n4 xl A. & M. COLLEGE 6:5 TE TEXAS AGRICULTURAL EXPERIMENT STATION A. B. CONNER, DIRECTOR, College Station, Texas BULLETIN NO. 658 AUGUST 1944 DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS O. C. COPELAND AND C. N. SHEPARDSON Division of Dairy Husbandry AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS GIBB GILCHRIST, President E06-844-4M-L180 [Blank Page in Original Bulletin] Dried citrus peel and pulp proved a satisfactory car- bonaceous feed for milk cows when used as fifty per cent of the concentrate mixture. In five separate experiments, citrus peel and pulp yielded an average of 74 therms per hundred pounds. Citrus peel and pulp was found to be a palatable feed except when used in large quantities. No noticeable effects upon the flavor and aroma of milk could be detected as the result of feeding citrus peel and pulp. Neither did the use of this feed in the dairy ration result in extreme scouring. C 0 N T E N T S PA Introduction . . . . . . . . . . . . . . —. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Plan of Investigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. '7; l Feeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. l‘ Experimental Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Liveweights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ye Milk Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l Changes in Liveweights ......... . . . . . . . . . . . . . . . . . . . . . 12; Results of Feed Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Productive Energy of Citrus Pulp . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1d Discussion . . . . . . . . If . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1 Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1 DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS O. C. Copelandl and C. N. Shepardsoni’ As a by-product of the citrus industry located in the lower Rio Grande "Valley of Texas, there are considerable quantities of dehydrated citrus peel and pulp available as a feed for livestock. Since the dehydration plant was constructed in 1938, the production of citrus peel and pulp has averaged about 6,320 tons annually. The producers of citrus peel Sand pulp estimate that approximately 85% of this feedstuff is composed of the peel, rag and seed of grapefruit and about 15% composed of the A use from oranges. Before the machinery was installed for the de- ydration of this material, representatives of the industry contacted livestock men at the College relative to conducting feeding experiments ‘ th this product both to beef cattle and milk cows. Much of the citrus itsed in the feeding tests reported here was donated for experimental rposes to the Division of Dairy Husbandry by the Rio Grande Valley trus Exchange. Probably due to the fact that the production of citrus peel and pulp limited to three general areas of the country, our knowledge con- ing its feeding value was somewhat limited. California, Florida and exas are the only sections where citrus is produced in sufficient quantities permit the production of a feedstuff as a by-product of the citrus ustry and in suflicient quantities to warrant the installation of de- p ration machinery. Workers at the California Station (6) found that ‘ed orange pulp showed to be equivalent to beet pulp for milk produc- a» . Jones, et al., (3) at the Texas Station reported dried citrus pulp “d ear corn chops with husk about .equal in feeding value as to gains i, liveweight when not more than 25% of the concentrates was com- of dried citrus pulp. However, the degree of finish was superior A ithe group fed ground ear corn. When dried citrus pulp was used as o of the concentrate mixture the feed was less palatable, had slightly liter laxative eifect, and gains and degree of finish were not so ftisfactory as with the ear corn chops. Neal, et al., (5) at the Florida tion found both grapefruit and orange refuse a satisfactory carbo- idrate feed for beef cattle. They report both of these feeds to be table and to produce a glossy coat of hair and satisfactory gains. f some later work by the same authors (1), dried grapefruit pulp was n’ to dairy cattle and yielded 1.2% digestible protein and 76% total estible nutrients. When compared with beet pulp slightly more milk Hf» butterfat was produced from the cows fed grapefruit pulp than from pa C. Copeland, Chief, Division of Dairy Husbandry, Texas Agricultural Experiment 1 011. . . N. Shepardson, Head, Department of Dairy Husbandry, Agricultural and Mechanical ~ of Texas. fed beet pulp. They concluded that these two by-products are TABLE 1. Chemical Analysis of Feeds Used* Nitrogcn- Units ' Phos- Crude Fat Crude free Water Ash crude Lime phoric Feed Protein fiber extract carotene acid per gram Per cent Per cent Per cent Per cent Per cent Per cent Per cent Per cent ‘Dried citrus pulp . . . . . . . . . . . . . . . .. 5.50 1.71 10.21 63.48 13.23 l 5.87 0.35 . . . . . . . . . . . . . . . . . . .. Dried citrus pulp** . . . . . . . . . . . . . .. ".41 1.81 10.33 66.88 8.41 7.16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Corn and cob meal................ 9.01 “$.13 7.83 68.70 9.70 1.63 . . . . . . . . .. 0.08 0.43 Cottonseed meal . . . . . . . . . . . . . . . . .. 43.48 6.16 10.28 25.57 8.66 5.85 . . . . . . . . .. 0.27 2.28 Ground whole oats . . . . . . . . . . . . . . .. 8.94 5.46 11.79 58.92 11.00 3.89 . . . . . . . . .. 0.18 0.66, Wheatlbran . . . . . . . . . . . . . . . . . . . . .. 17.80 4.14 9.41 53.70 8.63 6.32 . . . . . . . . .. 0.25 2.81 Alfalfa hay . . . . . . . . . . . . . . . . . . . . . .. 18.58 1.74 27.27 34.20 8.27 9.94 3.90 1.80 0.66 Ground limestone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53.65 . . . . . . . . . . *Analysis made under the direction 0f_G. _ **Average analysis given in Texas Station Bulletin No. 620 Fraps, Divisio n of Chemistry. 9 W S E‘ I5 Z Z 9 a: U‘ 9° v-i Ed N l> m > Q FU l-l O C! F‘ H G FU > t" E11 >4 “U F] E’. E Z *8 U2 G > E C Z DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS 7 _ fctically equal in feeding value when supplied as bulky carbohydrate .. to dairy cows. They also were not able to find any characteristic (or in the milk as a result of feeding dried grapefruit pulp which f‘ d be attributed to the feed. Morrison’s Feeding Standard (4) shows the average composition of dried grapefruit refuse, orange pulp l beet pulp are very similar. The grapefruit refuse is somewhat lower A digestible protein than any of the other feeds but is slightly higher itrogen free extract. p lthough considerable quantities of beet pulp are fed to dairy cattle gthis/ State, most of it is utilized in the mixed feed business. Utilizing ‘b ~pulp in this manner does not afford dairy feeders much knowledge if”- its nutritive value as a feed for milking cows. Since the ilable information from both the Florida and California Stations re comparisons of citrus peel and pulp with beet pulp, it was decided lconduct this investigation comparing citrus peel and pulp with corn and if. meal, a feed with which all dairymen are well acquainted as to its merits milk production. The chemical analysis of citrus peel and pulp and p and cob meal (without shuck) are also very similar except that corn and cob meal is considerably higher in protein. The chemical ‘lyses of the feeds used in the experiments are shown in Table 1. PLAN OF INVESTIGATION A oth the dairy herds of the Experiment Station and the Dairy De- j ment of the School of Agriculture were used to conduct five separate riments comparing citrus peel and pulp with corn and cob meal as chief carbohydrate feed in the concentrate ration for lactating cows. double-reversal method of feeding was used. In this method cows A - paired so that each pair was as nearly alike as possible as to size, of lactation, age and milk producing ability based on previous A tions. One cow from each pair was placed in group A and her mate oup B. Group A was started on the corn and cob meal and group ‘pas started on the citrus ration. Each experiment was conducted over ‘p’! day period. At the end of the first 30-day period the feeds for the groups of cows were switched so that group A received the ex- ental ration of citrus peel and pulp and group B was fed the ground corn ration. Then at the end of the 30 days the groups were - hed back to the same feeds they received at the beginning of the jriment. These three 30-day periods constituted one experiment. The F 10 days of each 30-day period was considered preliminary and the '_~ ts discarded and the last 20 days considered experimental. In the riments conducted with the Experiment Station dairy herd, the i - were fed in dry lot. In the experiments conducted by the Dairy bandry Department, the cows were not fed in dry lot but were al- it access to pasturage and carbonaceous hay was fed to each group choice. 8 BULLETIN NO. 658, TEXAS AGRICULTURAL EXPERIMENT STATION Feeds All concentrates fed to cows both at the Station dairy and Department of Dairy Husbandry were fed in the milking barn. The rate of grain: feeding was in accordance with milk production, usually about one .0 pound of grain for each two and one-half pounds milk produced per» cow daily. Alfalfa hay was used as a roughage with the Experiment‘ Station herd and was fed twice daily in a shed equipped with individual feeding mangers separate from the milking barn. Sorghum and Sudan!" grass hay were fed free choice to cows on experiment at the Dairy, Husbandry Department. The grain mixture used at the Experimen Station is shown in Table 2 and the grain mixture used by the Department?’ of Dairy Husbandry is shown in Table 2A. Table 2. Experimental Concentrate Feeds in Pounds (Experiment Station Herd) Feeds (clgllinmaera? Ctiiildlspglerfl concentrate concentrate g mixture mixture ' Citrus peel and pulp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . .. 0.0 50.0 Corn and cob meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 50.0 0.0 Cottonseed meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.0 25.0 Ground oats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..' . . . . . . . .. 10.0 10.0 \Vheat bran . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.0 12.0 Oyster shell flour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.0 2.0 Salt . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l .0 1 .0 Table 2A. Experimental Concentrate Feeds in Pounds (Dairy Husbandry Department Herd) Corn and Citrus peel Feeds cgggerlirtfifiie cgiilgeritiillte ~. mixture mixture F Citrus peel and pulp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.0 50.0 Corn and cob meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 50.0 0.0 Cottonseed meal._ . . . . . . . . . . . . . . . . . . _ . . . . . . . . . . . . . . . . . . . 31.0 31.0 _ Ground oats...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 8.0 8.0 ’ ' Wheat bran . . . . . . . _ . . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . . . . . . 8.0 8.0 Oyster shell flour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.0 2.0 Salt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l .0 1 .0 DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS 9 Experimental Animals In three tests conducted at the Experiment Station dairy, purebred tJersey cows were used in all experiments. In the first experiment there < .719 +0.64 +0.46 +0.81 +0 5s -0.25 -0.18“ Alfalfa hay X .436 +4.25 +1.85 _ +2.59 +1 13 +9.31 +4.06 "- Milk X .30 —11.67 -—3.50 -30.19 —9.06 —10.01 —-3.00 Productive _ energy of citrus J peel and pulp . . . . . . . . . . . . . . . . . . . . +9439 . . . . . . . . . +101.28 . . . . . . . . . +8654 *1 Productive energy per 100 lbs. citrus peel and pulp. . . .. . . . . . . . . . . . 76.95 . . . . . . . . . 73.04 . . . . . . . .. 74.12 Table 6A. (From Equations in Table 5) Dairy Department Calculation of Productive Value of Citrus Peel and Pulp in Therms Experiment 1 Experiment 2 Productive energy Productive Productive Pounds value Pounds value Citrus . . . . . . . . . . . . . . . . . . . . . . . . . . .. 132.00 . . . . . . . . . . .. 138.64 . . . . . . . . . . . . .. Corn and cob meal X .747 . . . . . .. +131.3O +98.08 +139.14 +103.94 Cottonseed meal X .720 . . . . . .. —0.44 -0.32 +0.25 +0.18 Wheat bran X .563 . . . . . .. —0.12 —0.07 +0.10 +0.06 Cats X .719 . . . . . .. —-0.12 ——0.09 +0.10 +0.07 Milk X .30 . . . . . . .. -9.02 —2.71 +4.22 +1.27 Productive energy of citrus peel and pulp... . . . . . . . . . . .. +£14.89 . . . . . . . . . . .. +105.52 Productive ' energy per 100 lbs. citrus peel and pulp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71.89 . . . . . . . . . . .. 76.11 DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS 15 Productive Energy of Citrus Pulp The.value of a carbohydrate feed for milk cows is measured by de- _, ining the productive energy content. The productive energy value " a feed is measured from the results of differences in milk production, l,» consumption and changes in liveweights for the various periods cows were fed the experimental feed as compared with the check Ton. Because different feedstuffs and milk each have different energy ues, these items have been reduced to a common term “productive irgy.” In the analysis of these data, the productive energy of the Q» was calculated by the Division of Chemistry as illustrated in r as Station bulletin 461 (2). The calculated productive energy of the r?» used in the corn and cob meal ration was multiplied by the pounds gfeach feed to obtain the total productive energy supplied by the corn y cob meal ration. Similar calculations were made for differences ti‘ milk production. These differences in productive energy were added or subtracted from the productive energy contained in the corn and meal used. The remainder of productive energy was divided by the pounds of citrus fed to obtain the productive value forithe citrus gessed as “therms per hundred pounds” as shown in Tables 6 and 6A. previously mentioned, the results of changes“ in liveweights were included in these calculations because of such wide variations in the “ults of liveweight changes between the three experiments conducted the Experiment Station. It is believed that the productive energy yes calculated from the differences in milk production and feed con- ‘ption more nearly represent the true value of citrus peel and pulp use of the extreme variations in liveweights between the. three riments. .5‘ DISCUSSION pesults of the effects of feeding citrus peel and pulp in the dairy centrate mixture using 50% of the entire concentrate mixture as . s pulp as compared with a similar ration containing corn and cob p- without shuck are presented for five separate experiments. It can ilseen from Table 4 that in each experiment except the second ex- lent conducted by the Dairy Husbandry Department there was a ‘ht difference in milk production favoring the corn ration. The average irence per cow per day when the results of production for both ‘ups were combined was .86 lbs. per day. The same difference Ymilk production for the two experiments conducted by the De- “ment of Dairy Husbandry was .12 lbs. per cow daily. Both of a - average differences in milk production were in favor of the corn L cob meal ration over the citrus pulp ration. However, these dif- inces are so small they cannot be considered as significant. This ‘i sents fairly close agreement as to the effects of citrus pulp on yields in dairy cows as compared with a ration of corn and cob meal. j milk‘ cows than when the changes in liveweights were included* 16 BULLETIN NO. 658, TEXAS AGRICULTURAL EXPERIMENT STATION The average differences in gains or losses in liveweights between the periods of feeding corn and cob meal as against citrus peel and pulp in the same group of cows as well as between groups for the three ex- periments showed an average difference in weight of .30 lbs. per cow "daily in favor of the corn and cob meal. There was such variation in the results of liveweight changes between the three experiments that this difference of .30 lbs. per cow daily is not significant even though the differences representing gains in each of the three experiments were in favor of the corn and cob meal ration. Since some investigations have indicated that citrus sometimes caused excessive scouring, all experimental animals were kept under close observation. During the progress of all of these experiments, no extreme laxative condition developed in any of the experiment animals. General thrift was also very similar between the cows fed the citrus peel and pulp as compared to those fed the corn and cob meal. It was our observation that cows fed the citrus ration did show more gloss to their hair even though the feeding periods were comparatively short. We were not able to determine any effects on the flavor and aroma of the milk as the result of feeding citrus. It can be stated that the citrus proved to be palatable even _when fed as 50% of the entire concentrate mixture except in cases when fed to the higher producing cows consuming large quantities of feed. There was some refusal although slight in cows con- suming 16 lbs. of concentrates daily which represents a consumption of 8 lbs. of citrus. Corn and cob meal without shuck was used in these experiments as the check for the citrus feed because it was quite similar in chemical composition although the corn and cob meal was somewhat higher in digestible protein than was the citrus peel and pulp. No allowances were made for this difference through adjustments in the amounts of high protein feeds used in the grain mixtures because it was calculated in formulating the grain rations to be used that ample protein was available in both feeds. It was assumed that any excess protein furnished by either ration could be utilized for energy purposes. In Tables 6 and 6A giving the calculations of the productive value of citrus peel and pulp in therms as determined from the results of milk production and feed consumption shows that the two feeds are almost identical as to their productive energy values. The results as given in these Tables show the productive energy value of corn and cob meal and citrus peel and pulp to be almost exactly the same. The productive energy for corn and cob meal is 74.7 therms per hundred pounds as compared to an average for the five experiments of 74.42 therms per hundred pounds of citrus peel and pulp. This average does not include calculations based on differences in liveweight changes because they did not appear to be of significance and also because liveweight changes were not taken in the two experiments conducted by the Dairy Husbandry Department. Since slightly more milk was produced as a result of feeding the corn and cob meal as compared with the citrus peel and pulp although the \ DRIED CITRUS PEEL AND PULP AS A FEED FOR LACTATING COWS 17 uctive energy values of the two feeds as shown by these results ere almost identical, the differences in production favoring corn and b meal must have been due to the extra amount of feed consumed the cows while being fed the corn and cob meal ration. This verifies previous statement that the citrus pulp was not quite as palatable ’ the corn in the higher producing cows which consumed large quantities ; concentrates. These experiments represent a rather critical test for s pulp because of the high percentage which was used in the con- trate mixture. Where such favorable results were obtained using large quantities as reported in these experiments, it can safely be n’, med that equally good results would be obtained if smaller amounts ‘e used; that is, 25% of the entire grain mixture instead of 50%. future work we plan to use smaller quantities and conduct some ex- g ments comparing citrus peel and pulp with beet pulp; however, since beginning of the War, we have been unable to secure citrus some he time and have never been ableto obtain beet pulp. CONCLUSIONS ve experiments have been conducted with lactating dairy cows com- g a concentrate ration containing 50% citrus peel and pulp with i? ilar concentrate ration containing 50% ground corn and cob meal i, out shuck. =_='4- results of milk production and changes in liveweights show a k- diiference favoring the ground corn ration. e productive energy value of citrus peel and pulp as calculated l the results of these five experiments showed an average of 74.42 fs per hundred pounds as compared with 74.7 therms for corn and l‘ eal. s peel and pulp when fed in moderate quantities proved to be alatable as corn and cob meal. In extremely hot weather citrus {and pulp when fed in moderate quantities has a beneficial effect lthe appetite of dairy cows. It seemed that the citrus ration did V "a slight effect upon the degree of glossiness in the coat of hair. fwere not able to detect any noticeable effect upon the flavor and of the milk produced by cows fed as much as 8 lbs. daily of a peel and pulp. Even when fed in large quantities, it did not produce _ eme laxative condition to the cows. , LITERATURE CITED Told, P. T. Dix, Becker, R. B. and Neal, W. M. 1941. The Feeding Value and _-»- ‘tive Properties of Citrus By-Products. II. Dried Grapefruit Pulp for Milk Pro- ion. Florida Agricultural Experiment Station Bul. 354. .138, G. S. 1932. The Composition and Utilization of Texas Feeding Stuffs. Texas "cultural Experiment Station Bul. 461. J. M., Hall, R. A., Neal, E. M. and Jones, J. H. 1942. Dried Citrus. Pulp in p‘ Cattle Fattening Rations. Texas Agricultural Experiment Station Bul. 613. » Ion, F. B. 1936. Feeds and Feeding, 20th Edition. W. M., Becker, R. B. and Arnold, P. T. Dix. 1935. The Feeding Value and - tgve Properties of Citrus By-Products. Florida Agricultural Experiment Station. i 2 5. l, n, W. M. and Meade, S. W. 1927. The Value of Orange Pulp for Milk Produc- California Agricultural Experiment Station Bul. 427. ‘