Department of a Science Florida Agricultural
Mimeograph Se ieNo. N70-11 Experiment Station
May, 1970 Gainesville, Florida
LEVEL COPPER AS A GROWTH
SULANT FOR FINISHING HOGS1/
/. Wallace, G. E. Combs and E. W. Lucas2/
The r ical minimum requirement of swine for copper has not been adequately
defined; however, it is generally accepted that 5-10 ppm in the diet is
sufficient for all classes of swine. The use of higher levels of copper (125-
250 ppm) as a growth stimulant has been studied extensively during the past
fifteen years. A compilation of the many experiments conducted between 1955 and
1967 was made by Wallace (1). This report emphasized the effectiveness of high
level copper and the feasibility of using copper as a routine feed additive.
These experiments demonstrated that young pigs respond more dramatically to
copper supplementation than do older pigs. Also there was a clear tendency for
copper fed pigs to lose much of the early advantage when fed copper continuously
throughout the growing-finishing period.
This study was designed to obtain performance response data to copper
supplementation using older pigs which had not previously been fed high levels
of copper.- The main object was to determine if healthy, thrifty pigs would
respond to a level of 125 ppm copper as copper sulfate during this less
critical period of the production cycle.
The study consisted of two trials conducted simultaneously but with no
direct replication intended. The first trial (trial 1) involved a total of
thirty-six crossbred barrows (Duroc, Yorkshire and Hampshire). The animals
were divided into similar groups of eighteen pigs each, based on weight and
litter. These animals were fed in concrete confinement and one group was
supplemented with high level copper. The other trial (trial 2) involved
forty-eight gilts from the same litters as the barrows of trial 1. They were
also divided into two groups as in trial 1 but were maintained in 1/2 acre dirt
lots during the course of the trial.
I/Supported in part by a grant-in-aid from International Copper Research Associa-
tion, Inc., New York, New York. Grateful acknowledgement is also given Chas.
Pfizer & Co., Terre Haute, Indiana for supplying the vitamin mixture and
Calcium Carbonate Company of Ouincy, Illinois for supplying the trace mineral
2/Wallace and Combs, Animal Nritriioniqts and Lucas, graduate assistant, Depart-
ment of Animal Science.
All pigs were self-fed and water was provided by automatic watering devices.
Both trials were initiated on October 28, 1969. On January 19, 1970 three
of the heavier pigs in the control pen and four of the heavier pigs in the copper
supplemented pen were weighed off test in trial 1. On.January 22, 1970 eight of
the heavier pigs in the control pen and,six of the heavier pigs in the copper
supplemented pen were weighed off test in trial 1. On January 28, 1970 the .
remaining pigs of trial 1 and all pigs of trial 2 were weighed off test. Thus
the gilts of trial,2-averaged a few more days on test than the barrows of .
The basal feed-mixture is presented in Table 1. Gain data were analyzed for
statistical significance using the analysis of variance procedure.
Results and Discussion
The results of the study are summarized in Table 2. As previously pointed
out the two trials were not intended to be designed replications so there is
little purpose to be served by making a comparison of the two trials. However,
it is interesting to note that the gilts fed in the dirt lots were generally
much less efficient in feed conversion (3.4 for barrows and 4.0 for gilts).
Granting that the gilts were somewhat heavier initially and also finished at a
heavier average weight, both of which would not favor feed conversion, this
difference seems unusually great. This is particularly so when we realize that
gilts normally convert feed somewhat more efficiently than barrows. Possible
explanations include, adverse effects of cold wet weather, more exercising and
greater exposure to internal parasite infection.
In both trials the copper supplementation increased the level of feed
intake some but exerted no marked influence on feed conversion. The rate of gain
was also slightly greater in the copper supplemented groups. However these;differ-
ences were not statistically significant.
A total of eighty-four growing-finishing pigs were utilized to test the
supplementary value of 125 ppm copper fed as copper sulfate (CuS04). The copper
supplemented pigs consumed more feed than tne control pigs, converted feed to
gain at the same level of efficiency as control pigs and gained slightly faster
but not significantly faster than control pigs.
1. Vallace, H. D. 1967. High Level Copper in Swine Feeding. A review of
research in the United States. Published by International Copper Research
Assoc., Inc. New York, New York.
Table 1. Basal Feed Mlixture
Ground yellow corn 78.75
Soybean oilmeal (50% protein) 18.00
Defluorinated phosphate 2.50
Iodized salt 0.50
Trace minerals1 0.15
Vitamin supplement 0.10
I/ Contained 11% calcium, 10% manganese, 10%
iron, 10% zinc, 1% copper, 0.3% iodine
and 0.1% cobalt.
2/ Contained 6,000 mg. riboflavin, 20,000 mg.
niacin, 12,000 mg. pantothenic acid,
80,000 mg. choline chloride, 10,000 mcg.
vitamin B12, 2,500,000 I. U. of vitamin
A and 400,000 I. C. U. of vitamin D3
Table 2. Influence of High Level Copper Supplementation On
Feedlot Performance of Growing-Finishing Swine
TRIAL I TRIAL 2
CASTRATE IALES FEMALES
FED IN CONCRETE CONFINEMlENT FED IN SHALL DIRT LOTS
TREATMENT CONTROL SUPPLEMENTED1/ CONTROL SUPPLEMENTED-1
Number of pigs
Av. initial wt., lb.
Av. final wt., lb.
Av. daily feed intake, lb. 6.24 6.40 7.04 7.34
Av. daily gain, lb. 1.84 1.86 1.76 1.83
Feed required per unit gain 3.41 3.44 4.00 4.01
Av. number of days on test 87.8 88.5 92.0 92.0
1/ Copper was fed as copper sulfate (CuSO4) at a level to contribute 125 ppm
of copper to the diet.
2/ One pig was stolen from this lot on Nov. 10, 1969. Feed and average initial
lot weights were adjusted so that the data presented represent performance
of the remaining twenty-three pigs.