Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to the feeding of domestic
animals, and particularly to a growth enhancing supplement for
the feed rations of pigs, and to a method of administering the
supplement to the pigs.
The growth of domestic animals intended for slaughter
has been enhanced by feed supplements including antibiotics
and chemotherapeutic agents common to human and vekerinary
medicine, but such supplements have recently been found to be
potentially injurious to humans consuming the meat of the ani-
mals. Other growth promoting agents which have antimicrobial
effects in animals only such as Nitrovin 11,5-bis-(5-nitro-2- `
furyl)-l,4-pentadiene-3-one-amidinehydrazone hydrochloride]
and Carbado [methyl-3-(2-quinoxalinylmethylene)-carbazate-
Nl,N4-dioxide] have been proposed as substitutes for anti-
microbial agents also effective in humans, but are of li~it-
ed effect, and their safety for human consumption when present
in the meat of the treated animals has not yet been fully
established.
It is a common feature of the feed supplements ment-
ioned above that they control microorganisms in the ~igest-
ive tract of the animals and thereby make more nutrients avail-
able for conversion to animal tissue. They also prevent in-
testinal infections and thereby promote the growth of the
anlmals .
It has now been found that cupric methionate (the
copper salt of methionine which is practically insoluble in
water) enhances the growth of domestic animals, particularly
pigs, and improves the rate at which basic feed rations con-
taining carbohydrates, protein, ~d fat are converted to body
tissue of the animals when administered orally in daily
l Q~
- 1 - .,.
`, `
1Q68536
average amounts of S to 60 mg per kg of body weight over peri- -
ods of several weeks. The cupric methionate is most conveni-
ently mixed with the basic feed rations in amounts of 250
to 900 ppm, best results being usually achieved with admixtures
of 400 - 700 ppm. The improvement in the rate of conversion of
the feed to body tissue of pigs is improved by approximately
15%, and the rate of weight increase is enhanced b~ a similar
amount. Even greater improvement is achieved in very young
pigs which consume more feed per kg of body weight than adult
hogs.
Cupric methionate has no known or foreseeable side ef- -
fects on humans consuming the meat of animals receiving the
feed supplement. Its components, copper and methionine, are
normal ingredients of nutrients for human use as well as of
animal feed. It is known that oral doses of 540 mg cupric meth-
ionate per kg of body weight do not produce toxic effects
in pigs nor are such effects observed after intramuscular in-
jection of 100 mg/kg [Chem. Abstracts 58 (1963) 13031c]. The
amount of copper in the livers of swine fed rations supple-
mented with cupric methionate is well within normal limits and
not significantly different from that of swine livers produced
in the absence of cupric methionate.
Quite surprisingly, cupric methionate is superior in
its growth enhancing effects to equivalent mixtures of copper
sulfate and methionine, and the reason for this difference
is not understood at this time. While cupric methionate is a
known antihelminthic for swine [Tamasaki, Jap. J. Vet. Sci.
24 (5) 309-313; 24 (6) 359/365; Chem. Abstracts 61 (1964)
6231h], there is no connection between the known therapeutic
effect and the newly discovered growth promoting effect which
53:6 `
is observed in pLgs free from infection by intestinal worms.
Cupric methionate has no known antimicrobial effects, but ani-
mals receiving cupric methionate as a feed supplement gener-
ally are in better physical condition than animals not receiv-
ing the supplement, and are thought to be naturally more re-
sistant to disease. However, cupric methionate is entirely
compatible with antimicrobial agents effective in controlling
swine disease,and may be employed jointly with antibiotics and
chemotherapeutic agents.
For an equal weight gain, pigs receiving supplemental
doses of cupric methionate consume less basic feed which sup-
plies necessary amounts of carbohydrate, protein, fat, and
trace minerals,and the savings amount on an average to 15% of
basic feed weight.
Unexpectedly, the proportion of unsaturated fatty acids
in the fatback of hogs fed rations supplemented with cupric
methionate is higher than in hogs fattened on otherwise ident-
ical rations without cupric methionate. While this effect is
of obvious value, it cannot be explained at this time.
Cupric methionate, when fed to growing pigs in effect-
ive amounts, produces superior weight gain in the same time
and also per unit weight of basic feed consumed as compared
to the best known growth enhancing agents which are antimi-
crobial antibiotics or chemotherapeutic agents when such anti-
biotics or agents are administered orally to the pigs in op-
timum amounts.
The following Examples are further illustrative of this
invention. All percentage values are by weight unless stated
otherwise.
EXAMPLE 1
A herd of young pigs was divided into four matched
536
groups of 13 animals averaging 20 kg each. The animals were
provided with basic, commercial, pelletized feed of composit-
ion A listed in Table 1 for six weeks, and thereafter with feed
of composition B for two more weeks. Each metric ton of feed -~
was intimately mixed with 2 kg of a mineral supplement at a
rate to fortify 1000 kg of the basic feed composition with
100 g Fe, 40 g Mn, 100 g Zn, 0.2 g Se, 0.8 g I, and 0.1 g Co.
The average weight of the animals in each group was determined
after 2, 4, and 6 weeks. Thereafter, the three pigs of lowest
weight were removed from each group, and the average weight
of the ten remaining pigs was determined again after 6 weeks
and ultimately after 8 weeks.
The rations of Group I serving as the control group
were further fortified with 10 ppm Cu in the form of 28.5 g
CuSO4.H2O per 1000 kg feed, Group II received 100 ppm Cu as
the sulfate, Group III received 100 ppm Cu as 566 g cupric
methionate per 1000 kg, and Group IV 150 ppm Cu in the form
of 850 g cupric methionate per 1000 kg basic feed. The me-
thionine content of 850 g cupric methionate is 700 g, and Groups
I and II received this amount of methionine, Group III being
given 234 g methionine per 1000 kg of basic feed to supplement
the methionine content of 566 g inthe copper methionate.
Table 2 lists the difference in percent between the
average weight gain of the pigs in Groups II, III, and IV as
compared to Group I, the control group, and also lists the
change in the rate of conversion of the rations supplied to
pig's weight again with reference to the control Group I as
100%.
Each group was permitted to consume a tot~l of 6,000 kg
basic feed. Groups III and IV grew significantly faster during
. . .
536
the first four weeks of the test, but showed only minor advant-
ages over the control group thereafter because their rations
were not increased in proportion to their higher weight over
the rations given to Groups I and II.
TABLE 1
Feed composition, percent A B
Wheat 16.73
Barley 42.05 47.23
Oats 5.09 5 Q3
Corn 9.91 9.85
Legume seeds - 9.95
Wheat bran 5.02 6.93
Molasses 1.19 2.94
Soybean flour (44% protein) 5.07 10.02
Vitamines 0.60 0.60
Salt 0.51 0.51
Calcium carbonate - 0.76
Dicalcium phosphate 1.48 1.03
Herring meal 10.10 5.00
Meat meal 2.08
Total, percent
Protein 19.70 16.92
Starch units 68.04 67.00
Fat~(raw) 3.01 2.90
Lysine 1.05 0.85
Methionine 0.62 0.53
Cysteine + methionine 0.93 0.81
TABLE 2
After Differ'l Wt. GainFeed
Weeks Group Conversion
I kg Gr.II Gr.III Gr.IV Gr.II Gr.III Gr.IV
0 20
2 27 +2.5 +16.2 +13.0 +6.1 +20.0 +16.7
4 34 +18.0 +20.2 +18.4 +20.8
6 45.5 -1.8 + 8.0 + 3.2 -2.0 + 5.7 + 1.0
6 48
8 65 +0.6 + 5.0 +13.4 +0.5 + 6.0 +15.0
EXAMPLE 2
A genetically homogeneous herd of 54 young pigs was
divided into 6 matched groups A to F of 9 animals each. The
animals had an average starting weight of 6.3 kg each and had
-- 5 --
106~536
free access to pelletized, dry commercial rations similar
to Type A listed in Table 1 which were mixed with a mineral --
supplement providing all necessary trace elements other than
copper. Additionally, the six groups respectively received
in their feed 10 ppm Cu ~as CuSO4) (A), 100 ppm Cu (as cop-
per sulfate) (B), 566 ppm cupric methionate (C), 850 ppm
cupric methionate (D), 10 ppm Cu (as CuSO4) and 700 ppm
methionine (E), and 100 ppm Cu(as CuSO4) and 700 mg methionine
(F) which were intimately mixed with the basic feed. The ex-
periment was performed three times, and Tables 3 and 4 list
the average weight gain in g/day and the weight gain in kg .
per kg consumed feed for Group (A) in each of the three runs
and an average of the three runs, also comparison values, in
percent, for the other five groups, based on the values for
Group A.
TABLE 3
Weight gain per day .
Run Group Percentage Difference
No. A,kg/day Gr. B Gr.C Gr.D Gr.E Gr.F
1 285 -10 +16 +12 + 6 + 6
2 268 + 5 +32 +14 -10 +11
3 230 + 8 +23 +20 -17 + 7
Av. + 1 +24 +15 - 7 + 8
TABLE 4
Weight gain per kg feed
Run Group Percentage Difference
No. A,kg/kg Gr.B Gr.C Gr.D Gr.E Gr.F
1 0.572 -13 - 3 - 7 -15 -7
2 0.514 + 6 +10 + 4 -11 0
3 0.439 +19 +22 +28 + 5 +8
Av. + 4 ~10 + 8 - 7 0
36
EXP~LE 3
Two matched groups of 10 pigs stabled in individual
stalls and weighing approximately 40 kg each were fed a basic
feed containing 16.9% crude protein including 14.0~ digestible
crude protein, 4.55% crude fiber, 66.8% starch units, 0.753%
lysine, 0.54% methionine + cysteine and the necessary trace
elements (Fe, Mn, Zn, Se, I, Cu, Co). One group additionally
received 100 ppm copper as cupric methionate while the other
group received 15 ppm zinc bacitracin and 30 ppm furazolidone.
The group receiving the cupric methionate grew in 52
days from an average weight of 41.5 kg to 88 kg for a daily
weight gain of 894 g while the other group grew from an average
weight of 42.5 kg in the same period to 85 kg, an average
daily weight gain of 817 g.
EXAMPL~ 4
Two matched groups of 12 pigs each were fattened for
62 days on basic rations containing 18.5 - 19.5% crude prote-
in, 4 - 6% crude fiber, a total of about 70~ nutrients, and
further, per kg, 16,000 international units (I.U.) vitamine
A, 2000 I.U. vitamine D3, and 10 I.U. vitamine E. A mineral
supplement containing the necessary trace elements was inti-
mately mixed with the basic feed at a rate of 2 kg per metric
ton.
One of the groups additionally received in its feed
556 ppm cupric methionate while the other group received 80
ppm furazolidone and 22 ppm tylosin.
The animals receiving the cupric methionate grew, on an
average, from a starting weight of 7.55 kg to 33.30 kg, gain-
ing 0.420 kg per day and consuming 50.85 kg feed, thereby con-
verting each kg of feed into 0.50Ç kg of weight gain. The
536
second group grew on an average from 7.40 kg to 31.30 kg or
0.390 kg per day after consuming 61.20 kg feed per animal,
thereby converting each kg of consumed feed into 0.390 kg of
added weight.
EXAMPLE 5
Three matched groups of 10 piglets each were raised on
conventional commercial feed containing the necessary trace
elements. The feed for the first group additionally contained -
100 ppm arsanilic acid and 100 ppm zinc bacitracin, the feed
of the second group contained 50 ppm Carbadox, and the feed
of the third group contained 100 ppm copper in the form of
566 ppm cupric methionate.
The first group grew from a combined weight of 75 kg
in 23 days to 212 kg consuming 214 kg of feed, thereby grow-
ing on an average 331 g per day and animal, and converting
each kg of feed into 0.640 g of animal tissue.
The second group grew in the same period from 75 kg to
198 kg on 195 kg of feed for a growth rate of 297 g per day
and animal, and a conversion of each kg of feed to 0.631 kg
of animal tissue.
The third group grew fxom 74 kg to 214 kg while consum-
ing 201 kg of feed. The average growth rate was 338 g per day
and animal, and feed was converted to animal tissue at a rate
of 0.697 kg per kg of feed, a rate significantly higher than
obtained by the conventional growth promoting agents.
EXAMPLE 6
~wo matched groups of young pigs were fattened from an
average weight of about 20 kg to an average weight of approx-
imately 50 kg on a basic feed containing 17% - 18% crude pro-
tein, 14.8% digestible crude protein, 67% - 68~ starch units,
~ 8 -
36
0.95% lysine, and 0.65% methionine + cysteine. The pelletized
feed also contained the necessary trace elements and was
freely accessible to the animals. One of the two groups ad-
ditionally received in its feed 566 ppm cupric methionate
while the other group received instead 40 ppm Carbadox.~
The daily avarage weight gain of the pigs receiving
cupric methionate was 752 g, while the pigs receiving Carbadox~
gained an average of 645 g per day.
EXAMPLE 7
After pigs fattened by the methods described in Example
1 had gained an average weight of 100 kg, they were slaughtered,
and the copper content of liver specimens from three pigs
taken at random from each group was determined.
The organic matter in each specimen weighing 2 g was
destroyed by boiling practically to dryness in a Kjeldahl
flask with 5 ml concentrated sulfuric acid and alternatively
with 5 ml concentrated nitric acid and hydrogen peroxide. The
residue was taken up in 2 - 3 ml concentrated sulfuric acid
and 20 - 30 ml water, and 1 ml of the solution so obtained was
placed in a measuring cell with 20 ml 3 N hydrochloric acid
and analyzed for copper content by polarography.
While the values of copper content so determined varied
between 6.7 and 26.5 ppm Cu based on fresh liver tissue con-
taining about 25% to 3~% solids, all values were within normal
limits t no correlation could be found between the amounts of
copper in the feed and in the liver tissue, nor could signific-
ant differences be detected between livers of animals that had
received copper in the form of copper sulfate and cupric me-
thionate respectively.
EX~MPLE 8
Groups of three pigs each were fattened by the methods
R~
_ g _
1068536
described in Example 1, Groups II, III, and IV, and an ad-
ditional group of three pigs received 12 ppm Nitrovin with -
their feed instead of the 100 ppm copper as sulfate, 566 ppm
cupric methionate, or 850 ppm cupric methionate. After the
animals were slaughtered, the inner layers of their fatbacks
were analyzed for linolic acid and linolenic acid. The amount
of linolenic acid was 0.6~ in all tested specimens, but lin-
olic acid ranged from 10.0% for pigs receiving 100 ppm Cu as
the sulfate through 10.3% for the Nitrovin fed animals to 11.7%
for 850 ppm cupric methionate in the feed, and 12.0% for 566 `~
ppm cupric methionate. The amount of total polyunsaturated ~-
acids in the fatback is thus increased by about one seventh
after fattening on feed enriched with cupric methionate as
compared to conventional supplements.
-- 10 --
