Animal Husbandry and Nutrition Florida Agricultural
Mimeograph Series No. 61-6 Experiment Station
January, 1961 Gainesville, Florida
THE EFFECT OF PRE-SLAUGHTER FEEDING OF SUCROSE TO
SWINE ON SLAUGHTER, CARCASS AND QUALITY CHARACTERISTICS1/
A. Z. Palmer, H. D. Wallace and J. W. Carpenter'/
The feeding of slaughter hogs over week-ends and holid3as is costly
to the commercial slaughterer; labor and feed costs, more frequently than
not, exceed returns for the feeding practice in terms of salable meat and
by-products. In practice hold-over slaughter hogs are fed only shelled
corn which amounts to a change in diet for some animals and results in
decreased consumption. Considering this fact, along with the condition
that all animals are in strange surroundings and mixed with strange hogs,
slaughter animals do well to maintain weight over a 48 to 72 hour holding
The situation, as previously described, brings up the question of
whether or not the use of a more palatable ration would increase consumption
to a point detectable by increased carcass and liver weights and improved
The use of sugar in young pig rations has been shown to enhance
palatability (McMillanet al., 1954; Lewis et al., 1955; Diaz et al.,
1956). Rations containing 10% to 40% "C" sugar, a low grade sugar in
polarization and purity, have been successfully used in creep rations
(Combs et al., 1956) and in growing-finishing rations (Combs et al., 1959).
Feeding sugar has been shown to increase dressing percent (Wilcox et al.,
1953; Combs et al., 1959) and liver weight (Gibbons and Rose, 1950;
Wilcox et al., 1953; Greenwood et al., 1953; Combs et al., 1959). Liver
desirability as determined by taste test, has been reported improved by
(Wilcox et al., 1953; Greenwood et al., 1953; Combs et al., 1959).
The feeding trials reported herein were designed to study the effects
of pre-slaughter feeding of sucrose on feed consumption, dressing percent,
liver percent, cooler shrink, yield of ham, loin, picnic and butt, liver
and loin chop palatability and loin eye area.
I/ The cooperation of Sunnyland Packing Co., Gainesville, Florida and the
assistance of Howard S. Povey, Meats Laboratory Manager, Mrs. Norma
Bowles and Richard Newman, Laboratory Assistant, Department of Animal
Husbandry and Nutrition, University of Florida, throughou ,f.this study
is acknowledged. /..--
2/ Palmer and Wallace, Associate Animal Husbandmen; and Cdrpenter, Assis-
tant Animal Husbandman, Department of Animal Husbandr "a.nd Nutri46n,
University of Florida, Gainesville, Florida.
Two trials were conducted in this study. In Trial I fifty-four
crossbred pigs of mixed breeding from the University herd were weighed
off a previous feeding experiment upon reaching slaughter weight and allotted
to the hold-over sugar feeding study according to previous treatment, weight,
sex and litter. Previous feeding treatments were as follows:
Lot I Ground corn ration from weaning to market weight.
Lot 2 Ground snapped corn ration from weaning to market weight.
Lot 3 Ground corn ration from weaning to 100 lb., ground snapped
corn ration from 100 Ib. to market weight.
Lot 4 Ground corn ration from weaning to 150 lb., ground snapped
corn ration from 150 Ib. to market weight.
Twenty-seven Trial I pigs were individually self-fed No. 2 shelled
yellow corn 48 hours prior to slaughter. The other 26 pigs were individ-
ually self-fed a ration consisting of 60% ground yellow corn and 40%
sucrose 48 hours prior to slaughter.
In Trial 2 fifty grade barrows and gilts were selected from the yards
of a local meat packing plant and divided according to weight and sex into
two groups for ad libitum feeding. One group was fed shelled corn 60 hours
prior to slaughter and the other group was fed the ration containing 60%
ground yellow corn and 40% sugar for the same period.
In both trials carcasses were dressed packer style; dressing percent
and liver percent were calculated on initial weight rather than the slaughter
weight obtained immediately before slaughter. This was done to minimize the
effect of "fill", as influenced by consumption during hold-over feeding,
on dressing and liver percent. Further, it was felt that resulting percent-
ages would be more useful in comparing feeding treatments in terms of gain
or loss in carcass and liver weight. Dressing percent was calculated by
Dressing percent = chilled carcass wt.
initial live weight
Liver percent was calculated by the formula:
Liver percent = hot liver wt. X 100
initial live wt.
Percent carcass shrink during a 24 hour chill at 340 F. was calculated by
Percent cooler shrink = chilled carcass wt.
hot carcass w00
hot carcass wt.
Trial 2 carcasses were not used in cutting studies; livers and chops
were not tested for palatability.
The carcasses of THial I were broken down by a standard cutting pro-
cedure (described by the Reciprocal Meat Conference). The combined percent
of the four lean cdts as well as individual percentages of ham, loin,
picnic and butt were calculated using the initial live weight of each animal
and the weights of the trimmed wholesale cuts.
Liver slices were prepared for taste test by cooking in a covered
petri dish for 20 minutes in a 3500 F. oven. Pork loin chops were
broiled to an internal temperature of 1800 F. and chilled to room tem-
perature; two half-inch cores were taken for Warner-Bratzler shear determin-
ations, The chops were tested for tenderness and juiciness and the liver
slices for tenderness and sweetness by a four-member panel; scores were
on a I to 9 hedonic scale with 5 being average and higher values being
more tender or sweeter in taste.
Loin eye area was determined by standard procedure (Kline and Hazel,
1955) on both loins of each Trial I carcass and averaged for the values
used in this study.
The data were analyzed by analysis of variance described by Snedecor
RESULTS AND DISCUSSION
Trial I and 2 data are presented in Tables I and 2, respectively.
In Trial I, a marked difference in feed consumption was found between
pre-slaughter feeding treatments (P<0.01). The pigs fed the ground corn-
sugar feed consumed an average of 13.2 Ibs. during the 48 hour period as
compared to 4.1 Ibs. of shelled corn consumed by the other group during
the same period. It Is interesting to note that previous treatments in-
fluenced consumption (P~:0.01) of both the shelled corn and the ground
corn-sugar feeds. Trial 2 consumption data confirm Trial I data; the ground
corn-sugar feed was more palatable than shelled corn as evidenced by greater
Pre-slaughter feeding in Trial I showed no effect on average back fat
thickness. Previous feeding treatment had a pronounced effect on back fat
Pigs fed the ground corn-sugar feed had larger livers than the pigs
fed shelled corn (PcO.OI) in Trial I; previous treatments influenced liver
effect on feed consumption.
Pre-slaughter feeding treatments used in both trials did not signifi-
cantly affect dressing percent. It is interesting to note, however, in
all comparisons that can be made such as previous treatment I vs. previous
treatment I in Trial I and barrows vs. barrows in Trial 2, animals fed the
ground corn-sugar feed averaged slightly higher dressing percentages.
Percent cooler shrink did not differ between pre-slaughter treat-
ments in either Trial I or Trial 2. In Trial I, the pH of chilled L. Dorsi
was not influenced by either pre-slaughter or previous feeding treatments;
tenderness and juiciness values on broiled loin chops as well as Warner-
Bratzler shear values were similar for all treatments.
In Trial I, livers from the pigs fed ground corn and sugar were more
tender (P<0.01) and sweeter (P<'0.01) than livers from pigs fed shelled corn.
In Trial I, the combined yield of the four lean cuts, ham, loin, picnic
and butt, was greater from pigs fed the ground corn-sugar feed than from
pigs fed shelled corn (PO.05). Previous feeding treatments had a highly
significant effect on the combined yield of four lean cuts (P<0.01) -
the fatter carcasses yielding the lower percentages.
Loin eye area was not influenced by pre-slaughter treatment. Pigs
fed ground snapped corn in previous treatments averaged larger loin eyes
than pigs fed ground corn meal. However, differences were not significant.
A study involving a total of 103 finished market hogs was conducted
to determine the influence of a preslaughter feeding treatment on carcass
yields. The feeding of a ration consisting of 60% ground corn and 40%
sucrose was compared to the usual procedure of feeding straight shelled
corn. The sugar ration increased feed consumption, liver weights, yield of
the four lean cuts and improved tenderness and sweetness of the livers.
Combs, G. E., H. D. Wallace, J. W. Carpenter, A. Z. Palmer and 1. H.
Alsmever. 1959. Feeding performance and carcass characte-istics
of growing-finishing swine fed "C" grade sugar. J. Animal Sci.
Vol. 18, No. 4, November, 1959.
Combs, G. E., C. E. Haines and H. D. Wallace. 1956. "C" sugar in the
creep ration of suckling pigs. Ani. Husb. and Nutr. Mimeo. Series
N. 55-15. Fla. Agr. Exp. Stat., Gainesville.
Diaz, F., V. C. Speer, G. C. Ashton, C. H. Liu and D. V. Catron. 1956.
Comparison of refined cane su:r, invert cane molasses and unre-
fined cane sugar in starter rations for early weaned pigs. J.
Animal Sci. 15:315.
Gibbons, N. E. and D. Rose. 1950. Effect of anti-mortem treatment of
pigs on the quality of wiltshire bacon. Canadian J. Res. 28:438.
Greenwood, D. A., E. B. Wilcox, H. Steffen, L. E. Harris and L. Shupe.
1953. Influence on animal carcass of feeding sucrose. Agr. and
Food Chem. 1:1112.
Kline, E. A. and L. N. Hazel. 1955. Loin area at tenth and last rib as
related to leanness of pork carcasses. J. Animal Sci. 14:659.
Lewis, C. J., D. V. Catron, G. E. Combs, G. C. Ashton and C. C. Culbertson.
1955. Sugar in pig starters. J. Animal Sci. 14:1103.
McMillan, F. A. and H. D. Wallace. 1954. Palatability studies on creep
feed formulations for suckling pigs. J. Animal Sci. 13:39.
Reciprocal Meat Conference, Proceedings of the Fourth Annual. 1951.
Snedecor, G. W. 1956. Statistical Methods (5th Ed.) The Iowa State
College Press, Ames, Iowa.
Wilcox, E. B., M. B. Merkly, L. S. Galloway, D. A. Greenwood, W. Binns,
J. A. Bennett and L. E. Haines. 1953. The effect of feeding sucrose
to beef cattle and swine on the dressing percentage and quality of
meat. J. Animal Sci. 12:24.
TABLE I. A COMPARISON OF THE EFFECTS OF PRE-SLAUGHTER FEEDING OF SHELLED CORN AND GROUND CORN PLUS SUCROSE. TRIAL I.
Fed Shelled Corn Fed Gr. Corn 60% & Sugar 40% Sig. of Differences
Item Previous Treatment Over- Previous Treatment Over- Slaughter Previous
all all Treatments Treatments
S 2 3 4 Av. I 2 3 4 Av.
Av. Initial wt., I
Av. Final wt., Ibs
Av. Feed Cons., lb!
Av. Backfat, inc.
Av. Liver, % a/
Av. Dressing % a/
Av. Cooler Shrink
Av. pH L. Dorsi
W. B. Shear, av.
Four Lean Cuts a/
Combined Four Lean
Loin Eye Area, av.
4.84 5.02 5.42 4.81 5.03
4.75 5.30 5.41 5.02 5.14
35.02 36.23 36.78 36.37 36.14
3.77 3.73 3.84 3.78 3.78
5.71 5.86 6.33 6.27 6.04
5.89 5.67 6.21 5.92 5.91
4.78 14.35 14.21 14.31
2.57 11.54 11.70 11.69
6.77 6.27 6.34 6.45
4.99 4.55 4.80 4.71
S9.11 36.71 37.06 37.12
4.18 4.02 4.17 4.01
A COMPARISON OF THE EFFECTS OF PRE-SLAUGHTER FEEDING
OF SHELLED CORN AND GROUND CORN PLUS SUCROSE. TRIAL 2i
a/ Percentages based on initial
Fed Shelled Corn Fed Ground Corn 60%
Item __and Sugar 40%
011 Combined O0 Combined
No. Animals 14 II 25 14 II 25
Av. Initial wt., Ibs. 202.4 185.3 194.9 201.9 185.8 194.8
Av. Final wt., Ibs. 199.6 187.3 194.2 203.1 190.6 197.6
Av. Feed Consumption,
Ibs. -- -- 9.52 -- 13.44
Av. Liver, % a/ 2.10 2.28 2.17 2.33 2.70 2.49
Av. Dressing, % a/ 68.77 68.13 68.49 69.76 69.86 69.80
Av. Cooler Shrink, % 2.53 2.79 2.64 2.35 2.57 2.45