Each year, every dog enrolled in the Morris Animal Foundation Golden Retriever Lifetime Study undergoes a comprehensive physical exam, including a blood draw that takes more blood from the dog than a routine blood draw. This prompts many participants in the study, from pet owners to veterinary technicians, to ask “Why do you need to take such a large blood sample? Is it safe? How much blood can you take from a dog?”
Most routine blood panels can be run on 10-15 ml of blood. However, the study requires that 56 ml of blood be drawn once yearly; that is the equivalent of 2 fluid ounces, about 4 tablespoons. Even for our younger participants, this amount of blood is safe as long as the pup is healthy.
In fact, a healthy, 60-pound dog can donate almost 200 ml of blood before we get concerned about removing excessive amounts. Canine blood donors can give approximately 500 ml as they are typically given IV fluids following donation to replace lost fluids.
The reason we collect so much blood for the Golden Retriever Lifetime Study is for the more specialized testing and banking involved in study participation. Some blood is sent to the laboratory for routine bloodwork: red and white blood cell counts, blood chemistries that check out liver and kidney function, electrolytes such as sodium and potassium, and hormones such as thyroid. These tests are run immediately, and reported back to the veterinarian, and any leftover samples are frozen.
The remaining samples are processed and stored in special ways at a biorepository for future testing. For example, one sample tube is specially stored for future DNA analysis. This sample is stored at an especially low temperature to keep the DNA intact for years.
All the blood samples collected will provide invaluable information not only for current researchers, but for researchers in the future as well. So, the next time your pet is required to give a sample, remember that with each collection you and your hero are advancing animal health, one drop of liquid gold at a time!