HOW TO FEED POULTRY FOR ANY PURPOSE WITH PROFIT 



The Digestive Organs of Poultry 



There are some things in the feeding of poultry that 

 are better understood if one keeps in mind the resemb- 

 lances, as well as the differences, in the three types of di- 

 gestive system which are found in our domestic animals 

 and birds. 



The horse masticates its feed thoroughly as it takes 

 it into the mouth; the feed then passes into the stomach, 

 where digestion takes place, and from this into the small 

 intestine where it is assimilated. 



In the pig the digestive system and the processes are 

 similar to those in the horse, but mastication is not so 

 thorough. Pigs cannot digest dry fodders and hard grains 

 as fully as horses do, although they have strong teeth 

 and powerful jaws. 



In the ruminants cows and sheep there are said to 

 be four stomachs, though only the last in the series is 

 properly a stomach. A cow partly masticates her feed as 

 she eats it. When the feed is swallowed it passes into the 



first stomach or 

 paunch, which is 

 so connected 

 with the second 

 stomach that the 

 contents shift 

 back and forth 

 from one to the 

 other with a 

 churning motion. 

 After a period of 

 this action the 

 feed passes into 

 the third stom- 

 ach where it 

 forms into balls, 

 which are re- 

 turned to the 

 mouth for com- 

 plete mastication. 

 When swallowed 

 this time it pass- 

 es into the fourth 

 stomach, which 

 is the true stom- 

 ach, and from 

 there to the in- 

 testines. 



We are accus- 

 tomed to say 

 that birds have 

 no teeth, but the 

 beaks and bills of 



birds are to all intents and purposes a combination of 

 incisor and canine teeth. So birds have teeth for biting, 

 cutting and tearing, but not for mastication. The throat 

 is very wide in proportion to the size of the creature, 

 and the gullet capable of great distention. Birds can 

 swallow feed in much larger pieces in proportion to their 

 size, than most other animals can. 



The feed swallowed by a bird passes into the crop, 

 which is an enlargement of the gullet. In the land birds, 

 fowls, turkeys, etc., the crop is globular and quite large. 

 In ducks, geese, and other aquatic birds, there is no such 

 distinct development of the crop, but the whole gullet 

 is capable of great distention, and when the birds are able 

 to eat greedily of a bulky feed, this distention of the 

 gullet may be observed the entire length of the neck. 



THE DIGESTIVE ORGANS OF 

 THE FOWL 



a, Tongue; (upper bill removed); b, 

 Esophagus; c, Crop; d. Esophagus; e, 

 True Stomach; f, Gizzard; g, Duode- 

 num; h, Small Intestine; i, Caeca; k, 

 Rectum; m, Cloaca; o. Liver; p, Spleen; 

 r, Gall Bladder; s, Pancreas. Courtesy 

 of the New Jersey Experiment Station. 



From the crop of a bird the feed passes into the 

 stomach proper, which is a very small organ, and from 

 that to the gizzard a muscular sac having for its inner 

 surface a thick, tough, corrugated skin. Here it is re- 

 duced to a pulp, and in this condition it passes to the in- 

 testines. According to traditional popular belief the giz- 

 zard itself is not capable of masticating the feed, and to 

 assist it in that function the bird swallows bits of 

 gravel or any hard substance that will give a number of 

 sharp cutting edges. Full discussion of that matter is 

 deferred to the appropriate place in the discussion of 

 feeds, but it may be pointed out here that in birds the 

 feed is subjected to the strong action of the gastric juice 

 before going to the gizzard, while in animals which mas- 

 ticate their feed completely in the mouth, the action of the 

 gastric juice comes after mastication. 



Nutritive Requirements of Poultry 



The body of a bird consists of a framework of bone, 

 to which are attached the muscles that control it; a per- 

 manent external covering of skin, in which grows a 

 changeable covering of feathers; and the internal organs 

 of respiration, circulation, digestion, sensation, and re- 

 production, which are required to sustain the organism 

 and the species. Most of the internal organs are essen- 

 tially enlargements and peculiar developments of the 

 skin which lines the inside, just as it covers the outside 

 of ihe body. 



Certain facts about the composition of the body are 

 apparent on ordinary observation. We can see that the 

 skeleton contains a great deal of lime, and in the body 

 of a bird that was in normally good condition when killed 

 we can see more or less fat. We also see that this fat 

 is in different amounts in different birds, and often in 

 different places. And observing birds that were known to 

 be in health, and perhaps producing well when killed, 

 though not in what we consider prime condition for the 

 table, we naturally and rightly infer that fat is not an 

 essential part of the organism as are the bones, muscles, 

 skin, etc. In extremely fat birds it is easy to see that 

 the excess of fat may both hinder locomotion and interfere 

 with the functions of the internal organs. 



The mineral matter of the bones and the fat. when 

 present, are the only parts of the body of a bird in which 

 we seem to recognize elements of the body in form like 

 that in which they may be seen elesewhere. The rest of 

 the structure appears quite unlike the grains and vege- 

 tables which observation showed us make up so large a 

 part of the diet of our domestic birds. For information as 

 to the elements which compose flesh and feathers we 

 turn to the chemist. 



Chemistry tells us that flesh, skin, etc. of birds are 

 made of nitrogenous material to which is given the 

 general name protein. The chemical analysis of poultry 

 meat finds in it principally water, protein, and fat. The 

 substance of all fleshy tissues is formed from protein, 

 and it is customary to consider the fat found in them as 

 not an essential part of their structure. This, however, is 

 a too-narrow view, overlooking the function of the fat, 

 or oil, in various parts of the body in keeping it in good 

 order. Even the bones contain fat. Of the chemistry of 

 feathers we know little, for they have no feed value, and 

 chemical investigation in this line has so far been almost 

 entirely devoted to the things that are used to feed either 

 men or animals. It would appear, " however, that they 

 contain a considerable proportion of protein. 



The analysis of meat does not show the presence of 



