Mustang Marketing in Thousand Oaks plans to acquire ZestNet Inc., a traditional and digital marketing firm based in Ventura. The move will bring Mustang’s employee headcount to 16 and will extend its public relations and marketing services to west Ventura County and Santa Barbara. Mustang will keep both office locations open, the firm said in a statement, and ZestNet founder Ric Ruffinelli will stay on as an executive at the firm. “(Mustang Chief Executive Scott Harris) and I have been exploring opportunities to continue Mustang’s expansion of services, and this acquisition allows us to do so, while bringing together two talented teams,” Mustang President Dianne McKay said in a statement. The firm is looking to further build out its business on both a local and national level, McKay added. The acquisition is set to close April 1.