The pet industry is expected to generate $51.6 billion this year, an increase of 1.3% from 2008, according to US industry research firm IBISWorld .

The firm predicted petfood production, which makes up 30% of the pet industry, to generate $15.2 billion this year and grow steadily in the next five years.

Over half of all pet owners have shown concern in what their pets are eating, according to IBISWorld, causing a shift in demand for premium, natural and organic petfood.

"Americans consider their pets as members of the family, making businesses that cater to our four-legged friends a stable, growing market," said George Van Horn, senior analyst at IBISWorld.

The pet industry broken down by research firm IBISWorld.