Hunter Surveillance Blood Kits
Hunter Surveillance Overview
Each year the Wyoming Game and Fish Department (WGFD) monitors the distribution of brucellosis within the state’s elk populations by requesting hunters to collect blood samples from their harvested animal. Surveillance is generally concentrated in elk herds that surround, but do not use state or federal feedgrounds. Nearly a quarter of the state is surveyed each year, eventually providing coverage over the entire state. Approximately 11,000 blood collection kits are assembled and mailed to hunters successful in acquiring limited quota elk licenses within target surveillance areas. In general, hunters return between 1,200 and 1,500 blood samples to the laboratory, of which approximately 60% are suitable for testing (samples often freeze in the return mailing, rendering them untestable).
Since 1991 over 12,500 elk blood samples have been analyzed for brucellosis. To date, this disease has only been documented in the western half of Wyoming, with prevalence levels between 0-4% in the southern herd units (South Wind River, West Green River) surrounding feedgrounds, and between 1-23% in the corresponding northern herd units (Clarks Fork, Gooseberry, Cody, and Wiggins Fork). The northern units have been opportunistically monitored for the past several years, where historical prevalence was similar to the southern herd units, but for unknown reasons dramatically increased in early 2000.
In 2012, two sero-positive elk were discovered on the west side of the Bighorn Mountains; two additional positives were found in the same area in 2013. Three additional positive elk were documented in 2014. Intensive surveillance of the Bighorn Mountains will continue for the forseeable future. The documentation of seropositive elk outside of the Greater Yellowstone Area (GYA) is of great concern to both livestock and wildlife managers.
Blood sample collection from hunter-killed elk
As soon as you reach your harvested animal, it is import to collect the blood sample as soon as possible. It is reccommended that you wear gloves when collecting your blood sample. There are three locations on an animal that are very easy for blood collection.
- The most obvious location is the jugular vein in the neck. To open the jugular, simply make a deep cut on the bottom of the neck in the area of the windpipe. If the animal hasn’t been dead for more than 5 or 10 minutes, there should still be plenty of blood in the veins. To fill the tube, simply remove the cap and allow the blood to flow into the tube, while avoiding any hair or other foreign matter from contaminating the sample.
- If you are going to quarter the animal, you can also collect blood from the femoral artery when removing the rear quarter. To find the artery, make a cut where the rear quarter meets the abdomen or belly, and continue cutting until you reach the joint where the femur meets the pelvis. While making this incision, you will sever the femoral artery and blood should gush from the area. Again, fill the tube with the flowing blood while avoiding foreign material that could contaminate the sample.
- The final place to collect an easy blood sample is from the chest cavity. If the animal has been shot in the heart or lungs, the chest cavity should have lots of pooled blood. When gutting your animal, open up the chest cavity by splitting the ribs down the center line (brisket), or if the animal is quartered or being boned out, you can access the cavity by removing a rib, or the diaphragm. Fill the tube by dipping into the pooled blood. It’s okay if the blood has started to clot; just do your best to fill the tube as full as possible while gently handling the clotted blood.
Once the tube is full, replace the cap firmly, wrap the tube in the paper towel and place in the plastic bag. Fill out the information card and include with the blood sample in the postage free mailer. Adhere the enclosed business reply label over the front of the shipping box and drop in the nearest post office box after leaving the field. It is very important to keep the blood sample cool, but protect it from freezing. Please send your sample into the laboratory (or drop off at the nearest Game and Fish office) as soon as possible. If you are hunting in the Bighorn Mountains, you may also see a cooler like the one below. You can leave your blood sample in there as well.