Pet toy sales are showing some bite.

Those chew toys for Fido and related goods have become the hottest sector in the toy business — posting annual growth rates in the mid-single digits while sales of children’s toys are shrinking, industry statistics show.

In 2017, pet toy sales are expected to exceed $1 billion for the first time.

The fast-paced growth has convinced some nontraditional toy sellers, like Home Depot, T.J.Maxx and even Tractor Supply Co., to start stocking pet toys in recent years.

“Toys have held steady at about $21 billion on average for the past decade, but the pet industry is growing like crazy,” said Jim Silver, president of TTPM, a toy-review Web site, which began reviewing pet products a couple of years ago, because pet parents wanted to know they are buying safe and quality made doodads for their pets.

Experts peg the growth of pet toy sales to millennials, who are putting off marriage and having kids — but welcoming a pet.

In fact, a study this past summer showed many 20-to-36-year-olds consider their furry companions as starter children.

Pet ownership has grown by 5 percent since 2014 to 68 percent of US households, according to American Pet Products Association.

“[Millennials] are the largest group of pet parents today and are buying everything from automatic feeders to GPS products to keep track of their pets while they are at work,” Andy Krinner, TTPM’s pet content director, said Tuesday at a Manhattan pet trade show.

One pet toy supplier, Petmate, has used the rapid sales growth to recruit 10 former toy industry veterans to the pet toy sector, according to the company’s Chris Wilson.