SWINE 597 



temperament. Bacon hogs stand in marked contrast in that the typi- 

 cal representatives have greater relative length, medium depth and 

 breadth, similar smoothness but more trimness, long legs; small, trim, 

 tapering hams; very neat, tidy jowls; very light and trim shoulders; 

 exceptionally firm finish (with slight external fat layers) and active 

 temperament. 



. The general or dual purpose breeds are a combinaton of the bacon 

 and lard types, emphasis being placed upon the development of suitable 

 market hams, bacon, ribs and loin, as well as the tendency to produce 

 marketable animals suitable for lard. 



The most typical lard type representatives are the Poland Chinas, 

 black with white markings or spotted black, white and sandy; the Duroc 

 Jerseys, entirely of a cherry red; and the Chester Whites, wholly white. 

 These three breeds are especially popular in the corn belt, and deservedly 

 so. Other lard type breeds are the Mulefoots, black, sometimes with white 

 markings; the Victorias, white; the Cheshires, white; the Suffolks, white; 

 the small Yorkshires, white; the Essex, black; and the Sapphires, blue 

 (sometimes white markings). 



The typical bacon type representatives are the large Yorkshires, 

 white; and the Tarn worths, red; both being especially prominent in Can- 

 ada and the northern United States. 



The dual purpose representatives are the Berkshires, black with white 

 markings; the Hampshires, black with white belt; and the middle white or 

 middle Yorkshires, white but little known in this country. 



Of the breeds mentioned, seven are white, six all black or black with 

 either white or sandy markings, two red and one blue. The most widely 

 distributed pigs in the Canadian country are white, whereas in the corn 

 belt and southern districts they are either black or red. This probably 

 represents climatic adaptation. 



Grading Up the Herd. — An ordinary farm herd composed of native 

 individuals may be advantageously graded up by using successive pure- 

 bred sires of the same breed. The first-cross animals are especially vigorous 

 for market as well as for breeding purposes; they gain very rapidly and 

 economically, and likewise make very good mothers. 



In a grading-up program, assuming that a Duroc Jersey is used for the 

 first cross and the offspring of the first cross are again bred to Duroc 

 Jersey sires, it is surprising how quickly the offspring approach the Duroc 

 types. In a few years, providing gilts only are kept each year for breeding, 

 a typical Duroc Jersey herd, resembling closely the typical pure breed, 

 will be a reality. The same grading-up process may be followed with any 

 pure breed. This is an excellent practice and one to be followed with 

 profit in the production of a uniform, dependable market type. 



The crossing of breeds already crossed is to be discouraged, largely 

 because of the heterogeneous individuals which result, these being of 

 various types, sizes, colors and so on; this dissimilarity of offspring being 



