THE PACKINGHOUSE BY-PRODUCTS 217 



for feeding purposes. Of course, the high heat to which 

 tankage is subjected both during cooking and drying steriUzes 

 it completely. Thus, there is no danger of transmitting dis- 

 ease to a healthy animal through feeding properly prepared 

 tankage, or meat meal. No condemned carcasses are used 

 in the manufacture of the higher grades of these feeds, al- 

 though they are often used in the lower grades which are 

 usually used for fertilizer. Sometimes the lower grades are 

 sold for feeding purposes. Their use, however, is not ad- 

 visable. Peat and hair are sometimes used to adulterate 

 the lower grades of tankage. 



Tankage usually is sold on a guarantee that the protein 

 content will be not less than 60 per cent, which, of course, is 

 equivalent to 1200 pounds of protein per ton. Some tankages 

 are sold on a 50 per cent guarantee, likewise on a 40 per cent 

 guarantee, but the more highly concentrated goods are to be 

 recommended, inasmuch as the expenses per ton for prepara- 

 tion, bagging, shipping, and hauUng to the farm are the same 

 in the case of a 40 per cent protein tankage as in the case of a 

 60 per cent protein tankage. Consequently the more highly 

 concentrated goods figure much lower per unit of protein de- 

 Hvered on the farm. In addition to the protein, these feeding 

 tankages also contain about 10 per cent of fat, from 10 tol5 

 per cent of phosphates, and about 7 per cent of carbohydrates. 

 These supplementary constituents are very important, but 

 as a feeding tankage is bought principally on account of its 

 protein value, proper consideration should be given to the 

 amount of protein and the quahty of that protein when 

 purchasing a tankage for feeding purposes. Particular at- 

 tention should be given to the percentage of crude fiber, as 

 this is quite variable. If tankage contains much over 6 per 



