A hobby farmer cared
for a "closed flock" of 15 ewes. The only herd addition was made 2 years
earlier when she bought a ram from a large show flock.
A 2 year
old Clun Forest ewe had not been doing well for about 3 months.
Her dam and her own lamb were also thin. She had been losing weight,
suffered periodic bouts of diarrhea but her appetite was good and
she did not have a fever. The farmer was concerned about parasites
- in fact "stomach worms" were diagnosed and treated but
she did not improve. A fecal culture for M. paratuberculosis
was negative. The ewe was segregated from the flock and was euthanized
shortly thereafter when she became too weak to stand.
(term for an autopsy on animals) the Johne's disease diagnosis was
confirmed. Pathologic lesions consistent with M. paratuberculosis
were found throughout the gastrointestinal tract and the organism
was isolated from numerous tissue sites. An AGID test was weakly
slaughtered the dam, ram and lamb. She tested her entire flock by
fecal culture - no isolations of M. paratuberculosis were
made. No further cases of Johne's disease have appeared in the last
some situations, the source of the infection will never be determined.
negative test result (fecal culture) may not mean that the animal
is free of infection.
health problems may exist in addition to Johne's disease (e.g.
aggressive test-and-cull approach can control the spread of