Progress in Hog Production

by JOHN H. ZELLER

FARMERS keep asking three questions about hogs : What is the best type and breed? How do parents pass their distinct features on to their offspring? How can we improve production? Another question was added a few years ago when it became plain that the usual kind of pig had too much lard, which, because of the growing competition of fats of plant origin, depressed the price of live hogs. Swine breeders and workers in agricultural experiment stations agreed that if the hog business were to stay profitable, they would have to develop a leaner animal—one that would grow well on the available feed and under American production methods.

One sign that the questions are being answered is the record made during the war. In 1943, for example, more than 121 million pigs were raised, more than ever before, and 66.4 percent above the average in the decade before that.

Research before the war indicated that an intermediate type suited the needs of the American producer and consumer better than extremes, particularly in the Corn Belt—a hog that could be finished at 200 to 240 pounds or, on farms with plenty of feed, at 300 pounds or more. This kind promises to be adaptable to a wide range of production and marketing conditions.

To develop this meat type the Department, in cooperation with the Iowa Agricultural Experiment Station, imported 23 head of Landrace hogs from Denmark in 1934 for use in experiments in breeding and feeding. The Danish Landrace had been bred under testing-station methods for many years, and was producing carcasses that were favored by the London bacon market.

Some of the Landrace were crossed with domestic breeds to determine whether we could improve the meat of domestic stock and perhaps reduce lard yields. Several strains were started from the various crosses. From them, strains similar in type to the Landrace are being produced. They are a little longer of body and shorter of leg than the domestic breeds that were used in the crosses, and the carcasses compare favorably with those of the domestic breeds.

We believe that some of the strains may ultimately aid in improving domestic stock through systematic crossing. Cross-breeding has been practiced generally by many hog producers for years, because of the hybrid vigor usually obtained. These and other studies should ultimately point a way for obtaining the maximum in hybrid vigor from systematic crossing and perhaps eventually get better carcasses than are now had.

At the Regional Swine Breeding Laboratory at Ames, Iowa, an institution established in 1937 by agricultural experiment stations in the Corn Belt and the Department, experiments are in progress to explore possibilities for using inbred lines to improve the seed-stock value of pure breeds, and improve the performance and the carcasses of hogs produced for market. Methods of selection also are being investigated. Progress is being made. Some day inbred lines may be used not only to improve pure breeds, but also, when used systematically, may yield more pork per litter than the established practices.

The methods being tested in the various experiments have demonstrated that inbred lines can be produced within any of the pure breeds, and that the very best of the lines may have a place in future hog production. Likewise, useful lines can be formed from crosses of breeds. There is some evidence that lines from crossbred foundations may give more hybrid vigor in crosses than lines formed within breeds.

Today, swine breeders emphasize performance records as a means of improving the herd. The usefulness of such records in the dairy and poultry industries has been demonstrated by years of testing and proving superior stock.

Performance records for sows require earmarking of pigs and weights of pigs at weaning time. More thought is being given to final selection of boars and gilts for the breeding herd and how they can be used to increase feedlot efficiency and yield high quality carcasses.