Chemical and Caloric Analyses 



A proximate analysis of representative samples of the components of 

 the ration as fed were made hy methods prescribed in the ninth edi- 

 tion "Book of Methods," Association of Official Agricultural Chemists. 

 Also composite air-dried feces were analyzed by the same methods to 

 calculate the total digestible nutrients of the rations. 



Nitrogen determinations were made on the fresh feces and urine to 

 complete the nitrogen balance of the rations. 



The gross energy of the feeds, feces, and urine was obtained by means 

 of an adiabatic bomb calorimeter. The caloric determination of the 

 fresh feces was made according to the method described by Colovos 

 et al. ( 1 ) . 



RESULTS AND DISCUSSION 



Table 3 shows the average digestion coefficients for the four rations 

 as fed. The dried beet pulp was significantly higher than the other ra- 

 tions in digestibility of the dry matter, energy, crude fiber, and nitro- 

 gen free extract. The digestibility of the protein in the dried beet pulp 

 was lower and the ether extract was significantly lower. The digestion 

 coefficients of the protein, fiber, and nitrogen-free extract of the dried 

 beet pulp were higher than those reported by Morrison (4) . 



The digestibility of the protein of the hay used in the experiment, 

 when fed as the sole ration, was higher than for the other three rations. 

 This value confirms previous results in this laboratory with early-cut, 

 well fertilized timothy hay (2). 



The average daily feed intake and gain in protein and energy on 

 each ration is shown in Table 4. Dried beet pulp fed alone showed a 

 significantly higher daily energy balance per unit basis than the other 

 rations. This was more or less expected due to the fact that dried pulp 

 is a high carbohydrate feed. The high retention of nitrogen, however, 

 was unexpected. Even though dried beet pulp did not have a very high 

 protein content, the amount eliminated in the urine was so low that 

 a relative high percentage of it was retained and the total retention 

 was higher than on any of the other rations. 



The average nutritive values of the dried beet pulp when fed alone, 

 in combination with hay, and with hay and a concentrate mixture are 

 shown in Table 5. Beside the conventional total digestible nutrients and 

 digestible energy values, metabolizable energy, and also net energy 

 figures are shown. 



The dried beet pulp had a higher value for total digestible nutri- 

 ent content than any of the other rations despite the fact that it was very 

 low in fat content. This value was higher than the values commonly 

 reported for beet pulp. The dried beet pulp also excelled the other 

 rations when the comparison was made on either the digestible energy, 

 metabolizable energy, or net energy basis. 



Summary and Conclusion 



Sixteen digestion and utilization experiments with four Holstein 

 steers were carried out to determine the nutritive value of dried beet 

 pulp fed alone, in a 50-50 ratio with hay, and with hay and a concen- 



