Investigating the causes of calf losses in extensive pastoral systems - Calf watch

Summary

Investigating calf loss in northern Australia has been difficult using traditional methods. This is because calving females and calf carcases are difficult to find in large paddocks, and close observation during calving alters behaviour. The ability to remotely monitor calving would greatly improve research into calf loss. The CalfWatch project developed a system to remotely monitor calving under extensive conditions in northern Australia and used it to investigate calf loss over two calving seasons at Manbulloo station near Katherine (NT).

Northern Territory Department of Industry, Tourism and Trade (NT DITT) staff worked with University of Florida researchers to modify existing birth sensors to increase the range and enable use in locations where mobile phone coverage was limited. Tracking of cows using GPS was necessary to find calving cows after an alert was received and DITT researchers worked with Smart Paddock Pty Ltd to develop a suitable tracking system for extensive systems.

The CalfWatch system was effective for monitoring calving when all components worked properly, although the performance of the birth sensors and GPS collars was variable over the two calving seasons. The project gained insights into the causes of calf loss in extensive northern herds and has been another step forward in addressing the problem of calf loss in northern Australia.

Objectives

The objectives of this project were to:
1. Review the remote calf loss monitoring systems and develop ways to modify them so they are suitable for use in northern Australian conditions.
2. Develop and test systems that remotely record calving time and location and remotely monitor calves so that deaths can be detected and carcases located in extensive conditions.
3. Use the systems developed in objectives one and two to investigate the causes of calf loss on a research site near Katherine, NT.

Key findings

The technology and systems were evaluated and successfully adapted to extensive conditions where mobile phone reception is limited. The birth sensors had variable performance, but when they worked correctly the system worked well and cows could be found for observation at calving.

Benefits to industry

The project increased the understanding of the causes of calf loss in extensive northern herds, although there was still a significant proportion of losses due to unknown causes where the equipment failed or loss occurred after calving observations were made. Observations made possible through use of the CalfWatch system indicate that bottle teats are likely to be a bigger problem in northern herds than previously thought.

MLA action

Further investment is being made into the reducing calf losses in northern Australia, including through reducing exposure.

Future research

A recommendation of this project is to develop collars that enable GPS tracking of cows in real time and can send calving alerts from accelerometer data. Further research should also continue to focus on the cause of calf loss, as a high proportion could not be identified.