The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
Bulletin 751 C March 1972
for Beef Cattle
H. L. Chapman, Jr., C. B. Ammerman,
F. S. Baker, Jr., J. F. Hentges,
B. W. Hayes, and T. J. Cunha
Florida Agricultural Experiment Stations
Institute of Food and Agricultural Sciences
S' r University of Florida, Gainesville
J. W. Sites, Dean for Research
00 o o 0 .@
.0 ** *0* 0 0
00000.* @0 0
Introduction .................................------ 3
Types of citrus feeds ..........------.......----------------- 4
Dried citrus pulp .......... --------.........------------- 4
Physical characteristics and nutrient composition ........ ....---------- 5
Feeding value of dried citrus pulp ............................. 8
Feeding value in drylot -.................. ..-.... ...- ---.. 9
Feeding value on pasture ............... ------------..------- 9
Feeding pelleted citrus pulp .................. .---------------- 10
Feeding recommendations ............. .--------------..------ 13
Dried citrus meal .--.......... -------.--------------------- 13
Feeding value of dried citrus meal -----............--... --------- -- 14
Feeding recommendations ...... .-----...............--------. 15
Citrus seed meal ........---------- .---------------------- 15
Feeding value of citrus seed meal ............... .----------------- 16
Feeding recommendations ....-........------------- -.---------16
Citrus molasses .......................-------..--------------------- 16
Comparative composition of citrus and blackstrap molasses ..----........ 17
Feeding value in the feedlot ...- -----...-------......- -.---.----- 18
Feeding recommendations for feedlot cattle ...............----------.. -------. 19
Feeding value on pasture .......-----..---...----- ----...---------- 20
Feeding recommendations for pasture cattle .......-.....----.. ------------ 20
Wet citrus pulp .-..- -.---..--... ----....-------.-------------- 20
Fresh wet citrus pulp ...---........------..----- -----.-- --- ---- 21
Wet citrus pulp silage .....-- -----........ ---- --------- 22
Feeding recommendations .......----....--------------------- 23
Summary and discussion ............ ---.--... --.------ ---- ----- 24
Literature cited ..... .--...----- ..---...----------.. ..----. ------.. ----- -26
Appendix A --- .--- --------------------29
Appendix B ........----...-----..... .. ------------- 30-------0
Acknowledgements ........................---------- 34
This publication provides a summary of research from the Florida
Agricultural Experiment Stations concerning the use of citrus feeds in
cattle rations. The information is presented for beef cattlemen and the
CITRUS FEEDS FOR BEEF CATTLE
H. L. Chapman, Jr., C. B. Ammerman, F. S. Baker, Jr.
J. F. Hentges, B. W. Hayes, and T. J. Cunha1
A number of residue materials are produced when fresh citrus
is processed into juice, concentrate, and canned fruit. These in-
clude peel, rag, and seeds. The volume of these residue materials
has increased as the Florida citrus industry has grown (37)2.
Studies have been conducted by researchers of the Florida Agri-
cultural Experiment Stations for 60 years3 (15, 30, 38) to eval-
uate the various materials as feeds for livestock. Early work
emphasized the use of fresh citrus pulp for livestock feeds (36),
and for the first few decades considerable quantities of this
.material were dumped on the ground and fed wet to cattle as a
supplement to pasture, range, and dairy feeds. The high mois-
ture content of the fresh pulp limited the distance it could be
economically transported, and there were variations in palata-
bility of pulp from various citrus fruits (10, 14). These prob-
lems led to the development of dried citrus pulp during the
1930's, and today most citrus pulp is used in the dry form. When
the citrus pulp is dried, other citrus feeds such as molasses and
citrus meal are produced.
The chemical composition and physical appearance of these
citrus feeds varies a great deal, depending on the kind of citrus
fruit being processed and the procedures used at various proc-
essing plants. For example, some citrus pulp will have the juice
pressed out before drying and some will be dried without this
being done; some pulp contains considerable seeds and some
very little seed; and some will have more fine particles than
others. These factors emphasize the differences that may occur
between citrus pulp and the importance of properly evaluating
the material being fed. In addition, citrus pulp is often pelleted
SCenter Director, Agricultural Research Center, Ona; Associate Animal
Nutritionist, University of Florida, Gainesville; Animal Husbandman,
Agricultural Research and Education Center, Quincy; Animal Nutrition-
ist, University of Florida, Gainesville; Assistant Animal Nutritionist,
Agricultural Research and Education Center, Belle Glade; and Animal
Nutritionist and Chairman, Animal Science Department, Gainesville.
" Numbers in parentheses refer to Literature Cited.
"Becker, R. B. 1969. Personal communication.
to reduce hauling and storage costs, and this has brought about
another important change in processing citrus by-products.
Approximately 672,000 tons of citrus by-product feeds were
produced in Florida during 1969-70 (37). This included about
588,000 tons of dried citrus pulp, 68,000 tons of citrus molasses,
and 16,000 tons of dried citrus meal. These feeds provide the
Florida beef cattleman with excellent sources of high energy
feeds for beef cattle rations. The purpose of this bulletin is to
summarize current knowledge and recommendations for the use
of these materials in beef cattle feeding.
TYPES OF CITRUS FEEDS
Citrus feeds include dried citrus pulp, citrus molasses, citrus
meal, citrus seed meal, and wet citrus pulp. The relationship
of the various feeds is presented in Figure 1. Considerable
variation may occur in citrus feeds, and it is very important to
properly evaluate the material being fed. The types of citrus
by-product feeds are listed in Table 1 in order to indicate some
of the variations that may occur. Detailed information about
more descriptive nomenclature for citrus by-products and a
glossary of feed terms are presented in Appendix A and B.
Table 1.-Types of citrus feeds.1,2
Citrus residue, fresh, not pressed, ensiled or not ensiled
Citrus residue, fresh, pressed, ensiled or not ensiled
Citrus residue, not pressed, dehydrated, with fines
Citrus residue, pressed, dehydrated with fines
Citrus residue, not pressed, dehydrated, without fines
Citrus residue, pressed, dehydrated, without fines
Citrus residue, not pressed, dehydrated, with pelleted fines added
Citrus residue, pressed, dehydrated, pelleted fines and molasses added
Dried citrus pulp fines, from pressed citrus residue
Dried citrus pulp fines, from non-pressed citrus residue
Citrus seed meal
Citrus mill dust
1 Feeds in this list, except for citrus seed meal and citrus molasses, will occur
with and without seed.
"2 All of the dried citrus products may be sold in pelleted or non-pelleted form.
DRIED CITRUS PULP
Research at the Florida Agricultural Experiment Stations
in 1911 suggested that dried citrus pulp had potential value as
a feed for cattle (15, 38). During the early 1930's dried citrus
pulp began to be produced commercially and since then has be-
(Ground or chopped)
Citrus Dehydrated without pressing Dried
seeds Ca(OH) added citrus pulp
liquor fresh pulp
Citrus Dried Dried
molasses citrus pulp Sieved citrus
(without molasses) meal
oils seed Added back to
Dried pulp Pelleted Sold as
Sold Dried back to meal
as citrus pulp
Figure 1.-Schematic presentation of citrus by-products.
come an important feedstuff in cattle rations. It has been esti-
mated that approximately 20% of the annual production of pulp
is fed to beef cattle and 80% to dairy cattle. Greater quantities
of pulp will become available for feeding beef cattle if predicted
increases in citrus production occur.
Physical Characteristics and Nutrient Composition
Dried citrus pulp is comprised primarily of grapefruit and
oranges, but may also contain the residue of lemons, limes, and
tangerines. As shown in Figure 1, the basic procedure for pro-
ducing dried citrus pulp consists of grinding or chopping and
then dehydrating the fresh fruit residue. The residue may be
pressed, to remove the press liquor, and the remaining pulp then
dried; or, it may be dried without removing the press liquor.
If it is pressed, molasses is produced from the press liquor.
Molasses is sometimes added back to the pulp during the drying
process. The finer particles of the dried pulp are often removed
by sieving and either sold as citrus meal or pelleted and added
back to the pulp. The pulp may or may not contain large amounts
of seeds. These differences in processing, in source and variety
of fruit, and in type of canning operation from which the fruit
residue is obtained, are responsible for the variation that may
occur in the physical characteristics and nutrient content of
dried citrus pulp.
The physical characteristics of 24 commercial samples of
dried citrus pulp collected in mid-season are shown in Table 2.
The average density (weight of a cubic foot of pulp) for all
samples was 18.70 pounds. Each sample was separated into two
fractions using a Number 10 sieve. The material that passed
through the sieve was approximately equivalent to commercial
citrus meal. The fraction retained by the sieve was separated
further into pellets, seeds, and peel plus pulp. The pulps con-
tained an average of 45.63% of fine and 54.37%o coarse material.
As shown in Table 2, considerable variation existed in the
amounts of peel, pulp, seeds, and pellets.
The average nutrient composition of the component fractions
of citrus pulp is shown in Table 3. Seeds were considerably
higher in protein and ether extract and lower in ash, crude fiber,
and nitrogen-free extract than the other fractions. The pelleted
and unpelleted fines were higher in calcium, phosphorus, ether
extract, and protein than was the peel plus pulp fraction.
Table 2.-Physical characteristics of 24 dried citrus pulp samples (2).1
Characteristic Average Range
Density, Ib/cu ft. 18.70 12.54 22.66
Unpelleted fines, % 40.31 9.45 64.80
Pelleted fines, %8 5.32 3.40 38.61
Peel plus pulp, % 49.62 28.50 68.71
Seeds, % 4.75 1.83 8.27
1All values obtained on citrus pulp samples under air-dry conditions.
2 Dried citrus pulp was separated using U.S. Bureau of Standards No. 10 sieve.
Approximately equivalent to citrus meal. Although pellets were retained, they
were considered as part of the material that would pass through a No. 10
8 Only 8 of 24 samples examined contained pellets. The average pellet content
of the 8 samples was 15.96.
Table 3.-Average nutrient composition of dried citrus pulp fractions
Fine material Coarse material
Nutrient Unpelleted Pelleted pulp Seeds
Ash 6.55 7.69 5.09 2.97
Ether extract 2.14 2.13 1.78 47.96
Crude protein 7.16 7.44 6.50 17.31
Crude fiber 12.58 12.91 13.79 8.06
Nitrogen-free extract 71.57 69.83 72.84 23.70
Calcium 2.36 2.37 1.68 0.57
Phosphorus 0.11 0.13 0.09 0.30
SValues expressed on a dry matter basis. Each figure is the average of 24
samples except for the pelleted fines. Only 8 of the 24 samples contained
The average nutrient composition of 1728 citrus pulp sam-
ples, analyzed over a 5-year period, is shown in Table 4. The
moisture content of the pulp varied from 3.5 to 13.7% with an
average of 8.58%. Expressed on an air-dry basis, the citrus
pulps had an average of 6.16% crude protein, 12.28% crude
Table 4.-Average nutrient composition of dried citrus pulp (4).1,2
Nutrient analyzed Content
Moisture, % 1728 8.58
Ash, % 1728 4.68
Ether extract, % 1728 3.74
Crude protein, % 1728 6.16
Crude fiber, % 1728 12.28
N.F.E., % 1728 64.56
Calcium, % 82 1.43
Phosphorus, % 82 0.11
Magnesium, % 82 0.12
Potassium; % 82 1.09
Sodium, % 82 0.096
Sulfur, % 10 0.066
Iron, ppm 35 98.72
Copper, ppm 35 6.19
Zinc, ppm 35 9.94
Manganese, ppm 35 5.70
Cobalt, ppm 10 0.073
SAnalyses obtained by the Feed Laboratory, Division of Chemistry, Florida
Department of Agriculture, Tallahassee.
2 All mineral values expressed on a dry matter basis.
fiber, 64.56% nitrogen-free-extract (N.F.E.), and 4.6% ash.
Nutrient composition of the pulp varied only slightly from
year to year. Mineral analyses performed on a limited number
of samples (Table 4), indicate that dried citrus pulp is higher
in calcium and potassium than are most grains, but lower in
phosphorus and in micro minerals except for iron.
As mentioned earlier, major factors influencing the nutrient
composition of citrus pulp include amount of seeds and molasses
remaining with the pulp. Citrus pulp with large amounts of
seeds will contain more protein and fat than pulp without seeds,
and citrus pulp from which molasses has been removed will be
higher in fiber and lower in nitrogen-free extract than pulp
that contains molasses.
Feeding Value of Dried Citrus Pulp
Good quality dried citrus pulp is highly palatable. It is
sometimes referred to as a "bulky concentrate feed" since it is
bulky in nature but also relatively high in digestible energy. It
is low in digestible protein and is primarily an energy feedstuff
having certain "roughage properties." These physical and nu-
trient characteristics must be considered when rations with
citrus pulp are formulated. Average coefficients of digestibility
for the nutrients in good quality citrus pulp are: protein,
51%; fat (ether extract), 85%; fiber, 68%; and nitrogen-free
extract, 89%. These values represent determinations obtained
in five studies (1, 8, 25, 31, 34) using different types of animals
and rations, and different citrus pulps. When these data were
applied to the average composition values for pulp (Table 3),
an average total digestible nutrient (TDN) value of 76 was ob-
tained. The TDN value would be lower for poorer quality citrus
pulp. Dried citrus pulp has an estimated net energy value for
full fed finishing cattle of 68 to 73 megacalories per 100 pounds
(32). When fed at levels of no more than 40% of the ration,
good quality citrus pulp is considered to be equal in feeding
value to ground snapped corn and to have a value 85% to, 90%
of that for shelled corn (32).
Extremely high dehydrating temperatures can result in a
dried pulp which is dark in color and which contains consider-
able quantities of charred material. Such pulp is less palatable
and has less nutritional value due to a reduced digestibility of
protein and energy (3).
Table 5.-Average performance of steers fed rations containing citrus
pulp, corn meal, or ground snapped corn (35).1
Citrus snapped Corn
pulp corn Meal
Initial wt., Ib 455 434 434
Final wt., Ib 788 773 769
Daily gain, Ib 2.38 2.42 2.39
Daily ration, Ib
Concentrate2 11.44 12.18 11.43
Pangolagrass hay 3.83 3.61 3.78
Citrus molasses 2.00 2.00 2.00
Minerals 0.14 0.19 0.19
Total 17.41 17.98 17.40
Feed/cwt. gain, Ib 735 743 725
1 Average of three trials of 140 days in drylot.
2 Concentrate contained 70% citrus pulp, corn meal, or ground snapped corn,
5% 3/4 cut alfalfa and 25% cottonseed meal (41% crude protein).
Feeding Value in Drylot
Citrus pulp has compared favorably with corn meal and
ground snapped corn in feedlot rations for yearling steers (35)
when fed at 70% of the concentrate, or 46 % of the total ration.
During later studies various levels of citrus pulp were added
to cattle finishing rations (5,7). Data in Table 6 shows that
steers receiving 22% and 44% of citrus pulp in their rations
gained more than steers receiving no citrus pulp. Steers receiv-
ing citrus pulp also had a higher carcass grade, higher dressing
per cent, and more fat over the ribeye. The ruminal papillae of
those steers fed 22% citrus pulp were normal, but there were
several parakeratotic rumens in the steers fed the two higher
levels of pulp. This condition did not appear to influence the
performance of steers.
Feeding Value on Pasture
Studies have been conducted concerning the use of dried
citrus pulp as a supplement for finishing steers on pasture (19).
Crossbred steers grazing St. Augustine pasture were fed either
Table 6.-Average performance of steers fed different levels of citrus
Level of citrus pulp in
concentrate, % 2
0 22 44 66
Initial wt., Ib 667 685 672 670
Final wt., Ib 974 998 1014 975
Daily gain, lb. 2.92 2.98 3.26 2.90
Daily ration, Ib
Concentrate 22.05 24.78 23.91 20.92
Bermudagrass hay 2.27 2.27 2.25 2.11
Total 24.32 27.05 26.16 23.03
Feed/cwt. gain, Ib 883 908 802 794
1Yearling steers fed 105 days in drylot.
2Citrus pulp replaced an equal amount of corn meal-cob meal mixture (80%
corn meal, 20% cob meal).
ground snapped corn, dried citrus pulp, cane molasses, or citrus
molasses (Table 7, Experiment 1). The steers gained average
of 1.08 to 1.16 pounds per head daily, and the slight differences
between supplements were not significant. In a similar study
(Table 7, Experiment 2) 6 pounds of several different feeds
were fed per head daily to grade Brahman steers grazing St.
Augustine pasture. Those steers fed citrus pulp gained faster
and had a slightly higher dressing per cent than steers fed
Feeding Pelleted Citrus Pulp
There have been economic limitations on the transportation
of dried citrus pulp because of its relative bulkiness. When
pelleted, its bulk is greatly reduced, resulting in a substantial
reduction in transportation and storage costs. Pelleting also
increases handling efficiency, decreases dustiness, and decreases
bridging in storage bins. To determine the nutritional value of
pelleted citrus pulp, an experiment was conducted to compare
the feeding value of pelleted and non-pelleted dried citrus pulp,
fed at different levels to steers in drylot. The experimental de-
sign and results are shown in Table 8. Steers fed the control
rations containing no citrus pulp gained an average of 2.84
pounds daily. Those steers fed the three levels of regular pulp
gained an average of 2.89 pounds and those fed pelleted pulp
gained 2.98 pounds per day. Steers fed 66% regular pulp gained
2.61 pounds and those fed 66% pelleted pulp gained 3.04 pounds
per head daily. Feed intake was greater throughout the feeding
period for those steers fed pelleted pulp. The difference in feed
consumption may have been due in part to the difference in
ration density (weight per cubic foot). The concentrate con-
taining 66% pelleted pulp had a density more than twice that
.of the concentrate containing 66% non-pelleted pulp. Pelleting
the citrus pulp increased its density from 13.0 to 41.6 pounds
per cubic foot. The decrease in bulkiness and particle size may
cause the pelleted pulp to lose some of the "roughage properties"
generally attributed to non-pelleted citrus pulp. Other studies
(24) have suggested that the utilization of urea nitrogen may
be improved by incorporating the urea into a citrus pulp pellet.
More information is needed concerning the effect of pelleting
on nutritional value of citrus pulp.
Table 7.-Average performance of steers fed various supplements on
Roselawn St. Augustine pasture.
Citrus snapped strap Citrus
Experiment 1 (19)' pulp corn molasses molasses
Initial wt., Ib 663 666 656 658
Final wt., Ib 795 808 796 795
Daily gain, Ib 1.08 1.16 1.15 1.12
Supp./cwt gain, Ib 495 549 682 814
Citrus snapped Sugarcane Mixed
Experiment 2 (18)2 None pulp corn molasses feed'
Supp./cwt gain, Ib 0 6 6 6 6
Initial wt., Ib 692 692 691 675 692
Final wt., Ib 839 931 914 875 923
Daily gain, Ib 1.05 1.71 1.59 1.43 1.65
Dressing per cent 54.94 57.82 56.25 56.45 55.84
Cooler shrink, % 1.20 0.76 0.79 0.71 0.58
Supp./cwt gain, Ib 0 351 377 420 364
1Average of three trials, 119 to 127 days in length.
SSteers fed 140 days
3 Mixed feed contained 40.0% ground snapped corn, 38.3% dried citrus pulp,
20.0% cottonseed meal, and 1.7% complete mineral mixture.
Table 8.-Average performance of steers fed different levels of pelleted and non-pelleted citrus pulp (5).1
Per cent citrus pulp in concentrate mixture2
Non-pelleted pulp Pelleted pulp
0 22 44 66 0 22 44 66
Initial weight, Ib 732 738 728 735 742 728 733 732
Final weight, Ib 974 1035 1014 986 1046 1022 1055 1024
Total gain, Ib 242 297 286 251 304 294 272 292
Daily gain, Ib 2.52' 3.09 2.98 2.61 3.17 3.06 2.83 3.04
Daily consumption, lb
Concentrate 22.41 24.50 23.47 22.13 23.70 24.12 23.25 22.80
Bermudagrass hay' 3.34 3.47 3.37 3.41 3.50 3.52 3.45 3.36
Total 25.75 27.97 26.84 25.54 27.30 27.64 26.60 26.16
Feed/cwt. gain, Ib 1022 964 901 979 858 903 943 861
1 On feed 96 days.
2 Dried citrus pulp either regular or pelleted (s% inch pellets), was substituted for a corn-cob and shuck mixture (80% cornmeal-20%
ground cobs and shucks) in the amounts indicated.
3 Final weight was determined by shrinking the full weight 3%.
4This lot contained a nervous steer which gained only 1.60 pounds per day and which may have influenced performance of all steers
in the lot.
6 After 21 days, 2 pounds of hay feed per steer daily.
Good quality dried citrus pulp is an excellent, high-energy,
feed that can be used in rations for finishing cattle in drylot, or
on pasture. Concentrate mixtures can contain 40 % dried citrus
pulp with excellent results. Higher levels can be used by ex-
perienced feeders. If more than 60% of the concentrate is
citrus pulp, rumen parakeratosis may occur in cattle being full-
fed in drylot. However, straight citrus pulp can be limited fed
on pasture with excellent results and will produce no harmful
It is important to properly evaluate dried citrus pulp. Dark
pulps may have been overheated and charred during the de-
hydrating process and will have less digestible energy and
protein than good-quality pulp. When citrus pulp is used in
concentrate feeds, special attention should be taken to be sure
the rest of the diet includes adequate protein, fiber, and phos-
Pelleted citrus pulp can be used in finishing rations. How-
ever, more information is needed concerning the level that is
best to use in beef cattle ration formulation.
DRIED CITRUS MEAL
Dried citrus meal consists of small particles of peel, pulp,
and seed that pass through sieves during the processing of citrus
waste into dried citrus pulp. The average annual production of
dried citrus meal in Florida during 1964 to 1969 was 12,800
The average nutrient composition of dried citrus meal is
shown in Table 9. The appearance and composition of com-
mercial sources of dried citrus meal may vary widely, depending
upon the kind of drying equipment and sieves used to process
the citrus residue and the kind of fruit being processed. Steam
drying methods can produce a better quality citrus meal than
direct fire driers, as there is less charring of the citrus residue.
The color of dried citrus meal may vary from golden yellow
to black depending on the degree of charring during drying.
Charred, black citrus meals and citrus mill dust have a lower
nutritional value for livestock. Every effort should be made to
eliminate charring. The seed particles in dried citrus meal im-
part some of its golden color and much of its protein and fat
Table 9.-Average composition of dried citrus meal (%).1,2
Ether extract 2.62
Crude protein 7.16
Crude fiber 14.32
Nitrogen-free extract 63.18
1 Feed ingredient analyses for Official Samples from 1962-69. Feed Laboratory,
Division of Chemistry, Florida Department of Agriculture, Tallahassee.
2 Each figure an average of 25 samples.
Feeding Value of Dried Citrus Meal
Research (27) has shown that high quality citrus meal may
contain as much as 6.46% crude protein and 70% to 72% TDN,
about equal to dried citrus pulp. The digestibility of nutrients
in dried citrus meal and dried citrus pulp by cattle has been
reported to be similar (25, 31, 33, 34). In a feeding trial (12)
yearling steers ate high quality citrus meal more readily than
citrus pulp and gained slightly more weight. It was concluded
that either citrus meal or pulp was a satisfactory substitute
for one-third of the ground snapped corn in a ration containing
up to 40% citrus molasses.
Other research (23) showed that corn meal could be re-
placed in pelleted, high concentrate rations by high quality
steam-dried citrus meal plus sources of phosphorus and protein.
Five lots of yearling steers were self-fed diets which contained
0, 15.8%, 31.6%, 47.4%, or 63.2% of steam-dried citrus meal.
Weight gains among lots at the end of the 142-day trial were
similar, except the lot which received the ration containing
63.2% dried citrus meal had more variability in gains. Steers
fed rations containing 0, 15.8%, and 31.6% dried citrus meal
had almost equal feed efficiency, but feed efficiency was reduced
when rations contained 47.4%, and 63.2% of dried citrus meal.
Decreased efficiency of feed conversion was correlated with an
increased acetic acid and decreased propionic acid level in rumen
The two higher levels produced an apparently harmful alter-
ation of the rumen mucosa: papillae were darker, smaller, and
more irregular in shape; papillae were partially coated or en-
crusted and showed a high incidence of regression. As the per
cent of dried citrus meal in the diet increased, the dressing
percentage, carcass grade, marbling score, and back-fat thick-
ness decreased, but the carcass yield grade and estimated yield
of rib, loin, round, and rump increased. All rations produced
steaks of excellent and equal tenderness and juiciness. The per-
centage saturated fatty acid composition of backfat was in-
creased by the addition of steam dried citrus meal to the ration.
The appearance, composition, and feed value may be dif-
ferent for dried citrus meals obtained from different processors;
therefore, the meals should be inspected and valued accordingly.
Dried citrus meal which is bright and golden in color should be
used in preference to one that is charred or dark in color. It
should be bulky and preferably not be of a fine sand-like con-
sistency. The same precautions should be taken as with citrus
pulp, to see that protein, fiber, and phosphorus levels are prop-
erly balanced. High quality steam-dried citrus meal, properly
supplemented, can replace up to about 60% of corn meal and
comprise up to about 40% of formulas for finishing yearling
cattle. A decrease in feed conversion efficiency may be experi-
enced with each increase in dried citrus meal above 40%.
Rations to be creep-fed to suckling calves should be formulated
to contain no more than 40% of the highest quality citrus meal.
Dried citrus meal can be fed free choice in conjunction with
CITRUS SEED MEAL
The availability of citrus seed meal depends on whether
citrus seeds can be separated profitably from citrus pulp. Cur-
rent annual production is about 3,000 tons and may increase
in the future. Dried citrus pulp has been reported to contain
from 1.83% to 8.27% seeds with an average seed content of
4.75% (2). There has been some interest expressed in separat-
ing the seeds providing a suitable and profitable market for
citrus seed oil develops. If this occurs, the remaining citrus
seed meal would be available for animal feeding.
Citrus seed meal is left after the oil has been extracted from
the citrus seed. It varies in protein content, but its average
value is 23.2%. If the hulls are removed from the seeds, the
protein level is increased from 14.6% to 17.6%, if the fat is
not extracted. If the fat is first extracted, the protein level will
vary from 26.5% to 43.0% depending on whether a complete
ether extraction occurs.
Feeding Value of Citrus Seed Meal
A trial in 1950 (20) showed that citrus seed meal, contain-
ing 35% protein, was equal in value to cottonseed meal as the
sole source of supplemental protein for finishing steers. No
significant differences were found between the steers fed citrus
seed meal or cottonseed meal with regard to weight gain, feed
efficiency shrinkage in transit to market, carcass, yield and
grade, or in general appearance. During the same study citrus
seed meal was fed to two steers for a year to determine if the
material was toxic to cattle. No evidence of toxicity occurred
in the performance of the animals, and none was observed in a
gross pathology examination at slaughter.
A digestion trial with lambs (6) showed that the protein in
citrus seed meal, when supplied at a level of 88% of the total
protein in the ration, was equal in digestibility and biological
value to the protein from two samples of soybean meal. The
average digestibility of the protein in the citrus seed meal and
soybean meal rations was 64% and 61%, respectively.
Citrus seed meal can be used in beef cattle rations as a sub-
stitute for protein supplements such as cottonseed meal and
soybean meal. Limited research data indicate citrus seed meal
can be substituted entirely for other protein supplements; how-
ever, it is recommended that citrus seed meal not replace more
than one half cottonseed meal or soybean meal in beef cattle
rations, especially with young calves.
Citrus molasses is manufactured from the bound juice re-
leased from limed, cured, and pressed orange and grapefruit
peel residues. For example, after the juice is extracted from
1,000 boxes (85,000 pounds) of fresh grapefruit, approximately
3,215 pounds of citrus molasses may be produced from press
liquor obtained from the cured peel and pulp residue (22).
Commercial production of citrus molasses was begun during
the 1941-42 season with an output of 2,500 tons. Annual pro-
duction rose rapidly to 58,000 tons in 1946-47, with little in-
crease thereafter (21,37). Although production of dried citrus
pulp continued to increase after 1946-47, the practice of blend-
ing the molasses with citrus pulp limited the output of citrus
molasses until the early 1960's. As mentioned earlier, some
producers of citrus feeds have recently installed equipment
which will dry citrus peel residue including liquids, thereby
eliminating the separate production of citrus molasses. This
development will undoubtedly reduce production of citrus mo-
lasses somewhat. However, information from citrus processors
indicates that a considerable tonnage of molasses will continue
to be available in the future.4'5
Citrus molasses in Florida is required to have 45% total
sugar, have a Brix of 71, and weigh approximately 11.3 pounds
per gallon. It resembles blackstrap molasses but has less dry
matter (Table 10) to insure proper viscosity that is sometimes
a problem due to insoluble suspended material (21). Typical
analyses of Florida citrus molasses are presented below (22,
Total sugars, % 45
Crude protein, % 4.1 6.1
Dry matter, % 64 71
Crude fiber, % 0
Ash, % 4.3 4.7
Calcium, % 0.80
Phosphorus, % 0.06
nutrient, % 51.8 56.7
The total digestible nutrient content of citrus molasses has
been fairly uniform when considered on a dry matter basis
(16, 27). It is estimated to have 70% to 85% the value of No. 2
corn if fed at less than 35% of the concentrate, and 40% to
45% if fed at higher levels (32).
Comparative Composition of Citrus and Blackstrap Molasses
Considerable variation exists in molasses composition. Typ-
ical compositions for Florida-produced mill run blackstrap, cane,
' Coates, J. L. 1970. Personal communication.
SCummins, W. F. 1970. Personal communication.
Table 10.-Average composition of millrun blackstrap molasses, cane
molasses for feeding and citrus molasses (%).
blackstrap molasses for Citrus
molasses' feeding' molasses2
Dry matter 81 74 71
Crude protein 8-10 6-7 4
Total sugars 54 48 45
Phosphorus 0.10 0.08 0.06
Calcium 0.90 0.66 0.80
Total digestible nutrients 61 54 51
Digestible protein 4.7 4.3' 1.4
Level for fattening ration' 0-45 0-45 0-35
Relative value to #2 corn'
Limited fed 78-98 75-95 70-85
Overfed 45-55 40-50 40-45
1 Data obtained from U.S. Sugar Corporation for molasses produced on muck
2 Hendrickson and Kesterson (22)
3 Morrison (32)
and citrus molasses are presented in Table 10. Citrus molasses
is slightly lower than the other two molasses in dry matter,
crude protein, and total sugars. When used as a supplement to
permanent pasture grasses, citrus molasses would have about
95% the feed value of cane molasses and 85% the value of mill-
run blackstrap molasses for beef cattle on a fresh wet basis.
Feeding Value in the Feedlot
In early studies, citrus molasses was tried in relatively high
roughage (40%) finishing rations, without stilbestrol, with a
resultant 7.5% increase in feed intake, 25% increase in rate of
gain, and 12.8 % improvement in feed efficiency. In these studies
citrus molasses replaced half of the ground snapped corn in a
high roughage ration that produced a low level of performance
and feed conversion with feedlot steers (11). Citrus molasses
was superior to blackstrap at this high level of molasses intake
(13). Other feedlot trials indicated that citrus and blackstrap
molasses had a similar feeding value. (29).
In later studies with lower roughage rations, and added stil-
bestrol, cattle performance was better and the degree of re-
sponse to citrus molasses was not as great as with the earlier
less efficient rations (11). However, as shown in Table 11, add-
ing citrus molasses to either a ground snapped corn or ground
shelled corn ration improved feed efficiency. Similarly, as shown
in Table 12, adding citrus molasses has improved gain and feed
efficiency with high moisture corn as well as with dry corn.
Table 11.-Average gain and feed efficiency of steers fed citrus molasses
Ground snapped corn Ground shelled corn
No Citrus No Citrus
molasses molasses molasses molasses
Total gain, Ib 249 291 266 274
Daily gain, Ib 2.28 2.67 2.44 2.51
Daily feed intake, Ib:
Citrus molasses 3.61 3.61
Remainder of ration 22.55 22.32 23.73 20.47
Feed/100 Ibs gain, Ib 1007 965 991 949
SAverage of three trials.
Table 12.-Average gain and feed efficiency of steers receiving citrus
molasses with dry and high moisture corn.1
Dry corn High moisture corn
No Citrus No Citrus
molasses molasses molasses molasses
Total gain, Ib 246 284 289 328
Daily gain, Ib 2.30 2.65 2.70 3.09
Daily feed intake, Ib:
Citrus molasses 3.64 3.64
Remainder of ration 25.74 23.34 25.80 24.90
Feed/100 Ibs gain, Ib 1125 998 958 904
1 Average of two trials.
Feeding Recommendations for Feedlot Cattle
Citrus molasses can be included in beef cattle finishing ra-
tions up to a level of 10 % to 20 % of the concentrate. It can be
substituted for corn or other cereal grains. Larger quantities
of citrus molasses may be used if grain is high priced and
molasses is relatively cheap. Do not feed enough molasses to
restrict total feed intake. There is much variation in the com-
position of citrus molasses, and there appears to be some differ-
ence in the amount of molasses that different groups of cattle
will readily consume. If a high level of citrus pulp is fed, the
amount of citrus molasses should be limited. A maximum of
40% of the combined citrus molasses and pulp will probably
give best results. Citrus molasses may be fed satisfactorily to
finishing cattle by mixing with the feed, by pumping in the
trough between layers of dry feed, or by pouring it on top of
the dry feed in the trough without mixing, or by self-feeding.
Feeding Value on Pasture
In a series of trials at the Agricultural Research and Educa-
tion Center, Belle Glade, corn, citrus pulp, cane molasses, and
citrus molasses were compared as supplements to pasture for
finishing steers (19). As shown in Table 7, weight gains were
similar with the various supplements, but feed conversion was
less efficient than with the other supplements.
Feeding Recommendations for Pasture Cattle
1. Citrus molasses can be used very satisfactorily as a supple-
ment to permanent pasture. It is a high energy feed, rela-
tively low in crude protein and phosphorus. If it is used as
the principal supplemental feed, extra, protein and phos-
phorus should be provided for cattle, unless the forage con-
tains enough of these nutrients.
2. Use the kind of molasses that is the most economical in cost,
based on its relative feeding value.
3. Voluntary intake of citrus molasses will be more than that
of blackstrap molasses. The maximum recommended amount
is usually 6 pounds per animal daily. If the intake is to be
kept at 6 pounds, it may be necessary to limit the amount
WET CITRUS PULP
Wet citrus pulp is the residue from fresh fruit after the juice
or pulp are removed. As with dried citrus pulp, its composition
will vary considerably (22) depending upon the variety of
citrus pulp involved, percentage of seed, and manufacturing
processes used. Typically it will contain approximately 18% to
25% dry matter, 1.2% to 2.2% crude protein, 2.2% to 4.6%
crude fiber, 12% to 18% nitrogen free extract, 1.2% to 2.7%
ether extract, and 0.7% to 1.5% ash.
Utilization of citrus residue has been of concern to the Flor-
ida citrus industry since 1911 (38). For the first few decades
the fresh residue was dumped on the ground and cattle were
allowed to help themselves. This practice has not been widely
followed during the past 25 years, except when residue produc-
tion exceeded the drying capacity of a citrus processing plant
or when an occasional load of cull fruit was dumped on a
Early studies indicated that the fresh citrus residue was an
acceptable livestock feed but that better utilization could be
made of the feed when it was dried. However, there may still
be instances when the fresh citrus residue can be used econom-
ically in feeding programs.
Fresh Wet Citrus Pulp
Work in California in the 1920's (36) indicated that fresh
orange pulp could be used successfully in dairy rations if mixed
with other ingredients to make it more palatable. Fresh grape-
fruit was fed routinely by Florida dairymen before dried citrus
pulp became widely accepted (10), and fresh pulp was also used
as a supplement to native range pasture forage for beef cattle
(26). A later report (14) indicated that fresh citrus pulp could
be used as a winter supplement to pasture if transportation
costs were not excessive and substantiated that fresh grapefruit
was more palatable than fresh orange pulp. The value of various
citrus by-products for beef cattle has been reviewed earlier
(27), and feeding recommendations have been made for feeding
cull grapefruit and oranges, dried citrus pulp, citrus meal, and
citrus molasses to beef cattle.
Feeding studies with beef cattle (28) indicate that rate of
weight gain will be directly related to the level of TDN intake.
Fresh grapefruit was again shown to be more palatable than
fresh orange pulp. The palatability of orange pulp was im-
proved by removing essential oils from the skin of the fruit, but
this operation was not considered to be economically feasible.
These studies revealed that fresh citrus pulp was a good feed
for cattle if intake could be increased and the moisture content
8" 0 --,-- -- -- -- -- -- -
"7 60 -- __ ____-
30 -- -- --- -- -- ---- --
20 ----- -- -- -- --^- --
90 80 70 60 50 40 30 20 10 0
DRY MATTER %
Figure 2.-Nutritional or economic value of citrus pulp in relation to its
dry matter content. Regular pulp is assumed to contain 90% dry matter.
reduced. As shown in Figure 2, the greater the water content
of the fresh fruit the lower the nutritional value of fresh pulp.
Wet Citrus Pulp Silage
The fresh residue is relatively high in moisture, and if
ensiled there will be considerable loss of moisture and water
soluble nutrients. Several feeding studies with citrus pulp silage
were conducted during the early 1940's (17). Citrus pulp lost
21% in weight when ensiled in a trench silo, with most of the
losses being soluble carbohydrates. The inclusion of hay or
sugarcane improved the silage quality and increased efficiency
of preservation. Plain citrus pulp silage was less palatable than
citrus silage made in combination with hay or sugarcane, but it
was readily eaten after beef cattle became accustomed to it.
Recent investigations6 have been conducted in which fresh
citrus pulp was ensiled in combination with whole corn and soy-
bean meal. After being ensiled for 3 weeks, the mixture was
palatable and was readily eaten by steers. However, the fresh
citrus pulp mixed with whole corn and soybean meal produced
a plastic-like mixture that could not be handled easily. More
study is needed regarding the type of equipment that will be
needed to handle this type of mixture. When stored in a sealed
container, there was no spoilage after three weeks. The mixture
that was stored in the open with no cover developed a hard, foul
smelling crust on top. When this crust was removed, the silage
mixture underneath was readily consumed.
The inclusion of other feeds with fresh citrus pulp will re-
duce the water content of fresh pulp and increase total diges-
tible nutrients and crude protein content. The resulting mixture
can be ensiled or fed fresh. Cattle may have to be taught to eat
the mixture, but after they are accustomed to it they will con-
sume it readily.
The extent to which fresh or ensiled wet citrus pulp is fed
will depend on the relative cost of nutrients in the pulp as com-
pared to nutrients in other available feed ingredients and upon
localized conditions where cull citrus fruit is available or where
fresh pulp production exceeds the drying capacity of a fruit
processing plant. When this occurs, the wet pulp may be fed to
cattle, thus helping defray disposal costs by converting a poten-
tial waste product to a useful product.
Wet citrus pulp is a carbohydrate feed low in both crude
protein and crude fiber and relatively high in moisture. If fed
in drylot, it should be fed in combination with a protein supple-
ment, a dry carbohydrate material, a source of roughage, vita-
min A, and a well balanced mineral supplement if the diet is to
be nutritionally well balanced. When fed as a supplement to
pasture, it should be fed in combination with protein and
6 Chapman, H. L. 1970. Unpublished data.
SUMMARY AND DISCUSSION
The results of research to determine the feeding value of
dried citrus pulp, citrus meal, citrus seed meal, citrus molasses,
and wet citrus pulp have been presented. These are excellent
beef cattle feeds if used properly. The nutrient composition of
the various feeds will vary considerably and should be properly
evaluated before using them in beef cattle diets. They are all
excellent sources of digestible energy. Dried citrus pulp is high
in calcium and digestible energy, but low in digestible protein
and phosphorus. If properly supplemented with protein and
phosphorus, it can be used to furnish 40% of feedlot rations,
with excellent results. Pelleted citrus pulp is well utilized in
the feedlot, but it loses some of its "roughage property," and
this should be considered when using the pelleted material.
Citrus meal should be used with care, as it varies greatly in
chemical and physical properties. Good quality dried citrus
meal, if properly supplemented, can replace up to 60% of corn
meal and be used to a maximum of 40% of the total ration. It
is also high in calcium and digestible energy and low in protein
and phosphorus and should be properly supplemented with
Citrus seed meal contains variable protein level, but will
average around 23%. It is low in fiber, and variable in fat con-
tent, crude fiber and nitrogen-free extract. It can be used as a
substitute for other plant protein supplements in beef cattle
Citrus molasses has been successfully used both on pasture
and in the feedlot. It can be fed at the 10% to 20% level in
feedlot rations quite successfully, and at higher levels if the
price of other feedstuffs warrant. It has been used successfully
as the total supplement for cattle on pasture and its use for this
program should be based on cost relative to other feedstuffs. A
maximum of 6 pounds per animal daily on pasture is usually
Wet citrus pulp is not widely used because of the economics
of transporting and handling a material containing 75% to 85 %
moisture. However, it is a carbohydrate feed, low in crude fiber,
and crude protein and can be used in a cattle feeding program
if economics or other conditions warrant. It should be fed in
combination with a protein supplement, a dry carbohydrate
material, roughage, vitamin A, and a well-balanced mineral
Much research has been conducted during the past 60 years
by the Florida Agricultural Experiment Stations. However,
newer technology has created a need for additional research
that will provide beef cattlemen with further information that
will allow them to better use citrus feeds. For example, citrus
feeds need to be standardized so that they will produce a uni-
form effect when fed to cattle. Processors are encouraged to
describe their products so that buyers will know exactly what
they are purchasing. More information is needed on what levels
of the citrus feeds can best be used as supplements for cows, for
developing calves, and for finishing cattle. More citrus pulp is
being pelleted each year, and more information is needed on
how pelleted citrus pulp can be used in the above programs.
Information is needed on how much molasses can be added back
to citrus pulp and the effect it has on the feeding value of pulp.
More data is needed on the effect of other production variables
such as temperature on the feeding value of pulp. If fresh citrus
pulp is to be used, more information is needed on the equipment
needed to handle the wet product and also on how it can best be
incorporated into beef cattle feeding programs.
However, despite the need for additional research data, much
information is already available which proves conclusively, that
if used properly, citrus feeds can be profitably fed in beef cat-
1. Ammerman, C. B., and L. R. Arrington. 1961. Re-evaluation of citrus
pulp as a feed. Proc. Florida Nutrition Conference. p. 20.
2. Ammerman, C. B., J. F. Easley, L. R. Arrington, and F. G. Martin.
1966. Factors affecting the physical and nutrient composition of dried
citrus pulp. Proc. Fla. State Hort. Soc. 79:223.
3. Ammerman, C. B., R. Hendrickson, G. M. Hall, J. F. Easley, and P. E.
Loggins. 1965. The nutritive value of various fractions of citrus pulp
and the effect of drying temperature on the nutritive value of citrus
pulp. Proc. Fla. State Hort. Soc. 78:307.
4. Ammerman, C. B., F. G. Martin, and L. R. Arrington. 1968. Nutrient
and mineral composition of citrus pulp as related to production source.
Proc. Fla. State Hort. Soc. 81:301.
5. Ammerman, C. B., F. C. Neal, A. Z. Palmer, J. E. Moore, and L. R.
Arrington. 1967. Comparative nutritional value of pelleted and reg-
ular dried citrus pulp when fed at different levels to finishing steers.
Animal Sci. Mimeo Rpt. AN67-7. Fla. Agr. Exp. Sta., Gainesville.
6. Ammerman, C. B., P. A. vanWalleghem, J. F. Easley, L. R. Arrington,
and R. L. Shirley. Nov. 4-7, 1963. Dried citrus seeds nutrient com-
position and nutritive value of protein. Proc. Fla. Hort. Soc. 76:245.
7. Ammerman, C. B., P. A. vanWalleghem, A. Z. Palmer, J. W. Car-
penter, J. F. Hentges, and L. R. Arrington. 1963. Comparative feed-
ing value of dried citrus pulp and ground corn and cob meal for
fattening steers. Animal Sci. Mimeo Rpt. AN64-8, Fla. Agr. Exp.
8. Ammerman, C. B., P. W. Waldroup, L. R. Arrington, R. L. Shirley,
and R. H. Harms. 1966. Nutrient digestibility by ruminants of poultry
litter containing dried citrus pulp. Agr. and Food Chem., 14:279.
9. Ammerman, C. B., and J. M. Wing. 1963. Physical breakdown of
whole citrus seeds and digestibility of rations high in citrus seeds by
ruminants. Animal Sci. Mimeo Rpt. AN63-12 and Dairy Sci. Mimeo
Rpt. 63-5, Fla. Agr. Exp. Sta., Gainesville.
10. Arnold, P. T. Dix, R. B. Becker, and W. M. Neal. 1941. The feeding
value and nutritive properties of citrus by-products II. Dried grape-
fruit pulp for milk production. Fla. Agr. Exp. Sta. Bul. 354.
11. Baker, F. S., Jr. 1955. Steer fattening trials in North Florida. Fla.
Agr. Exp. Cir. S-89.
12. Baker, F. S., Jr. 1955. Citrus molasses, dried citrus pulp, citrus meal
and blackstrap molasses in steer fattening rations. North Fla. Exp.
Sta. Mimeo Rpt. 55-3.
13. Baker, F. S., Jr. 1956. Steer fattening program for North Florida.
North Fla. Exp. Sta. Mimeo Rpt. 56-6.
14. Becker, R. B., and P. T. Dix Arnold. 1951. Citrus pulp in dairy
rations. Fla. Agr. Exp. Sta. Cir. S-40.
15. Becker, R. B., P. T. Dix Arnold, and George K. Davis. 1948. Citrus
by-products as feeds for cattle. Fla. Agr. Exp. Sta. Bul. 644.
16. Becker, R. B., P. T. Dix Arnold, G. K. Davis, and E. L. Fouts. 1946.
Citrus molasses. Fla. Agr. Exp. Sta. Bul. 623.
17. Becker, R. B., G. K. Davis, W. G. Kirk, P. T. Dix Arnold, and W. P.
Hayman. 1954. Citrus pulp silage. Fla. Agr. Exp. Sta. Bul. 423.
18. Chapman, H. L., Jr., C. E. Haines, and R. W. Kidder. 1961. Feeding
value of limited fed mixed feed, citrus pulp, ground snapped corn
and blackstrap molasses for fattening steers on pasture. Everglades
Sta. Mimeo Rpt. 61-19. Everglades Exp. Sta., Belle Glade, Fla.
19. Chapman, H. L., Jr., R. W. Kidder, and S. W. Plank. 1953. Compar-
ative feeding value of citrus molasses, cane molasses, ground snapped
corn and dried citrus pulp for fattening steers on pasture. Fla. Agr.
Exp. Sta. Bul. 531.
20. Glasscock, R. S., T. J. Cunha, A. M. Pearson, J. E. Pace, and D. M.
Buschman. 1950. Preliminary observations on citrus seed meal as a
protein supplement for fattening steers and swine. Fla. Agr. Exp.
Sta. Cir. S-12.
21. Hendrickson, R., and J. W. Kesterson. 1964. Citrus molasses. Fla.
Agr. Exp. Sta. Tech. Bul. 677.
22. Hendrickson, R., and J. W. Kesterson. 1965. By-products of Florida
citrus. Fla. Agr. Exp. Sta. Bul. 698.
23. Hentges, J. F., Jr., J. E. Moore, A. Z. Palmer, and J. W. Carpenter.
1966. Replacement value of dried citrus meal for corn meal in beef
cattle diets. Fla. Agr. Exp. Sta. Tech. Bul. 708.
24. Hillis, W. G., C. B. Ammerman, A. Z. Palmer, and L. R. Arrington.
1969. Fossil shell flour (Diatomaceous Earth) in combination with
urea or soybean meal for finishing steers. Animal Sci. Mimeo Rpt.
AN69-12, Fla. Agr. Exp. Sta., Gainesville.
25. Keener, H. A., N. F. Colovos, and R. B. Eckberg. 1957. The nutritive
value of dried citrus pulp for dairy cattle. New Hampshire Agr. Exp.
Sta. Bul. 438.
26. Kirk, W. G., 1947 and 1948. Utilization of citrus products for fatten-
ing cattle. Fla. Agr. Exp. Sta. Annual Rpt. Pages 235 (1947) and
27. Kirk, W. G., and G. K. Davis. 1954. Citrus products for beef cattle.
Fla. Agr. Exp. Sta. Bul. 538.
28. Kirk, W. G., E. R. Felton, H. G. Fulford, and E. M. Hodges. 1949.
Citrus products for fattening cattle. Fla. Agr. Exp. Sta. Bul. 454.
29. Kirk, W. G., E. M. Kelly, H. G. Fulford, and H. E. Henderson. 1956.
Feeding value of citrus and blackstrap molasses for fattening cattle.
Fla. Agr. Exp. Sta. Bul. 575.
30. Kirk, W. G., and M. Koger. 1970. Citrus products in cattle finishing
rations. A review of research at Range Cattle Experiment Station.
Fla. Agr. Exp. Sta. Tech. Bul. 739.
31. Mead, S. W., and H. R. Guilbert. 1926. The digestibility of certain
fruit by-products as determined by ruminants. 1. Dried orange pulp
and raisin pulp. Calif. Agr. Exp. Sta. Bul. 409.
32. Morrison, S. H. 1969. Ingredient analysis and estimated feed value
tables for beef and sheep rations, 1969-70. Feedstuffs 41:49.
33. Neal, W. M., R. B. Becker, and P. T. D. Arnold. 1934. Dried grape-
fruit refuse a valuable feed. Fla. Agr. Exp. Sta. Press Bul. 466.
34. Neal, W. M., R. B. Becker, and P. T. D. Arnold. 1935. The feeding
value and nutritive properties of citrus by-products. 1. The digesti-
ble nutrients of dried grapefruit and orange cannery refuses and the
feeding value of grapefruit refuse for growing heifers. Fla. Agr. Exp.
Sta. Bul. 275.
35. Peacock, Fentress M., and W. G. Kirk. 1959. Comparative feeding
value of dried citrus pulp, corn seed meal and ground snapped corn
for fattening steers in drylot. Fla. Agr. Exp. Sta. Bul. 616.
36. Regan, W. M., and S. W. Mead. 1927. The value of orange pulp for
milk production. Calif. Agr. Exp. Sta. Bul. 427.
37. Statistical summary for 1970. Florida Canners Association, Winter
38. Walker, S. S., and F. A. McDermott. 1917. The utilization of cull
citrus fruits in Florida. Fla. Agr. Exp. Sta. Bul. 135.
Proposed Descriptive Nomenclature for Citrus By-Product Feedstuffs
A nomenclature system1 for feedstuffs has been proposed
which defines more specifically the feed with regard to its origin,
part of plant represented, type of processing, and certain other
factors. In applying this system to citrus feeds, the following
terms are used to describe the feed more accurately. According
to this system, citrus meal is referred to as citrus fines and citrus
molasses as citrus syrup. The term meal has been reserved for
ground ingredients such as soybean meal, and "fines" represent
materials resulting from a screening process such as occurs with
citrus pulp. Molasses indicates a by-product from refined sugar
production, and syrup denotes a secondary product produced
during the process of extracting and concentrating the juice of
a fruit. The use of this type of system would be of value in es-
tablishing more uniform citrus feeds, would assist in marketing,
and would aid in the efficient utilization of the materials from
a nutritional standpoint. A partial listing of terminology is
Citrus, pulp, dehydrated
Citrus, pulp, fines, dehydrated
Citrus, pulp, pressed, dehydrated
Citrus, fines, dehydrated
Citrus, fines, pressed, dehydrated
Citrus, syrup, 45% invert sugar, 71 degrees brix
Citrus, seed, mech-extd ground
The above terms can be used, particularly with regard to
citrus pulp and citrus fines, to describe more accurately the type
of processing which they have undergone. For example, if the
fines have been removed, this is indicated for the remaining
pulp. The term "pressed" indicates whether this procedure has
been used as an aid in dehydration.
SUnpublished data obtained from L. E. Harris.
Glossary of Feed Terms1
The following is a list of terms which are used in the Inter-
national Feed Names. They describe: (1) the part of the parent
material eaten, (2) the process (es) used in its preparation,
(3) the physical form of the part as a single ingredient or the
form of a mixture of parts prepared for feeding, and (4) other
relevant miscellaneous terms.
APPARENT DIGESTIBLE ENERGY (DE). (term) Food-intake gross
energy minus fecal energy. Similar terms: Apparent ab-
sorbed energy; energy of apparently digested food.
DE = (GE of food per unit dry wt x dry wt of food) (GE
of feces per unit dry wt x dry wt of feces)
GE (GE of food per unit dry (GE of feces per unit dry
digestion = wt x dry wt of food) wt x dry wt of feces)
coefficient GE of food per unit dry wt x dry wt of food x 100
ASH. (part) Mineral residue remaining after the burning of
BLOWINGS. (part) See Mill dust.
BRIX DEGREE. A measure of the density of concentration of sugar
solutions. When applied to molasses or syrup, it is a measure
of soluble solids.
BY-PRODUCT. (part) Another products) produced by a process
incidental to its primary purpose.
CALORIE. (cal) is the amount of heat required to raise the tem-
perature of 1 g water to 15.5 degrees centigrade from 14.5
CANNERY RESIDUE. (part) Edible residue obtained from the prep-
aration of a product for canning.
'The terms and definitions in this glossary are taken from Bulletin 479
of the Utah Agricultural Experiment Station, An International Feed
Nomenclature and Methods for Summarizing and Using Feed Data To
Calculate Diets, by Lorin E. Harris, J. Malcolm Asplund, and Earle W.
Crampton (Logan, Utah: 1968).
CITRUS MILL DUST. See mill dust.
DRIED. (process) Water or other liquid removed. (International
DUST. (part) Fine, dry particles of matter usually resulting
from the cleaning or grinding of grains or other feedstuffs.
FAT. (part) A substance, solid or plastic at room temperature,
composed chiefly of triglycerides of fatty acids.
FEED(S). (term) Edible materials) which are consumed by
animals to contribute energy and/or nutrients to the animal's
diet. (Usually refers to animals rather than man.)
FIBER. (part) An elongate tapering plant cell that has at ma-
turity no protoplasm content. It is found in many plant
organs that are well developed in the zylem and phloem of
the vascular system. It imparts elasticity, flexibility, and
tensile strength to the plant.
FINES. (physical form) Any material which will pass through
a screen whose openings are immediately smaller than the
specified minimum crumble size or pellet diameter.
FRUIT. (part) The edible, more or less succulent, product of a
perennial or woody plant, consisting of the ripened seeds
and adjacent or surrounding tissues, or the latter alone.
GROSS ENERGY (GE) (term) The amount of heat, measured in
calories, that is released when a substance is completely
oxidized in a bomb calorimeter containing 25 to 30 atmos-
pheres of oxygen. Similar term: Heat of combustion.
GROUND. (process) Reduced in particle size by impact, shearing,
JOULE (J). (term) The International System of Weights and
Measures is referred to as the Mkgs system, derived from
the first three entries of the fundamental units the meter,
the kilogram and the second. Of particular interest to the
animal scientist is the derived unit for energy in terms of
heat, the joule(J). One calorie is equal to 4.184 joules. At
the present time, animal scientists are using the calorie as
the unit of measure for heat energy; however, sometime in
the future the joule may be used.
JUICE. (part) The aqueous substance obtainable from biological
tissue by pressing or filtering (with or without addition of
MEAL. (physical form) An ingredient which has been ground or
otherwise reduced in particle size.
MILL DUST. (part) Fine feed particles of undetermined origin
resulting from handling and processing feed and feed in-
METABOLIZABLE ENERGY. (ME) (term) is the food intake gross
energy minus fecal energy, minus energy in the gaseous
products of digestion, minus urinary energy.
MOLASSES. (part) The thick, viscous by-product resulting from
refined sugar production or the concentrated, partially de-
hydrated juices from fruits.
NET ENERGY (NE) (term) is the difference between metaboliz-
able energy and heat increment, and includes the amount of
energy used either for maintenance only or for maintenance
plus production. Net energy can also be expressed as the
gross energy of the gain in tissue or of the products synthe-
sized plus the energy requirement for maintenance. Below
the critical temperature the heat increment is also part of
When reporting net energy, it should be clearly stated which
functions are included. For example, there may be values
for net energy for maintenance plus production (NEm+,),
net energy for maintenance only (NEm), or net energy for
production only (NE,). The subscripts are suggested be-
cause there is often confusion in the literature concerning
which energy fractions are contained in net energy.
NET ENERGY FOR MAINTENANCE (NE m) (term) is the fraction
of net energy expended to keep the animal in energy equi-
librium. In this state, there is no net gain or loss of energy
in the body tissues. The net energy for maintenance for a
producing animal may be different than for a non-producing
animal of the same weight. This is due to changes in amounts
of hormones produced and to differences in voluntary ac-
tivity. This difference may be charged to maintenance, but
in practice it is usually charged to the production require-
NET ENERGY FOR PRODUCTION (NE,) (term) is the fraction of
net energy required in addition to that needed for body
maintenance that is used for work or for tissue gain (growth
and/or fat production), or for the growth of, for example,
a fetus, milk, eggs, or wool. It should always be clearly
stated which production fractions are included. For ex-
ample, there could be: NEegg; NEgain; NEmilk; NEreg;
NEwoo. ; NEwok.
PECTIN. (part) Any of the group of colorless amorphous methy-
lated pectic substances occurring in plant tissues or obtained
by restricted treatment of protopectin obtained from fruits
or succulent vegetables, that yield viscous solutions with
water, and which when combined with acid and sugar yield
PEEL. (part) Skin.
PELLETS. (physical form) Agglomerated feed formed by com-
pacting and forcing through die openings by a mechanical
process. Similar terms: Pelleted feed, hard pellet.
POMACE. (part) Pulp, seeds and stems from fruit. (International
PROTEIN. (part) Any of a large class of naturally-occurring
complex combinations of amino acids.
PULP. (part) The solid residue (including seeds and skins if
present) remaining after extraction of juices from fruits,
roots, or stems. Similar terms: Bagasse, pulp from sugar
cane; Pomace, pulp from fruits; Marc, pulp from grapes.
PULP. Plant material less juice.
PULP FINES. (part) Fine particles separated by screening from
pulp such as citrus pulp.
RESIDUE. (part) Part remaining after the removal of a portion
of its original constituents.
SEED. (part) The fertilized and ripened ovule of a plant.
SYRUP BY-PRODUCT. (part) Secondary product produced during
the process of extracting and concentrating the juice of a
fruit or plant.
Special recognition is given to a number of people whose
efforts have contributed significantly to the knowledge of using
citrus materials for livestock feeds. Many people in the Division
of Chemistry, Florida Department of Agriculture; many scien-
tists of the Florida Agricultural Experiment Station; citrus pro-
ducers and processors; feed manufacturers and many others
have contributed much to the knowledge of citrus feeds. In
addition, the Florida Citrus Processors Association in coopera-
tion with the Florida Citrus Commission has contributed funds
for research. Without the help of these and many others the
present knowledge of these feeds would not exist.