4 INVESTIGATION IN ANIMAL NUTRITION 



converted feed to both milk and gain in body weight. In the experi- 

 ment on the food of maintenance there was also some slight gain in 

 body weight. In order to make even approximate deductions of the 

 nutriment actually required for the production of a given unit of dairy 

 product, and the amount of nutriment actually required for the main- 

 tenance of a given weight of animal body, it was necessary to know 

 the amount that was diverted to gain in body weight. There were no 

 available data on this point. Experiments in feeding for gain in 

 weight had been conducted for the purpose of calculating the cost of 

 gain, the amount of gain to a given quantity of grain or roughage con- 

 sumed, and in a few cases, the amount of dry matter consumed to a 

 given gain ; but nothing had been done in regard to the nutriment re- 

 quired for a pound of gain. To get some information on this point, 

 all feed-stuffs consumed by the seven calves from birth until they 

 weighed, on an average, 1,000 pounds, were weighed and analyzed, and 

 complete computations were made of the feed consumed, its nutriment 

 content, and the relation of nutriment consumed to gain in body weight. 

 The data were not then offered for publication because they related 

 to matters not entirely within the province of the Division of Dairy 

 Husbandry. 



In 1907 the experimental and educational work of the Division of 

 Dairy Husbandry was enlarged to include animal nutrition, and provi- 

 sion was made for the equipment of an analytical laboratory and the 

 employment of analysts. During the winter of 1907-08 it was decided 

 to inaugurate a series of experiments with beef -bred calves to de- 

 termine their composition by making a complete chemical analysis of 

 a fairly representative one at each period of 100 pounds gain in weight, 

 and also to keep a complete record of all food consumed by each ani- 

 mal and the dry matter and digestible nutrients required for production 

 to the various stages of growth. 



All the steers employed in the investigation in animal nutrition with 

 respect to beef -production were kept in the barn during their life- 

 time, except that half the steers from Groups III, V, and VII were 

 turned to pasture when they were one year old. During the first year 

 they were all kept in small portable stalls. During the second year 

 those that were retained in the barn on continuous stall-feeding had 

 the freedom of a runway in the barn, and were confined in portable 

 stanchions only while they were eating their rations. For this purpose 

 each steer was assigned to a definite place in the row of stanchions. 

 Each steer was tagged on the ear with a number corresponding with 

 the number over the stanchion to which he belonged. By strictly ad- 

 hering to this method, each one soon knew his place. On each manger, 

 numerals were placed with crayon showing the pounds of grain, hay, 

 and silage that made up his daily ration. Each steer always received 



