University of Adelaide research into parasites of cuttlefish, squid and octopus has uncovered details of the parasites’ astonishing life cycles, and shown how they may help in investigating populations of their hosts.
Researcher Dr Sarah Catalano has described 10 new parasite species− dicyemid mesozoans −, which live in the kidneys of cephalopods (cuttlefish, squid and octopus). They are the very first dicyemid species to be described from Australian waters.
“Although dicyemid parasites have been studied by other groups, nothing has been known about dicyemid fauna and infection patterns from Australian waters,” says Dr Catalano, who this month will graduate with her PhD from the University’s School of Earth and Environmental Sciences. She will continue her work at the South Australian Museum.
The dicyemid parasites are tiny organisms, simple in appearance and made up of only 8-40 cells without any obvious tissue structure – but they do have surprisingly complex life cycles. They exist in two forms: adults are long and slender whereas embryos can be a clone of the adult only smaller, or have a distinctive circular form. They also have two modes of reproduction – sexual and asexual.
“Surprisingly, we found that the left and right kidneys of a single host individual were infected independently of each other, with one kidney infected by asexual forms and the other by sexual forms, suggesting this mechanism is parasite-controlled not host-mediated,” says Dr Catalano. This finding has been published in the journal Folia Parasitologica.
“To make their life cycle that much more complex, these parasites are also highly host-species specific. To infect a new host, the circular embryo form of the parasite is released with the host’s urine out into the sea. It then has to find a new squid or cuttlefish or octopus individual that is of the right species within a limited time-frame before it perishes, while also battling environmental conditions such as strong water currents and varying salinity.
“Somehow this tiny organism – just a few cells in size – manages this complex and highly specific reinfection and the astonishing life cycle beings again.”
This high degree of specificity means the parasites have potential use as “biological tags” to help assess population structures of cephalopods, including the iconic giant Australian cuttlefish.
“We looked at the dicyemids in two species of cuttlefish, the giant Australian cuttlefish and the nova cuttlefish, from various localities in South Australian waters,” Dr Catalano says. “We found different dicyemid species infected each cuttlefish species at different localities, suggesting there are unique populations of each host species in South Australian waters.
“As such, this offers support for the use of dicyemid parasites as biological tags and we hope to be able to use these parasites to tell us more about cephalopod population structure to assist in management plans.”
Dr Sarah Catalano
School of Earth and Environmental Sciences
The University of Adelaide
Phone: +61 8 8313 5513
Mobile: +61 (0) 437 574 880
Media and Communications Officer
The University of Adelaide
Phone: +61 8 8313 6341
Mobile: +61 410 689 084
Robyn Mills | newswise
Managing an endangered river across the US-Mexico border
18.07.2016 | International Institute for Applied Systems Analysis (IIASA)
The European pet trade is jeopardising the survival of rare reptile species
13.07.2016 | Helmholtz-Zentrum für Umweltforschung - UFZ
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
15.07.2016 | Event News
15.07.2016 | Event News
11.07.2016 | Event News
26.07.2016 | Information Technology
26.07.2016 | Health and Medicine
26.07.2016 | Physics and Astronomy