While it might lack the colour or chaos of a typical Melbourne Zoo enclosure, a frozen blood bank tucked away in Royal Park's veterinary precinct is helping scientists understand more about zoo animals.
There are more than 18,000 samples kept in Melbourne Zoo's blood serum bank, with the oldest specimens dating back as early as the 1990s.
"The serum bank is really useful to us," said Melbourne Zoo head veterinarian Michael Lynch.
"It's a collection of blood from animals we've had here at the zoo and wild animals which we use to help in their health management.
"We have such a wide variety of species here that often it's hard to know what's normal, and what's not.
"If we are looking at a particular thing in blood, we can go back and compare an animal to other animals like it."
Dr Lynch said the zoo's serum bank was the oldest in Australia and blood banks were becoming an increasingly important part of animal health care at zoos both across the country and globally.
Blood samples are frozen at subarctic temperatures
The serum samples are kept at an average temperature of an icy minus 79 degrees Celsius.
Zookeepers handling them need to wear specially designed gloves.
"You've got to be careful," senior zookeeper Jody Van Gulik said.
"Because the temperature is so low, if you don't wear any protective gear, like the ultra-cold gloves that we have to use, you'll actually get stuck to the freezer."
Mr Van Gulik is in charge of keeping track of all the samples in the blood bank – he said all kinds of animals, big and small, native and exotic, are represented in the serum bank.
Individual samples can last for decades
Scientists at the Melbourne Zoo store blood serum, a clear liquid derived from blood, because it is useful for a variety of different tests and also keeps for a really long time when frozen.
"When you collect blood from an animal and let it clot, it separates into red blood cells and the leftover is serum," Dr Lynch said.
"That's what we use and you can store that long-term."
Scientists use a centrifuge, a machine that rapidly rotates, to split a blood sample and separate the serum.
Mr Van Gulik said vets will often take a little extra blood from zoo animals to store in the serum bank, to minimise the number of times they need to draw it.
"We are not dealing with domestic animals so we can't take a blood sample from the animals every time you need to do so," he said.
Collection helps inform research
The serum bank has proven to be a great tool for researchers, too.
Recently, samples from the serum bank were used to help develop a new marsupial-specific blood test for toxoplasmosis, something Dr Lynch described as a "particularly nasty disease".
"A researcher is using a whole variety of serums from species we've had here at the zoo, to develop a diagnostic test for that," he said.
"It's important for us in our management of native wildlife."
Mr Van Gulik said it was great to know the collection could benefit generations of zoo animals to come.
And while the serum bank is helping to develop tools for the future, Dr Lynch said it was also useful for looking back into the past, to monitor things like historic diseases that scientists might not know about.
"We might only find something now, but if we don't know if they've had it for a long time, we can also use the serum bank to see what has happened in the past," he said.
