In this study, we reported that two cases of ExPEC (extra-intestinal pathogenic Escherichia coli) infection in calves occurred in Yamagata Prefecture, and analyzed the cellular impairment of the isolates using cultured cells. The autopsy similarities between the two cases included hemoid hydrothorax and bleeding from the heart, lungs, omentum, and intestines. Each case included bleeding from the cerebrum, liver, kidney, and spleen. ExPEC was isolated from each organ in both cases. In the Hep-2 cells inoculated with ExPEC, which entered the cells and caused cell death through desquamation and cytoplasmic damage. These results suggest that ExPEC impair cells by invasion, and cause tissue damage through bleeding.

We evaluated urine protein using the dip-stick (DP) method and the urine protein/creatinine ratio (UPC) determined with a dry-chemistry analyzer (dry method), and then compared the results with the UPC determined by liquid-treating method used on 30 dogs and 30 cats. In both dogs and cats, the urine samples determined to be negative by the DP method were non-proteinuric (＜0.2 in UPC). However, the samples estimated as ±, ＋or 2＋by DP method involved non-proteinuric, borderline proteinuric (dogs: 0.2 to 0.5; or cats: 0.2 to 0.4 in UPC), and proteinuric (dogs: ＞0.5 or cats: ＞0.4 in UPC) samples. Therefore, proteinuria needs to be confirmed in these urine samples by determining the UPC. The UPC determined by the dry method was significantly correlated with the liquid-treating method both in dogs and cats, and could be used in place of the UPC determined by the latter. The UPC determined by the dry method was higher than that determined by liquid-treating method. Thus, the transformation formulas (y＝0.8851x‐0.1316 in dogs; and y＝0.7227x‐0.0093 in cats) might be useful for converting the data determined by the dry method to that determined by the liquid-treating method.

Changes in the immune status in response to canine distemper virus (CDV), canine parvovirus type 2 (CPV‐2), canine adenovirus type 1 (CAdV‐1), and canine adenovirus type 2 (CAdV‐2) over the course of several years after vaccination were examined using sera obtained from 178 dogs older than 24 months. Our results showed that the decline in the effects of the vaccine and antibody levels were associated with the number of years that had elapsed since vaccination in all four virus groups. In addition, the coefficient of variation for the antibody level was markedly elevated in the CDV, CAdV‐1, and CAdV‐2 groups two years after vaccination. Based on these findings, we concluded that the reduced antibody level shows a more rapid rate of decline with the passage of time after vaccination, and thus it is conceivable that individual differences in the immune status will be greater. Therefore, it is considered necessary to regularly monitor the immune status by conducting antibody tests on dogs for which vaccination should be avoided for reasons such as immune-related diseases.