178 FEEDS AND FEEDING 



Recent investigations have shown that in some instances flax seed may 

 contain a compound which, when acted upon by an enzyme in the seeds, 

 yields the poison, prussic acid. This enzyme is destroyed by the heat to 

 which the ground flax seed is ordinarily subjected in both the old and the 

 new process of oil extraction. In view of this and bearing in mind that 

 linseed meal and cake have been fed on vast numbers of farms in this 

 country and abroad with the best of results, we may still consider these 

 feeds among the safest and most beneficial of concentrates. In making 

 gruel or mash from untreated flax seed, it is advisable to use boiling 

 water and keep the mass hot an hour or two, to destroy any prussie-acid- 

 f orming enzyme in the seed. 



253. Old- and new-process oil meal. New-process linseed meal carries 

 an average of 3.0 per ct. more crude protein than old-process meal, but it 

 contains only about 2.9 per ct. of oil or fat. The crude protein of the 

 new-process meal is slightly less digestible than that of old-process meal, 

 but owing to its higher total crude protein content, the new-process meal 

 supplies somewhat more digestible crude protein. The new-process meal 

 is slightly less palatable and has less of a beneficial laxative effect than 

 old-process meal. Practically all of the linseed meal is now produced 

 by the old process. 



254. Linseed meal as a feed. There is no more healthful feed for 

 limited use with all farm animals than linseed oil cake or oil meal, with 

 its rich store of crude protein, slightly laxative oil, and its mucilaginous, 

 soothing properties. Its judicious use is soon apparent in the pliable 

 skin, the sleek, oily coat, and the good handling quality of the flesh of 

 animals receiving it. It is therefore very useful as a conditioner for run- 

 down animals. Linseed meal is one of the most popular dairy feeds (599) , 

 and is excellent for horses. (487) It isi also one of the best protein-rich 

 supplements for fattening cattle and sheep (753, 855), and gives good 

 results with swine when fed in proper combination, but it should not be 

 fed as the only supplement to pigs not on pasture. (973) Rich in pro- 

 tein and calcium and fairly high in phosphorus, linseed meal is well 

 suited to young growing animals. Owing to its popularity, linseed meal 

 is often expensive compared with other protein-rich feeds. It is then 

 economy not to use it as the chief source of protein but to feed only 

 enough to produce the desired tonic and regulating effect. 



In this country the demand is chiefly for linseed meal instead of the 

 unground cake, probably owing to the fact that it is fed mostly to dairy 

 cows mixed with other concentrates. For sheep, cake ground to nut or 

 pea size is more palatable. European farmers commonly purchase the 

 cake in slab form and grind it in cake mills before feeding. In this form 

 there is no chance for adulteration. 



255. Low-grade linseed meal; other flax by-products. On account of 

 the high reputation held by linseed meal, some concerns are placing on 

 the market products made of mixtures of linseed meal and flax screen- 

 ings or screenings oil feed (flax screenings from which some of the oil 



