Northern Australia's calf loss data

This was the message Dr Kieran McCosker, beef production scientist, Katherine, Northern Territory, was at the Calf Alive Symposium in Capella last week to deliver. 

Dr McCosker was first to speak at the two-day symposium which covered everything from why producers are losing calves, to how to raise a healthy calf. 

The data Dr McCosker was referencing came from the Cash Cow project, which included 72 properties and 78,000 head monitored over four years, with 150 mobs between them and about 800 females per mob. 

The lowest level of calf loss recorded in the northern forest region was 8pc, while the highest was 32pc. 

He said the middle – about 15pc – was typical foetal and calf loss rates for the region, however 25pc of the mobs involved had a higher than 18pc calf loss. 

The calf loss rates were lesser in second lactation females – females which have successfully reared a calf beforehand. 

“Previously 12% calf loss was thought to be attainable, but for the northern forest we’re saying it would be challenging to achieve that,” Dr McCosker said. 

In the research paper written by Dr McCosker, Geoffry Fordyce, Michael McGowan, and Brian Burns, Reproductive Wastage in Extensively-Managed Beef Cattle, the authors wrote that loss associated with reproductive disease, primarily BVDV and Campylobacter, was confirmed in northern mobs. 

They stated that a high proportion of losses occur within a week of birth, and while “specific causes of the majority of loss remain unconfirmed, recent research indicates that the primary causes are not infectious diseases, but are nutritionally related”. 

“Other than infectious diseases, predation and dehorning, calf death is likely to be the outcome of either the cow not providing enough milk, or the calf unable to suckle effectively (low vigour),” the report states.

Also noted was that while predation was a major cause of calf loss in the north, addressing the issue of wild dogs can have a desirable effect, with the flow-on effect of baiting leading to the dogs targeting non-preferred species – like calves.