Sometimes an obsession with pets can pay off. This week online dog community Dogster announced plans to sell advertising for pet humor empire I Can Haz Cheezburger.

When did Dogster become an ad network? Apparently, over the past five years it spent cultivating ad relationships instead of banging on doors looking for VC money.

The result? Premium ad sales for Dogster, Catster and Snuzzy are up 20% this year. According to TechCrunch:

“While hot sites like Digg and Facebook outsourced ads to big
players like Microsoft and smaller sites outsourced them to Google,
Dogster has invested five years in building direct relationships with
big pet food, supply and other consumer packaged good brands. “We
figured each $50,000 ad deal was like getting another angel investor,”
says Ted Rheingold, Dogster CEO.”

TechCrunch’s Michael Arrington may be an investor in Dogster, but their model is worth noting. Dogster has spent a good chunk of time working on advertiser relationships that integrate ads into the company’s content. And now, it can outsource its pet expertise to other similarly themed companies.

Like I Can Haz Cheezburger. The popular network of humor sites is on track to pass 1 billion page views this week. And while ICanHazCheezburger may not be a directly pet related site, the content overlap is enough to make it viable for the companies to work together.

I Can Has Cheezburger’s Ben Huh tells TechFlash:

“We feel that with vertical-specific networks, we can leverage their
endemic sales force while not having to build and support our own —
given that our sales people would have to be generalists due to our
size and reach.”