A NEW FAMILIAL GLOMERULONEPHROPATHY IN BERNESE MOUNTAIN DOGS

Between 1989 and 1992, 22 Bernese mountain dogs (18 females and four m ales) aged between two and seven years, which had been suffering for s ome weeks from weight loss, anorexia, apathy, vomiting, polydipsia and polyuria, were examined. All of them had high blood urea nitrogen and serum creatinine concentrations, and many had hyperphosphataemia, hyp ercholesterolaemia, hypoproteinaemia and nonregenerative anaemia. All the dogs had very high protein: creatinine ratios in the urine, and ma croproteinuria was identified by sodium dodecyl sulphate gel electroph oresis. The immunofluorescent titres against Borrelia burgdorferi, mea sured in 19 of the dogs, ranged between 256 and 32,768. In all cases, membrano-proliferative glomerulonephritis with concomitant interstitia l nephritis was diagnosed. From an analysis of the dogs' pedigree it w as concluded that the glomerulonephritis of these Bernese mountain dog s was inherited as an autosomal recessive trait and that its expressio n was influenced by a second gene locus with a sex-linked dominance ex change.