16 



to answer an apparently simple question. Great care is necessary, therefore, in 

 interpreting the results of live-stock experiments, and it will not do to draw 

 general conclusions where only a limited amount of work has been done. 



Influence of Feed upon the Body of the Pig. 



In his excellent book, " Feeds and Feeding," Professor Henry gives an 

 account of work done along this line by Sanborn at the Missouri Agricultural 

 College, Henry at the Wisconsin Experimental Station, Shelton in Kansas, Duggar 

 in Alabama, and Fortier in France. 



Corn, which is the standard hog feed of the United States, is a feed rich is 

 carbohydrates, or fat-forming constituents, but rather low in protein, or muscle- 

 forming constituents. It is also low in ash, or bone-forming material. The 

 question arose, therefore, whether a feed such as corn would not have a tendency 

 to produce more fat in the body of a hog than would feeds which contain, a higher 

 percentage of protein and ash. Without going into details, it may be said that 

 corn was fed in opposition to mixtures containing such feeds as dried blood, wheat 

 middlings, peas, skim-milk, bran, and cow-peas, which are feeds much richer than 

 corn in protein. 



Results. — The methods employed in the investigation varied somewhat, but 

 tlie general results were as follows: 



1. The pigs fed the protein-rich ration generally dressed a somewhat lower 

 percentage of their live weight than those fed the corn ration. 



2. In nearly every case, the pigs fed the protein-rich ration had the largest 

 quantity of blood, and in every case they had heavier livers than the others. Their 

 kidneys were also heavier, as a rule, though there were some exceptions. 



3. In the Wisconsin and Kansas experiments, the tenderloin muscles were 

 removed and weighed, and in both cases these were heavier in the case of the 

 protein-fed pigs. The tenderloin muscle is an indication of the amount of lean 

 throughout the. carcass, and hence it was demonstrated that the carcasses of the 

 protein-fed pigs contained more lean than the others. 



4. As a rule, the corn-fed pigs gave more leaf-lard than the others. 



5. At the Wisconsin and Kansas stations, the breaking strength of the thigh- 

 bones was tested by a machine designed for such purposes, and in every case the 

 bones from the pigs fjd the mixed ration proved stronger than those of the corn- 

 fed pigs, the difference being as high as 32 per cent, in one trial. 



Limitations.— Though the experiments described demonstrate very clearlj 

 that it is possible to modify the carcass of the pig by a judicious selection of feeds, 

 we must not assume that lean or fat can be developed to any extent which the 

 feeder may desire. Nature has set a limit in this connection, and what may be 

 accomplished by the feeder in the way of developing lean meat cannot go beyond a 

 certain point. The theory that any breed of hogs can be fed in such a way as to 

 produce choice bacon for the English market is not borne out by these or any 

 other experiments, nor by the experience of practical breeders who really under- 

 stand the demands of the market. 



A peculiar featur-^, of swine is their tendency to develop fat. If the very 

 best specimens of the bacon type are fed largely upon corn, they quickly assume 

 the fat or lard type, and in one or two generations of such treatment the tendency 

 to become shorter in side and thicker in body becomes so firmly fixed that it is very 



