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OCR for page 143
T. J. CUNHA
Eliminating Excess Fat
in Meat Animals
The United States can continue for decades to produce all the animal
products needed. But the task requires a change in production programs
and elimination of excess fat in meat animals.
The United States is producing beef and pork that are fatter than the
consumer wants them to be. When this country had a grain surplus,
many farmers preferred to market their grain through animals the
profit was greater that way. It did not matter if the animals had a certain
amount of excess fat. It could be trimmed off by the packer, the retailer,
and the consumer. Now a turnaround has occurred. Grain is scarce and
high priced, and grain exports are being used to fight world hunger and
to help the United States with balance-of-trade problems. Thus, wasting
grain in feeding and overfinishing cattle and swine should be discon-
tinued. A certain amount of fat is needed for carcass quality and eating
quality. But excess fat is costly; gains become more expensive as an
animal becomes fatter.
CAT T L E
It is estimated that about 20% of the excess fat is trimmed from Choice
beef carcasses. This waste could be reduced if more cattle reached the
Choice grade with no more than 0.5 in. of fat over the rib-eye area.
Some cattle reach the Choice grade with only 0.2-0.3 in. of fat. In-
creasing emphasis should be placed on the development of breeding,
feeding, and management programs that would gradually reduce the
amount of excess, trimmable fat in beef carcasses.
143
OCR for page 144
144
T. J. CUNHA
Table 1 shows what occurred in three gain periods of a finishing trial
with 475-lb British-breed cattle and their crosses at the University of
Florida. About three times as much separable fat as separable lean tissue
was being deposited in the gain from the 126th to 168th day in the feed-
lot. The gain for that period consisted of about twice as-much fat as
for the first 84 days in the feedlot. Moreover, the separable lean tissue
deposited in the gain during the last period was only 39.5~o of the
amount deposited during the first period. All this information indi-
cates that it is important to know when the optimal slaughter weight
occurs with cattle of different breeding. There is a period when con-
siderably more fat than lean tissue is being deposited. The animal should
be slaughtered before too much fat is deposited-fat that later has to be
trimmed off.
There are many indications that increased emphasis will be placed on
solving the waste-fat problem in cattle in the future. The following
pressures can be expected:
· Because of increased feed costs, an effort will be made to produce
cattle that have gainability, gradeability, and curability- and a mini-
mum of excess fat.
· Consumers will demand leaner beef at moderate prices. Some major
food retail chains have already switched to promoting Good beef be-
cause of the leanness.
· Increased movement to "boxed" beef and away from carcass beef
will cause packers to place more emphasis on curability, since they will
be doing more of the trimming. No longer will ~ thick layer of fat be
needed to prevent surface drying; a primary package will protect the
meat. This centralization of carcass-breaking procedures will reduce
labor and shipping costs and will promote the production of trim, heavy-
muscled cattle.
TABLE 1 Results of Three Gain Periods of a Finishing Trial with
British-Breed Cattle and Their Crossest
Carcass Gain (% )
Carcass Gain Separable Lean Separable Fat
Days in Feedlot during Period (lb) Tissue Tissue
1-84 129.7 57.7 35.4
84-126 86.3 36.9 54.0
126-168 60.7 22.7 71.6
a SOURCE: A. Z. Palmer, J. S. Scott, D. E. Franke, and J. F. Hentges, University of Florida.
AH mimeo series 71-3, May 1971.
OCR for page 145
Eliminating Excess Fat in Meat Animals
145
· Sociological pressure to use less grain in animal feeding and more
for human consumption will be felt. This pressure is real, but it should
be pointed out that about 75% of the feed used during the lifetime of a
finished steer consists of forage, by-product feeds, and other ration
items not consumed by people. Less grain is used with the beef cow,
which consumes 95% of its feed as forage. Moreover, cattle and sheep
graze about half the land area of the United States (about 1 billion
acres) land that is not being used for other purposes at this time.
Dr. Jim Elam of Santa Ynez, California, reported in the November 1974
issue of Calf News that if cattle were fed only 90-100 days to weights
of 1,070 lb (instead of heavier weights), 1 lb of salable beef (480 lb of
salable beef from a 1,070-lb animal) would require only 1.86 lb of
grain, the same amount required to produce a pound of salable chicken.
In the future, less grain will be fed to cattle. There are several
reasons:
· Cattle will be bred for producing less excess fat and for reaching
the Choice grade with less outside fat.
· More forage will be fed prior to feedlot finishing.
· More by-product and other energy feeds not used for human con-
sumption will be fed.
· The feedlot finishing period will be shortened.
· More attention will be paid to marketing cattle nearer the "optimal
slaughter point" before they start putting on excess fat.
S WI N E
In the United States the average pig requires 3.3-3.5 lb of feed per
pound of gain from weaning to market weight. But in 1971 a top per-
forming pig in a U.S. Swine Evaluation Center required only 2.24 lb of
feed per pound of gain a reduction of about one third. This makes
clear that good meat-type pigs can be produced on considerably less
than the average amount of feed.
Close to 90% of the barrows and gilts marketed in the United States
have more separable fat than separable lean in their carcasses. There-
fore, swine producers should put greater emphasis on raising meat-type
pigs. Since carcass characteristics are highly heritable, they can be im-
proved quickly by selection programs. The average estimates of hentabil-
ity are as follows: carcass length, 56%; carcass backfat thickness,
38%; yield of lean cuts, 29%; and length of hind leg, 40%.
Excess fat in swine can be reduced with breeding, feeding, and man
OCR for page 146
146
T. J. CUNHA
agement programs. Also, producers should use more by-product feeds
and other feeds (including new feeds) and grains not consumed by
people in the future.
REPRODUCTION IN MEAT-TYPE ANIMALS
A word of caution is needed concerning programs to develop meat-type
pigs and steers. Some pigs have been bred to the point where they are
too heavy in the ham and loin areas and too light in the front part of
the body. Because of inadequate capacity for the lungs, heart, and
digestive tract, some of these animals experience difficulty in the latter
part of the growth period and during reproduction. Therefore, as breed-
ing programs are developed for producing meat-type pigs, attention
must be given to ensuring that the animals can function properly
throughout growth and during reproduction. The same is true for beef
cattle. Moreover, the animals should not be susceptible to abnormal
physiological conditions. Pale, soft, exudative pork, pork stress syn-
drome, and double muscling in cattle may have been brought about by
selection for meat-type animals.
Selection for meat-type animals must not be at the expense of meat
quality. Acceptable quality levels must be maintained. Experience has
indicated that problems in carcass quality become more frequent with
extremely heavy muscled, trim animals. In the future, the economical
animal will be one that has a correct combination of gainability, cut-
ability, and palatability, without excess fat.
CONCLUDING REMARKS
Animal products with more unsaturated fat can be produced. But before
this is done, the benefit to human health must be clearly shown. More-
over, we must determine whether consumers will accept animal products
that have more unsaturated fat than those now available. I am confident
that U.S. scientists will develop feeding, breeding, and management
programs that will ensure the production, for decades to come, of all
the animal products needed.
Representative terms from entire chapter:
animal products
