Chapters 5.28
5.28 -Adopting a combination of spineless cactus and saltbush as sheep fodder to combat drought
Madeline Cherevaty, University of Guelph, Canada
Suggested citation for this chapter.
Cherevaty,M. (2022) Adopting a combination of spineless cactus and saltbush as sheep fodder to combat drought, In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. http://www.farmpedia.org
An Introduction to Climate Change
Africa is known for its varying land aridity, an increasing population, harsh climate and abundance of water scarcity. Each day that passes, vegetation is continually lost due to the lack of hydration and the progression of climate change. African smallholder farmers would greatly benefit from the introduction of new, drought-tolerant and climate change mitigation practices (Challinor, Andrew, et al. 2007). Research has shown that by the year 2050, crop yield in Africa is set to reduce by a minimum of 10-20%, with a high risk of more extreme cases of loss, which has led to the suggestion that smallholder farmers should keep more livestock instead of focusing solely on cropping (Jones et al, 2009).
An Easy Accessible Solution
The combined use of spineless cactus (Opuntia ficus) and saltbush (Atriplex halimus) as fodder for sheep is a drought-tolerant, multipurpose practice that has been shown to be both efficient and easily accessible for smallholder farmers. This method has been used for many years within the southwestern United States, and has become a major staple crop for livestock within Mexico, (Russell and Felker, 1987). The sheep population in East Africa alone is roughly 0.5 sheep per person living within these areas, which equates to about 8% of the total domestic livestock in those nations (Wilson, 1991). This drought tolerant method however, does work with other domesticated animals such as cattle and goats (Syomiti, et al. 2009). Farmers are able to grow spineless cactus within these semiarid or arid land areas which would allow them to harvest the fruit for human consumption while also harvesting the stems to be used for fodder. The combination of these crops for feed combats the problems that come from using just one of these crops individually. These stems contain high volumes of carbohydrates, vitamin A and calcium, with saltbush containing the fiber and protein that spineless cactus lacks. The textures and moisture contents of both of these crops complement each other out and provide strong water use efficiency, which provides farmers with the ability to save freshwater for other basic needs (Alhanafi et al.,2019)
Nutrient Content
The nutrient composition of spineless cactus can vary depending on the variety and country of origin. On average, however, the cladodes have the highest percentage of ash, nitrogen, crude protein and crude fibre (De Kock, 1965). The average levels of each chemical are as follows: ash is 17.19%, crude protein is 4.76%, crude fibre is 10.91% and nitrogen is 65.3% (Nefzaoui, et al., 2000). For amino acids, the highest percentages belong to glutamic acid at 12.88%, aspartic acid at 9.12%, and alanine at 8.19% (Salem, et al., 2000). For saltbush, the chemical composition is based on the time of year, however, during dry periods, concentrations were noticed to decrease. Major nutrients in saltbush include fibre, crude protein, phosphorus, calcium and nitrogen (Moh'D, et al., 2000).
The Production of Spineless Cactus
Spineless cactus is an evergreen crop commonly used within drought-prone land areas due to its high-water use efficiency and productive performance on dry soils (Walker, et al., 2014). Most commonly, these cacti are grown by placing trimmings of the leaf pads into the soil, however, pads can also be planted in furrows, alongside fertilizer, natural or synthetic, though with the use of natural fertilizer lower amounts of water are needed to obtain a higher yield. Roots develop within a few weeks after planting, and plants can be partly harvested, or leaves can be trimmed (as needed, however, it is suggested to harvest completely after 2 or 3 years, (Ben Salem, H., Nefzaoui, A., 2000). The moisture content of spineless cacti is around 90%, which also decreases the need to have freshwater available for livestock during times of serious drought, with research showing a 2.3 L decrease in the daily volume of water consumed by livestock; furthermore, along with the use of furrows to reduce rainfall-runoff, both crops improve sustainability for communities with low rainfall (Terblanche, IL, Mulder, AM, & Rossouw, 1971).
The Production of Saltbush
Saltbushes are perennial and can live for multiple decades, have little to no pest and disease issues and can be grown from seed or transplants (Walker et al., 2014). Within Africa, it is recommended to plant this crop with the furrow methods used to plant cereals which matches the methods used to plant spineless cactus. Foliage should be cut to allow for a quicker regrowth and to maintain a higher protein content (Walker et al., 2014). The use of alternating crop furrows or alley cropping is especially efficient because it allows for constraints to be overcome that may cause weak yields; some of these constraints include weed management, soil fertility and water runoff. Studies have also shown the use of saltbush to draw out salt from within soils, thus allowing the use of this crop to improve the quality and stability of the soil (Le Houérou, 1992).
The Overall Benefit vs Cost Analysis
Introducing this new diet to a group of livestock is a cost-effective strategy. Cactus alone can produce up to 20 tonnes of viable feed per hectare per year, which is able to produce enough feed to sustain about 5 large livestock a year. The typical price of beginning this practice would range from around $300 to $200 US per hectare for the first three years depending on the density of crops the farmer would desire based on the amount of livestock they need to feed. Also, this method of cheap feed would lack the extra required labour that is needed with other feed crops, (Inglese, Paolo, et al., 2000). This is due to the lack of care needed during the growing periods, where the only maintenance needed between harvests is the trimming of foliage to allow for larger and faster growth (Nefzaoui, Ali., 1996). The costs of this drought-tolerant technique may appear expensive but with the consideration of everything that is gained from the use of the crops, such as decreased water usage, evergreen/perennial life, ability to sell on local market places and the decrease in labour needed to maintain the crops, the price of establishing this new idea becomes more understandable (Inglese, Paolo, et al., 2000).
Insight into the Negatives
Though the positive benefits of these two crops as sheep fodder are extensive, there are also potential negative impacts of this practice. One negative impact that may arise is the overuse of the cactus within the mix of these crops given to the animals in question. The high moisture content among other contents within the cacti are known to be a severe laxative and would result in a quicker cycle through the digestive system, however, this natural laxative is not harmful to the health of any livestock and can be counterbalanced with multiple solutions. A few of these solutions are to use lime within the mix, increase the ration of saltbush to cacti, or limit access to water (Ben Salem, H., Nefzaoui, A, 200). Another negative result of this method can be the cost of establishing these crops as subsidies may be required, or the cost of accessibility within different countries. This problem is most accurately shown within the country of Tunisia where the cost of the first 3 years of all the maintenance, subsidies, along with the cost of establishment is around $750 US/Ha for spineless cactus and around $1000 US/Ha for saltbush (Nefzaoui, Ali. 1996). The last potential downfall of the use of spineless cactus and saltbush is the risks of disease specifically in spineless cactus. The main enemy is fungi normally stemming from rainy seasons or exposure to already infected crops but can be managed with the use of fungicides and the removal or infected stems (Inglese, Paolo, et al., 2000)
Links to Useful Resources
http://www.fao.org/ag/aga/agap/frg/conf96.htm/nefzaoui.htm - Link to FAO article about the use of this method
https://www.researchgate.net/publication/331523329_Spineless_cactus_Opuntia_ficus-indica_and_saltbush_Atriplex_halimus_L_as_feed_supplements_for_fattening_Awassi_male_lambs_effect_on_digestibility_water_consumption_blood_metabolites_and_growth_perform - Link to research done to show how the use of different ratios of cacti to bush works for fattening lambs.
http://www.fao.org/3/a-i7012e.pdf PDF full of extensive research on Opuntia and its biology http://www.fao.org/3/Y2808E/y2808e0d.htm - Link to further details of amino acid and nutritional content
https://www.youtube.com/watch?v=NHP0WFz0-s4 - Video providing explanation of cactus crop integration
https://www.youtube.com/watch?v=gLm2Q3-qdMs - Example of using method on cattle
https://www.growplants.org/growing/saltbush - Link to video and advice for growing saltbush
https://homeguides.sfgate.com/transplant-spineless-cactus-33204.html - Step by step guide to growing spineless cactus
References
1. Alhanafi, F., Kaysi, Y., Muna, M. et al. (2019) Spineless cactus (Opuntia ficus-indica) and saltbush (Atriplex halimus L.) as feed supplements for fattening Awassi male lambs: effect on digestibility, water consumption, blood metabolites, and growth performance. Trop Anim Health Prod 51: 1637. https://doi-org.subzero.lib.uoguelph.ca/10.1007/s11250-019-01858-6
2. Ben Salem, H., Nefzaoui, A., & Ben Salem, L. (2000, October). Opuntia ficus-indica f. inermis and Atriplex nummularia L.: Two complementary fodder shrubs for sheep and goats. In IV International Congress on Cactus Pear and Cochineal, Hammamet, Tunisia 581 (pp. 333-341).
3. Challinor, A., et al. (2007) Assessing the vulnerability of food crop systems in Africa to climate change. Climatic Change 83:381-399.
4. De Kock, G. C. (n.d.). The use of Opuntia as a fodder source in arid areas of Southern Africa. FAO, Rome. Retrieved October 2, 2019, from http://www.fao.org/3/Y2808E/y2808e0f.htm.
5. El‐Shatnawi, M. D. K. J., & Turuk, M. (2002). Dry matter accumulation and chemical content of saltbush (Atriplex halimus) grown in Mediterranean desert shrublands. New Zealand Journal of Agricultural Research, 45(3), 139-144.
6. Inglese, Paolo, et al. 2017. Crop ecology, cultivation and uses of cactus pear. Food and Agriculture Organization of the United Nations (FAO). 2017. http://www.fao.org/3/a-i7012e.pdf
7. Jones, P.G., and P.K. Thornton. (2009) Croppers to livestock keepers: livelihood transitions to 2050 in Africa due to climate change. Environmental Science & Policy 12:4 : 427-437. https://doi.org/10.1016/j.envsci.2008.08.006
8. Le Houérou, H. N. (1992) The role of saltbushes (Atriplex spp.) in arid land rehabilitation in the Mediterranean Basin: a review. Agroforestry Systems 18:2: 107-148. http://agris.fao.org/agris-search/search.do?recordID=NL19920062822
9. Misra, A. K., Mishra, A. S., Tripathi, M. K., Chaturvedi, O. H., Vaithiyanathan, S., Prasad, R., & Jakhmola, R. C. (2006). Intake, digestion and microbial protein synthesis in sheep on hay supplemented with prickly pear cactus [Opuntia ficus-indica (L.) Mill.] with or without groundnut meal. Small Ruminant Research, 63(1-2), 125-134.
10. Moh'D Khair, J. El-Shatnawi, & Yaser M. Mohawesh. (2000). Seasonal Chemical Composition of Saltbush in Semiarid Grasslands of Jordan. Journal of Range Management, 53(2), 211-214. doi:10.2307/4003285
11. Nefzaoui, Ali. (1996). The Integration of Fodder Shrubs and Cactus in the Feeding of Small Ruminants in the Arid Zones of North Africa. FAO. http://www.fao.org/ag/aga/agap/frg/conf96.htm/nefzaoui.htm
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13. Russell, Charles E., and Peter Felker. (1987) The prickly-pears (Opuntia spp., Cactaceae): a source of human and animal food in semiarid regions. Economic Botany 41:3 : 433-445.
14. Sáenz, C., & al, et. (2013). Agro-industrial utilization of cactus pear, 1:186. FAO, Rome. Retrieved from http://www.fao.org/3/a0534e/a0534e.pdf
15. Salem, H. B., Nefzaoui, A., & Salem, L. B. (2004). Spineless cactus (Opuntia ficus indica f. inermis) and Oldman saltbush (Atriplex nummularia L.) as alternative supplements for growing Barbarine lambs given straw-based diets. Small Ruminant Research, 51(1), 65:73.
16. Syomiti, M., Chirchir, S., Duyu, J., & Dana, H. (2009) Feeding spineless cactus to cattle for drought resilience, Kenya. FAO. http://www.fao.org/fileadmin/user_upload/nr/sustainability_pathways/docs/Feeding%20spineless%20cactus%20to%20%20cattle%20for%20drought%20%20resilience%20Kenya.pdf
17. Terblanche, IL, Mulder, AM, & Rossouw, JW 1971. The influence of moisture content on dry matter intake and digestibility of spineless cactus. Agro-animal, (2): 73:77.
18. Walker, D. J., et al. (2014) Atriplex halimus L.: Its biology and uses. Journal of Arid Environments 100:121.
19. Wilson, R. T. (1991). Small ruminant production and the small ruminant genetic resource in tropical Africa (No. 88). Food & Agriculture Organization, Rome. http://www.fao.org/3/t0376e/t0376e00.htm