Mars Inc. business units are donating $475,000 to organizations providing emergency relief in Haiti.  The donations include: $345,000 to the Red Cross, $120,000 to the Search Dog Foundation and $10,000 to the American Veterinary Foundation. In addition, Mars is donating pet food and supplies to the Humane Society Foundation as part of the Animal Relief Coalition for Haiti.  McLean-based Mars is a family-owned company whose products include chocolate candy, chewing gum and pet foods.