22 April 2014
Genetic researchers at the University of the Sunshine Coast have determined that female prawns are most likely serial monogamists.
Five USC academics and a biologist from North Queensland prawn farming operation, Seafarm, applied the same testing used in human crime cases to assess whether female prawns contained traces of DNA from more than one male after spawning events.
Their finding that each female paired up with just one male partner at a time could prove invaluable to the aquaculture industry in managing the genetic diversity of their stock and production.
A report on the research has been published by the scientific website, ScienceDirect.
USC’s Associate Professor of Genetics Wayne Knibb said the research involved an original use of microsatellite genotype analysis to test female prawns for evidence of their partners.
“This is the first time we’ve used DNA forensics to understand the private life of prawns and the first time it’s been used in the whole order of decapod crustaceans, which includes crabs and lobsters,” he said, adding that the study did not assess the faithfulness of male prawns.
“It turns out that female prawns are monogamous for a time and mate with only one male during each spawning event. However, this ‘piety’ lasts only for one month, since every month the female will grow a new skin. And when she does, she’ll find a new male.”
Dr Knibb said the research had been supported by the Australian Seafood Cooperative Research Centre, The Australian Fisheries Research and Development Corporation, the Australian Prawn Farmers Association and Seafarm at Cardwell. “One purpose of this study was for us, as geneticists, to better understand whether the traits of the prawn are due to genetics or the environment,” he said. “Knowing how many partners prawns have helps us to calculate the genetic contributions.
“However, as geneticists, we’d actually prefer the mums to be polygamous so as to promote greater genetic diversity and to more accurately calculate the genetic effects. A little less piety would be helpful, perhaps. After this study, we’ll probably recommend that prawn farmers use artificial insemination and take away mum’s choice to have just one mate.
“Not only will this permit more accurate calculations, but this way we can pair the prawns best for production and avoid mating of relatives. “With multiple partners, we will be able to more accurately select the best animals for broodstock for the next generation.”
— Terry Walsh