652 FEEDS AND FEEDING 



whether the proper amount to balance the ration is fed separately. There 

 is no advantage in feeding the tankage in the form of a slop or in 

 soaking it. 



966. Tankage alone vs. tankage plus other supplements. Tho tankage 

 is one of the best protein-rich supplements for swine, recent experiments 

 have shown in a striking manner that more efficient rations can be made 

 than merely tankage and grain, especially for pigs not on pasture. 

 Indeed, if young pigs under 50 Ibs. in weight are kept on only corn and 

 tankage continuously, without any green feed, not infrequently they 

 will eventually fail to thrive, even if they are fed yellow corn, which is 

 rich in the fat-soluble vitamine. (929) 



In trials at the Wisconsin Station by Morrison, Bohstedt, and Fargo a 

 mixture of half linseed meal and half tankage has proven decidedly more 

 economical than tankage alone for self-feeding, free choice, with corn to 

 pigs on pasture. For dry lot feeding a mixture including some chopped 

 alfalfa hay or alfalfa meal is advantageous, especially for young pigs. 

 For example, very good results have been secured at the Wisconsin 

 Station with a mixture of 2 parts tankage, 1 part linseed meal, and 1 

 part chopped alfalfa hay. (973) As is pointed out later, at the Iowa 

 Station Eward has found that pigs on pasture make slightly more rapid 

 gains when self -fed a mixture of 40 to 50 parts of tankage and the balance 

 of corn germ meal, along with corn, than when fed only tankage and 

 corn. (980) 



Careful investigations are just beginning to reveal the possibilities 

 of making much more efficient rations for swine than have been known 

 previously. Even our present knowledge shows, however, that the cost 

 of pork production can often be reduced materially by using one of 

 the combinations mentioned rather than feeding only grain and tankage, 

 especially to young pigs not on pasture. 



967. Blood meal. Blood meal is used but relatively little for swine 

 feeding, except sometimes for very young pigs, as tankage is usually a 

 more economical source of protein. This animal by-product is low in 

 both calcium and phosphorus, as it contains no bone. In a trial by Quick 

 and Spencer at the Virginia Station 84 blood meal was worth $3 per 100 

 Ibs. compared with skim milk at 25 cts. per 100 Ibs. (271) 



968. Fish meal. Tho fish meal has for years been fed to stock in 

 Europe, only recently has it been thus used in the United States. The 

 composition of the better grades of fish meal is quite similar to that 

 of digester tankage. Fish meal from various sources varies more or 

 less in composition and quite probably in feeding value. Recent ex- 

 periments have shown clearly that high-grade fish meal is even superior 

 to tankage as a supplement to the grains in swine feeding. The following 

 table summarizes the results of 11 trials in which fish meal has been 

 compared with tankage as a supplement to corn for pigs in dry lot. 

 The fish meal was in most cases the by-product of oil extraction from 



"Va. Bui. 176. 



