in most ranches rather imperfectly met. .Although apples are fed 

 liberally in certain of the more successful ones, in the majority 

 they are used very sparingly if at all. There is much to be said 

 for their regular inclusion in the diet. 



After this general discussion of feeding practice in the fox 

 industry it remains to consider which, if any, among the actually 

 prevalent sources of damage or loss may be in whole or in part 

 the consequence of imperfect nutrition. The list of reported 

 complaints in which a nutritive defect of some sort may with reason 

 be suspected to be a factor is, as a matter of fact, quite large. It 

 would include, e.g., rickets, convulsions, sore eyes, still births, the 

 abandoning or even the killing and eating by the mother of her 

 young, premature cessation of milk supply, early death of the young, 

 failure to grow, failure to reproduce, and imperfect development 

 of fur. 



During recent years there have been conducted in different 

 laboratories a great variety of experiments in which rats, guinea 

 pigs, swine, or other animals have been subjected for longer or 

 shorter periods to the influence of variously restricted diets. 

 Among the results of these experiments one may find, singly or 

 in various combinations, every one of the abnormal conditions 

 just mentioned. This does not necessarily mean that these are 

 always to be attributed to a dietary factor. The habit of killing 

 and eating the young, for example, may be merely a vice, inherited 

 or acquired, in which case there is nothing to be done but to destroy 

 the animal. What the experiments referred to demonstrate is 

 that this, and the other conditions named, may be, and doubtless 

 often are, the consequence of improper feeding. It is probable 

 that most of them would become much less common if the foxes 

 could be assured a diet which supplied continuously each and all 

 of the factors essential to perfect nutrition. 



Incidentally it may be pointed out that we do not know 

 definitely the normal duration of lactation in the fox, nor its 

 normal growth curve. These furnish problems that should not be 

 forgotten in any experimental study of the growing fox's nutrition. 



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