118 Qattle Problems. 



spermatozoa and equally vital ova are developed or ma- 

 tured from the crude parts of the blood. On the contrary, 

 both these primary organisms are derived from the most 

 vital elements of the total circulation, and are subordinate 

 to the quantity of its vital qualities. 



In the embryo stage of breeding, there can be no in- 

 crease by growth in any larger degree than the oxygenized 

 blood supply increases; and as this is closely proportioned 

 to breathing, and the breathing is closely proportioned to 

 exercise, — a fact that is practically recognized by horse- 

 breeders, who are careful to have their brood mares take 

 regular exercise, — it is clearly certain that an increase in 

 vitalized blood, and increase in embryo size, depend on 

 the natural extent of breathing and activity being regu- 

 larly maintained, as a necessary condition precedent to 

 making full vital growth and size in developing the embryo 

 before its birth and breathing. 



The suckling stage of breeding is naturally necessary 

 until the calf becomes able to graze and masticate food, 

 when this final stage of breeding ends. 



The milk is not colored, because the calf colors and 

 vitalizes its own blood by its own breathing ; but the nu- 

 tritive quality of the milk depends upon that of the cow's 

 blood — which varies widely, according to the ingredients 

 of the cow's food, and extent of its necessary vital quali- 

 ties, which again depends very much upon regular exer- 

 cise, which in its natural degree is as vitally necessary for 

 cows as for horses. 



We see this law practically in operation in the muscular 

 breeds of cattle, as the Devons, Galloways, Kyloes, Here- 

 fords, and generally in common cattle, in which there is 

 no lack of fertility, because there is sufficient exercise to 

 supply the necessary quality of blood that insures fer- 

 tility. 



It is evident, then, that infertility in inactive cattle of any 



