994 FEEDS AXI) FEEDING 



seed. It is calculated that the costs of carriage of this material from the 

 fields to the silos amounts to 650 000 dollars. It contains empty or broken 

 seeds of wheat, oats, barley and flax, with variable proportions of a large 

 number of weed seeds. The greater part is exported to the United vStates, 

 where it is screened once more for the production of different cattle feeds. 



Owing to the extreme smallness of the seeds of certain weeds, and the 

 hardness of some others, the}' cannot be crushed by the ordinary grinding 

 machinery. .Special plant is required, which is expensive in cost and oper- 

 ation, for the purpose of thoroughly grinding all impurities. If screened 

 again through a zinc screen with meshes of 1.8 mm so as to separate the very 

 smallest weed seeds, which are called black screenings, crushing can very 

 well be carried out with ordinary grinding machines, if the screening and 

 crushing are carefully done. This gets rid of about 40 °o "f the ordinary' 

 screenings. 



It must be remembered that feeds manufactured with screenings not 

 properly cleaned may contain thousands of live w^eed seeds per pound . Feeds 

 of this kind should not be given to cattle, as this might promote the 

 spread of weeds to the extent of causing thousands of dollars worth of 

 damage. 



The feeding experiments carried out with cows in milk, pigs, lambs and 

 chickens, showed that the blank screenings are valueless as a food and are 

 also exf :;nsive owing to the adulteration which the}'' cause. When mixed in 

 considerable proportions with another food they render it distasteful to all 

 livestock. Although by adding molasses to crushed screenings containing 

 their share of black screenings the food is rendered appetising, it is not eco- 

 nomical. In short, the cheapest way of rendering screenings palatable is 

 to remove the black seeds. 



The screenings, with their black part eliminated, may be given without 

 restriction to horses, cattle, sheep or pigs. It is preferable, however, that 

 they should not form more than 50 to 60 % of the total grain ration. Buck- 

 wheat screenings are particularly suited as food for poultry, but it seems 

 dangerous to give the latter linseed screenings. 



As the makers of threshing machines all claim that their machines are, 

 or can be, fitted with screens which are able to separate a large portion of 

 the waste in threshing, the Authors are of opinion that, if greater care were 

 taken in separating the grain during threshing, it would not only save the 

 cost of transport of the impurities, but the farmer woiild in this way be pro- 

 vided on the spot with a very useful feed which he couM employ direct on 

 his farm or sell to breeders. It should, however, b^ pointed out that weeds 

 cause enormous losses to farmers every year, so much so that though it is 

 desirable that everything of value as a food, such as screenings, should be 

 turned to account, it would be preferable to burn them rather than use them 

 in a way which might help the growth of weeds. 



To sum up, fnmi the practical point of view, the black screenings mu-st 

 be separated from the others and burnt, as they only reduce the nutritive 

 value of the other screenings comprising bigger seeds. They also form a 

 danger with regard to the spread of weeds. They have an appreciable fuel 



