256 STATE BOARD OF AGRICULTURE. 



utilized by the cattle. The protein of wheat bran is also highly digesti- 

 ble, the digestion coefficient being 78. 



An examination of the records shows that what is true of the protein 

 in this respect applies with equal force to the carbohydrates and fat. 

 While the carbohydrates of the grains and by-products are very largely 

 •digestible, a good deal of the starch and other carbohydrates of the rough 

 forage is so encased in woody fiber as to escape the action of the digestive 

 fluid in the intestinal canal. Because of this variation in digestibility 

 among the forage crops and other cattle* foods it has been found neces- 

 sary to try digestion experiments with each of them. To insure accuracy, 

 these experiments have been carried on with at least two animals at a 

 time and in most cases have been repeated several times, the results being 

 in the main concordant. 



It is evident that in estimating the value of a given cattle food we ought 

 to take into consideration the digestible part only. The share of the 

 protein for instance that, under ordinary circumstances, passes through 

 the cow undigested is of no value as far as she is concerned and should 

 not be counted upon in calculating the amount of material she should re- 

 ceive in her daily ration. In comparing two fodders also it is not enough 

 to know how much of the total nutrients each contains, we must know in 

 addition the share that is digestible. Having determined the proportion 

 of digestible protein, carbohydrates and fat in each of our fodders we 

 will thereafter take account of those digestible parts only. For instance 

 in the clover hay above but 52 per cent of the 12.3 per cent of protein was 

 digestible, or 6.4 per cent. While there was 24.8 per cent of crude fiber 

 in the clover hay but 47 per cent of it was digestible or 11.65 per cent of 

 the clover hay was digestible crude fiber. Of the 38.1 per cent of nitrogen- 

 free extract but 61 per cent was digestible, or 23.24 per cent of the clover 

 hay was made up of digestible nitrogen-free extract. In the same way re- 

 membering that but 48 per cent of the fat was digestible we find that the 

 clover hay contained 1.58 per cent of digestible fat. The digestible crude 

 fiber and digestible nitrogen-free extract are of equal value and are com- 

 bined for the digestible carbohydrates. The 11.65 per cent of digestible 

 crude fiber added to the 23.24 per cent of nitrogen-free extract makes 

 34.89 per cent of digestible carbohydrates. Summing these results of the 

 combination of the chemical analysis of clover hay and the digestion ex- 

 periments we have the conclusion that clover hay contains 6.4 per cent 

 of digestible protein, 34.89 per cent of digestible carbohydrates and 1.6 

 per cent of digestible fat. 



COMPOSITION OF FEEDING STUFFS. 



Chemical analyses have been made of all of our common feeding stuffs 

 at the Experiment Stations in the different States. The average of a 

 large number of analyses has eliminated the errors which might have 

 been suspected had but one or two tests been made. With most of the 

 feeding stuffs digestion experiments have been performed. In the fol- 

 lowing table these results have been brought together and the table sets 

 forth the amouDt of dry matter, which the given fodders contain and in 

 the succeeding columns the per cents of digestible protein, carbohydrates 

 and fat. 



