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Show Food Value of Potatoes for Livestock (By H. M. CHRISTENSEN) It is well known that potatoes have been used for years as food for livestock live-stock on an extensive scale in certain European countries and to a lesser degree in the United States and Canada. Can-ada. In this country, the feeding of potatoes is limited very largely to the present, when there is a considerable- surplus of potatoes above the needs for human consumption and the prices are unusually low, one may well consider the value of potatoes for feeding livestock and the feasibility feasi-bility of diverting considerable portions por-tions of the crop to that use in an attempt to obtain for the crop as a whole, a fair and reasonable return. Considering first the composition of potatoes, it may be said that the average of 465 analyses show that j potatoes contain about 79 per cent of I water and 21 per cent of dry or solid matter. In other words, on the average aver-age about four-fifths of the potato consists of water and one-fifth of dry or solid matter. The composition of the dry matter in the potato is very similar to that of No. 2 dent com, except for a somewhat higher ash and lower fat content in the potato. The I dry matter of the potato contains 10.4 per cent of crude protein com- pared to 11.0 per cent in corn, 1.9 per cent of crude fiber compared to 2.2 j per cent and 82 per cent of nitrogen-I nitrogen-I free extract, chiefly starch, compared to 79.6 per cent in corn. From the ! standpoint of composition, then, we might expect that corresponding amounts of dry matter in potatoes and corn would have about the same feeding value. Both are low protein (Continued on page 5) utilization of potatoes at times when market prices are unusually low, as at the present time. We cannot expect to grow potatoes pota-toes primarily for the purpose of feeding livestock in this country for two main reasons. (1) It is usually possible to obtain a better price for the potatoes by marketing them for human consumption than is possible by feeding them to farm animals. (2) Because of the high water content con-tent of the potato and limited yields the amount of dry or solid material obtained per acre is low compared to that obtained from other crops such as corn. This also holds true when considered from the standpoint of the digestible material produced. Under Un-der ordinary conditions, therefore, food for livestock can generally be produced more cheaply from other sources than the potato. The desirability or advisability of using potatoes for feeding of livestock live-stock on an extensive scale must, therefore, be considered as a special i case resorted to in time of emergency I or expediency. At a time like the Potatoes Are Good Livestock Ration (Continued from page 1) feeds and should be used in rations properly supplemented with proteins. The capacity for consuming and digesting food varies with different classes of animals. Kellner reports that in 30 trials with cattle and sheep fed potatoes, presumably raw, 72 to 96 per cent of the organic matter was digested, or an average of 83 per cent. Woods at the Maine experiment station, in trials with four sheep, found that they digested di-gested 77 per cent of the organic matter in raw potatoes and 81 per cent in cooked potatoes. In other words, his results are similar to Kell-ner's Kell-ner's average. Kellner reports that in 13 digestion diges-tion trials with pigs, 91 to 90 per cent of the organic matter was digested, digest-ed, or 94 per cent on the average. Presumably, these trials were on cooked or steamed potatoes although that is not definitely stated. Kellner also reports that in two trials each on dried sliced potatoes and dried potato chips, the digestibility was 90 and 91 per cent, respectively, and that in 2 trials on dried steamed potato po-tato flakes the digestibility was 95 per cent. The actual digestibility in any given giv-en case will vary somewhat with the size and quality of the potatoes, having hav-ing relatively more surface and skins would show lower digestibility under otherwise similar conditions. The conclusions we may draw are that cattle and sheep digest about 83 per cent of the organic matter in potatoes, po-tatoes, and pigs abotft 94 per cent. A single experiment on a horse indicated indi-cated a value of similar to that obtained ob-tained with pigs. So far as digestibility digesti-bility is concerned, then, the potato compares favorably with No. -2 dent corn in which 91 per: cent of the organic or-ganic matter is digestible. Raw potatoes are not as palatable to cattle and sheep as good corn silage, mangels or turnips, but if they are reasonably sound and free from dirt, cattle and sheep will consume them readily with apparent relish if r. no other succulent feeds are avail- bushels potatoes; 1 ton corn silage from mature corn equals approximately approxi-mately 35 bushels potatoes; 1 ton corn silage from immature corn equals approximately 26 bushels potatoes. Putting the comparison on the basis of digestible nutrients another way: 4.8 lbs. potatoes will approximately replace 1 lb. of No. 2 corn; 4.6 lbs. of potatoes will approximately replace re-place 1 lb. of common barley; 4.1 lbs. of potatoes will approximately replace re-place 1 lb. of oats; one-half bushel or 30 lbs. of potatoes equals 29 lbs. of silage from mature corn; one-half bushel or 30 lbs. of potatoes equals 39 lbs. of silage from immature corn. In other words, 1 pound of potatoes will approximately replace 1 pound of corn silage. The comparisons just made indicate that it will take from 4 to 5 pounds of potatoes on the average to equal a pound of our common grain mixtures. mix-tures. According to the Scandinavian feed unit system, it takes from 4 to 7 pounds of potatoes to equal 1 pound of a good grain mixture or on the average, 6 pounds of potatoes are considered equal to 1 pound of a grain mixture in the rations of dairy cows. On the basis of the comparisons just made, it is interesting to compare com-pare the relative price values of potatoes po-tatoes with corn, barley and oats at different prices. If we take No. 2 corn at 68c per bushel, barley is worth 56q per bushel, bush-el, oats 32c and the corresponding value of potatoes would be 15c per bushel, which is not a very high price. With No. 2 corn at $1.13 per bushel, barley would be worth 93c, oats 53c and the potatoes 25c per bushel, all based on the same cost for digestible nutrients supplied- This does not give a very high value for potatoes. A short experiment at the North Dakota experiment station indicated that potatoes were but slightly less valuable than corn silage. This appeared ap-peared due in part at least to the fact that the cows did not eat quite enough potatoes to fully replace the silage. These and other experiments which could be cited amply demonstrate the feasibility of using potatoes in feeding feed-ing cattle. Milk cows should not be fed more able. While cooked or steamed potatoes pota-toes are both more palatable and digestible than raw potatoes, it is doubtful if it is either necessary or worthwhile to cook potatoes for cattle and sheep. Pigs do not relish raw potatoes and feeding experiments and practical experience ex-perience alike demonstrate clearly the advisability of cooking or steaming potatoes for hogs. There are different methods of comparing the relative value of feeding feed-ing stuffs and one of these is on the basis of the digestible nutrients they contain. If we compare potatoes with certain other feeds on the basis of digestibiliy, we obtain the following results: 1 bushel of potatoes contains 10.26 pounds of digestible matter; 1 bushel No. 2 corn equals approximately approxi-mately 4.5 bushels of potatoes; 1 bushel common barley equals approximately ap-proximately 3.7 bushels potatoes; 1 bushel oats equals approximately 2.1 than 25 to 30 pounds of raw potatoes per day for each 1,000 pounds of live weight. Larger amounts may injure the quality of the butter. It has been found that when cows eat a surplus of potatoes the time required to churn the butter is increased. The value of potatoes as dairy cow feed is comparable to that of good corn silage, ton for ton. It is reported that sunburned potatoes, po-tatoes, and especially sprouted stored potatoes, contain solanin, a poisonous compound. Where only a few sunburned sun-burned are present, this probably would never cause injury. If fed in large amounts, it might produce milk and butter of poor flavor. Cows require some green or succulent suc-culent food. Potatoes fed in moderate moder-ate quantities, such as referred to above, furnish this food and act as a laxative, keeping the cow's digestive tract in good, healthy condition. Large quantities of potatoes, however, may conclude that only the cooked potatoes pota-toes or potato products should be used for this purpose. Henry and Morrison, in summarizing summariz-ing the results of experiments at the Wisconsin station, at Copenhagen and at the Oregon station, conclude that it will take about 420 pounds of cooked potatoes to equal 100 pounds of corn or barley. This agrees fairly well with the comparison on the basis of digestible nutrients made earlier in this article. To obtain the best results, not more than 4 pounds of potatoes should be fed with each pound of grain. If the rations are properly balanced as much as 50 or 60 per cent of digestible diges-tible carbohydrates may be supplied by potatoes. Experiments and practical experience exper-ience alike would indicate that farm animals may) be employed advantageously advan-tageously in utilizing surplus potatoes pota-toes in years of over-production. cause scouring. Potatoes should be run through a root cutter or chopped well before being fed. 1 When given in a correct proportion, propor-tion, potatoes are satisfactory as a component in a well-balanced ration for poultry. The starch part of the potatoes will maintain the heat of tha body. They are cheap and easily prepared. pre-pared. ' To get the right proportion one must take into consideration the condition con-dition of the birds, as weather, winter win-ter or summer temperature, method of housing, extent of liberty, and whether the birds are expected to produce pro-duce eggs or merely put on fat and flesh. A good cheap diet used for layer1-that layer1-that are at liberty, is composed of equal parts by weight of potatoes and bran. The potatoes should be boiled and the brah mashed into them while hot. When mixed, this ration should be fed warm. If the weather is cold, some linseed oil or fat should be added. For confined layers, the proportion propor-tion of the potatoes should be reduced. re-duced. Malt culms or jsprouitB am very good in combination with potatoes. pota-toes. Corn meal, barley meal, or rice meal should not be fed in combination combina-tion with potatoes, for they lack protein pro-tein matter. For fattening poultry, large quantities quan-tities of potatoes can be used. Ducks, geese and turkeys fatten well on a mixture of potatoes and middlings. An egg-laying mash may consist of : 'he following, in the relative proportions propor-tions given: 10 lbs. of meat scraps, 10 lbs. of middlings, 10 lbs. of ground oats, 20 lbs. of bran, and 30 lbsf of cooked potatoes. Sheep will take raw potatoes nearly as well as cattle and can usually be fed up to 2 pounds of potatoes per 100 pounds of live weight. When being be-ing fattened as much as 4 pounds per 100 pounds of live weight can be safely fed in properly balanced rations. ra-tions. Horses are more easily affected by raw potatoes than either cattle or sheep, but according to Kellner, they may be fed from 3 to 5 pounds daily without trouble. Under careful supervision, super-vision, slowly working horses may be fed as much as 12 pounds per 1,000 pounds live weight. Henry and Morrison, on the authority of Pott, state that not more than 17.5 pounds should be fed per head daily. The greatest usefulness of potatoes pota-toes in the feeding of livestock is pobably with bogs. Hogs do not relish I raw potatoes, but they eat cooked or steamed potatoes greedily, especially if seasoned with a little salt. One-half One-half pound of salt to each 100 pounds of potatoes is probably sufficient although al-though more has been used successfully. success-fully. Since numerous experiments have uniformly shown "that raw potatoes are unsatisfactory for feeding hogs and that cooked or steamed potatoes I are satisfactory, it is reasonable to |