Mice can apparently cough,
according to a new study which suggests the rodents can be used in research to fight coughing in humans.
It was a mystery as to whether mice can cough, since any such sounds would probably be barely audible at best.
Scientists at Guangzhou Medical College in China exposed 40 mice to fine mists of capsaicin, the molecule that makes chili peppers spicy.
The mice were each placed in a machine known as a plethysmograph, a device that measures changes in body volume to detect when air moved in and out of the mice.
The researchers also listened to mouse sounds with mini-microphones and watched the mice to monitor their body movements, LiveScience reported.
The rodents made a variety of sounds while sniffing, tapping their teeth, scratching their noses and twitching their heads.
Among these sounds, the scientists identified explosive noises that coincided with the abrupt head-tossing, abdominal jerking and opened mouths one would expect with coughs.
When given cough suppressants such as codeine, mouse coughing dropped dramatically. Capsaicin given before the experiment also helped suppress coughing during the experiments, likely by desensitising the mice's nerves.
These findings suggest mice could be used in experiments looking for cough syrups and other medicines to fight coughing.
Currently, guinea pigs are used for such tests, but they can be relatively expensive compared with smaller mice.
Recently, scientists have found that mice can sing ultrasonic melodies and rats laugh when tickled. This research adds to behaviour people might not think rodents are capable of, said behavioural neurobiologist Erich Jarvis at Duke University Medical Center, who did not take part in this coughing research.
"It would be interesting to see if it's possible to get mice to voluntarily cough, and if so, what are the neural mechanisms in the brain for that," Jarvis told the website.
"If they can voluntarily cough, maybe the neural circuits for such coughing could be the precursors for their vocal communication circuits," he added.
The study was published in the journal PLOS ONE.
