Molecular and phenotypic characteristics of Salmonella enterica serovar 4,5,12:i:- isolated from cattle and humans in Iwate Prefecture, Japan.

A total of 15 isolates of Salmonella enterica serovar 4,5,12:i:- obtained from diseased cows and patients in Iwate Prefecture, Japan, were characterized to clarify the genetic basis of this serovar. S. Typhimurium- specific IS200 was detected from all the isolates. A 94-kb plasmid and the spvB gene were detected from all but one of the 15 isolates. The results of PCR mapping of the fljAB operon and its flanking regions indicate that there are deletions or mutations in this chromosomal region. These data suggest that the 15 isolates are monophasic variants of S. Typhimurium. Epidemiological relationships between the isolates obtained from cattle and humans were not suspected based on the comparison of data employing plasmid profiling and pulsed-field gel electrophoresis.

An aged bull with concurrent thyroid C cell carcinoma, adrenal pheochromocytoma and pituitary chromophobe adenoma.

A Japanese Black bull aged 20 years died following progressive loss of the body weight. Pathological examination disclosed multiple endocrine tumors including thyroid C cell carcinoma with metastases to the cervical lymph nodes and lung, adrenal pheochromocytoma and pituitary chromophobe adenoma in the pars distalis. The serum calcium content was as mildly low as 8.0 mg/dl at the terminal stage. The bull had daily ingested the ration containing 1.9 times the recommended calcium amount for 8 years and 120,000 units of vitamin D(3) for 5 years prior to death. The long-term dietary intake of moderately excessive calcium with vitamin D(3) might be related to the pathogenesis of the thyroid C cell carcinoma.

A piglet with concurrent polioencephalomyelitis due to porcine teschovirus and postweaning multisystemic wasting syndrome.

A piglet developed respiratory distress followed by difficulty in standing and unsteady gait. The lesions were characterized by polioencephalomyelitis with the predominant distribution in the brain stem, as well as lymphocyte depletion and histiocyte infiltration with cytoplasmic inclusion bodies in the lymphoid tissues throughout the body and interstitial pneumonia. Porcine teschovirus (PTV) antigens were found in the former lesions and porcine circovirus 2 (PCV2) in the latter two lesions. PTV genes were detected from the diencephalon. The results suggest that the piglet was concurrently affected with polioencephalomyelitis due to PTV and postweaning multisystemic wasting syndrome (PMWS) associated with PCV2. They also suggest that the immunosuppressive condition developing in PMWS may have facilitated the infection of the brain with PTV.

Application of restriction fragment length polymorphism analysis to simple and rapid genotyping of bovine viral diarrhea virus strains isolated in Japan.

The E2 regions of 177 bovine viral diarrhea virus (BVDV) strains isolated in Japan between 1957 and 2006 were analyzed for genotyping. The strains were classified into 8 genotypes (1a, 1b, 1c, 1d, 1e, 1f, So and 2a) based on the phylogenetic analysis. The restriction fragment length polymorphism (RFLP) analysis of the RT-PCR products using 6 selected enzymes (Apo I, Mly I, BstAP I, Pvu II, Ear I, EcoR V) disclosed the cutting patterns classified into 11 groups (I-XI), each of that consisted of strains belonging to a single genotype. Namely, groups-I and -II were composed by genotype-1a strains, groups-III and -IV by 1b strains, and groups-V and -VI by 1c strains. Other groups-VII, -VIII, -IX, -X and -XI comprised genotypes-1d, -1e, -1f, -So and -2a strains, respectively. The results suggest that the RFLP analysis can simply and rapidly differentiate the 8 genotypes of BVDV strains.

Field application of the combination of neutralizing test and virus isolation, so-called spot test, to detect herds including cattle persistently infected with bovine viral diarrhea virus.

To detect herds including cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV), application of the combination of neutralizing antibody detection and virus isolation, so-called spot test, were performed on sera of 3 calves selected from each of 26 farms. Nine farms were judged as positive because 64 or more antibody titers were detected from 2 or more calves or BVDV was isolated from one or more calves. PI cattle were detected from 8 of the 9 farms. The positive judgment on one farm was obtained only when the indicator virus used on the neutralizing test was genotypically identical with the isolate from the farm. These results suggest that the spot test can be effective in detecting herds with PI cattle and that the accuracy may be influenced by the genotypes of the indicator viruses.

Meningoventriculitis caused by Streptococcus pluranimalium in a neonatal calf of premature birth.

Pathological and bacteriological examinations were carried out on a neonatal calf that had developed nervous symptoms such as opisthotonus and blindness since it was born one month prior to full term. The principal lesions were characterized by fibrinopurulent inflammation of the meninges, choroid plexuses, and ventricular walls with limited extension to the subependymal parenchyma in the spinal cord. Purulent inflammation was also found in several visceral organs and tissues. Streptococcus pluranimalium was isolated from the brain and cerebrospinal fluid. These results suggest that the animal suffered from meningoventriculitis with septicemic S. pluranimalium infection.

A neonatal calf with concurrent meningoencephalitis by Enterobacter cloacae and enteritis by attaching and effacing Escherichia coli (O128).

A neonatal calf developed nervous symptoms followed by diarrhea. The principal pathological changes were fibrinopurulent meningitis with necrosis of the cerebral parenchyma, and attaching and effacing lesions in the intestine. Cerebral necrosis was frequently associated with vascular changes. Enterobacter cloacae was isolated from the brain and Escherichia coli (O128) from the intestinal content. These suggest that cerebral and intestinal lesions were caused by the isolated organisms, and that most necrosis of the cerebral parenchyma might be infarctive.

Identification of herds with cattle persistently infected with bovine viral diarrhea virus by virological evaluation of three calves.

For the identification of herds with cattle persistently infected (PI) with bovine viral diarrhea virus, 1,272 animals from 20 herds were subjected to serum neutralizing (SN) test using the Nose strain and virus isolation. Eighteen PI cattle were detected from 5 herds. On the phylogenetic tree based on the nucleotide sequences of the 5' untranslated region, the isolates from the PI cattle were classified into genotypes-1a or -1b. Of 3 unvaccinated calves aged 6 to 12 months selected from each herd, the probabilities of obtaining 2 or more non-PI cattle with SN antibody titers of 64 or more (P(SN)), one or more PI cattle (P(VI)), and either of the conditions (P(Total)) were calculated using the hypergeometric probability model. P(Total) for the 5 herds with PI cattle was 1.000. P(SN) for 3 herds with many PI cattle within the selected age group was as low as 0.500 or less, and P(VI) was as high as 0.886 or more. P(SN) in the 2 other herds with few PI cattle was 1.000, and P(VI) was as low as 0.375 or less. P(Total) in 13 of 15 herds without PI cattle was 0.000, and was 0.714 or 0.774 for the 2 other herds. These results suggest that herds with PI cattle can be predicted with high accuracy when both SN test and virus isolation are performed on only 3 unvaccinated calves aged 6 to 12 months selected from a herd.

Caprine enteritis associated with Yersinia pseudotuberculosis infection.

Yersiniosis was prevalent among a caprine herd during the late autumn of 2003 in Iwate Prefecture, Japan. The disease affected 29 of about 100 lactating goats, but not dried or nonparous goats, mature male goats or kids. Four animals died within an epidemic period of 20 days. Affected animals developed decreased milk production with subsequent watery diarrhea, neutrophilia with increased band forms and multiple microabscesses characteristic of yersiniosis in the intestinal mucosa from the jejunum to caecum as well as in the mesenteric lymph nodes. Y. pseudotuberculosis serotype III was isolated from intestinal contents and mesenteric lymph nodes. The organism was also cultured from clinically normal dried animals. The outbreak might have been precipitated by multiple stress factors, such as lactation, cold weather, Corynebacterium pseudotuberculosis infection resulting in abscess formation and tapeworm and coccidium parasitisms.

Genetic and antigenic analyses of bovine respiratory syncytial virus detected in Japan.

Genetic and antigenic analyses of bovine respiratory syncytial virus were conducted on 12 field strains from Tohoku and Hokuriku districts in Japan during from 2002 to 2004. On the phylogenetic tree of the nucleotide sequences of the glycoprotein region, the examined strains fell in the same cluster as the strain isolated in Nebraska and were classified as the subgroup III. The examined strains were subdivided into 2 lineages (A, B). Isoleucine 200 of the epitope domain was replaced by threonine as a feature of the lineage B strains. The examined strains showed the nucleotide sequence homologies of 88.3-93.3% with the known Japanese strains classified as the subgroup II and of 86.1-96.6% with those in the subgroup III. No significant difference was found on the neutralization index between the examined strain and the 52-163-13 phylogenetically similar to the Japanese vaccine one. The results suggest that the subgroup III strains have existed in Japan and that epidemics of the strains could be protected due to the present vaccination.

Fibrinonecrotic rhinitis caused by a concurrent infection of Fusobacterium necrophorum and Arcanobacterium pyogenes in a cow.

An 8 year-old cow showing severe dyspnea and nasal mucosal necrosis immediately after parturition was subjected to pathological examination. The principal lesions were fibrinonecrotic rhinitis, necrotic bronchopneumonia and renal infarction. Fusobacterium necrophorum biotype A and Arcanobacterium pyogenes antigens were detected in the nasal and pulmonary lesions. These results suggest that the lesions were caused by a concurrent infection of the detected bacteria and that the pulmonary lesions were caused by the aspiration of infectious materials from the nasal ones. Mucosal coagulative necroses observed as the initial lesions in rhinitis were frequently associated with multiple thrombosis. The findings might suggest that thrombosis played an important role in the development of the nasal lesions.

Occurrence of equine coital exanthema in pastured draft horses and isolation of equine herpesvirus 3 from progenital lesions.

During the period from 2001 to the following year, progenital diseases had been epidemic among the draft stallions and mares pastured together in Iwate Prefecture, the northeastern district of Japan. A stallion and 8 of 31 mares were affected in 2001, and 1 of 2 stallions and 10 of 36 mares in 2002. The clinical symptoms consisted of the formation of papules, pustules, ulcers and scabs on the progenital skin and mucosa in stallions and mares. In 2002, Equine herpesvirus 3 (EHV3) was isolated from 2 mares and the glycoprotein G gene of the virus detected from a stallion and 4 mares by polymerase chain reaction. Serum neutralizing tests showed that 12 of 38 horses, 10 clinically and 2 subclinically affected, changed to be positive for the EHV3 antibody. The results suggest that the horses were affected with equine coital exanthema (ECE) through coitus. Five mares with the antibody at the pre-pastured period may have been the possible origins of EHV3 infection in 2002, although the exact origin in 2001 remains unknown. The artificial insemination was performed for the prevention of ECE spreading through coitus on the pasture in 2003. There was no epidemic of the disease in 31 mares, although 3 mares with the antibody at the pre-pastured period showed the significant increase in the titers during the pastured period.