ILLUSTRATIONS 



PIGUKE PAGK 



1. Composition of steers from 100 to 1200 pounds. (T. L. Haecker, 



Minnesota Experiment Station) 29 



2. Porterhouse steak from a prime steer. Note the "marbling." 



(Illinois Experiment Station) 32 



3. Digestive tract of man — schematic. (Paton, Veterinary 



Physiology, Chicago Medical Book Company) . . .35 



4. Stomach of the horse. (Sisson, Veterinary Anatomy, W. B. 



Saunders Publishing Company) 36 



5. Csecum of the horse. (Smith, Manual of Veterinary Physiology, 



Bailliere, Tindall and Cox) 37 



6. Head of cow, showing some of the salivary glands. (Sisson, 



Veterinary Anatomy, W. B. Saunders Publishing Company) 38 



7. Digestive tract of the horse. (United States Department of 



Agriculture) 39 



8. Stomach of a sheep. (United States Department of Agriculture) 44 



9. Cross-section of mucous membrane of the small intestine. 



(Jordan, Principles of Human Nutrition, The Macmillan 

 Company) 48 



10. Longitudinal section of a villus. (Jordan, Principles of Human 



Nutrition, The Macmillan Company) 49 



11. Loop of small intestine of the horse during active absorption. 



(Smith, Manual of Veterinary Physiology, Bailliere, Tin- 

 dall and Cox) 50 



12. Digestion harness on a pig (Illinois Experiment Station) . 57 



13. These pigs were fed a ration deficient in phosphorus. (Wis- 



consin Experiment Station) 78 



14. These pigs were fed the same ration as those in Figure 13, with 



the addition of phosphorus in the form of calcium phos- 

 phate. (Wisconsin Experiment Station) .... 79 



15. Abnormal bones from hogs whose rations were low in calcium 



(corn alone, and corn and soybeans). (Ohio Experiment 

 Station) . 80 



