Excerpt from Swine Breeding Research at the Regional Swine Breeding LaboratoryFor the purpose of discovering, developing, and testing procedures of breeding that will result in improvement of swine, the Regional Swine Breeding Laboratory was established in 1937 with headquarters at Ames, Iowa. Investigations are coordinated and carried on co operatively between the United States Department of Agriculture and the agricultural experiment stations of Illinois, Indiana, Iowa, Kan sas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio. Oklahoma, South Dakota, and Wisconsin.The experiments initiated relate mainly to systems of breeding. Inbred lines are being formed within pure breeds and from cross bred foundations. The 40 lines already formed range from about 10 to 70 percent in inbreeding.In general there has been a slight decrease in fertility, vitality, and rate of growth as inbreeding has advanced. In the better lines, how ever, the decline noted has not been enough to be serious. In some lines these traits have remained at the level shown by the foundation stock, and other traits - economy of gain, for example - have im proved. In genetically good stock the rate of inbreeding can be increased at least 5 to 10 times as fast as that being practiced by breeders of the pure breeds without serious loss of individual merit.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.