In a batch of lambs of under 12 months of age, renal whitish lesions were observed in a 20% of the animals.

Histologically, the lesion corresponded to a moderate, subacute to chronic, multifocal interstitial nephritis and of a chronic pyelonephritis. This is most likely the chronic phase of a purulent nephritis (of bacterial origin) but this cannot be confirmed histologically.

Microbiological culture failed to isolate any infectious agent, probably due to the chronicity of the injury or the possibility that the animals had been treated with an antimicrobial drug.

Nephritis can be:

  • Hematogenous: as in the case of an adenovirus infection or bacteremia due to, for example E. Coli, Salmonella and Brucella.
  • Urogenous: in this case it is associated to pyelonephritis and the origin might be ascending urinary bacterial infections such as those caused by E. Coli, Staphylococcus, Proteus, Pseudomonas and Corynebacterium renale.
Whitish spots that delve into the parenchyma.

Whitish spots that delve into the parenchyma.