Principles and Practice op Stock Feeding 17 



To recapitulate. : 



Physiological standards are not absolute rules but average estimates 

 based on experimental work and upon the present knowledge of the physio- 

 logical needs of farm stock. They are calculated to produce maximum results 

 and omit considerations of cost and other important items. The Wolff, 

 Kuehn, Wolff-Lehmann and Connecticut standards are of this character. 



Practicable standards consider the cost of raw material and of product as 

 well as the yield^ and are variable. Their use should entail profit. They 

 may be said to be practically "home-made." They are the product of the 

 experience, observation and study of the individual feeder, though they are 

 often decidedly affected by the physiological standards. 



Average standards are simply the expression of average feeding prac- 

 tice, apart from all considerations of adaptation to special needs, or ability 

 to produce either large yield or profit. The Wisconsin standard, the Con- 

 necticut (32 ration) statement, and, perhaps, the Michigan standard are of 

 this sort. 



The remarks thus far made should serve to correct the misconceptions 

 prevalent among feeders as to the true function of feeding standards. They 

 are not rules but guides, not recipes but suggestions, not the mathematical 

 expression of discovered natural laws, but the concisely stated results of 

 practical experience linked with careful observation. They aim to state 

 amounts and proportions of the sundry nutrients advisable under general 

 and average conditions, or to indicate what in other and, often, many 

 hands has done good service without affirming that of necessity such a re- 

 sult will always be attained. These limitations once appreciated, the use- 

 fulness of the standards is great. If, however, they are used without a 

 clear understanding of their true character, they may become a stumbling 

 block rather than a stepping stone. 



The sundry standards thus far proposed, other than Kuehn' s, which 

 have but small vogue, are given in the appendix on pages 40-42. The orig- 

 inal Wolff standards were proposed over thirty years ago, but have recently 

 been revised by Lehmann, who has endeavored to make them harmonize 

 with the results of later experiments and experience. The only original 

 Wolff standard given — that for cows — is the one which has had much the 

 largest usage. 



2. the usefulness of feeding standards 



Sundry questions naturally arise in the feeder's mind. 



1. Why are the standards stated in terms of nutrients rather than of 

 fodders and feeds ? 



2. Which of sundry standards for the same animal shall be used ? 



3. When " doctors disagree " and when"ifs" and "buts" abound 

 may a farmer really find them useful ? 



