The agency defeated Universal McCann to pick up the centralised business. It adds £4 million to OMD's existing Nestle petfoods billings. The appointment comes four months after DDB Worldwide was handed the creative brief.
Nestle Purina produces brands such as Friskies dog and cat food and the Felix petfood range. Felix made its TV sponsorship debut earlier this year by tying up with ITV1's Sunday evening show You've Been Framed.
The Nestle Purina division was formed last December when Nestle acquired the US petfood giant Ralston Purina for £7.4 billion.
Nestle aims to challenge Mars as the world leader in petfood. The Swiss company estimates that the global petfood market is worth $38 billion.
The UK petfood market was worth £1.49 billion in 2001, a rise of 4.2 per cent on 2000, according to the Leatherhead Food Research Association.