Texas Cooperative Extension
Prickly pear cactus has been utilized as a forage substitute for cattle and other grazing livestock in South Texas and Northern Mexico for over a century, as early as 1857 (Griffiths, 1905). A history of its use is well documented by others in the proceedings of a workshop held in 1989 (Hanselka and Paschal, 1989). The most common and widespread prickly pear species in Texas and Mexico are Englemann (Opuntia engelmanni), Nopal (O. Lindheimeri), and Plains (O. Polycantha) (Correa et al. 1987). Prickly pear is a mixed blessing on Texas rangelands with about as many ranches seeking to control it (16%) as utilize it for cattle feed (18%) (Hanselka et al., 1991). This paper will review some feeding trials and nutritional values of prickly pear as a livestock feed, primarily beef cattle, some potential feeding problems associated with prickly pear and indicate areas requiring further research and will comment on it’s current use as a cattle feed.
The use of prickly pear as an animal feed has been studied extensively by many researchers both in the U.S. and abroad. The nutrient content of prickly pear in varies according to various feeding forms, stages and ages of growth. In most reports, prickly pear fed “as is” is very high in moisture content (low in dry matter), energy, fiber and ash (mineral matter) but low in protein. This has been reported since the earliest published reports of its use.
One of the first documented reports of the use of prickly pear as livestock feed was published by Griffiths in 1905. He reviewed the use of prickly pear in dairy, beef cattle, swine, sheep and goat rations and found widespread use of per as a livestock feed in Texas at that time. He also reported that sometimes “pear balls” or balls of undigested fiber will develop as a result of feeding prickly pear alone and reported that feeding hay reduced the incidence of pear balls. The spines were also a problem as they needed to be singed off although cattle did apparently eat the green, unsinged pear readily. Most “pear cattle” he noted scoured heavily but not heavily enough to cause sickness and the scouring was reduced by adding sorghum hay to the diet (Griffiths, 1906). Griffiths (1905) was so impressed with the usefulness of prickly pear that he stated:
“The destruction of pear in southwestern Texas would be a severe calamity to the stock industry”.
In 1906, Griffiths published the results of two feeding trials in which dairy cows were fed prickly pear. In the first trial, the cows were fed from 60 to 149 pounds of chopped prickly pear plus 8 to 12 pounds of rice bran, 3 pounds of cottonseed meal and 8 to 15 pounds of sorghum hay daily. The cows fed only prickly pear ate between 99 and 174 (average 149) pounds daily compared to the 19 to 26 (average 23) pounds eaten by cows fed only sorghum hay. There was no apparent difference in either milk yield or butter fat percentage between the rations.
Griffiths (1906) stated that one man could feed 100 cows using only 10 gallons of gasoline (at 12 cents a gallon) to singe the pear. He concluded that “a full roughage ration of prickly pear with a constant grain ration appears to yield fully as good results as a full roughage ration of sorghum hay”. He also observed that frozen pear was eaten by cattle with “apparent relish” without any problems.
Griffiths (1906) second trial used 27 steers fed chopped, unsinged pear for 15 weeks as a fattening ration. The steers consumed an average of 96 pounds of pear and 4.3 pounds of cottonseed meal daily. The average daily gain of the steers during this period was 1.75 pounds. One pound of gain required either 55 pounds of pear or 2.5 pounds of cottonseed meal. The only drawback that Griffiths reported was the tremendous shrink that the cattle underwent when they were shipped to market.
The current thinking at the time was that the spines of the chopped pear were softened by the juices of the plant, a fact that Griffiths (1906) found was entirely erroneous. The chopping effect on the spines was one of abrasion, breaking and removal, rather than softening. Griffiths reported that cattle would eat pear as it stands in pastures in Texas, if the spines were more or less parallel to leaf compared to being at right angles.
One of the earliest nutrient analyses was reported in 1908 by Griffiths and Hare. They reported very low dry matter and crude protein content and high ash and fiber contents. The high ash content in prickly pear is due to the abundance of soluble salts in the arid and semi-arid soils of the southwest. The average ash content in the stem and fruit reported by Griffiths and Hare (1908) was 18.25%. The ash content would have been higher if not for the fruit which contains less ash than the stems. The average ash content of the fruit was 13.21%, and is found mostly in the seed. The mineral content of the ash is similar to that of other arid plants with the exception of potassium, manganese and calcium which are present in high amounts. It is the presence of these salts that probably cause cattle to scour.
The stems of the South Texas varieties are higher in fiber and lower in moisture and feed value than the upper leaves (Griffiths and Hare, 1908). Their analysis of the fruits of the cactus have shown them to contain more fat and protein than the stems, but the seeds actually contain most of the food material of the whole fruit.
Woodward et al (1915) reported two years of research on the use of prickly pear as a feed for dairy cows. The cows were fed equal parts of corn chop, wheat bran and cottonseed meal, sorghum hay (3.5 to 20 lbs) with and without medium (60 lbs) and heavy (100 to 150 lbs) levels of singed and chopped prickly pear. The cows were fed for two periods of 80 days each. These cows were compared to another group fed only cottonseed meal (4 lbs) and heavy prickly pear. The first year’s results indicated that prickly pear fed at a medium level gave the best results in milk yield and butter fat percent.
The second year, only a 75 pound level of prickly pear was fed and cottonseed hulls and sorghum silage were substituted for the cottonseed meal and sorghum hay. In addition, one group was fed only prickly pear. The results of this trial agreed wit the first in that moderate levels of prickly pear in the ration were better than heavy feedings. This was due to the lack of efficient digestion of the heavy ration. Woodward et al (1915) also found no effect of high levels of salt (6.5 oz/head/day) on reducing the laxative effect of prickly pear. Previously, it had been thought that adding salt to the prickly pear ration would reduce scours.
One interesting result in the fall trial by Woodward et al (1915) was that prickly pear feeding apparently reduced water consumption. Cows fed heavy levels of prickly pear in the fall drank only 5 pounds of water daily (8.3 lbs/gallon). Cows fed medium levels drank 30 pounds, while those fed only sorghum hay required 95 pounds. However, cows fed prickly pear alone did not drink any water. The same trial conducted in May and June indicated that the same four rations (heavy and medium levels of prickly pear, sorghum hay, and prickly pear alone) caused cows to drink 0, 44.3, 95 and 0 pounds of water. Normally a cow will drink 10 to 20 gallons (80 to 160 lbs) of water daily depending upon weight, temperature and physiological status. Many ranchers feel that cattle can easily survive on “pear water” if other sources of water are not available (Maltsberger, pers. com.).
The research also evaluated the effect of cold temperature on the “pear eaters” and found that milk production was reduced, probably due to the lack of energy in the diet from pear compared to that from the sorghum hay. Woodward et al (1915) concluded that cows can be maintained on pear if about 110 pounds are fed with two pounds of cottonseed meal. The pear level can be varied from 60 to 105 pounds if 3.5 to 6.0 pounds of sorghum hay is fed. Cows that consumed only prickly pear lost 30 pounds in 70 days indicating that protein and energy supplementation is required, especially for dairy cows.
In 1958, Belasco et al reported on a field test where prickly pear was sprayed with urea at the rate of 160 pounds/acre (72 lbs/N/acre) with 40 gallons of water containing a “spreader sticker”. The average level of nitrogen in the test increased from 1.44 to 1.73%. They also conducted a laboratory study using cactus pads dipped in a urea water solutions (50 or 200 lb/100 gallons). Those results showed that the nitrogen content increased to 1.8%, or 50% above the level of the untreated pads. The in vitro and in vivo digestibility of the cactus pads was increased by 12% in the laboratory trial and by 20% in the field trial. The digestible protein was increased from .27 to 4.14% in the dry cactus. These results indicated that prickly pear feeding may be combined with the use of non-protein nitrogen to improve crude protein percent in the diet and to improve the digestibility of the diet.
Plains prickly pear was evaluated as a cattle forage by Shoop et al (1976). Six pairs of heifers were fed for 84 days on a basal ration of hay pellets (11 lbs) and cottonseed meal (.7 lbs) at 2.3% of initial body weight. One heifer of each pair also ate singed prickly pear ad libitum (average 5.5 lbs/day). Prickly pear increased total dry matter consumption and weight gain 72% and average daily gain increased by .62 lb/head/day. The prickly pear contained about 40% more soluble carbohydrates than alfalfa hay but only 3.4% digestible protein. Although the level of pear in this trial was not nearly as high as in the previous trials, the use of small amounts of pear is apparently beneficial in reducing the levels of more expensive harvested hays and grains for energy sources.
Shoop et al (1976) reported that the only major factor that influenced the amount of prickly pear eaten by the heifer was the degree of burning of pads during singeing. Also, all heifers were reported to reject pear with spines remaining. However, the glochids (minute, hair-like spines), which frequently escaped burning, did not affect consumption. All heifers preferred just enough singeing to remove the large spines. A minor factor that did affect consumption was the accumulation of soot on the pads. The soot accumulated during the singeing when an excessive amount of grass and forbs was burned with the prickly pear. Feeding the prickly pear did not cause any feeding disturbances during the trial or for up to 60 days afterwards even though glochids appeared in the feces, apparently undigested. Another interesting result of this study was that at the conclusion of this trial, the heifers did not feed on prickly pear on the native range. This was in contrast to the work by Hoffman and Darrow (1955) who claimed that a major disadvantage of feeding prickly pear was that cattle would eat unsinged prickly pear as a result of discontinuing the feeding of singed prickly pear. Apparently cattle fed at least a balanced, maintenance ration will not eat unsinged prickly pear.
In a review of the nutritional aspects of several plants in South Texas, Holloway and Varner (1985) reported that prickly pear was sufficient in energy to meet the requirements of a dry, pregnant or lactating cow all year long, but was too low in crude protein content in the summer and winter to be used as the only feed source. They also reported that prickly pear met the phosphorus requirements of the dry and lactating cows only during the spring. This work supports previously cited work that protein supplementation is very necessary for cattle fed pear and that even though pear is high in most minerals, it is very low in phosphorus, a mineral critical for growth, reproduction and lactation. Both protein and phosphorus should be supplemented to “pear” cattle for best results. In fact, phosphorus should be supplied to cattle in South Texas all year long regardless of what they are fed.
In an economic analysis of pear feeding, prickly pear was reported by Correa et al (1987) to have 17.4% dry matter, 11% total digestible nutrients (TDN), 1.4% crude protein and .21 mcal/lb digestible energy (DE). When supplemented with 4.5 pounds of cottonseed meal, dry matter content, TDN, crude protein and DE increased to 21%, 13.9%, 2.92% and .25% mcal/lb, respectively. The cost of supplementing with prickly pear derived from a survey ranged from $.61-.64 per head per day in 1983 and from $.25-.63 in 1984 which compared very favorably to the cost of feeding hay ($1.58/head/day in 1983 and $1.84/head/day in 1984). A case study involving stocker steers in Webb County in 1993 reported that the cost of supplementing steers with prickly pear cost $.26 per head per day (Hanselka and Falconer, 1993) with an additional $.27 per head per day for supplemental feed costs (other than pear) to meet nutritional requirements. The grazing margin for these cattle was $33.62 per head, indicating that prickly pear with the proper supplement to balance the nutritional requirements, can be a profitable resource to graze stockers.
The Texas Agricultural Extension Service 1989 Comprehensive Ranch Management Survey of 37 counties lying south U.S. 90 (Hanselka et al , 1991) indicated that 18% (ranging from 7% in counties along the Gulf Coast to 40% in western counties bordering Mexico) of the ranchers in South Texas burn and feed prickly pear as a supplement for their cattle (over 60% in some southwestern counties) at an average cost of $ .39/head/day.
Proper Pear Burning and Nutritional Considerations
In proceedings from a conference held in 1989, ranchers discussed the use of prickly pear in emergency feed rations, supplements added to improve diet quality for higher production classes of animals, methods of burning, potential problems as a result of feeding prickly pear and methods to cultivate it on ranch lands (Hanselka and Paschal, 1993). Most pear is burned today with propane gas and is done so with hand held burners connected to five gallon propane tanks (although large ranches can and do use 100 – 250 gallon tanks on trailers or tractors with multiple hoses and two or more pear burners attached). A gallon of propane will burn enough pear to feed three to five cows, depending on the experience of the person burning. On a warm dry day an experienced person can burn enough pear to feed 200 cows.
To obtain most efficient burning, a pear “patch” should be selected that is at least 3 – 4 feet high rather burning smaller or individual plants. Ideally, plants that are at least 5 years of age are best to use. The burner should have the wind behind their back and the flame near the ground to ignite any dry grass or weeds in the pear stand and facilitate burning. This will also allow snakes and other small animals an opportunity to move away from the burner. Once the tender has burned and burned most of the spines from the pad, it is much easier to remove the remaining spines and conserve fuel. Care should be taken not to “over burn” the pads as may cause the cattle to scour more or possibly not eat them.
Cattle will eat a burned pear pad nearly to the ground and can consume about 10% of their body weight daily in pear, depending on the extent of use of pear in the ration. Care should be taken to keep cattle from eating the plant down to it’s base as it will increase the time for regrowth or even possibly kill the plant. Leave at least one joint above the base. It has been reported that cattle can consume 100 pounds of prickly pear in a day (Hanselka and Falconer, 1993). Enough pear can be burned for 2 – 3 days without refusal by cattle. Frozen pear is less palatable to cattle.
Cattle become accustomed to eating burned pear and will quickly travel to the sound of a pear burner. When burning is ceased for a long period of time, some cattle will continue to eat the green, unburned and fully spined pear, creating a condition called “pear mouth”. These cattle will have ulcerations of the tongue and depending the severity, may affect their ability to eat and have to be sold.
Long term feeding of prickly pear can cause the formations of “pear balls”, large ball-shaped fibrous masses that are formed in the rumen. These take up rumen area and can cause blockage and death. It has long been recommended that a high protein (or high nitrogen) source be fed as a supplement to pear cattle to aid in the reduction of pear balls (nitrogen aids in ruminant digestion of fiber in low quality diets). Most ranchers will feed cottonseed meal or cubes (1 – 2 lbs daily per head), a cottonseed meal and salt mix (2:1) , There is no cure for cattle that have pear balls.
Safety considerations for the burners need to be noted. Poisonous snakes live in and near the pear patches catching small animals that reside there, depending on the cactus spines to protect them form flying or larger land predators. These snakes are easily disturbed and with the noise of the pear burner are not often heard. Persons burning pear need to be aware of the possible presence of these snakes. Also, cattle actively eating pear while it is being burned can easily push one or another onto the person burning pear and injuring them or getting tangled in a propane hose. Burners need to keep hoses near them and cows away from them while they are burning.
Burning prickly pear is not recommended for horses.
The last 95 years of research still have not adequately defined the role of prickly pear in livestock diets. Griffiths’ 1905 review of management practices at the turn of the century is interesting but given today’s levels of production in beef feedlots and in dairy and swine production in the United States, it is doubtful that prickly pear has a significant place in modern feed rations. Prickly pear should not be fed to horses. However, there is still a need for nutritional and feeding specifications which would be very useful in other countries that may have lower levels of production due to climatic or nutrient constraints.
Prickly pear is still an important emergency feed resource for ranchers in South Texas for both beef cows and stockers. However, the nutrient content of prickly pear is often less than that required by any animal other than a dry, early bred, beef cow.
Prickly pear is very high in moisture content (consequently low in dry matter), as a result it often takes very large amounts of prickly pear (100 – 200 lbs) to satisfy minimal nutrient requirements. This level of water in the diet increases the rate of passage and leads to the scouring often seen in pear cattle. This increased rate of passage also reduces the absorption of nutrients contained in prickly pear. It is always advisable to feed some hay (depending upon cost and availability) or have a brush pasture that the cattle can utilize to increase their level of dry matter intake and reduce the rate of passage of the prickly pear. This will also reduce the incidence of pear or fiber balls in cattle caused by the high levels of crude fiber in prickly pear. Cattle have often been said to bloat (accumulate gasses in the rumen) on pear but more likely the distension on the left side of the rumen normally associated with bloat is caused by the large amounts of prickly pear fed to the cattle.
Crude protein and digestible protein levels are generally low in prickly pear especially when fed on the plant “as is” or after singeing (Griffiths and Hare, 1908, Fraps, 1932). Prickly pear is generally too low in crude protein to maintain a dry pregnant cow except in the early springs pads (Everitt and Gonzales, 1981 and Holloway and Varner, 1985), the fruit (Everitt and Gonzales, 1981) and the seed (Sawaya et al, 1983). As a result, it is always recommended that a good protein supplement be added to the diet of cattle fed prickly pear. At least one study (Belasco et al, 1958) indicated that a non-protein nitrogen source might be utilized in a prickly pear ration. Further studies are needed in this area as well especially in view of the fact that most spineless varieties are higher in crude protein content than spined varieties (Bath et al, 1980, Gregory, 1988).
Fortunately, prickly pear is moderately high in energy levels, either those expressed as TDN, DE or NE (Fraps, 1932, Shoop et al, 1976, Bath et al, 1980, Halloway and Varner, 1985). These energy levels vary, depending again on source of material. Since energy is often the first limiting nutrient on rangeland, is needed in the greatest amount and has a significant effect on reproduction, prickly pear should be considered as a “good feed”, albeit a slightly unbalanced one.
Prickly pear is generally very high in fiber (Griffiths and Hare, 1908, Hoffman and Darrow, 1954 and Bath et al, 1980) and ash (Griffiths and Hare, 1908 and Bath et al, 1980), both of which are responsible for digestive upsets. The large amount of indigestible fiber often causes “fiber” or “pear balls” while the high ash content most likely aggravates the scours as laxative effect. This appears to be as a result of the high levels of magnesium, potassium and sodium salts in the prickly pear (Griffiths and Hare, 1908). However, the scours can be reduced by increasing dry matter intake with lower quality feedstuffs (such as cottonseed hulls, hay, brush pasture).
Prickly pear is low in phosphorus and will meet a dry pregnant cow’s requirement usually only in the spring (Holloway and Varner, 1985). Since these cattle generally have the lowest phosphorus requirement, all other kinds and classes of cattle will require phosphorus supplementation year around. Prickly pear is very high in calcium (Griffiths and Hare, 1908; Hoffman and Darrow, 1964; Meyer and Brown, 1958) which further aggravates the calcium; phosphorus ratio imbalance seen on South Texas rangelands. A 12% calcium:12% phosphorus mineral mix (which can be easily consumed) should be used as a supplement for cattle fed prickly pear.
Prickly pear also appears to be very high in one other nutrient, often in limited quantities on drought prone rangelands and that is vitamin A. Vitamin A is supplied in natural feeds mainly by carotenoid precursors, and is found in large amounts in high quality green forages. These precursors are rapidly destroyed by exposure to sunlight and air and high temperatures. It is unknown exactly what level of vitamin A or carotenoid precursors exist in prickly pear cactus or what the effect of singeing the prickly pear has on vitamin A content.
Use of prickly pear as an emergency or sustenance feed during drought or hard winters is increasing in south Texas. During the winter of 1988-89, several ranchers who had not utilized prickly pear as a drought or supplemental forage called their county Extension agents and others concerned about singeing methods, the amount and the condition of the prickly pear to be fed. Many inquiries were also received after a hard freeze in early February 1989 when some ranchers were concerned about feeding pear that had been frozen. Griffiths (1905) reported that cattle would eat frozen, chopped prickly pear without any digestive problems. Experience with other ranchers indicates that there should be no concern with feeding prickly pear that has been frozen or frost damaged. These calls continue as ranchers look for ways to carry cattle through drought and freeze conditions.
Since most of the prickly pear in South Texas is of three species, it would be useful to have specific information on the effects of cold on the feeding quality. In the future, more work should be done on evaluating any potential differences in these species, methods of improving the cultivation of prickly pear, and in harvesting it.
Prickly pear is a good “hollow belly” cure and as an emergency feed ration it is an excellent natural resource to use in supplementing beef cattle. Prickly pear is highly variable in nutrient content depending on species and variety, age, class, season and plant part. Most of the research indicates that it is low in protein and phosphorus content but high in energy, water, fiber and ash. Most prickly pear rations will require additional supplementation of protein and phosphorus. Burning prickly pear is an effective way to utilize a ranch resource and to aid in maintaining cows in an emergency feed situation. There is a lack of current research evaluating prickly pear in South Texas, specifically as it relates to the ranch industry as a supplemental emergency feed in terms of ration formulation, feed methods and the economics of feeding.
Bath, D. L., J. R. Dunbar, J. M. King, S. L. Berry, R. O. Leonard and S. E. Olbrich. 1980. By-products and unusual feedstuffs in livestock rations. WREP No. 39, 22 pp.
Belasco, I. J., M. F. Gribbins and D. W. Kolterman. 1958. The response of rumen microorganisms to pasture grasses and prickly pear cactus following foliar application of urea. J. Anim. Sci. 17:209-217.
Correa, A., D. M. Nixon and C. Russell. 1987. An economic and nutritional evaluation of prickly pear on an emergency forage supplement. Texas J. Agr. And Nat. Res. 1:41-44.
Personal nutrient content in food plants of white-tailed deer on the South Texas Plains. J. Range. Manage. 34:(6)506-510.
Fraps, G. S. 1932. The composition and utilization of Texas feeding stuffs. Texas Agr. Exp. Sta. Bul. 461, 30 pp.
Gregory, R. A. 1988. Evaluation of prickly pear (Opuntia spp.) Cultivars for fruit, forage, and vegetable production in South Texas. M.S. Thesis, Texas A&I University, Kingsville, 124 pp.
Griffiths, D. 1905. The prickly pear and other cacti as food for stock. USDA Bureau of Plant Industries Bulletin, No. 74, 46 pp.
Griffiths, D. 1906. Feeding of prickly pear to stock in Texas. USDA Bureau of Animal Industries Bulletin, No. 91, 23 pp.
Griffiths, David and R. F. Hare. 1908. Prickly pear and other cacti as food for stock. New Mexico Agr. Exp. Sta. Bul. 60, 125 pp.
Hanselka, C. W. and J. C. Paschal. (Eds.) 1989. Developing prickly pear as a forage, fruit and vegetable resource. Proceedings of Conference, Texas A&I University, Kingsville, TX.
Hanselka, C. W. , J. C. Paschal and C. L. Richardson. 1991. South Texas ranching – A profile. South Texas Rangelands. Texas Agr. Ext. Ser. Bul. B-1050, 12 pp.
Hanselka, C. W. and L. Falconer. 1993. An economic assessment of pricklypear management in south Texas. In: Proceedings 4th Annual Prickly Pear Council, August 13th and 14th, 1993, Kingsville, TX.
Hoffman, G. O. And R. A. Darrow. 1964. Prickly pear . . . good or bad? Texas Agr. Ext. Ser. Bul. 806. 8 pp.
Holloway, J. W. And L. W. Varner. 1985. Meeting the nutrient requirements of beef cattle. In L. D. White, D. E. Guynn, and T. R. Troxel (Eds.) 1985 International Ranchers Roundup proceedings. pp. 276-285.
Meyer, M. W. And R. D. Brown. 1985. Seasonal trends in the chemical composition of ten range plants in South Texas. J. Range Manage. 38:(2)154-157.
Sawaya, W. N., J. K. Khalil and M. M. Al-Mohammed. 1983. Nutritive value of prickly pear seeds, Opuntia ficus-indica. Qual. Plant Foods Hum. Nutr. 33:91-97.
Shoop, M. C., E. J. Alford and M. F. Mayland. 1976. Plains prickly pear is good forage for cattle. J. Range. Manage. 30:(1)12-17.
Woodward, T. E. And W. F. Turner and David Griffiths. 1915. Prickly-pears as a feed for dairy cows. J. Agr. Res. 4:pp 405-451.