10. Tuberculosis en linfonódulos medianísticos medios. Los linfonódulos están
aumentados de tamaño y muestran múltiples tubérculos pequeños de tipo caseoso
45. Johne’s Disease:
What is it ?
Pronounced: “YO - knees”
A chronic bacterial infection .
Affecting primarily the intestinal tract but leads to
infection throughout the body.
Incurable chronic wasting condition.
Affects: cattle, deer, bison, sheep, goats, camels
rarely pigs & horses
Long incubation period: 2-10 years
Discovered in 1895 by Johne and Frothingham
46. Mycobacterium paratuberculosis
Bacterium
Related to tuberculosis
Very resistant/ hardy
River water 165 days
Tap water 520 days
Freezing temperature 245 days
Slurry storage 252 days
Survives in the feces for up to 1 year
Survives commercial pasterurization - 3% of milk cartons
Slow growing 3-4 months in lab
Shedding of the organism is sporadic
47. Johne’s Signs?
Signs:
95% of infected cattle show NO Signs !!
5% show weight loss, then intermittent diarrhea
Clinical signs in animals > 2 years old
Culled before diagnosed (10% of culls)
Herd signs:
One animal with chronic diarrhea then
another several months later.