Transmission of Brucellosis from Elk to Cattle and Bison, Greater Yellowstone Area, USA, 2002–2012
Figure 2. . Minimum spanning tree generated from variable number tandem repeat (VNTR) data for 348 Brucella abortus isolates in the National Veterinary Services Laboratory database. Each sphere, or node, represents a unique VNTR type. Nodes are color coded according to the source of the isolate, and segments of nodes represent isolates from different animals with the same VNTR profile. The numbers represent the herd designations as indicated in the Table (note that herd no. 2 is not represented in this figure).