A ll ungulates carry strains of pasteurella. Experimentally, elk, deer, mountain goats, cattle, horses and llamas that associated with bighorn sheep did not result in pasteurella problems with bighorns. A large number of strains are known to exist, of which only a few are deadly to bighorn sheep. There are some strains of pasteurella carried by domestic sheep that are not lethal to bighorn sheep. Y oung bighorn rams commonly travel outside their primary range.
Domestic sheep can stray from the main flock.
Because of these habits, buffers, unless very large, have often failed. A lthough attempts have been made, no effective vaccine exists that will prevent bighorn sheep from developing pneumonia after contact with harmful strains of pasteurella. If one were developed, it would be difficult to administer to free ranging bighorns. If you see bighorn sheep in close proximity of domestic sheep, it is extremely important to contact your nearest Wildlife Department Office as quickly as possible. Wildlife Department personnel may need to remove bighorns from your area to prevent the spread of potentially fatal disease to the herd.