508 A STUDY OF FARM ANIMALS 



able yellow yolk, while most other grains produce less color. 

 Green food and clover or alfalfa hay also furnish the high 

 color to the egg so commonly seen when these foods are fed. 

 Forced feeding of fowls may be done in two ways, one 

 when the feeder simply gives the birds more feed than they 

 need or would eat under natural conditions; the other being 

 a special artificial feeding process known as cramming, 

 whereby the crop is filled with food by the use of a machine, 

 and the fowl fattened as rapidly as possible. Of course 

 what would be a forced feeding of one fowl might not be of 

 another, because of difference in capacity. 



On this subject of forced feeding Robinson says:* 

 "Forced feeding is almost universal among poultrymen. All regular, 

 good feeding is in a sense forced feeding. Even under natural conditions 

 with opportunity to balance their own rations, full-fed poultry develop 

 faster and better individually,but at the cost of shorter life and reduc- 

 tion of vitality in the offspring. The poultryman's _ object is to get 

 as much as possible out of the birds in the shortest possible time; that is, 

 to market as soon as possible those destined primarily for the table, and 

 to keep laying and breeding poultry only as long as they are highly 

 productive. He forces by feeding, but not (intentionally) to the danger 

 point, just as a careful horseman often drives his horse much faster and 

 farther than the horse would go of its own accord, yet avoids over 

 driving." 



The use of mineral foods by fowls is even more important 

 than with farm animals. Growth in proportion is really 

 much greater with the fed fowl than the four-footed animal, 

 while the production of eggs requires a considerable amount 

 of mineral matter. The common supply of food docs not 

 always furnish enough of the mineral substances, and espe- 

 cially lime, to meet the needs of the fowl. This lack is par- 

 ticularly true of the laying hen. Consequently some 

 other material must be added, and green ground or broken 

 burned bone, granulated dry bone, and finely broken stone 

 are commonly used to meet this need. Ground or finely 

 broken oyster shells have always been popular for laying 

 hens. As to the exact needs of the body for mineral food, 

 we do not know, but it may be assumed, as based on practice 

 and the result secured with farm animals, that the mineral 



*Principles and Practice of Poultry Culture. 1911, page 213. 



