Nephritis
General description
- Nephritis is a term used to describe damaged kidneys seen at the abattoir.
- An inflammatory, degenerative disease of the kidney.
- Prolonged damage causes kidneys to be shrunken, irregular and scarred. Recent damage causes swollen, discoloured or spotty kidneys (also referred to as ‘white spotted kidney’).
- Long-term, nephritis reduces growth rate/weight loss and it can lead to sudden or eventual death (weeks to months).
- Kidneys are condemned at the abattoir depending on the extent and spread of damage.
Cause
- Infections from marking wounds; poisonous plants e.g. soursobs; or toxins from some antibiotics and some fertilisers e.g. superphosphate.
Clinical signs
- Some animals may be mildly affected and show no signs of illness.
- Animals with chronic kidney damage may suffer from ill-thrift, pale gums, increased urination and sporadic deaths.
- Significant damage leads to decreased production, growth and/or death.
Diagnosis
- The cause of the nephritis first needs to be determined; this will require testing by a veterinarian.
Treatment
- Will vary depending on the cause and if it is sudden or chronic.
- Stock should immediately but slowly, be moved from known toxic areas.
Prevention
- Use sharp and clean marking equipment disinfected regularly, with a chlorhexidine-based disinfectant e.g. Hibitane.
- Avoid wet conditions, overcrowding, prolonged holding and separation of lamb and ewe.
- Choose a balanced ration introduced over 2 or more weeks.
- Prevent weeds by quarantining new sheep for 7 days and using weed deterrents, and provide adequate hay in weedy paddocks.
- Measure drench and antibiotic dosage rates accurately and use faecal egg counts to determine if drenching is required.
