“Yes they do talk back. They’re talking to us by means of various physiological change. ”
Talking to mussels won’t help you breed better-quality products. But listening to them might.
Cawthron shellfish physiologist Norman Ragg has devised a number of innovative techniques that allow him to communicate with mussels as part of the Institute’s selective breeding programme.
His way of talking to shellfish involves electrodes and heart monitors.
As Dr Ragg will demonstrate at the New Zealand Aquaculture Conference, by measuring an animal’s response to changes in temperate, stress and food environment he can theoretically identify animals with desirable traits that could lead to products with a longer shelf life, a higher tolerance for processing or more efficient growth.
“If you can envisage a mussel sitting in a psychiatrist chair we ask them two types of questions,” Dr Ragg said.
“The first is ‘how do you feel?’ – a question asked of an unknown situation when it could be in pristine condition or under stress – we monitor the feeding, metabolism and heart activity to get the answer.
“Then the other question is ‘how does this make you feel?’ Which sounds the same but is fundamentally different because you ask the question, then you apply the stress.
“You know something about the animal beforehand from the baseline information then you change the situation – very often it’s changing it for the worse.
“The objective is to determine how well the animal tolerates the less than optimal conditions.”
If you were able to visualise Dr Ragg consulting with his mussel patient – now visualise the mussel politely answering his questions from that comfortable psychiatrist’s chair.
“Yes they do talk back. They’re talking to us by means of various physiological changes,” Dr Ragg said.
“So if you ask ‘how does this make you feel?’ – it’s pretty hard to tell what’s going on inside a mussel, but if you’ve got access to information like its heart rate or oxygen consumption, it’s instantaneous feedback and that’s as effective as language.”
And as he immerses himself deeper in the project, Dr Ragg is finding great insight from heart rates.
“One of the key parameters we’re finding really useful, that gives us data and is really reliable because it works every time, is to monitor heart activity,” he said.
“I look at temperature sensitivity.
“If you have two shells that can close tightly, you can isolate and protect yourself from almost anything, except temperature.
“So when on-growing and during processing the creature’s ability to survive temperature stress is absolutely crucial. You can’t avoid it, you can’t get around it.
“Initial trials show genetics plays a big part.
“There are some lines that are just more tolerant. Our aim is to efficiently identify and breed for a range of key characteristics, effectively providing growers with access to designer mussels suited to a wide range of conditions and requirements.”