It is one of the lesser known by-products of Australia's cattle industry, but its value is on the rise and has more than doubled since 2019.
Foetal calf blood, which is mostly used in medical research and pharmaceutical industries, has this month reached a record price of $615 a litre, ex-abattoir.
Mecardo analyst Adrian Ladaniwskyj said supply of the commodity was tight and the record price was an indicator of Australia's cattle herd rebuilding after years of drought.
"The ongoing, strong foetal calf blood market indicates that cattle producers are holding onto their females," he said.
"The amount of cows getting sent to abattoirs in Australia has reduced, and as a result of less cows getting slaughtered there's less calf serum getting produced, so the price goes up."
Cattle producers do not gain financially from the rising value of foetal bovine serum (FBS), but abattoirs do.
Essentially it is a lucrative surprise for abattoirs when a foetus shows up in the processing.
Weekly national slaughter data from Meat and Livestock Australia (MLA) shows that in May the ratio of female cattle getting slaughtered fell to just 36 per cent, compared to 45 per cent the same time last year and 52 per cent in May 2020.
Critical commodity for research community
Principal virologist at the Berrimah Veterinary Laboratory in Darwin, Dr Richard Weir, works with foetal bovine serum almost on a daily basis.
"It can be used in universities, vaccine manufacturers need it, and here in Darwin we use FBS for a range of cell cultures to isolate viruses for our diagnostic or research purposes," he said.
"To carry out [biosecurity] surveillance here in Darwin, which is important to the whole country, we need to grow cell cultures.
Dr Weir said in recent years labs had been paying $800-$1,200 a litre for FBS.
"This news [of record ex-abattoir prices] hasn't filtered through to us, but we aren't looking to buy a batch at the moment," he said.
"We bought a 100-litre batch about five years ago and we're roughly half way through it. So in probably the next 12 or 24 months we'll be looking to buy a new batch."
Cash injection for struggling abattoirs
Adrian Ladaniwskyj said Australian FBS sold for a premium because of the cattle industry's disease-free status.
He said with abattoirs struggling with high cattle prices and rising input costs, the sale of FBS would be helping their bottom line.
"There's a positive story here because not only is it used for a noble cause — where what could have been a waste-product is used in medical research to better people's lives — at the same time it's providing a bit of extra cash flow for processors [abattoirs] who are doing it quite tough at the moment."
