200 THE SCIENTIFIC FEEDING OF ANIMALS 



periments and observations along this line have given conflicting results. 



If equivalent amounts of carbohydrates and albumens are replaced by 

 easily assimilable fats, provided that the amount of fat does not exceed 

 0.5 to 1 pound per 1,000 pounds live weight, per day, the milk yield will 

 not only be increased in amount but in fat content as well. Larger amounts 

 of fat (1.5 to 2 pounds per 1,000 pounds live weight) will only occa- 

 sionally have the same effect; frequently their effect is negligent or less 

 than that of smaller amounts. The nutrient fat of the ration, as such, 

 enters into the composition of the milk to a very limited extent. It seems 

 that a direct transfer of the nutrient fat into milk occurs only in so far 

 as the presence of stearin, palmatin and olein is concerned. According 

 to investigations of Henriques and Hansen and others, it is known tliat 

 certain other fats (salicinic and linoleic acids) are not excreted with the 

 milk. 



A few words should be added with reference to the effects of so-called 

 specific milk-producing feeding stuffs. These effects would be assumed 

 to be independent of the digestible nutrient content of the substances in 

 question, but due rather to their effect upon palatability and on the activ- 

 ity of the digestive glands. It has been found that palmseed cake, as 

 compared with ground corn and peanut meal of equal starch value and 

 digestible albumen content, actually possesses this property to some de- 

 gree. Cocoanut cake, and corn distillery slop and, to a moderate degree, 

 linseed cake, cottonseed meal and dry brewers' grains, as well as the 

 leguminous seeds (vetches and peas), increase the fat content of the 

 milk without affecting the amount. Maizena and, in a more moderate de- 

 gree, com and oats, increase the quantity of milk secreted, but the per- 

 centage of fat is reduced so that the total remains practically the same. 

 Camelina sativa (false flax) and poppy-seed cake, as well as rice feed 

 meal, have an unfavorable effect in this respect. The ethereal oils and bit- 

 ter principles are also classed with the specific milk-producing substances 

 (galactopoietics), e. g., fennel, anise, caraway, coriander, juniper berries, 

 calamus root, gentian root, jaborandi leaves (pilocarpin). Certain sul- 

 phur preparations, flowers of sulphur, antimony sulphid and bicarbonate 

 of sodium also belong to this class, 



Morgen and his co-workers, as well as Fingerling, have shown that a 

 certain content of aromatic substances (ethereal oils) in feedings stuffs 

 actually influences milk secretion. In an experiment conducted with two 

 lots of sheep and goats, the one receiving good quality aromatic meadow 

 hay, the other straw, starch, gluten, tropon by-products, sugar, prepared 

 lime and hay ash, while the rations for each lot contained the same 

 amount of digestible nutrients and had practically the same starch values, 

 the meadow hay ration produced the largest yields of milk. After add- 

 ing condimental feeding stuffs, fennel, anise, hay distillate or hay extract 

 and malt sprouts to the second ration, and subtracting a corresponding 

 amount of digestible nutrients, the milk yield and fat production almost 

 equalled that from the meadow hay ration. The same favorable effects 



