The secret sex lives of prawns are being revealed in a study that is trying to understand why the crustaceans do not breed well in captivity.

The giant black tiger prawn was first described in the 18th century and is one of the most popular high-quality species, with distinctive stripes that turn red when cooked.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 3 minutes 5 seconds 3 m 5 s Tianyi Feng says studying prawn sperm could help solve fertility problems in captivity Download 5.7 MB

But the mystery of how the species produces sperm is one that has never been solved.

University of Queensland PhD student Tianyi Feng said the question was critical for Australia's aquaculture industry, because the popular crustacean did not breed well in captivity.

"This prawn has been domesticated for almost five decades, but the view of the progress is very slow," he said.

"Most of the research thinks the major problem is the females, which have some difficulty in producing the mature eggs.

"But very few researchers are studying the male part ... we think there might be something wrong or maybe it's okay, but we need to figure out how to assess the male fertility, the quality of the sperm and how they get sexually mature."

Mr Feng has used electron microscopes to create detailed three-dimensional models of the prawn sperm cells to illustrate their composition.

Prawn sperm 'very different' to mammal sperm

He said crustacean sperm were very different to mammal sperm.

Prawn sperm do not have a tail like mammal sperm, and how they make their way to the egg is a mystery. ( Supplied: University of Queensland )

"Sperm have long swimming tails in mammals, but prawn sperm have no tails — they don't move at all and look more like thumb tacks, and it's an interesting mystery as to how the sperm gets into the egg," he said.

"Even if they are alive they don't move, so it's quite challenging.

"That's why we're going to try another technique like assessing the DNA damage of the sperm, and also for this paper we used the technique to see detail of the outer structure of this sperm.

"If we can use this to compare the normal sperm or the deformed or diseased sperm, we can figure out what's wrong in the detail rather than [just] seeing the motility of the sperm."

Wild-caught brood stock poses challenges

Mr Feng said the nation's billion-dollar aquaculture industry relied on wild-caught brood stock because prawns did not sexually mature well in farms.

In Asia, the practice has led to the introduction of devastating wild prawn diseases, which have the potential to wipe out the industry.

In Australia, strict quarantine vigilance has prevented major incursions, but the wild stock does still introduce minor disease that can be challenging to individual farms.

Mr Feng said his research could lead to better breeding efficiency with stock grown in bio-secure conditions, improved selective breeding, and even artificial insemination.

"If we don't improve this the industry will collapse sooner or later, because if you keep relying on the wild stock of this animal for each season's breeding, you will bring a lot of pathogens or viruses to the industry and there will be a catastrophic impact for the whole farming system," he said.

"Although the seafood industry is a multi-billion dollar industry internationally, there's a lot we still don't understand about the basic biology of valuable prawns such as these.

"If we knew more we could probably improve the efficiency of prawn breeding in aquaculture."

The research is published in the Journal of Morphology.