Her 4-year-old Sara was most intrigued with the cards and enjoyed learning about the animals, she said.
"I think they are brilliant. She is quite into animals at the moment, so it's quite appropriate for her."
The sounds the cards made when put through the reader were "really authentic," she said, and the album contained a lot of information.
It is only early days as the promotion runs until the middle of next month but the grandparents had already been called in to help increase the collection, she said.
"We have asked the grandparents but my sister-in-law got in first, so they will sort of have to remember to divide them between us."
Countdown would pledge $1 from every album sold to the SPCA and Mrs Hudson said it felt like she had contributed to a worthwhile cause.
Bureta Park Countdown store manager James Liddell said the cards were well received by customers.
There has certainly been a lot of interest, he said, and he was collecting them for his grandson.
"I think they are a good learning experience and quite interactive and engaging."
Countdown marketing general manager Bridget Lamont said proceeds from the album sales would go toward Shelter Buddy, an animal management system for all the regional SPCA centres to share information.
Response from around the country, including Tauranga, had been positive, she said. "We've had a lot of feedback about the hours of fun the cards are providing."