Unlike cat and dogs breeders, however, casual observers, could be inclined to shriek at her animals, dismiss them as vermin or pests, or compare them to politicians who have deserted their parties.

The Blazing Tails Rodentry owner was well aware that mice and rats had a public image problem, but said perceptions were slowly changing as people discovered their suitability as pets.

Her mission, as a breeder of up to 10 litters of mice and two to three litters of rats per year, was to encourage the purchase and continuation of healthy lines of the species.

"The problem with mice and rats in the community is there's a prevalence of respiratory infection, and there can be temperament issues with biting," she said.

"The point of being a breeder is to create healthier animals to go out and be pets. It's the same principle as being a cat or dog breeder, just more pocket-sized."

Understanding of fancy mice - those selectively bred for exhibition - has grown in recent years, but ownership numbers remain low.

An Animal Medicines Australia report from 2016 found that, of the 3 per cent of Australian households with small mammals as pets, 13 per cent owned mice or rats.

About 15 per cent of members of Generation Y surveyed were keen to acquire a small mammal in the future, while there was a 10.8 per cent increase in the population of pets outside dogs, cats, fish and birds between 2013 and 2016.

Ms Richardson did not originally consider breeding as a profession. Instead, she wanted to buy some mice after fond memories of the pets when she was younger.

"So I got a couple of mice off Gumtree and wondered if there was a club for rats and mice owners around," she said.

Her search led to her to join the Australian Rodent Fanciers Society of NSW, which provided information about breeding and the opportunity to take part in shows.

She learned to specialise in Siamese mice, a breed with similar colours and markings to the cats of the same name.

Since then, she has spent time equivalent to that of a part-time job each week at her Amaroo home, raising and caring for her rodents.

"I have to clean [the house] quite frequently and pay attention to them, because rats thrive on companionship so you need to spend time with them," she said.

"There's definitely a lot of surprise in the community when you tell people you're a breeder, and there's even more surprise when you tell them you go to shows to show your animal."

Earlier this month, Ms Richardson was awarded the "Grand Champion Rat" and "Reserve Champion Mouse" prizes at the Hawkesbury Show in NSW.

The show categories judged the animals on their markings, coats, temperament, conformation and overall appearance.

Another Canberra region mousery, Fuzzle Puff, came home with two first prizes at the Royal Easter Show in Sydney.

Ms Richardson said those interested in buying a pet mouse or rat should look out for signs of health in the animals.

She hoped more breeders would pop up in the region to encourage the proliferation of healthier rodents.

"You need to look for a healthy animal, one that's quite robust, glossy, bright eyes, clear nose, no congestion," she said.

"Breeders tend to offer you more of a guarantee of good health, and hopefully people will continue to look beyond mice and rats as vermin and start to see their potential as a pet now."