Johne’s Disease
Paratuberculosis)
- most often noticed in animals over 1yr of age
- progressive weight loss to emaciation
- may be diarrhea and soiling of fleece on hindquarters
- poor lamb performance
- affected animal dies after a period of illness
Cause/Transmission
- intestinal damage due to bacterial infection, leading to inability to absorb nutrients
- transferred by contact with infected animal (feces, colostrum, placenta)
- bacteria can survive for 2yrs in environment
Treatment
- none, cull suspected cases
Prevention
- blood or fecal sample flock and cull positives (tests not always accurate)
- maintain sanitary barn conditions
- buy breeding stock from a known reputable source
- consider testing a percentage of cull animals at diagnostic lab to determine incidence in flock (high incidence depopulation Accuracy of test may be questionable – consult with your vet. and restocking is an option).
Caseous Lymphadenitis
(Pseudotuberculosis)
- most often seen in animals over 6 months
- signs depend on where disease manifests itself, may be no external signs but poor condition: external: lymph nodes of neck, under jaw, face, shoulder are enlarged, often abscess (open pus-filled sores) internal: abscesses form in lungs and other internal organs (respiratory distress)
- general weight loss, poor production
- sudden death may occur
Cause/Transmission
- bacteria enters through cuts and abrasions in skin
- transmitted by direct contact between animals and contaminated shearing equipment
- bacteria can survive for months in the environment
Treatment
- culling of infected animals recommended
- abscesses will heal, but reoccur
Prevention
- very common disease, often spread by purchasing infected breeding stock
- vaccine available; treat new stock before entering flock (often given in 3 or 6-way shot with closridial vaccines)
- avoid cutting animals with shears, disinfect shears between animals
- shear groups less likely to have the disease first (e.g. young animals before older animals)
Dental disease
- most often in older sheep (3 yrs and older)
- decreased appetite
- weight loss
- no signs of neurological disorders (not uncoordinated etc.)
- tooth loss, bad breath, poor gums
Cause/Transmission
- infection by various types of bacteria
- cause unknown, maybe related to calcium:phosphorous imbalance in diet and/or excessively hard feeds (roots etc), possible genetic link
Treatment
none
Prevention
- check Ca:P balance in diet
- good quality feed
- purchase young stock and check teeth before purchase
- check for tooth loss in adults as part of pre-breeding check (with condition scoring and udder check)
