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47- New Feeds and their Value for Agriculture.
HONCAMP, F.: Neuere Futtermittel und deren Wert für die Landwirtschaft.
The following is a report on the results of experiments carried out by the writer on the feeding and fattening of live stock at the Rostock Experiment Station, with the object of determining the value of foods recently put upon the market.
Dry Beer Yeast. Delbrück calculates that the German breweries turn out every year about 70 000 tons of fresh yeast which hitherto were more or less allowed to run to waste.
Air-dried yeast contains from 40 to 45 per cent. of raw protein; it is consequently a concentrated vegetable food rich in proteids which might find useful employment as complementary food in the fattening of pigs.
For drying beer yeast there are a number of apparatus of the usual type; vacuum drying has also been attempted, and this would have the advantage of requiring lower temperatures and consequently avoiding those alterations which diminish the digestibility of the albuminoids.
In the writer's experiments sheep utilized, in their maintenance rations, from 89 to 93 per cent of the proteids contained in the dry yeast; the same coefficient of digestibility may be, admitted for pigs also. Fattening experiments carried out with sheep and with growing pigs have shown that for sheep, dried yeast as a complementary proteic food had the same value as a mixture (of equal starch and proteid value) of cottonseed meal and sesamum cake as well as oil-free soy cake. Similar results were obtained with pigs which were fed dry yeast in comparison with fish and meat meal. These experiments will be repeated. As for cows, the writer reports that they refused all food containing even small quantities of dried yeast. The price of this substance is not high: from 8 to 9 shillings per cwt.
New by-products of oil making are: Guizotia oleifera cake (Nigerkuchen) and Perilla cake; according to the writer the former contains in its dry matter about 36 per cent. of crude protein and 6 per cent. of fat; the latter 41 per cent. of protein and 8 per cent. of fat. The digestibility is respectively 87 and 91 per cent. for Guizotia cake and 87 and 88 per cent. for Perilla cake. These figures are approximately the same as those of other oil cakes. Hansen fed Guizotia cakes to sheep and found that their dietetic action was not good. Considering that both Guizotia and Perilla cake are made from small hard seeds relatively rich in silica and for which high pressures are necessary, the writer does not think it advisable that they should gain a footing in the market, unless they could be sold at a very low price.
The dry matter of rye germs contains 31 per cent. of protein and 9.7 per cent of fat; wheat germs 32 per cent. of protein and 7.8 per cent. of fat. Of the protein of the latter food 94 per cent. was digested by sheep and 90 per cent. by pigs; of the former food 92 and 91 per cent. respectively. Sheep digested 89 per cent. and pigs 86 per cent. of the crude fat
of wheat germs, while the respective figures for rye germs were 90 and 72 per cent. They are thus feeds rich in albuminoids and especially easy of digestion, and much relished by all kinds of live stock. Wheat and rye germs are not usually found separately, but pass together with the bran into the siftings. When however they are isolated, they can be advantageously fed fresh, that is before being allowed to become rancid, to all kinds of live stock as complementary albuminoid food
Among the foreign pulse that has recently appeared on the market the following may be mentioned: the Calcutta-pea (Kalkutta erbse), the chickpea (Cicer arietinum) and the chickling vetch (Lathyrus sativus); the two latter were considered poisonous, but this view seems to have been contradicted by the present observations and experiments, at least for the chickpea, while the chickling vetch might under certain conditions be poisonous. It is perhaps something similar to what happened about 1870 with lupins, which on being fed produced widely spread disease, so-called "lupinosis", that for several decades past has not reappeared.
The writer has instituted experiments on the digestibility, on the part of animals, of these various kinds of pulse Digestive tests in vitro, have given the following percentages of digested protein :
The use of chickling vetches appears, at present at least, not to be advisable, and according to practical men chickpeas should not be fed to horses in which they seem to cause broken-windedness
The so-called molasses feeds in general consist of substances possessing very little or no nutritive value, mixed with molasses. In order to prevent the trade in these feeds, the special legal tariff No. 3 allows only those molasses feeds in which molasses is mixed with only one explicitly declared substance. Among the absorbents recently used, there is solubilized sawdust, that is sawdust treated with sulphuric acid under pressure in order to transform the lignin and cutin into dextrose (20 to 25 per cent), with the object of rendering it more palatable; it is fed warm and mixed with a certain quantity of warm molasses. It was stated to have a high nutritive value, but the analysis made by the writer on the dry matter yielded the following results :
thus showing that the treatment does not modify the composition of the sawdust to any great extent. Nevertheless a portion of the cellulose is transformed into sugars (diminution of crude fibre and increase of nitrogen
free extract). The writer therefore conducted some experiments with the view of ascertaining how these sugars were utilized by animals
The results of his experiments tallied with those of other previous investigators, and showed that crude sawdust, besides not being utilized, actually diminishes the digestibility of other feeds mixed with it. Solubilized sawdust does not come up to the level of the straw of winter cereals, and when mixed with molasses ("bastol ") its digestibility is practically nil. The price demanded for solubilized sawdust is 8 shillings per cwt. a grossly exaggerated price.
It has been also suggested to mix sawdust with warm distillery byproducts, but even this method does not yield utilizable feeds. Some years ago pine needles from which the resinous and tannic substances had been extracted were suggested as an absorbent for molasses. But experiments carried out then by the writer with maintenance rations showed that between the degree of digestibility of natural and exhausted needles there was no sensible difference. Recent experiments conducted by W. Schneidewind on sheep with fattening rations fully confirm the above results.
Lupins, on account of their bitterness, are not palatable to live stock, with the exception of sheep. The usual methods adopted to eliminate this bitterness are not economic. Herr H. von Fehrenteil has constructed an apparatus in which the lupins are first steamed in a Henze vaporiser, mixed with potatoes, then crushed and dried between hot rollers. According to analyses made at the suggestion of the writer, the percentage of these "lupin flakes was the following:
It is therefore a highly digestible product; but not even Fehrenteil's process has succeeded in eliminating all the bitterness, whilst the process of drying is perhaps still too expensive.
48 Hydrocyanic Acid from Linseed Cake.
The Journal of the Board of Agriculture, Vol. XIX, No. 8, pp. 657-660. London, November, 1912.
1. Feeding Experiments. Experiments have recently been conducted by the Board of Agriculture and Fisheries of Great Britain with a view to determining the effect, if any, produced on cattle by feeding with linseed cake yielding a high percentage of hydrocyanic acid on digestion with water. From a parcel of linseed, yielding 0.026 per cent. of hydrocyanic acid, cake cold-pressed at a temperature not exceeding 97° F., and cake hot-pressed
at a temperature of 160° F. were prepared. The cold-pressed cake yielded — on treating with water-0.038 per cent. of hydrocyanic acid. This cake was fed to a heifer, 14 lb. being given each day for eight consecutive days, but no ill effects were produced on the animal. Another heifer was fed on the hot-pressed cake, yielding 0.032 per cent. of hydrocyanic acid. This heifer also received 14 lb. of cake per day for eight consecutive days and no ill effects resulted.
The above rations are very much larger than would ordinarily be given, and the linseed cake contained an exceptionally high percentage of hydrocyanic acid.
2. Effect of Heat on the Ferment giving rise to Hydrocyanic Acid in Linseed. In the case mentioned above, nearly the same amount of hydrocyanic acid was obtained from the hot-pressed cake as from the coldpressed cake on digestion with water. This result was contrary to the generally accepted view that the activity of the ferment in the linseed on the cyanogenetic glucoside, is destroyed by the heat applied in expressing the oil during the hot-press method of preparing linseed cake. It appeared desirable, therefore, that further samples should be examined in order to ascertain whether hydrocyanic acid corresponding in amount with that present in the original linseed is produced by digesting hot-pressed cake with water. The following results were obtained:
A direct comparison of the absolute percentage of hydrocyanic acid yielded by the seeds and by the cake (column 3 of the above table) is without value, as the result of removing oil from the seed is to increase the proportions of the remaining constituents in the cake. In order to ascertain whe
ther any change has taken place in the activity of the enzyme in regard
In a paper published in the Journal of the South Eastern Agricultural College (No. 20, 1911, p. 289) Dr. Auld states, with reference to the examination of a large number of oil cakes, that in no case was a diminished rate of formation of prussic acid noted in cakes of lower oil content which might be assumed to have been pressed at a higher temperature or kept under the influence of heat for a longer period. This statement tends to confirm the above results.
49- Supply of Store Cattle and Slaughter of Young Cattle in Great Britain.
The Journal of the Board of Agriculture. Vol. XIX, No. 8, pp. 617-623. London, November 1912.
The problem of the rise in the price of store cattle and the extent to which young calves are slaughtered has already been dealt with in the Journal for August, 1911 and for April, 1912.
The statistics published by the Board of Agriculture show that in the period from 1906 to 1910 the average price of stores rose by about one-seventh. Exact figures showing the number of calves slaughtered each year are not available, but there is no doubt that, leaving out of account purely dairy breeds, such as Ayrshires and Jerseys, the proportion slaughtered to the number reared is very considerable.
It is sometimes suggested that the rise in the price of stores is due to an actual falling off in the supply; this, however, is clearly not the case, for, leaving out of consideration the abnormal year 1911, the number of store cattle imported from Ireland has on the whole steadily increased in the last few years, while the number of cattle in Great Britain, other than cows or heifers in calf or in milk, has remained almost stationary.
As is shown by the following figures, the rise in the price of store cattle during the last few years is almost exactly in proportion to the rise in the value of beef.
At first sight, it seems remarkable that the increase in price has not apparently resulted in any corresponding increase in the supply. The question, however, is not a simple one of supply and demand, but is complicated by the fact that in Great Britain the farms on which the cattle industry is carried on are, to a great extent, sharply divided into three classes: 1) dairy farms, on which a large number of calves are bred, but where few are reared; 2) rearing farms (having a quantity of cheap grass land, which