Nephrosis occurs sporadically
in young lambs between two and four weeks-old, and in growing lambs
between two and four months-old; cases in the latter age group
often appear after an outbreak of coccidiosis and/or nematodirosis.
The cause has not been resolved although a toxic insult is
considered the probable aetiology.
Occurs sporadically in
Follows an outbreak of
coccidiosis and/or nematodirosis
A toxic insult is
considered the probable cause
Fig1: Nephrosis in a growing
Fig 2: Nephrosis
affecting a growing lamb (left) compared to normal sized lamb
Fig 3: Nephrosis
affecting a growing lamb (right) compared to its normal sized twin
Affected lambs are very
depressed, do not suck, and appear thirsty as they frequently stand
with their heads over a water trough but drink little. The lambs
appear gaunt with little abdominal content and rapidly become
emaciated. The rectal temperature is normal. There is often
evidence of faecal staining of the perineum. The faeces are soft
Fig 4: Affected
lambs are very depressed, do not suck, and appear thirsty as they
frequently stand with their heads over a water
Fig 5: Lamb with
nephrosis drinking from a field drain (see
Fig 6: Field
drain used as a water source by the lamb above - no other lambs
were ever seen drinking in this manner.
The important differential
diagnoses your veterinary surgeon will consider include
The diagnosis is based upon
the clinical findings and results of tests your veterinary surgeon
may undertake. Diligent stockmanship will identify affected lambs
which should be euthanased once they have failed to respond to
anthelmintic/anticoccidial/antibiotic therapy. Necropsy reveals
very pale swollen kidneys.
Fig 7: Necropsy
reveals very pale swollen kidneys.
Fig 8: Necropsy
reveals very pale swollen kidneys (top set) with a pair of normal
There is no treatment and
affected lambs are euthanased for welfare reasons.
There are no recognised
control measures. Control of nematodirosis (clean grazing or
appropriately-timed preventive anthelmintic treatment) and
coccidiosis (clean environment and possible preventive
treatment/in-feed medication) are detailed on the NADIS