Cutting Yields of Hogs an Index of Fatness

Fatness is one of the major factors affecting the market value of hogs and hog carcasses. The preference of consumers for the leaner cuts of meat and the competition of vegetable oils have resulted in comparatively low prices for lard, fat cuts, and very fat hogs. Breeders and research workers are consequently endeavoring to select and establish types and strains of hogs that will produce the most desirable proportion of lean to fat. To do this they are conducting breeding trials, performance tests, registers of merit, and hog-carcass contests. A basic problem in this work is to determine as accurately as possible the comparative fatness of the carcasses produced. Comparisons of fatness, on the market, are made by observing or judging the appearance of the carcass. This method is neither accurate nor permanent enough for the definite comparisons needed by constructive breeders or research workers. The most accurate means of determining the fatness of a hog carcass is obviously a chemical analysis of the carcass. The time, expense, and quantity of meat involved in this method, however, often make it impracticable. Chemical analysis also entails the loss of the pork for other experiments. It would be desirable to have more simple measurements, if their relation to the fatness of the carcass could be established. Three types of measurements seem particularly adapted for determining the actual fatness of a pork carcass. In the order of probable accuracy they are as follows: (1) The chemical analysis of some single, representative cut; (2) the weight of particularly fat or lean cuts in relation to the weight of the entire carcass; and (3) measurements of parts of the carcass, especially the fat portions, such as thickness of the fat on the ham, shoulder, and back. The second type of measurement—that of estimating the fatness of an animal from the proportions of the fat or lean cuts in the carcass— was selected as the basis for the study reported in this paper. The existence of a relationship between these weights is indicated by the work of other investigators as well as by that of the writers. Moreover, the procedure was more practicable than an analysis of a selected cut and was thought to be more accurate than measurements of the fat layers of hogs of various weights. This paper also includes a