Revisiting tropical pasture intake: what has changed in 50 years?

E. Charmley; D. Thomas; G. J. Bishop-Hurley

doi:10.1071/AN23045

ANIMAL SCIENCE REFLECTIONS (Open Access)

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Revisiting tropical pasture intake: what has changed in 50 years?

E. Charmley

^A ^* , D. Thomas

^B and G. J. Bishop-Hurley ^C

+ Author Affiliations

- Author Affiliations

^A CSIRO Agriculture and Food, Private Mail Bag PO, Aitkenvale, Townsville, Qld 4814, Australia.

^B CSIRO Agriculture and Food, Centre for Environment and Life Sciences, Private Bag 5, Wembley, WA 6913, Australia.

^C CSIRO Agriculture and Food, 306 Carmody Road, St Lucia, Qld 4067, Australia.

^* Correspondence to: ed.charmley@csiro.au

Handling Editor: David Masters

Animal Production Science 63(18) 1851-1865 https://doi.org/10.1071/AN23045

Submitted: 31 January 2023 Accepted: 29 March 2023 Published: 21 April 2023

Abstract

The measurement and prediction of pasture intake in extensive grazing systems, typical of northern Australia, remain elusive after 50 years of research. The aim of this paper is to review research conducted over the past 50 years, highlight advances in understanding, discuss remaining challenges and consider future developments with digital technologies. While the fundamental components of voluntary intake are well understood, their measurement is difficult, particularly in extensive grazing systems, which has limited the development of predictive models that adequately address the interplay of factors influencing intake from the bite to the landscape scale. Ongoing research by the authors is used as an example to highlight the potential application of digital technologies to overcome limitations in measurement and prediction. Digital technologies offer the opportunity for monitoring factors that control voluntary pasture intake at scale and under commercial conditions. However, our ability to ground-truth novel indices of intake remains limited without ongoing development of physical methods. This will limit the accuracy and precision of predictive models incorporating digital technologies that can be applied to the extensive grazing conditions of northern Australia. The advent of precision livestock management for extensive cattle production is essential if the industry is to remain viable in the future where production is transparent, ethically sound and environmentally defensible as well as profitable.

Keywords: Beef cattle, grazing behaviour, information technology, intake, modelling, pasture, review, tropical.

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