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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

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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.

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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

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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.