Bags of sheep blood

Bags of sheep blood

 Sheep flock
Sheep raised for bleeding

agar plates
Blood agar plates
National Cancer Institute image


    A bloody good idea

    First blood transfusion
    The first fully-documented blood transfusion was carried out by Dr. Jean Baptiste Denys on June 15, 1667. He tranfused the blood from a sheep into a 15-year old boy who later died. The doctor was charged with his death. The first successful blood transfusion did not occur until 200 years later in 1818. By this time, doctors had discovered mixing blood types posed serious health risks.

    Sheep as blood donors
    Different kinds of culture media can be used to isolate microorganisms and diagnose infection. Horse and sheep blood are the most widely used animal blood products in culture media. The choice of the animal is largely traditional, with the U.S. and much of continental Europe preferring sheep blood. While some sheep blood is obtained from abattoirs, some sheep are raised specifically to produce blood for biomedical purposes.

    Sheep as drug factories
    Protherics is a drug development company specializing in critical care products derived from sheep polyclonal antibodies. The raw material (serum) for their products comes from their sheep flock in South Australia. The 4,500 strong first cross Merino/Border Leicester wethers are immunized every four weeks for 18 weeks to produce antibodies against either a snake venom or particular drug.

    At 18 weeks, they reach their peak antibody level and are then bled every four weeks in a fashion similar to what happens at the Red Cross. Animals are first bled at about 20 months of age and generally remain in the research flock until they are 7.5 years old.

    Once the blood has been harvested, it is transported to the manufacturing facility where the bags are spun in centrifuges to separate the red blood cells from the serum, containing the antibodies. It is then filtered, frozen, and exported to the parent company manufacturing site in Wales. The antibodies are extracted and purified to form the end product.

    Rattlesnake anti-venom
    Products include North American rattlesnake anti-venom, an antidote for overdoses of the heart drug Digoxin, CytoFab™ for the control of sepsis-syndrome or septic shock, a Prolarix™, a novel anti-cancer drug. Protherics is one of a handful of companies worldwide that uses sheep to produce polyclonal antibodies.


Last updated 19-Apr-2021
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