MANUAL OF CATTLE-FEEDING. 201 



smaller amount of lijBmoglobin contained in tlieir blood, 

 while the differences observed between different breeds in 

 this respect may be partly owing to the same cause. 



In cases of phosphorus-poisoning, an enormous formation 

 of fat is observed, amounting sometimes to fatty degener- 

 ation of the tissues. Phosphorus acts as a poison by 

 depriving the blood of oxygen, and as one of the effects of 

 this we see an abnormal formation of fat, due apparently 

 to the poverty of the blood as regards oxygen. 



The amount of oxygen taken up by the blood must also 

 be influenced by the amount of hmg surface, the rapidity 

 of circulation and respiration, etc. ; but while it is a popular 

 and perhaps well-founded belief that the differences ob- 

 served between different animals as regards ease of fatten- 

 ing, are largely due to differences in build, especially in 

 the size of the lungs, there has been as yet no scientific 

 study of this interesting question. 

 9* 



