Learning to draw blood from a pig is no simple matter. In truth, the technique is not so much complex as it is laborious. During a clinical skills rotation to the swine barn, my classmates and I took turns snaring sows and drawing blood from them, the latter activity colloquially referred to as “bleeding” the pigs. Though not a big fan of that designation, I acknowledge that it is an essential function of a swine vet or animal caretaker in order to get a blood sample.
First, the pig must be restrained. If the individual of interest is a piglet, it should be held in ventrodorsal recumbency. If it is, say, a 300-lb sow, it should be snared. This action is supposedly not painful, but it definitely stresses the animal, which manifests from the sound the snare elicits. I cannot adequately describe it, but suffice it to say that it is the most awful sound in the world. A casual listener would think that we were massacring the pig, but rest assured, this is most definitely not the case. Next, a needle is deftly inserted into the neck, cranial to the sternum, and at an angle to the right of the animal’s midline. It is somewhat scary to think that we students are expected to draw blood from the cranial vena cava, but that is the standard operating procedure. It can be completed within a matter of seconds, or minutes, depending on how long it takes to explore the cervical region in order to locate the vena cava and see blood enter the syringe. All in all, it’s an important procedure but may take a lot of practice, especially if one is used to working in quiet conditions.