44 Feeds and Feeding. 



and studied. In some cases mechanical work is performed, while in 

 others the subject is at rest. Everything which passes into the 

 animal — air, food, and water — is carefully measured and analyzed 

 so that the exact intake of the body is known. The air is in turn 

 drawn from the chamber, and the solid and liquid excrements 

 passed by the animal are all likewise weighed and analyzed. If the 

 intake is larger than the outgo, the animal has increased in body 

 substance ; if less, it has lost. The respiration apparatus has been 

 used for studying the production of work and the formation of the 

 tissues of the body, both the lean flesh and the body fat. Thru this 

 means scientists have, in some measure, been able to determine what 

 becomes of the food of animals. 



61. A respiration study. — The following example from Henne- 

 berg^ of the Weende Station, Germany, illustrates the use of the 

 respiration apparatus. A full-grown ox weighing 1570 lbs. was 

 placed in the respiration chamber. During one day of the trial it 

 was fed 11 lbs. of clover hay, 13.2 lbs. of oat straw, 8.2 lbs. of bean 

 meal, and 2.13 oz. of salt, and drank 123.7 lbs. of water. The in- 

 take and outgo of the body for the day are shown in the table on 

 the opposite page. 



62. Intake of the body.— The table shows that during the 24 

 hours of the trial the intake of nourishment by the ox was as fol- 

 lows: 



Grams Pounds 



Oxygen taken by way of the lungs 7,255 16.0 



Dry matter taken into the alimentary tract 12,675 27.8 



Water drank and in food 58,200 128.0 



Total intake of the body for 1 day __ 78,130 171.8 



From these data we learn that during the 24 hours of study the 

 ox breathed in 16 lbs. of oxygen, ate 27.8 lbs. of dry matter, and 

 took 128 lbs. of water in food and drink, a total for the day of 

 171.8 lbs. 



63. Waste products. — Division B of the table records the losses 

 from the body as follows : 



Grams Pounds 



Passed off as so-called solid excrement 40,645 89.4 



Passed off as urine 13,900 30.6 



Bespiration products from lungs and skin 22,550 49.5 



Total waste from body during 24 hours 77,095 169.5 



Thus during the day of the trial there passed from the ox 89.4 



lbs. of the so-called solid droppings and 30.6 lbs. of urine, while the 



*Neue Beitrage, Gottigen, I, 1870, ji. XIX; Kraft, Lehrb. Landw., Ill, p. 17. 



