A case of sheep-associated malignant catarrhal fever (SA-MCF) was observed in one Japanese Black cow on a beef ranch where cattle and sheep were kept together. The animal had pyrexia, anorexia, and a cough and died in 5 days. Histological investigation showed angiitis in the major organs of the dead animal. Ovine herpes virus-2 (OvHV-2) genes were detected in cells from these organs. None of the 25 other head of cattle kept with the affected one showed similar symptoms. Polymerase chain-reaction checks of peripheral-blood leucocytes (PBL) showed OvHV-2 genes in 10 out the 25. Successive checks made at 2-month intervals over 11 and 13 months detected OvHV-2 genes consistently in the PBL of 2 animals. This suggests that at least 10 head of cattle were subclincally affected by SA-MCF and that 2 head were persistently infected by OvHV-2 during the observation period.
As a result of genotypic examination, a 1.5-month-old Japanese Black calf was diagnosed as homozygotic for Claudin-16 (CL-16) deficiency. The animal suffered from watery diarrhea, dehydration, dysstasia, and clonic spasms. Hematological analysis revealed renal damage, hypocalcemia, and hypomagnesemia. Urinary sediment included many renal tubular epithelial cells. Necropsy showed both kidneys to be small. Histological examination showed degeneration, necrosis, and desquamation of renal tubular epithelial cells, marked thickened renal-tubule basement membranes, and marked interstitial fibrosis. These conditions may account for the abnormal formation of tight junctions between renal tubular epithelial cells caused by CL-16 deficiency.
Clinical investigations of 15 dogs serologically positive for canine leptospirosis showed that many animals with positive titers lived in the Fukuoka urban area. More than half of the infected dogs were such miniature or toy breeds as shih tzu, miniature dachshund, and Maltese. Their ages ranged from 3 months to 14 years without deviation. Most of their clinical signs involved disorders of the digestive system: anorexia for more than 3 days, vomiting, and diarrhea. Although they are thought to be typical of canine leptospirosis, renal features, liver-function disorder, and jaundice, were rarely observed. Neurological symptoms including motioninduced pain and general tonic convulsions were observed in a few cases. High titers of antibodies against L. icterohaemorrhagiae and L. hebdomadis were observed. The presence of pyometra in three of five unspayed bitches suggested that this condition may conceal leptospirosis.
We examined the prevalence of Arcobacter and Campylobacter among house rats trapped in buildings in Yokohama between July 2000 and June 2001. All of the trapped animals (n=157) were identified as Rattus rattus. Arcobacter was detected in 48 (30.6%) of the 157 animals. No thermophilic Campylobacter was detected from any of the animals in this investigation. There were no statistically significant differences among seasonal detection rates. Of 148 Arcobacter isolates, 145 were identified as A. butzleri. The remaining three strains isolated from one rat demonstrated biochemical characters and DNA sequences in part of the 23S rRNA gene different from those in other Arcobacter species. This suggests the possibility of the strains being new Arcobacter species close to A. butzleri. Thes present study showed that some house rats living in buildings in downtown Yokohama harbored Arcobacter species at a high rate.
PIXE assays performed to survey heavy-metal contamination in liver, kidney, and hair samples collected from 42 Japanese black bears (male: 24, female: 18) in Iwate Prefecture detected chromium, manganese, iron, cobalt, copper, zinc, selenium, molybdenum, cadmium, lead, etc. Cobalt concentrations in the bear tissues were more than 10 times higher than those in human or several other animal species. In two bears, extraordinarily high concentrations of zinc, especially in the hair, suggested excess exposure to this element. Mean cadmium concentration in the liver was 0.20 mg/kg, in the kidneys 9.16 mg/kg, and in the hair 2.10 mg/kg. In no case cadmium concentrations exceeded those in normal healthy adult Japanese human beings. Whereas hepatic lead concentrations were below lmg/kg in most animals, in three bears they were above 2mg/kg. These high lead concentrations may be caused by environmental contamination in the Iwate area.