exper-
iment suggested a possible beneficial influence due to lysine additions.
It was that observation which prompted the experiment summarized herein.
The objectives were: (I) To study further the influence of supple-
mental lysine on performance and (2) Determine the effect of supplemental
lysine, if any, on carcass leanness.
Eighty weanling pigs of mixed breeding were divided into four similar
lots of twenty pigs each according to litter, weight and sex. During the
experiment the pigs were maintained in concrete confinement and self-fed
according to the following plan.
Lot No. No. Pigs Ration
1 20 Basal
2 20 Basal + 0.4% 1-lysine
3 20 Basal
4 20 Basal + 0.4% 1-lysine
The basal feed mixtures are presented in Table I. The pigs were fed
a basal mixture containing approximately 13.5 percent crude protein until
they reached an average weight of 125 pounds. At this time the crude
protein level was reduced to approximately 11.0 percent.
!/ This study was supported in part by a grant-in-aid from Merck and Co.,
Inc., Rahway, New Jersey.
2/ Wallace, Animal Nutritionist; Palmer, Assoc. Meat Scientist; Carpenter,
Asst. Meat Scientist; and Combs, Asst. Animal Nutritionist, Animal
Science Department, Florida Agricultural Experiment Station. R
Reddish, Associate Animal Husbandman, Florida Agricultural Ex
Service. The assistance of W. E. Collins and L. S. Taylor, Sline \
Herdsmen; Jeff Jeter, Meats Laboratory Manager and Mr. Richard Mman,
Laboratory Assistant is gratefully acknowledged. I 19U
V. ,19 ^2
Table 1. COMPOSITION OF BASAL RATIONS
Ingredient To 125 lb. wt. 126 lb. to market wt.
Ground yellow corn 82.20 87.70
Soybean oilmeal (50%) 13.00 7.50
Ground limestone 1.00 1.00
Steamed bonemeal I.00 1.00
Iodized salt 0.50 0.50
Trace mineral mixture 1/ 0.05 0.05
B-vitamin supplement 2/ 0.10 0.10
Vitamin B12 supplement 5/ 0.05 0.05
Antibiotic supplement A/ 0.10 0.10
Vitamin A and D supplement 5/ 2.00 2.00
i/ Adds following to ration (p.p.m.): manganese (29.6), iron (36.5),
copper (2.50), cobalt (0.83), zinc (42.0) and potassium (3.9).
2/ Contains 2000 mg. riboflavin, 4000 mg. pantothenic acid, 9000 mg.
niacin and 10,000 mg. choline chloride per pound of supplement.
2 Contains a minimum of 9 mg. 812 per pound supplement.
A/ Contains 10 gm. terramycin per pound supplement.
.2/ Contains 14 gm. vitamin A supplement (10,000 I.U./gm.); 4 gm. vitamin
D supplement (9,000 l.U./gm.) and 890 gm. ground yellow corn.
At the conclusion of the feeding experiment 10 barrows from each lot
were selected on the basis of weight and breeding uniformity and slaughtered
packer style for carcass study. Carcass weights and measurements were
taken after the carcasses had been chilled for 48 hours at 34-36 degrees F.
Length of the carcass was obtained by a measurement from the anterior edge
of the aitch bone (pelvis) to the anterior edge of the first rib. Backfat
thickness was calculated as an average of measurements taken at the first
rib, last rib and last lumbar vertebra. A tracing was made of the perimeter
of the lonoissimus dorsi muscle (loin eye), exposed by cutting the loin
perpendicular to the vertebral column equidistance between the tenth and
eleventh ribs. The area of the loin eye muscle was then determined by use
of a compensating polar planimeter. The carcasses were broken down by a
standard cutting procedure (Reciprocal Meat Conference, 1951). Percentage
of each lean cut was determined by relating the weight of the cut to the
weight of the live animal.
Results and Discussion
The feeding phase of the experiment is summarized in Table 2. An
examination of the performance data reveals that the lysine not only stimu-
lated gain in both of the supplemented lots but also permitted more efficient
feed conversion up to 125 pounds body weight. From 125 lb. live weight to
market weight the pigs did not respond to lysine supplementation. There
Table 2. THE INFLUENCE OF LYSINE SUPPLEMENTATION ON THE
FEEDLOT PERFORMANCE OF GROWING-FINISHING SWINE
Lot Number 1 2 3 4
Level Lysine Added, % 0.0 0.4 0.0 0.4
Number of pigs 20 20 20 20
Av. initial weight, lb. 61.9 61.4 61.3 61.4
Av. final weight, lb. 197.4 196.1 194.7 189.8
(Performance to 125 lb. body wt.)
Daily gain, lb. 1.49 1.58 1.53 1.58
SFeed per Ib. gain, lb. 3.11 2.92 3.19 2.91
(Performance from 125 lb. body wt. to market)
Daily gain, lb. 1.85 1.74 1.77 1.59
Feed per lb. gain, lb. 3.65 3.77 3.42 3.86
(Performance over entire period)
,Daily gain, lb. 1.69 1.68 1.67 1.60
Feed per lb. gain, lb. 3.43 3.39 3.32 3.41
Total days on feed 80 80 80 80
is some suggestion in the data that the 0.4% lysine may have actually inter-
fered with performance during the finishing phase of the experiment. The
performance data for the entire feeding period reveal no significant dif-
ferences in either gain or feed conversion.
Combined overall data for the 40 unsupplemented pigs give a daily
gain of 1.68 and a feed conversion of 3.38. Comparable values for the
40 lysine supplemented pigs are 1.64 and 3.40.
Data from the carcass study are presented in Table 3. The lysine sup-
plemented pigs exhibited less backfat and had longer carcasses. However,
these differences were very small. The percent of four lean cuts favored
the lysine supplemented animals by almost one percentage point. This dif-
ference was approaching statistical significance at the .05 level of
Table 3. THE INFLUENCE OF LYSINE SUPPLEMENTATION
ON THE CARCASS CHARACTERISTICS OF SWINE
No. animals 20 20
Av. slaughter wt., lb. 200.6 197.9
Av. backfat, in. 1.56 1.50
Av. carcass length, in. 28.94 29.15
Av. dressing percent 71.86 72.31
Av. percent ham 12.89 13.28
Av. percent loin 9.66 9.62
Av. percent picnic 6.19 6.24
Av. percent butt 4.24 4.48
Total percent 4 lean cuts 32.98 33.82
Av. loin eye area, sq. in. 3.33 3.41
Eighty weanling pigs were self-fed a corn-soybean meal type ration in
concrete confinement to determine the supplemental value of 0.40 1-lysine
on feedlot performance and carcass characteristics.
Daily gain and feed conversion were improved during the early growing
period up to 125 lb. live weight when lysine was added to the ration. From
125 Ib. to market weight the pigs did not respond to lysine supplementation.
The data suggested that this level of lysine may actually have caused inter-
ference with performance during the finishing phase of the experiment.
Carcass data showed a tendency toward leaner carcasses as the result
of lysine supplementation.
I. Wallace, H. D. and G. E. Combs. 1959. Supplemental lysine for growing-
finishing swine fed a corn-soybean oilmeal ration. An. Husb. and
Nutr. Mimeo. Series No. 60-5.
2. Reciprocal Meat Conference, Proceedings of the Fourth Annual. 1951.