For Hub City Times

MARSHFIELD — The city of Marshfield Parks & Recreation Department has announced the death of the male bighorn lamb born July 8 at Wildwood Zoo. With the help of the Marshfield Veterinary Service, it has been determined that the lamb was infected with Pasteurella multocida resulting in pneumonia. This is one of the most common causes of pneumonia in sheep and is one of the largest threats to wild bighorn sheep populations.

There are many contributing factors, mostly environmental, that predispose a sheep to contracting pneumonia. Any extreme or rapid changes in climatic conditions or stressful situations can play a factor. The recent hot and humid weather likely played a role in the lamb’s infection.

The first sign of the disease within a flock is typically the death of the lambs. The mortality rate for infected animals ranges from 50 percent to 90 percent and is even higher in newborns. Pasteurella multocida bacteria are susceptible to common antibiotics. Both Rocky and the ewe were treated with these antibiotics following infection of the lamb, and neither is currently showing signs of infection. This particular strain of bacteria can be transmitted from domesticated animals, such as dogs, cats, and other sheep and some wildlife species.

The ewe bighorn sheep was acquired earlier this year as a breeding animal and companion to Rocky. She was purchased from a breeder in Montana through a partnership with the Wildwood Zoological Society. Zoo staff hopes that Rocky and the ewe will pair up and have more lambs in the future.