Nutrition of ruminant livestock grazing natural pasture, with special reference to supplementary phosphorus and sodium chloride – a South African perspective
DOI:
https://doi.org/10.17159/sajas.v55i10.06Keywords:
aphosphorosis, body mass, electrolyte balance, licks, reproduction, rib bone, subliminal thirstAbstract
South Africa has a long history of studying specific dietary deficiencies in livestock grazing natural pastures (veld), with these pastures generally regarded as deficient in protein and phosphorus. The pioneering work by Sir Arnold Theiler and co-workers focused on addressing the cause of bovine botulism, but a direct link to an underlying phosphorus deficiency was later established. Other minerals have also received attention in South Africa, but since the early 1900s, the focus has mainly been on the phosphorus nutrition of grazing ruminant livestock. The initial focus on a primary phosphorus deficiency evolved and became the catalyst for renewed and comprehensive studies at Armoedsvlakte and elsewhere in southern Africa. The information obtained from these studies improved the understanding of the important roles and interactions between the selective grazing behaviour of ruminants and the composition of the veld, which serves as their primary source of daily nutrient intake. Supplementing grazing ruminants with various minerals and rumen-stimulating licks became routine practice, but results have varied and expected animal performance has not always been attained. This review provides a perspective of the nutrition of ruminant livestock grazing veld, with reference to the role of supplementary feeding, especially of phosphorus and the ever-present sodium chloride. Reference is also made to arthrosis or osteochondrosis, a phenomenon observed in grazing cattle since 1982.
(Submitted 09 July 2025; Accepted 16 September 2025; Published 04 November 2025)
References
Baldwin, R.L., Smith, N.E., Taylor, J., & Sharp, M., 1980. Manipulating metabolic parameters to improve growth rate and milk secretion. Journal of Animal Science, 51:1416. DOI: https://doi.org/10.2527/jas1981.5161416x
Belonje, P.C., 1978. An investigation into possible methods of assessing the intake of calcium and phosphorus by grazing sheep. Onderstepoort Journal of Veterinary Research, 45:7–22.
Bisschop, J.H.R., 1964. Feeding phosphates to cattle. Department of Agricultural Technical Services Science Bulletin, 365:267.
Botha, F.K., 2018. The importance of minerals on the prevalence of osteochondrosis in cattle in southern Africa. MSc (Veterinary Science) thesis, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Pretoria.
Coetzee, C.G., 1969. Proteïenaanvulling op hoë en lae voedingspeile. Handelinge van die Suid-Afrikaanse Vereniging vir Diereproduksie, 8:43–48.
De Brouwer, C.H.M., Cilliers, J.W., Vermaak, L.M., Van der Merwe, H.J., & Groenewald, P.C.N., 2000. Phosphorus supplementation to natural grazing for beef cows in the Western Highveld region of South Africa. South African Journal of Animal Science, 30:43–52. DOI: https://doi.org/10.4314/sajas.v30i1.3875
De Waal, H.O., 1979. Die voedingswaarde van veldweiding van die sentrale Oranje-Vrystaat vir skape met spesiale verwysing na die rol van proteïen- en fosforaanvullings. MSc (Agric) thesis, University of Stellenbosch, South Africa.
De Waal, H.O., 1986. Die voedingswaarde van veldweiding van die sentrale Oranje-Vrystaat vir lakterende skape met spesiale verwysing na die rol van aanvullende energie en ruproteïen. PhD (Agric) thesis, University of Stellenbosch, South Africa.
De Waal, H.O., 1990. Animal production from native pasture (veld) in the Free State Region – A perspective of the grazing ruminant. South African Journal of Animal Science, 20:1–9.
De Waal, H.O., 1994. Effects of sodium chloride (salt) on grazing ruminants – A perspective. AFMA Matrix, 3(1):15–22.
De Waal, H.O., Baard, M.A., & Engels, E.A.N., 1989a. Effects of sodium chloride on sheep. 1. Diet composition, body mass changes and wool production of young Merino wethers grazing native pasture. South African Journal of Animal Science, 19:27–33.
De Waal, H.O., Baard, M.A., & Engels, E.A.N., 1989b. Effects of sodium chloride on sheep. 2. Voluntary feed intake and changes in certain rumen parameters of young Merino wethers grazing native pasture. South African Journal of Animal Science, 19:34–42.
De Waal, H.O. & Combrinck, W.J., 2000. The Dorper – its nutrition and a perspective of the grazing ruminant on veld. Small Ruminant Research, 36:103–117. DOI: https://doi.org/10.1016/S0921-4488(99)00155-8
De Waal, H.O., Combrinck, W.J., Howard, M.D., & Fouché, H.J., 2000. The impact of climate on veld (natural pasture or rangeland) and animal production. In: Proceedings of the Joint Zimbabwe Society for Animal Production (ZSAP)/Food and Agricultural Organization (FAO) Workshop on Strategies for Dry Season Feeding of Animals, 25–27 October 1999, Harare Club, Harare, Zimbabwe.
De Waal, H.O., Engels, E.A.N., & Biel, L.C., 1983. A note on the insertion of rumen cannulae in pregnant ewes. South African Journal of Animal Science, 13:264–265.
De Waal, H.O., Engels, E.A.N., & Van der Merwe, F.J., 1980. Supplementing sheep with protein and phosphorus on native pasture of the central Orange Free State. 1. Diet composition, digestibility and rumen ammonia concentration. South African Journal of Animal Science, 10:203–208.
De Waal, H.O., Engels, E.A.N., Van der Merwe, F.J., & Biel, L.C., 1981. Supplementing sheep with protein and phosphorus on native pasture of the central Orange Free State. 2. Feed intake, mass changes and wool production. South African Journal of Animal Science, 11:217–227.
De Waal, H.O. & Koekemoer, G.J., 1997. Blood, rib bone and rumen fluid as indicators of phosphorus status of grazing beef cows supplemented with different levels of phosphorus at Armoedsvlakte. South African Journal of Animal Science, 27:76–85.
De Waal, H.O., Randall, J.H., & Koekemoer, G.J., 1996. The effects of phosphorus supplementation on body mass and reproduction of grazing beef cows supplemented with different levels of phosphorus at Armoedsvlakte. South African Journal of Animal Science, 26:29–36.
Du Toit, P.J., Louw, J.G., & Malan, A.I., 1940. A study of the mineral content and feeding value of natural pastures in the Union of South Africa (final report). Onderstepoort Journal of Veterinary Science and Animal Industry, 14(1 & 2):123–327.
Drori, D., 1976. The effect of sodium chloride ingestion on food and fat deposition in male rats. British Journal of Nutrition, 35(2):195–200. DOI: https://doi.org/10.1079/BJN19760023
Engels, E.A.N., 1972. A study of the nutritive value of natural- and sown pasture in the central Orange Free State with special reference to the energy requirements of sheep. PhD·(Agric) thesis, University of Stellenbosch, South Africa.
Engels, E.A.N., 1981. Mineral status and profiles (blood, bone and milk) of the grazing ruminant with special reference to calcium, phosphorus and magnesium. South African Journal of Animal Science, 11:171–182.
Engels, E.A.N., Baard, M.A., & Malan, A., 1974a. Estimation of forage intake on pasture using faecal nitrogen concentration and in vivo digestibility results. Agroanimalia, 6:81–86.
Engels, E.A.N., De Waal, H.O., Biel, L.C., & Malan, A., 1981. Practical implications of the effect of drying and treatment on nitrogen content and in vitro digestibility of samples collected by oesophageally fistulated animals. South African Journal of Animal Science, 11:247–254.
Engels, E.A.N. & Malan, A., 1978. Die invloed van twee veebeladings op die samestelling van die dieet en inname van skape in 'n driekampstelsel in die sentrale Oranje-Vrystaat. Suid Afrikaanse Tydskrif vir Veekunde, 8:19–25.
Engels, E.A.N. & Malan, A., 1979. Feed intake of non-pregnant, pregnant and lactating ewes on native pasture and lucerne hay. South African Journal of Animal Science, 9:27–32.
Engels, E.A.N., Malan, A., & Baard, M.A., 1974b. The voluntary feed intake of three breeds of sheep on natural pasture. South African Journal of Animal Science, 4:27–29.
Engels, E.A.N., Van Schalkwyk, A., & Hugo, J.M., 1969. The determination of the nutritive value potential of natural pastures by means of an oesophageal fistula and faecal indicator technique. Agroanimalia, 1:119–122.
Engels, E.A.N., Van Schalkwyk, A., Malan, A., & Baard, M.A., 1971. The chemical composition and in vitro digestibility of forage samples selected by oesophageal fistulated sheep on natural pasture of the central Orange Free State. South African Journal of Animal Science, 1:43–44.
Faure, A.S., Minnaar, G.J., & Burger, F.J.L., 1983. The nutritive value of natural pasture in the Gordonia district. South African Journal of Animal Science, 13:116–119.
Faure, A.S., Minnaar, G.J., & Burger, F.J.L., 1985. Phosphorus supplementation of Karakul sheep grazing natural pasture. South African Journal of Animal Science, 15:33–37.
Groenewald, I.B., 1986. Die invloed van stikstof-, energie- en fosforbevattende lekaanvullings op die produksie- en reproduksievermoë van koeie op natuurlike weiding. PhD thesis, University of the Orange Free State, Bloemfontein, South Africa.
Hemingway, R.G., 1967. Phosphorus and the ruminant. Outlook on Agriculture, 5:172–180.
Little, D.A., 1972. Bone biopsy in cattle and sheep for studies of phosphorus status. Australian Veterinary Journal, 48:668–670. DOI: https://doi.org/10.1111/j.1751-0813.1972.tb09244.x
Little, D.A., McLean, R.W., & Winter, W.H., 1977. Prediction of the phosphorus content of herbage consumed by grazing cattle. The Journal of Agricultural Science, 88:533–538. DOI: https://doi.org/10.1017/S0021859600037217
Little, D.A. & Shaw, N.H., 1979. Superphosphate and stocking rate effect on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 5. Bone phosphorus levels in grazing cattle. Australian Journal of Experimental Agriculture and Animal Husbandry, 19:645–651. DOI: https://doi.org/10.1071/EA9790645
Lombard, P.E., 1966. Nutritional value of the pastures of the O.F.S. region for beef cattle production. DSc thesis, University of the Orange Free State, Bloemfontein, South Africa.
Louw, G.N., 1969. The nutritive value of natural grazing in South Africa. Proceedings of the South African Society of Animal Production, 8:57–62.
Louw, G.N., 1978. Die aanwending van voedselbronne vir diereproduksie. Suid Afrikaanse Tydskrif vir Veekunde, 8:79–84.
Louw, G.N., 1979. An evaluation of the application of stock licks in South Africa. South African Journal of Animal Science, 9:133–144.
McDonald, P., Edwards, R.A., Greenhalgh, J.F.D., Morgan, C.A., Sinclair, L.A., & Wilkinson, R.G., 2011. Animal Nutrition, 7th edition. Pearson Education Limited, Edinburgh Gate, Harlow, Essex CM20 2JE, England.
Meissner, H.H., Hofmeyr, H.S., Van Rensburg, W.J.J., & Pienaar, J.P., 1983. Classification of livestock for realistic prediction of substitution values in terms of a biologically defined Large Stock Unit. Department of Agriculture Technical Communication, No. 175:39, Pretoria, South Africa.
Meissner, H.H., Van Niekerk, W.A., Paulsmeier, D.V., & Henning, P.H., 1995. Ruminant nutrition research in South Africa during the decade 1985/1995. South African Journal of Animal Science, 25:118–131. DOI: https://hdl.handle.net/10520/EJC-1f03b9e81a
Prozesky, L., 2012. Wat is artrose? Vrae oor artrose. Boere Handleiding/Farmers’ Guide. Simbra Joernaal/Journal, 2012:99–100.
Prozesky, L., Neser, J., Meissner, H., Botha, K., Jacobs, L., Shepstone, C., Viljoen, H., Köster, H., De Brouwer, C., Van Zyl, J., & Van der Veen, G., 2016. Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa. Onderstepoort Journal of Veterinary Research, 83(1):a1083. DOI: http://dx.doi. org/10.4102/ojvr.v83i1.1083
Prozesky, L. & Shepstone, C., 2012. Arthrosis with lameness in cattle. Boere Handleiding/Farmers’ Guide. Simbra Joernaal/Journal, 2012:101–104.
Read, M.V.P., 1984. Animal performance from natural pastures and the effects of phosphorus supplementation. MSc (Agric) thesis, University of Stellenbosch, South Africa.
Read, M.V.P., Engels, E.A.N., & Smith, W.A., 1986a. Phosphorus and the grazing ruminant. 1. The effects of supplementary P on sheep at Armoedsvlakte. South African Journal of Animal Science, 16:1–6.
Read, M.V.P., Engels, E.A.N., & Smith, W.A., 1986b. Phosphorus and the grazing ruminant. 2. The effects of supplementary P on cattle at Glen and Armoedsvlakte. South African Journal of Animal Science, 16:7–12.
Read, M.V.P., Engels, E.A.N., & Smith, W.A., 1986c. Phosphorus and the grazing ruminant. 3. The rib bone sample as an indicator of the P status of cattle. South African Journal of Animal Science, 16:13–17.
Read, M.V.P., Engels, E.A.N., & Smith, W.A., 1986d. Phosphorus and the grazing ruminant. 4. Blood and faecal grab samples as indicators of the P status of cattle. South African Journal of Animal Science, 16:18–22.
Spangenberg, H.P., 1997. Phosphorus supplementation to grazing beef cows at two sites in the Northern Cape. PhD thesis, University of the Orange Free State, Bloemfontein, South Africa.
Theiler, A., 1912. Facts and theories about stÿfziekte and lamziekte. Second Report of the Director of Veterinary Research, 7–78. URI: http://hdl.handle.net/2263/13245
Theiler, A., Viljoen, P.R., Green, H.H., Du Toit, P.J., Meier, H., & Robinson, E.M., 1927. Lamsiekte (Parabotulism) in cattle in South Africa. 11th and 12th Reports of the Director of Veterinary Education and Research, 821.
Theiler, A. & Green, H.H., 1932. Aphosphorosis in ruminants. Nutritional Abstracts and Reviews, 1:359–385.
Underwood, E.J. & Suttle, N.F., 1999. The Mineral Nutrition of Livestock, 3rd edition. CAB International Publishing, UK.
Van der Merwe, F.J., 1974. Nuutste ontwikkelinge in kennis oor die mineraalmetabolisme en mineraalversorging van herkouers. South African Journal of Animal Science, 4:271–274.
Van der Merwe, F.J., 1985. Dierevoeding. Kosmo-Uitgewery, Stellenbosch.
Van der Merwe, F.J. & Perold, I.S., 1967. Trace elements in natural pastures. Journal of the South African Veterinary Association, 38:355–363.
Van der Veen, G., Fosgate, G.T., Botha, F.K., Meissner, H.H., Jacobs, L., & Prozesky, L., 2017. Response of cattle with clinical osteochondrosis to mineral supplementation. Onderstepoort Journal of Veterinary Research, 84(1):a1365. DOI: https://doi. org/10.4102/ojvr.v84i1.1365
Van Niekerk, B.D.H., 1996. Limiting nutrients in supplementary feeding. Bulletin of the Grassland Society of Southern Africa, 7(1):51–62.
Van Niekerk, B.D.H. & Jacobs, G.A., 1985. Protein, energy and phosphorus supplementation of cattle fed low-quality forage. South African Journal of Animal Science, 15(4):133–136.
Van Schalkwyk, A., Lombard, P.E., & Vorster, L.F., 1968. Evaluation of the nutritive value of a Themeda triandra pasture in the central O.F.S. II. Comparison between quadrat and simulated grazing samples. South African Journal of Agricultural Science, 11:249–258.
Ward, H.K., 1968. Supplementation of beef cows grazing on veld. Rhodesian Journal of Agricultural Research, 6:93.
Wessels, T.C., 1999. Phosphorus supplementation to grazing beef cows in the Molopo region (Saratoga) of the North-West Province. MSc (Agric) dissertation, University of the Free State, Bloemfontein, South Africa.
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