DULUTH, MN (KDAL) - The Northland Spay-Neuter Clinic at 2002 West Superior Street is holding an open house on Wednesday.  The open house celebrates the accomplishment of their goal of performing 20 thousand spay-neuter surgeries within the first 3 years of operation.  The event will also include a ribbon cutting to introduce the program's new partner, Dr. Tammy Shilling.  Northland Spay-Neuter opened in October of 2009 and averages 20 to 30 surgeries a day.  The program is supported in part by the Animal Allies Humane Society and area businesses.   The open house will run from 3:30 to 6 p-m and will feature refreshments and tours of the clinic.