There are many occasions in which a producer may wish to draw blood from a sheep or goat. Blood sampling is not difficult with some experience. Blood tests can provide valuable information on the health status of individual animals.
To assist producers with this task, Purdue University has written a fact sheet explaining and showing how to collect a blood sample from a sheep. The five-page fact sheet is in PDF format and is entitled Blood Sampling in Sheep.
One of the most common uses of blood sampling is to determine scrapie genotype. A sheep's genotype (DNA) determines whether or not it will get scrape IF it is exposed to the infective agent. They are still looking for resistant genotypes in goats.
Blood testing is also a tool for eradicating OPP and CAE from a flock or herd.
Sheep @ Purdue University