Weighing a couple of tonnes and with jaws that can kill, the hippopotamus is about to open up and say aaah for science.
UQ reproductive biologist Dr Steve Johnston will use paper cups and quick reflexes to scoop saliva from the mouths of Nile hippopotamuses at Mexico’s biggest private zoo, Africam Safari.
Dr Johnston said the work was part of his three-month study tour at the zoo starting in October to learn more about the reproductive cycles of the hippo and to collect and freeze sperm from the white rhinoceros and giant ant-eater.
He said testing hormones in the hippo’s saliva would tell him more about their reproductive lives.
His aim is to come up with a non-invasive test that would allow zoos to determine the reproductive condition of their hippos, such as whether they were pregnant, sexually mature or infertile.
One of the vets at the zoo has trained the hippos to walk into an enclosure and open their mouths on queue.
“They’re a big animal and difficult to work with but one of my colleagues in Mexico, Dr Gerardo Marinez, is quite brilliant at animal conditioning,” Dr Johnston said.
“He has already trained the hippos to walk into a chute and drop their bottom jaw to saliva up and we simply collect it with a paper cup.
“The saliva just pores out of salivary glands like a drinking fountain!”
The zoo has about 20 hippos that make up one of the few breeding herds in captivity.
“While hippos breed pretty well in captivity, there is almost no information on the reproductive physiology of the male and female. We aim to change that.”
While in Mexico Dr Johnston will also collect semen from other exotic animals to help with a study on sperm DNA damage in collaboration with the University of Madrid.
Dr Johnston and Professor Jaime Gosalvez have been developing a way to measure the extent of sperm DNA damage in a range of species including echidnas and koalas which could accurately predict fertility.
While based at Africam, Dr Johnston will collect and freeze sperm from white rhinos and from the giant ant-eater, which has not been done before, and then send the frozen semen to Spain for DNA analysis.
Dr Johnston is a Senior Lecturer based at Pinjarra Hills with UQ’s School of Animal Studies under the Faculty of Natural Resources and Veterinary Science.
MEDIA: Dr Johnston (0408 280 963) or Miguel Holland at UQ Communications (07 3365 2619, m.holland@uq.edu.au)
