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Journal of the Australian Rangeland Society
RESEARCH ARTICLE (Open Access)

Diet quality, liveweight change and responses to N supplements by cattle grazing Astrebla spp. (Mitchell grass) pastures in the semi-arid tropics in north-western Queensland, Australia

R. M. Dixon A * , M. T. Sullivan B , S. N. O’Connor B D and R. J. Mayer C
+ Author Affiliations
- Author Affiliations

A The University of Queensland, QAAFI, St Lucia, Qld 4072, Australia.

B Department of Agriculture and Fisheries, Rockhampton, Qld 4701, Australia.

C Department of Agriculture and Fisheries, Maroochy Research Facility, Qld 4560, Australia.

D Present address: Bostan, Tambo, Qld 4478, Australia.

* Correspondence to: r.dixon2@uq.edu.au

The Rangeland Journal 44(2) 97-113 https://doi.org/10.1071/RJ21056
Submitted: 17 November 2021  Accepted: 7 May 2022   Published: 23 June 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Australian Rangeland Society. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Experiments during 4 years examined the diets selected, growth, and responses to N supplements by Bos indicus-cross steers grazing summer-rainfall semi-arid C4 Astrebla spp. (Mitchell grass) rangelands at a site in north-western Queensland, Australia. Paddock groups of steers were not supplemented (T-NIL), or were fed a non-protein N (T-NPN) or a cottonseed meal (T-CSM) supplement. In Experiment 1, young and older steers were measured during the late dry season (LDS) and the rainy season (RS), while steers in Experiments 2–4 were measured through the annual cycle. Because of severe drought the measurements during Experiment 3 annual cycle were limited to T-NIL steers. Pasture availability and species composition were measured twice annually. Diet was measured at 1–2 week intervals using near infrared spectroscopy of faeces (F.NIRS). Annual rainfalls (1 July–30 June) were 42–68% of the long-term average (471 mm), and the seasonal break ranged from 17 December to 3 March. There was wide variation in pasture, diet (crude protein (CP), DM digestibility (DMD), the CP to metabolisable energy (CP/ME) ratio) and steer liveweight change (LWC) within and between annual cycles. High diet quality and steer liveweight (LW) gain during the RS declined progressively through the transition season (TS) and early dry season (EDS), and often the first part of the LDS. Steers commenced losing LW as the LDS progressed. In Experiments 1 and 2 where forbs comprised ≤15 g/kg of the pasture sward, steers selected strongly for forbs so that they comprised 117–236 g/kg of the diet. However, in Experiments 3 and 4 where forbs comprised substantial proportions of the pasture (173–397 g/kg), there were comparable proportions in the diet (300–396 g/kg). With appropriate stocking rates the annual steer LW gains were acceptable (121–220 kg) despite the low rainfall. The N supplements had no effect on steer LW during the TS and the EDS, but usually reduced steer LW loss by 20–30 kg during the LDS. Thus during low rainfall years in Mitchell grass pastures there were substantial LW responses by steers to N supplements towards the end of the dry season when the diet contained c. <58 g CP/kg or c. <7.0 g CP/MJ ME.

Keywords: dietary protein, digestibility, faeces, forbs, grazing, near infrared spectroscopy, protein supplements, rangelands, steers.


References

Blake, ST (1938). The plant communities of Western Queensland and their relationships, with special reference to the grazing industry. Proceedings of the Royal Society of Queensland 49, 156–204.

Bortolussi, G, McIvor, JG, Hodgkinson, JJ, Coffey, SG, and Holmes, CR (2005). The northern Australian beef industry, a snapshot. 3. Annual liveweight gains from pasture based systems. Australian Journal of Experimental Agriculture 45, 1093–1108.
The northern Australian beef industry, a snapshot. 3. Annual liveweight gains from pasture based systems.Crossref | GoogleScholarGoogle Scholar |

Christian CS, Noakes LC, Perry RA, Slatyer RO, Stewart GA, Traves DM (1952) ‘Survey of the Barkly region, Northern Territory and Queensland, 1947-48. Land Series 3.’ (CSIRO: Melbourne, Vic., Australia)

Coates DB (2004) Faecal NIRS – Technology for improving nutritional management of grazing cattle. Final Report of Project NAP3.121. Meat and Livestock Australia, Sydney, NSW, Australia.

Coates, DB, and Dixon, RM (2007). Faecal near infrared reflectance spectroscopy (F.NIRS) measurements of non-grass proportions in the diet of cattle grazing tropical rangelands. The Rangeland Journal 29, 51–63.
Faecal near infrared reflectance spectroscopy (F.NIRS) measurements of non-grass proportions in the diet of cattle grazing tropical rangelands.Crossref | GoogleScholarGoogle Scholar |

Coates, DB, and Dixon, RM (2008a). Faecal near infrared reflectance spectroscopy measurements of diet quality and responses to N supplements by cattle grazing Bothriochloa pertusa pastures. Australian Journal of Experimental Agriculture 48, 829–834.
Faecal near infrared reflectance spectroscopy measurements of diet quality and responses to N supplements by cattle grazing Bothriochloa pertusa pastures.Crossref | GoogleScholarGoogle Scholar |

Coates, DB, and Dixon, RM (2008b). Development of NIRS analysis of faeces to estimate non-grass proportions in the diets selected by cattle grazing tropical pastures. Journal of Near Infrared Spectroscopy 16, 471–480.
Development of NIRS analysis of faeces to estimate non-grass proportions in the diets selected by cattle grazing tropical pastures.Crossref | GoogleScholarGoogle Scholar |

Coates, DB, and Dixon, RM (2011). Developing robust faecal NIRS calibrations to predict diet dry matter digestibility in cattle consuming tropical forages. Journal of Near Infrared Spectroscopy 19, 507–519.
Developing robust faecal NIRS calibrations to predict diet dry matter digestibility in cattle consuming tropical forages.Crossref | GoogleScholarGoogle Scholar |

Cobon, DH, and Carter, JO (1994). Effect of herbage in Astrebla spp. pastures in north-west Queensland on lamb survival. Journal of Agricultural Science, Cambridge 122, 291–298.
Effect of herbage in Astrebla spp. pastures in north-west Queensland on lamb survival.Crossref | GoogleScholarGoogle Scholar |

Cowley R, Scott K, Kraft P, Hearnden M (2018) Newcastle Waters grazing trial: Comparing cell grazing systems with traditional practice in the north-western Barkly region. Northern Territory Government. Technical Bulletin number 357. Darwin, NT, Australia.

CSIRO (2007) ‘Nutrient requirements of domesticated ruminants’, (CSIRO Publishing: Melbourne, Vic., Australia)

Cunningham GM, Mulham WE, Milthorpe PL, Leigh JH (1981) ‘Plants of Western New South Wales’, (Soil Conservation Service of New South Wales: Sydney, NSW, Australia)

Davies, JG, Scott, AE, and Kennedy, JF (1938). The yield and composition of Mitchell grass pasture for a period of twelve months. Journal of the CSIR 11, 127–139.

Dixon RM (1998) Improving cost-effectiveness of supplementation systems for breeder herds in northern Australia. Final Report DAQ.098. Meat and Livestock Australia, Sydney, NSW, Australia.

Dixon RM (2008) Utilizing faecal NIRS measurements to improve prediction of grower and breeder cattle performance and supplement management. Final Report of Project NBP.302. Meat and Livestock Australia, Sydney, NSW, Australia.

Dixon, RM, and Coates, DB (2005). The use of faecal NIRS to improve nutritional management of cattle in northern Australia. Recent Advances in Animal Nutrition in Australia 15, 65–75.

Dixon, RM, and Coates, DB (2008). Diet quality and liveweight gain of steers grazing Leucaena-grass pasture estimated with near infrared reflectance spectroscopy. Australian Journal of Experimental Agriculture 48, 835–842.
Diet quality and liveweight gain of steers grazing Leucaena-grass pasture estimated with near infrared reflectance spectroscopy.Crossref | GoogleScholarGoogle Scholar |

Dixon, RM, and Coates, DB (2009). NIR spectroscopy of faeces to evaluate the nutrition and physiology of herbivores: a review. Journal of Near Infrared Spectroscopy 17, 1–31.
NIR spectroscopy of faeces to evaluate the nutrition and physiology of herbivores: a review.Crossref | GoogleScholarGoogle Scholar |

Dixon, RM, and Coates, DB (2010). Diet quality estimated with near infrared reflectance spectroscopy (F.NIRS) and responses to N supplementation by cattle grazing buffel grass pastures. Animal Feed Science and Technology 158, 115–125.
Diet quality estimated with near infrared reflectance spectroscopy (F.NIRS) and responses to N supplementation by cattle grazing buffel grass pastures.Crossref | GoogleScholarGoogle Scholar |

Dixon, R M, and Egan, AR (2000). Response of lambs fed low quality roughage to supplements based on urea, cereal grain, or protein meals. Australian Journal of Agricultural Research 51, 811–821.
Response of lambs fed low quality roughage to supplements based on urea, cereal grain, or protein meals.Crossref | GoogleScholarGoogle Scholar |

Dixon, RM, and Mayer, RJ (2021). Effects of a nitrogen-based supplement on intake, liveweight and body energy reserves in breeding Bos indicus cross cows. Tropical Grasslands – Forrajes Tropicales 9, 70–80.
Effects of a nitrogen-based supplement on intake, liveweight and body energy reserves in breeding Bos indicus cross cows.Crossref | GoogleScholarGoogle Scholar |

Dixon RM, Hamlyn-Hill F, Cribb R, McClymont A, Coates DB (2007a) Faecal NIRS measurements of the diet quality and growth of cattle grazing Mitchell grass–forest country pastures near Richmond, N Qld. In ‘Northern Beef Research Update Conference’, Townsville, Qld, Australia, 21–22 March 2007.

Dixon, RM, Smith, DR, and Coates, DB (2007b). Using faecal NIRS to improve nutritional management of breeders in the seasonally dry tropics. Recent Advances in Animal Nutrition in Australia 16, 123–134.

Dixon, RM, Playford, C, and Coates, DB (2011). Nutrition of beef breeder cows in the dry tropics. 1. Effects of nitrogen supplementation and weaning on breeder performance. Animal Production Science 51, 515–528.
Nutrition of beef breeder cows in the dry tropics. 1. Effects of nitrogen supplementation and weaning on breeder performance.Crossref | GoogleScholarGoogle Scholar |

Dixon, RM, Shotton, P, and Mayer, R (2020). Diets selected and growth of steers grazing buffel grass (Cenchus ciliaris cv Gayndah)–centro (Centrosema brasilianum cv Oolloo) pastures in a seasonally dry tropical environment. Animal Production Science 60, 1459–1468.
Diets selected and growth of steers grazing buffel grass (Cenchus ciliaris cv Gayndah)–centro (Centrosema brasilianum cv Oolloo) pastures in a seasonally dry tropical environment.Crossref | GoogleScholarGoogle Scholar |

Fianu FK (1982) The role of forbs and shrubs in the nitrogen intake of grazing livestock in the Accra plains. In ‘Forage protein in Ruminant animal production. Occasional Publication No. 6 – British society of animal production 1982’. (Eds DJ Thomson, DE Beever, RG Gunn) pp. 189–191.
| Crossref |

Graetz, RD, and Wilson, AD (1980). Comparison of the diets of sheep and cattle grazing a semi-arid chenopod shrubland. Australian Rangelands Journal 2, 67–75.
Comparison of the diets of sheep and cattle grazing a semi-arid chenopod shrubland.Crossref | GoogleScholarGoogle Scholar |

Hall, TJ (1981). The nitrogen and phosphorus concentrations of some pasture species in the Dichanthium–Eulalia grasslands of north-west Queensland. Australian Rangelands Journal 3, 67–73.
The nitrogen and phosphorus concentrations of some pasture species in the Dichanthium–Eulalia grasslands of north-west Queensland.Crossref | GoogleScholarGoogle Scholar |

Hall, TJ, and Lee, GR (1980). Response of Astrebla spp. grassland to heavy grazing by cattle and light grazing by sheep in north-west Queensland. Australian Rangelands Journal 2, 83–93.
Response of Astrebla spp. grassland to heavy grazing by cattle and light grazing by sheep in north-west Queensland.Crossref | GoogleScholarGoogle Scholar |

Hall, TJ, McIvor, , Jones, P, Smith, DR, and Mayer, DG (2016). Comparison of stocking methods for beef production in northern Australia: seasonal diet quality and composition. The Rangeland Journal 38, 553–567.
Comparison of stocking methods for beef production in northern Australia: seasonal diet quality and composition.Crossref | GoogleScholarGoogle Scholar |

Hennessy, DW, and Williamson, PJ (1990). Feed intake and liveweight of cattle on subtropical native pasture hays. 1. The effect of urea. Australian Journal of Agricultural Research 41, 1169–1177.
Feed intake and liveweight of cattle on subtropical native pasture hays. 1. The effect of urea.Crossref | GoogleScholarGoogle Scholar |

Hogan, JP (1996). Options for manipulation nutrition if feed supply is immutable. Australian Journal of Agricultural Research 47, 289–305.
Options for manipulation nutrition if feed supply is immutable.Crossref | GoogleScholarGoogle Scholar |

Hogan, JP, Kennedy, PM, McSweeney, CS, and Schlink, AC (1989). Quantitative studies of the digestion of tropical and temperate forages by sheep. Australian Journal of Experimental Agriculture 29, 333–337.
Quantitative studies of the digestion of tropical and temperate forages by sheep.Crossref | GoogleScholarGoogle Scholar |

Holm, AMcR, and Eliot, GJ (1980). Seasonal changes in the nutritive value of some native pasture species in north-western Australia. The Australian Rangeland Journal 2, 175–182.
Seasonal changes in the nutritive value of some native pasture species in north-western Australia.Crossref | GoogleScholarGoogle Scholar |

Holroyd, RG, Mason, GWJ, Loxton, ID, Knights, PT, and O’Rourke, PK (1988). Effects of weaning and supplementation on performance of Brahman cross cows and their progeny. Australian Journal of Experimental Agriculture 28, 11–20.
Effects of weaning and supplementation on performance of Brahman cross cows and their progeny.Crossref | GoogleScholarGoogle Scholar |

Innes, RR, and Mabey, GL (1964). Studies on browse plants in Ghana. III. Browse/grass ingestion ratios. (a) Determination of the free-choice Griffonia/grass ingestion ratio for West African Shorthorn cattle on the Accra plains using the ‘simulated shrub’ technique. Empire Journal of Experimental Agriculture 32, 180–192.

Kennedy, PM, Boniface, AN, Liang, ZJ, Muller, D, and Murray, RM (1992). Intake and digestion in swamp buffaloes and cattle. 2. The comparative response to urea supplements in animals fed tropical grasses. Journal of Agricultural Science, Cambridge 119, 243–254.
Intake and digestion in swamp buffaloes and cattle. 2. The comparative response to urea supplements in animals fed tropical grasses.Crossref | GoogleScholarGoogle Scholar |

Lorimer, MS (1978). Forage selection studies. 1. The botanical composition of forage selected by sheep grazing Astrebla spp. pasture in north-west Queensland. Tropical Grasslands 12, 97–108.

Lorimer, MS (1981). Forage selection studies. 2. Diet quality, liveweight change and wool production of sheep grazing Astrebla spp. pasture in north-west Queensland. Tropical Grasslands 15, 183–192.

McGowan M, McCosker K, Fordyce G, Smith D, O’Rourke P, Perkins N, Barnes T, Marquart L, Morton J, Newsome T, Menzies D, Burns B, Jephcott S (2014) Northern Australian beef fertility project: CashCow. Final Report B.NBP.0382. Meat and Livestock Australia, Sydney, NSW, Australia.

McLennan SR, Hendricksen RE, Beale IF, Winks L, Miller CP, Quirk MF (1988) The nutritive value of native pastures. In ‘Native Pastures in Queensland. The resources and their management’. (Eds WH Burrows, JC Scanlan, MT Rutherford) pp. 21–33. (Queensland Department of Primary Industries, Q187023: Brisbane, Qld, Australia)

McLennan SR, Dixon RM, Hendricksen R, Dodt R (1999) Nutrition of cattle in western Queensland. Report to the Western Queensland Regional Beef Research Committee, Department of Primary Industries, Qld Government.

McLennan, SR, Bolam, MJ, Kidd, JF, Chandra, KA, and Poppi, DP (2016). Responses to various protein and energy supplements by steers fed low-quality hay. 1. Comparison of response surfaces for young steers. Animal Production Science 57, 473–488.
Responses to various protein and energy supplements by steers fed low-quality hay. 1. Comparison of response surfaces for young steers.Crossref | GoogleScholarGoogle Scholar |

McMeniman, NP, O’Dempsey, N, Niven, DR, Jordan, D, and O’Brian, J (1982). The effect of cottonseed meal and urea supplementation on the reproductive performance of ewes in central and south west Queensland. Proceedings of the Australian Society of Animal Production 14, 447–450.

McMeniman, NP, Beale, IF, and Murphy, GM (1986a). Nutritional evaluation of south-west Queensland pastures. 1. The botanical and nutrient content of diets selected by sheep grazing Mitchell grass and mulga/grass associations. Australian Journal of Agricultural Research 37, 289–302.
Nutritional evaluation of south-west Queensland pastures. 1. The botanical and nutrient content of diets selected by sheep grazing Mitchell grass and mulga/grass associations.Crossref | GoogleScholarGoogle Scholar |

McMeniman, NP, Beale, IF, and Murphy, GM (1986b). Nutritional evaluation of south-west Queensland pastures. 2. The intake and digestion of organic matter and nitrogen by sheep grazing Mitchell grass and mulga/grass associations. Australian Journal of Agricultural Research 37, 303–314.
Nutritional evaluation of south-west Queensland pastures. 2. The intake and digestion of organic matter and nitrogen by sheep grazing Mitchell grass and mulga/grass associations.Crossref | GoogleScholarGoogle Scholar |

McMeniman, NP, Beale, IF, and Payne, G (1989). The nutrient status of sheep grazing on a dry Mitchell grass pasture association on central-western Queensland. Australian Rangeland Journal 11, 7–14.
The nutrient status of sheep grazing on a dry Mitchell grass pasture association on central-western Queensland.Crossref | GoogleScholarGoogle Scholar |

Milson J (2000) ‘Pasture plants of north west Queensland’, (Department of Primary Industries Queensland: Brisbane, Qld, Australia)

Minson DJ (1990) ‘Forage in ruminant nutrition’, (Academic Press: London, UK)

Newman, DMR (1969). The chemical composition, digestibility and intake of some native pasture species in central Australia during winter. Australian Journal of Experimental Agriculture and Animal Husbandry 9, 599–602.
The chemical composition, digestibility and intake of some native pasture species in central Australia during winter.Crossref | GoogleScholarGoogle Scholar |

NRBC (2016) ‘Nutrient requirements of beef cattle’, 8 revised edn. (The National Academies Press: Washington DC, USA)

Orr, DM (1975). A review of Astrebla (Mitchell grass) pastures in Australia. Tropical Grasslands 9, 21–36.

Orr, DM, and Phelps, DG (2013a). Impact of level of utilization by grazing on an Astrebla (Mitchell grass) grassland in north-western Queensland between 1984 and 2010. 1. Herbage mass and population dynamics of Astrebla spp. The Rangeland Journal 35, 1–15.
Impact of level of utilization by grazing on an Astrebla (Mitchell grass) grassland in north-western Queensland between 1984 and 2010. 1. Herbage mass and population dynamics of Astrebla spp.Crossref | GoogleScholarGoogle Scholar |

Orr, DM, and Phelps, DG (2013b). Impact of level of utilization by grazing on an Astrebla (Mitchell grass) grassland in north-western Queensland between 1984 and 2010. 2. Plant species richness and abundance. The Rangeland Journal 35, 1–15.
Impact of level of utilization by grazing on an Astrebla (Mitchell grass) grassland in north-western Queensland between 1984 and 2010. 2. Plant species richness and abundance.Crossref | GoogleScholarGoogle Scholar |

Orr, DM, Evenson, CJ, Jordan, DJ, Bowly, PS, Lehane, KJ, and Cowan, DC (1988). Sheep productivity in an Astrebla grassland of south-west Queensland. Australian Rangeland Journal 10, 39–47.
Sheep productivity in an Astrebla grassland of south-west Queensland.Crossref | GoogleScholarGoogle Scholar |

Pritchard, DA, Connelly, PT, Kelly, JG, and Hopkins, PS (1986). Diet selection and wool growth of high and low producing sheep at pasture in north-west Queensland. Proceedings of the Australian Society of Animal Production 16, 307–310.

Roe, R, and Allen, GH (1993). Studies on the Mitchell grass association in South-western Queensland. 3. Pasture and wool production under different rates of stocking and continuous or rotational grazing. The Rangelands Journal 15, 302–319.
Studies on the Mitchell grass association in South-western Queensland. 3. Pasture and wool production under different rates of stocking and continuous or rotational grazing.Crossref | GoogleScholarGoogle Scholar |

Sage, RF (2016). A portrait of the C4 photosynthetic family on the 50th anniversary of its discovery: species number, evolutionary lineages, and Hall of Fame. Journal of Experimental Botany 67, 4039–4056.
A portrait of the C4 photosynthetic family on the 50th anniversary of its discovery: species number, evolutionary lineages, and Hall of Fame.Crossref | GoogleScholarGoogle Scholar | 27053721PubMed |

Shenk, JS, and Westerhaus, MO (1991). Population definition, sample selection, and calibration procedures for near infrared reflectance spectroscopy. Crop Science 31, 469–474.
Population definition, sample selection, and calibration procedures for near infrared reflectance spectroscopy.Crossref | GoogleScholarGoogle Scholar |

Siebert, BD, Newman, DMR, and Nelson, DJ (1968). The chemical composition of some arid zone pasture species. Tropical Grasslands 2, 31–40.

Smith PC, Cheffins RC (1986) ‘Beef production in the Mitchell grass downs’, (Department of Primary Industries, Queensland Government: Qld, Australia)

Squires, VR, and Siebert, BD (1983). Botanical and chemical components of the diet and liveweight change in cattle on semi-desert rangeland in central Australia. Australian Rangeland Journal 1, 28–34.
Botanical and chemical components of the diet and liveweight change in cattle on semi-desert rangeland in central Australia.Crossref | GoogleScholarGoogle Scholar |

Stephenson, RGA, and Hopkins, PS (1978). Urea supplementation of ewes in the tropics. Proceedings of the Australian Society of Animal Production 12, 178.

Stephenson, RGA, Edwards, JC, and Hopkins, PS (1981). The use of urea to improve milk yields and lamb survival of Merinos in a dry tropical environment. Australian Journal of Agricultural Research 32, 497–509.
The use of urea to improve milk yields and lamb survival of Merinos in a dry tropical environment.Crossref | GoogleScholarGoogle Scholar |

Stephenson, RGA, Weston, RH, Margan, D E, and Hogan, JP (1983). Intake and digestion of mature Flinders grass (Iseilema spp.) by sheep and their response to the addition of urea and minerals. Australian Journal of Agricultural Research 34, 549–556.
Intake and digestion of mature Flinders grass (Iseilema spp.) by sheep and their response to the addition of urea and minerals.Crossref | GoogleScholarGoogle Scholar |

Tothill JC, Hargreaves JNC, Jones RM, McDonald CK (1992) ‘BOTANAL – a comprehensive sampling and computing procedure for estimating pasture yield and composition. 1. Field sampling.’ Technical Memorandum No. 78. (Division of Tropical Crops and Pastures, CSIRO: Australia)

Weston EJ (1988) Native pasture communities. In ‘Native Pastures in Queensland. The resources and their management’. QI87023. (Eds WH Burrows, JC Scanlan, MT Rutherford) pp. 21–33. (Queensland Department of Primary Industries: Brisbane, Qld, Australia)

Weston, EJ, and Moir, KW (1969). Grazing preferences of sheep and nutritive value of plant components in a Mitchell grass association in north-western Queensland. Queensland Journal of Agricultural and Animal Sciences 26, 639–650.

Wilson, AD (1976). Comparison of sheep and cattle grazing on a semi-arid grassland. Australian Journal of Agricultural Research 27, 155–162.
Comparison of sheep and cattle grazing on a semi-arid grassland.Crossref | GoogleScholarGoogle Scholar |

Winks L (1984) ‘Cattle growth in the dry tropics of Australia.’ Review number 45. (Australian Meat Research Committee: Sydney, NSW, Australia)

Winks, L, Laing, AR, O’Rourke, PK, and Wright, GS (1979). Factors affecting response top urea-molasses supplements by yearling cattle in tropical Queensland. Australian Journal of Experimental Agriculture and Animal Husbandry 19, 522–529.
Factors affecting response top urea-molasses supplements by yearling cattle in tropical Queensland.Crossref | GoogleScholarGoogle Scholar |

Winter, WH, Winks, L, and Seebeck, RM (1991). Sustaining productive pastures in the tropics. 10. Forage and feeding systems for cattle. Tropical Grasslands 25, 145–152.