This bulletin seeks to evaluate the matter in terms of results at the pail.

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2 .'.. The sudden and widespread growth in popularity of pelleted feeds has given rise to an acute problem in dairy production cirdes "shortage of alfalfa hay. The circumstance has added materially to the cost of roughage for milk production. This bulletin seeks to evaluate the matter in terms of results at the pail.

3 Alfalfa Pellets--Roughage or Concentrate By DONALD C. BROWN, H. S. WILLARD, JOHN W. HAMILTON, and }AMES READ* INTRODUCTION MANUFACTURE of dehydrated alfalfa pellets, a comparatively new industry, is growing rapidly. Pellets are high-grade alfalfa hay after dehydration and processing in a pelleting machine. They are cleaner and easier to feed in adverse weather since they will not blow in the wind and will not ball up or become moldy in rain or snow. Since these pellets are alfalfa, they are usually fed a a roughage, but some producers mix them with grain and feed them as a concentrate. In order better to understand the feeding value of dehydrated alfalfa pellets, comparison of their chemical composition is presented in Table 1 with that of alfalfa hay. and barley grain. TABLE I-Chemical composition of various stages of alfalfa hay compared with barleyt Alfalfa hay before bloom Alfalfa %, to full bloom Alfalfa hay dehydrated AJfalfa meal dehydrated Barley, all analyses tfrom Morrison's Feeds and' Feeding, 21st edition (4). Crude protein Fat Fiber percent percent percent N-free Mineral extract matter percent percent ccording to Table 1, dehydrated alfalfa meal has composition irnilar to alfalfa hay before bloom, but there is considerable decrease in protein and increase in fiber with increa e in amount of bloom. lfalfa dehydrated in different stages of bloom would have similar chemical composition to alfalfa hay. The chief difference compared with barley i in the fiber content, and it i the fiber content that differentiate roughage from concentrate. The fiber and the nitrogen. free extract or sugars and starche in a roughage are about a digestible to the cow a the fiber and nitrogenfree extract in a concentrate, but there is 0 much more fiber in roughage and so much more nitrogen-free extract in concentrates that the latter contain far more total digestible nutrient than roughage. Morri on place the total dige tible nutrient content of dehydrated alfalfa meal at 54.7 percent as compared with 77.7 percent for barley. Respectively: assistant dairy husbandman; dairy husbandman; associate research chemist; and dairy herdsman. Agricultural Experiment Station. -3- u LISR R'T 01'" THE IVERSlTV OF WYOMlNG L RAMIE 82071

4 It should be expected, therefore, that the buyer could not afford to pay as much for dehydrated alfalfa pellets a for barley. According to the Petersen method of evaluation (6), when barley is worth 55 per ton and oybean meal 92 per ton, one could not afford to pay more than $44 per ton for alfalfa meal or pellets. Experiments at Washington State Agricultural Experiment tations demon trate that milk production declined as dehydrated alfalfa meal replaced part of the concentrate mixture for dairy cows. Pelleted alfalfa, however, wa superior to the finely ground dehydrated alfalfa in digestibility and milk production (1, 3, 5). Pellets have the advantage over alfalfa hay, moreover, in a higher carotene content. Carotene i the precursor of Vitamin A, an es ential feed constituent to animals. By increasing the carotene in the feed one may increase the carotene content in the milk (2). Carotene values in stored roughage tend to decline with time in storage. The same may be expected of pelleted forms. Table 2 hows what might be anticipated in decline of carotene value of alfalfa (7). TABLE 2-lnfluence of preserving methods on carotene values of alfalfa Feed Microgram per gram Percent Fresh alfalfa Artificially dried alfalfa (fresh) Alfalfa silage (green) Barn-cured alfalfa Field-cured alfalfa 14 4 The rapid drop in carotene values from the ire h to the field-cured alfalfa repre ent the expected decline in carotene. Pellets when stored will likewise decline ( ee Table 4). Carotene values will decline little in ab ence of air, as hown by the high value given to alfalfa ilage in Table 2. To learn more of the use of dehydrated alfalfa pellets in the grain mixture for dairy cow and heifer in yorning, the gricultural Experiment tation conducted experiments from 1949 to R ults reported here should be of value to dairymen who contemplate u ing pellets in the grain mixture. METHOD Cow OF PROCEDURE in Milk In fall 1949, HoI tein and Guern ey cow divided into three group were fed alfalfa hay and unflower ilage in an outside hay bunk. All cows were fed at milking time twice daily at the rate of 1 pound of orne concentrate to 3 pound of milk. In each case thi concentrate contained 15 percent crude protein. Group I received a mixture containing 20 percent

5 dehydrated alfalfa pellets. Group II received a mixture containing 20 percent dehydrated alfalfa meal. Group III received a mixture containing no alfalfa pellets or meal. In fall 1950, the procedure and the rations were the same except that no group received the dehydrated alfalfa meal. Table 3 shows the grain mixture used for the 3 group. TABLE 3-Rations used in alfalfa-pellet experiments Ration Pellet or meal Control pounds pounds Rolled oats Rolled barley Wheat bran Dried beet pulp oybean meal 80 0 Bone meal ait Alfalfa pellets or meal 250 Total hatch All groups were fed the same ration throughout the winter. Blood and milk sample were taken from. each cow at beginning and end of the experiment of 180 days' duration. ample of the roughages were analyzed at intervals for protein and carotene. Carotene and vitamin-a analyses of the milk of each cow were made at beginning and end of the experiment. RESULTS Roughage Analyses TABLE 4-Carotene ses of roughage during ix months' storage A received at farm Months in storage o Micrograms p r gram after 6 month torage Mal percent Dehydrated chopped hay Alfalfa Baled Bal d lh" %" alfalfa native pellet pellets hay hay Micrograms per gram percent percent percent percent percent Table 4 hows that the relative e of dehydrated hay, meal, and pellets during ix months' storage were very imilar, and no great differen e wa noted in the carotene valu when the e alfalfa produc were received at the farm. However, baled alfalfa when received contained 1 s than one-half the carotene value of the pellets, and the carotene values of the baled hay declined at greater rate. Baled native hay when received con- -5-

6 tained about one-half the carotene values of baled alfalfa hay, yet the native hay lost practically no values during three months' storage. Palatability of the Pellets The 1,4-inch pellets were more palatable than the lh inch pellets for cows in milk. The cows showed tendency to sort out the lh-inch pellet and leave it uneaten. Carotene Content of the Blood Table 5 summarizes two years' analyses of carotene m the blood at beginning and end of the experiment. TABLE 5-CaJ:otene content of the blood of milk cows Number Year of head Ration o pellets o pellets Pellet Pellet Meal Carotene Carotene Carotene in October in April difference microgram/loo ml, microgram/loo ml. microgram/loo ml, There wa less loss of carotene in the blood when an alfalfa supplement was included in the grain rations. Between October 1949 and April 1950 there was a loss of micrograms carotene per 0 mi. of blood in the control ration and only micrograms loss when pellet were included. A year later there was a loss of 20.7 microgram of carotene in the control group compared with a gain of 16.8 micrograms in the pellet group. In the first year one group received dehydrated meal. The blood carotene decrea ed microararn per 0 mi. compared with a drop of micrograms when no meal was included in the ration. Carotene and Vitamin A Content of the Milk Table 6 shows a trend toward increa e in international units per 0 mi. of milk and per gram of fat as the 2-year trial progre ed in the control, the meal, and the pellet group. However the increase wa greater when the meal and the pellets were included in the ration. The one exception wa in the milk of the pellet group in , when the increa e wa.2 LU. per 0 ml, of milk compared with for the control group. For all practi al purposes the differences noted here have no value. Effect on Milk Yield Table 7 ummarizes the decline in milk yields during the 140.day period on the experimental ration for and

7 TABLE 6-Vitamin-A content (If milk during period of October 1949 to April 1951 in terms of International Units Change in LU./ LU./ LU./ I.U./ LU. per Number 0 m!' gram 0 ml. gram 0 m!' gram Ration of head Month milk of fat Month milk of fat milk of fat Control 6 Oct. ' April ' l Alfalfa meal 7 Oct. ' April ' Alfalfa pellets 8 Oct. '49 ILl 2.73 April ' Control 9 Oct. ' April ' Alfalfa pellets 11 Oct. ' April ' The control group and the meal group were each divided at tart of the experiment according to initial milk flow, ince there was wide variation within each group. Percentage decline ranged from 29.8 to 26.7 in the control group, from 36.0 to 32.1 in thepellet group, and from 32.3 to 29.1 in the meal group, the results thus showing greater decline with the supplemented groups. TABLE 7-Becline in daily milk yield on experiment rations fed 140 days Year umber of cows Ration Effect of Dehydrated Control Control Control Pellets Pellets Meal Meal Daily production First Last week week Decline pounds pounds percent Alfalfa Pellets on Growth of Holstein Yearlings; Method (If Procedure During the winter of and , 19 HoI tein yearling were fed on Wyoming native hay ad lib., in a corral hay bunk. Eight of the e received 24 pound daily of dehydrated alfalfa pellets in a grain bunk or an average of 3 pounds of the pellets per head per day. The remaining 11 head, kept in a eparate corral, received an average of 3 pounds of rolled barley per head per day. cale weights were taken for three con ecutive day at beginning and end of the winter feeding period; the mean weight wa u ed in calculation of gain. Comparison of the average daily gain of each heifer wa made with the yorning Agricultural Experiment tation "normal" for heifers of the same age. Table 8 ummarizes re ults. -7-

8 TABLE 8-Average gain of Holstein yearlings compared with normal gain when wintered on native hay and fed either a 3-pound daily supplement of dehydrated alfalfa pellets or 3 pounds of rolled barley Average Average Normal Number days Beginning End Total daily average Group of head on feed weight weight gain gain daily gain pounds pounds pounds pounds pounds Pellet Barley Table 8 indicates that the pellet group gained at subnormal rate, while the gain of the barley group was above normal rate. The barley group gained 1.34 pounds daily as compared with 1.05 pounds daily for the pellet group. PRACTICAL APPLICATION Since cows in milk declined in milk flow on the alfalfa-pellet mixed ration more than on a straight-run mixed ration; since yearling heifers made less gain in weight on alfalfa pellets than on rolled barley during the winter months; and since the carotene and vitamin-a values of the blood and milk were not altered appreciably-it may be concluded that feeding dehydrated alfalfa pellets as a concentrate to dairy cattle becomes an economic problem, to be dealt with in terms of cost of total dige tible nutrients as well as labor aving in handling. Any conclu ions reached as re ult of these experiments must take into consideration the fact that the rations for cows in milk were already high in carotene before the addition of dehydrated alfalfa pellets or meal to the ration. If the control ration had been deficient in carotene, addition of the pellets might have altered the results considerably. LITERATURE CITED (1) Blo er, T. H., F. R. Murdock, R. E. Erb, and A. O. haw The Effect of Physical State on the Utilization of Dehydrated Alfalfa. J our. Dairy ci. 34:492. (2) Hodgson, R. K, H. G. Wi eman, and W. A. Turner More Vitamin A in Milk. U. S. D. A. Yearbook, , pp (3) Hope, E. B. R. E. Erb, T. H. Blo ser, U.. Ashworth, and A. O. haw The U e of Dehydrated Forages in Dairy Cattle: I. Grain ubstitution with Finely Ground Material. Jour. Dairy ci. 33: (4) 1orrison, F. B Feed and Feeding, 21st ed., p. 86. Morrison Publishing Co., Ithaca,. Y. (5) Murdock, F. R.. L. Miller, T. H. BIos er, and R. E. Erb The Composition and utritive Value of Alfalfa Hay Prepared by Three Methods of Curing and in Three Physical tat. Proc. 32nd An. 1eet., Western Div., Amer. Dairy ci. A o. fontana tate College, July. (6) Petersen, W. E Dairy cience, 2nd ed., p Lippincott Co., ew York. (7) Wi eman, H. G., et al The Carotene Content of 1arket Hay and Corn ilage. Jour. Agr. Res. 57 : &-