Hostname: page-component-848d4c4894-ndmmz Total loading time: 0 Render date: 2024-06-08T08:14:12.989Z Has data issue: false hasContentIssue false

Phosphorus kinetics of cattle grazing tropical pastures and implications for the estimation of their phosphorus requirements

Published online by Cambridge University Press:  27 March 2009

D. B. Coates
Affiliation:
Division of Tropical Crops and Pastures, CSIRO, PMB, PO Aitkenvale, Townsville, Qld. 4814, Australia
J. H. Ternouth
Affiliation:
Department of Agriculture, The University of Queensland, Brisbane, Qld, 4072, Australia

Summary

Twelve yearling Droughtmaster heifers were grazed on a tropical grass/legume pasture in north-east Australia for 1 year in four paddocks, each of 4 ha. One paddock was fertilized annually with 10 kg P/ha (treatment HPF). The other three paddocks had low soil P and low pasture P status. In one of the low soil P paddocks, P was added to the drinking water (treatment HPS) but no supplement was provided in the other two paddocks (treatments LP1 and LP2). In February, May and August 1989, the P kinetics of the heifers were monitored following oral administration of ruminal chromic oxide capsules and i/v injection of 32P. At the same times, oesophageal-fistulated steers were grazed in the paddocks to obtain extrusa samples to estimate the P content and digestibility of selected forage.

The liveweight gain per heifer was higher in the HP treatments (196 kg) than in the LP treatments (152 kg). The intake, absorption and excretion of P were closely related but the faecal excretion of P relative to P intake was less in heifers with than without P supplement. The P intakes of the LP heifers were about half the quantities recommended in the nutrient feeding standards for the observed food intakes and weight gains. The coefficients of P absorption in the LP heifers in May and August were high (> 0·8) and did not decrease with age or liveweight. The coefficients of P absorption of heifers given supplementary P were as high as those for LP heifers, but those of heifers on the fertilized pasture were significantly lower in May and August. The endogenous faecal excretion of P was related to P intake but more closely to dry matter intake and plasma inorganic P together. The reasons for the difference between observed P intakes of LP heifers and recommended requirements are discussed in relation to the assessment of P requirements of grazing cattle. The results from this experiment suggest that recommended P requirements are higher than necessary to sustain the measured liveweight gains of cattle on grass/legume pastures in the tropics.

Type
Animals
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Agricultural Research Council (1980). The Nutrient Requirements of Ruminant Livestock. Slough: Commonwealth Agricultural Bureaux.Google Scholar
Boxebeld, A., Guéguen, L., Hannequart, G. & Durand, M. (1983). Utilization of phosphorus and calcium and minimal maintenance requirement for phosphorus in growing sheep fed a low-phosphorus diet. Reproduction, Nutrition, Développement 23, 10431053.CrossRefGoogle Scholar
Braithwaite, G. D. (1983). Calcium and phosphorus requirements of the ewe during pregnancy and lactation. 2. Phosphorus. British Journal of Nutrition 50, 723736.Google Scholar
Braithwaite, G. D. (1984). Some observations on phosphorus homoeostasis and requirements of sheep. Journal of Agricultural Science, Cambridge 102, 295306.Google Scholar
Braithwaite, G. D. (1985). Endogenous faecal loss of phosphorus in growing lambs and the calculation of phosphorus requirements. Journal of Agricultural Science, Cambridge 105, 6772.Google Scholar
Braithwaite, G. D. (1986). Phosphorus requirements of ewes in pregnancy and lactation. Journal of Agricultural Science, Cambridge 106, 271278.Google Scholar
Call, J. W., Butcher, J. E., Shupe, J. L., Blake, J. T. & Olson, A. E. (1986). Dietary phosphorus for beef cattle. American Journal of Veterinary Research 47, 475481.Google Scholar
Challa, J., Braithwaite, G. D. & Dhanoa, M. S. (1989). Phosphorus homoeostasis in growing calves. Journal of Agricultural Science, Cambridge 112, 217226.Google Scholar
Coates, D. B. (1987). Effect of phosphorus as fertilizer or supplement on the liveweight gain of cattle grazing stylo pastures. In Herbivore Nutrition Research – Research Papers presented at the Second International Symposium on The Nutrition of Herbivores (Ed. M., Rose), pp. 213214. An occasional publication of the Australian Society of Animal Production.Google Scholar
Cook, S. J. & Russell, J. S. (1983). The climate of seven CSIRO field stations in northern Australia. Division of Tropical Crops and Pastures, CSIRO, Australia. Technical Paper No. 25.Google Scholar
Costigan, P. & Ellis, K. J. (1987). Analysis of faecal chromium derived from controlled release marker devices. New Zealand Journal of Technology 3, 8992.Google Scholar
Field, A. C., Woolliams, J. A. & Dingwall, R. A. (1985). Phosphorus kinetics in cattle The effect of dietary intake of calcium and dry matter on the absorption and excretion of calcium and phosphorus by growing lambs. Journal of Agricultural Science, Cambridge 105, 237243.Google Scholar
Geay, Y. & Micol, D. (1989). Growing and finishing cattle. In Ruminant Nutrition (Ed. R., Jarrige), pp. 121151. London: Libley.Google Scholar
Guéguen, L., Lamand, M. & Meschy, F. (1989). Mineral requirements. In Ruminant Nutrition (Ed. R., Jarrige), pp. 4953. London: Libley.Google Scholar
Little, D. A. (1970). Factors of importance in the phosphorus nutrition of beef cattle in northern Australia. Australian Veterinary Journal 46, 241248.CrossRefGoogle ScholarPubMed
Little, D. A. (1972). Bone biopsy in cattle and sheep for studies of phosphorus status. Australian Veterinary Journal 48, 668670.CrossRefGoogle ScholarPubMed
Little, D. A. (1980). Observations on the phosphorus requirements of cattle for growth. Research in Velerinarv Science 28, 258260.Google Scholar
Little, D. A. (1983). Bovine body composition and phosphorus storage. PhD thesis, University of Queensland.Google Scholar
Little, D. A. (1984). Definition of an objective criterion of body phosphorus reserves in cattle and its evaluation in vivo. Canadian Journal of Animal Science 64 (Supplement), 229231.CrossRefGoogle Scholar
Little, D. A., Mclean, R. W. & Winter, W. H. (1977). Prediction of the phosphorus content of herbage consumed by grazing cattle. Journal of Agricultural Science, Cambridge 88, 533538.CrossRefGoogle Scholar
Mcleod, M. N. & Minson, D. J. (1978). The accuracy of the pepsin-cellulase technique for estimating the dry matter digestibility in vivo of grasses and legumes. Animal Feed Science and Technology 3, 277—287.Google Scholar
Minson, D. J. & Mcdonald, C. K. (1987). Estimating forage intake from the growth of beef cattle. Tropical Grasslands 212, 116122.Google Scholar
National Research Council (1984). Nutrient Requirements of Domestic Animals. Nutrient Requirements of Beef Cattle. Washington: National Academy of Sciences.Google Scholar
Read, M. V. P., Engels, E. A. N. & Smith, W. A. (1986 a). Phosphorus and the grazing ruminant. 1. The effect of supplementary P on sheep at Armoedsvlakte. South African Journal of Animal Science 16, 16.Google Scholar
Read, M. V. P., Engels, E. A.N. & Smith, W. A. (1986 b). Phosphorus and the grazing ruminant. 2. The effects of supplementary P on cattle at Glen and Armoedsvlakte. South African Journal of Animal Science 16, 712.Google Scholar
Scott, D. & Buchan, W. (1985). The effects of feeding either roughage or concentrate diets on salivary phosphorus secretion, net intestinal phosphorus absorption and urinary phosphorus excretion in the sheep. Quarterly Journal of Experimental Physiology 70, 365375.Google Scholar
Scott, D. & Buchan, W. (1987). The effects of feeding either hay or grass diets on salivary phosphorus secretion, net intestinal phosphorus absorption and on the partition of phosphorus excretion between urine and faeces in the sheep. Quarterly Journal of Experimental Physiology 72, 331338.Google Scholar
Scott, D. & Buchan, W. (1988). The effects of feeding pelleted diets made from either coarsely or finely ground hay on phosphorus balance and on the partition of phosphorus excretion between faeces and urine in the sheep. Quarterly Journal of Experimental Physiology 73, 315322.Google Scholar
Scott, D., Whitelaw, F. G., Buchan, W. & Bruce, L. A. (1985). The effect of variation in phosphorus intake on salivary phosphorus secretion, net intestinal phosphorus absorption and faecal endogenous phosphorus excretion in sheep. Journal of Agricultural Science, Cambridge 105, 271277.Google Scholar
Standing Committee On Agriculture (1990). Feeding Standards for Australian Livestock. Ruminants. Melbourne: Commonwealth Scientific and Industrial Research Organisation.Google Scholar
Ternouth, J. H. (1989). Endogenous losses of phosphorus by sheep. Journal of Agricultural Science, Cambridge 113, 291297.Google Scholar
Ternouth, J. H., Mclean, R. W., Macdonald, R. N. & Adamu, A. (1990). Field estimates of the phosphorus kinetics of grazing cattle. Animal Production in Australia 18, 396399.Google Scholar
Tothill, J. C., Hargreaves, J. N. C. & Jones, R. M. (1978). BOTANAL – A comprehensive sampling and computer procedure for estimating pasture yield and composition. 1. Field sampling. Division of Tropical Crops and Pastures, CS1RO, Australia. Technical Memorandum No. 8.Google Scholar
Tuen, A. A., Wadsworth, J. C. & Murray, M. (1984). Absorption of calcium and phosphorus by growing cattle during dietary protein deficiency. Proceedings of the Nutrition Society of Australia 9, 144148.Google Scholar
Wadsworth, J. C., Mclean, R. W., Coates, D. B. & Winter, W. H. (1990). Phosphorus and beef production in northern Australia. 5. Animal phosphorus status and diagnosis. Tropical Grasslands 24, 185196.Google Scholar
Winks, L. (1990). Responses to phosphorus by ruminants – a review. Tropical Grasslands 24, 140158.Google Scholar
Winter, W. H., Coates, D. B., Kerridge, P. C. & Miller, C. P. (1990). Phosphorus and beef production in northern Australia. 4. The response of cattle to fertilizer and supplementary phosphorus. Tropical Grasslands 24, 170184.Google Scholar