320 POULTRY PRODUCTION 



in disposition. Birds are more active, have a higher tempera- 

 ture, and more rapid digestion. As a rule, six months 

 represents the age of maturity and four or five years the life 

 period. 



With these things in mind it is easy to see that all of the 

 body processes must be extremely rapid. The relation 

 between feed and these productive processes, while no closer 

 in point of composition than is the case of other domestic 

 animals, in point of time is very much closer. 



The result of wrong feeding is more quickly disastrous 

 than with any other class of stock, and for the same reason 

 that brealcage is likely to be more serious in a high-geared 

 as compared with a low-geared machine, the disaster caused 

 by wrong feeding, particularly during the growing period, 

 is more likely to be so serious as to be permanent. With 

 slower-growing animals there is more opportunity for 

 recovery and repair. 



Physiological Efficiency of the Laying Hen. — In the amount 

 of edible food solids manufactured as compared with the 

 weight of the dry matter in her body the hen leads all farm 

 animals. As shown in Table XXVIII, a three and a half 

 pound Leghorn hen, laying two hundred eggs in a year, 

 produces five and three-quarter pounds of edible-food solids, 

 or 3.8 times the amount of dry matter in her body. The 

 cow is the only farm animal which is at all comparable with 

 the hen in this particular. 



A Jersey cow weighing 1000 pounds, giving 7000 pounds 

 of milk containing 14 per cent, solids, would rank as high, 

 if not higher, among dairy cattle than the hen mentioned 

 would rank among high-producing hens. Such a cow would 

 produce 2.9 times her own dry-matter weight in solid food. 



Table XXVIII. — A Comparison of the Hen and the Dairy Cow 

 IN Physiological Efficiency. 



Dairy cow, Hen, 



pounda. pounds. 



Gross weight , 1000 3.5 



Dry-matter weight . . 340 1 . 5 



Edible solids produced in one year 980 5 . 75 

 Proportion of dry matter of the body 



to edible solids produced . . . . 1 to 2.88 1 to 3. S3 



