NUTRITION OF POULTRY 173 



In general, poultry use for food larger proportions of expensive 

 food products than other domesticated creatures, but as, under suit- 

 able conditions, they collect much of this class of foods for them- 

 selves, the comparative cost of feeding them is not as much greater 

 as the fact suggests. 



Note. Some analogies between organs of nutrition of birds and creatures 

 below and above them in the scale of evolution are also of peculiar interest to 

 the student of poultry culture. The most conspicuous resemblances between 

 domestic birds and animals in respect to nutrition are commonly noted and 

 their importance is often exaggerated. Thus : Poultry, being omnivorous, eat 

 everything eaten by cattle, which are herbivt>rous and granivorous ; there- 

 fore it has been assumed by some students of the science of feeding that the 

 nutritive rations worked out for cows will apply to poultry. ^ There is a 

 double fallacy in this view. Cattle are principally herbivorous, but use small 

 quantities of grain to advantage. Fowls are principaUy granivorous, but eat 

 considerable quantities of vegetables. Were there no other difference in the 

 diets of fowls and cattle, the fact that catfle eat chiefly of bulky foods and 

 lightly of concentrated foods, while fowls subsist more largely (and may sub- 

 sist for long periods exclusively) on concentrated grain foods, would suggest a 

 necessary difference in feeding standards. But fowls are also carnivorous and 

 insectivorous, using large quantities of highly nutritious animal foods. Such 

 differences suggest that the same feeding standards will not serve for both 

 classes of creatures. 



Cattle and horses have strong jaws and powerful molar teeth for the mas- 

 tication of the forage and grain that they consume. Hence, by analogy, it 

 was assumed that birds eating grain must have powerful organs to grind and 

 reduce it to form available for nutrition. Man and all domestic animals must 

 reduce food to such consistency and form that it will pass through a gullet 

 very small in comparison with the mouth and the size of the creature. Again, 

 by analogy, it was assumed that birds, so much smaller than man and domes- 

 tic animals, and having no teeth with which to reduce their food before swal- 

 lowing, must have food especially selected or prepared to meet the supposed 

 requirements of creatures of their size not provided with mechanical organs 

 of nutrition such as larger and stronger mammals possessed. Such analogies 

 have had a marked influence on the theory and practice of poultry feeding. 

 The fundamental error was failure to assign to birds their proper place in 

 the animal kingdom, and to consider the resemblances between their nutritive 

 organs and processes and those of creatures lower down in the scale. 



1 Singular and absurd as it seems, it is a fact that the earliest investigators of 

 the science of feeding poultry, instead of analyzing numbers of good rations for 

 poultry and ascertaining their average and using that as the standard, simply 

 took over the standards accepted for dairy cows and tried to apply them in 

 poultry feeding. 



