After oral challenge of the pathological prion protein, the causative agent of bovine spongiform encephalopathy, the pathogen was first detected in the distal ileum and then deposited in the brain. The present study aims determining the possible neuronal transporting pathways from the ileum to the brain in the cattle using a tracer protein. After horseradish peroxidase was injected into the wall of the distal ileum in the calf, almost all labeled neurons were detected in the celiac and cranial mesenteric ganglion complex. Only a few labeled neurons existed in the caudal mesenteric ganglion and the paravertebral ganglia. They were sympathetic postganglionic neurons. In the dorsal root ganglia T5 to L4, some sensory neurons were found to be labeled. Only a small number of parasympathetic preganglionic neurons were labeled in the dorsal motor nucleus of the vagus nerve. No labeled sensory neurons were found in the nodose ganglion. These results suggest that the pathological prion protein is mainly transported to the spinal cord and brain via the sympathetic nervous system and partially via the sensory neurons in the dorsal root ganglia. The vagus nerve does not seem to contribute to the transport of the pathogen from the ileum directly.

View full abstract

Effects of the collagen oligopeptide (COP) were examined by its repeat injection into the inflammatory rabbit Achilles tendon (Tendo calcaneus communis), in which tenositis was induced by injection of bacterial collagenase. COP was evaluated 5 times over a period of 3 weeks to 1 month after injection of collagenase. At 1 month after treatment, the therapeutic effect of COP was evaluated by examining the structure of collagen fibrils, amount and components of glycosaminoglycans (GAGs) and matrix metalloproteinases (MMPs), and compared with the saline injection, control, and normal groups. The Achilles tendon of rabbit in the control group (no COP injection) and saline injection group showed a notable increase in the number of fine collagen fibrils, a change in GAG composition and increase in the amount of pro-MMP-2, indicating the weakening of the tendon. In contrast, the size distribution of collagen fibrils, GAG composition and the amount of pro-MMP-2 was similar to those in the normal group. These results suggest that COP injection promotes healing processes of the tendon injury.

View full abstract

In the present study, we compared differences in ionized calcium-binding adapter molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) immunoreactivities for microglia and astrocytes, respectively, in the hippocampus of the seizure-resistant (SR) and seizure-sensitive (SS) gerbils. The density of Iba-1 immunoreactive microglia in the hippocampal CA1 region (CA1) and dentate gyrus (DG) of the SS gerbil was higher than that in the SR gerbil, and many Iba-1 immunoreactive microglia in the SS gerbil were hypertrophied in morphology. In contrast, we could not find significant difference in the density of GFAP immunoreactive astrocytes between the SR and SS gerbils. This result indicates that Iba-1 immunoreactive microglia in CA1 and DG of the SS gerbil are activated compared to those in the SR gerbil.

View full abstract

Eight isolates of infectious bronchitis virus (IBV) were obtained from various prefectures in Japan during 2003-2007 and were genetically analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) coupled with direct sequencing. These IBV isolates were classified into three genetic groups, including two that have already been reported (JP-I and JP-III). The remaining group is related to the 4/91 (also known as 793/B) type, prevalent mainly in European countries, and has not been identified in Japan until now.

View full abstract

Brucella canis, a facultative intracellular pathogen, is the causative agent of canine brucellosis. The diagnosis of canine brucellosis is based on bacteriological examination and serological methods including agglutination and gel diffusion tests. In this study, recombinant B. canis Cu-Zn superoxide dismutase (SOD) was used as an antigen for the enzyme-linked immunosorbent assay (ELISA). The recombinant SOD showed a specific reaction with serum infected with B. canis in Western blotting and ELISA. These results suggest that ELISA using recombinant SOD is useful in screening for canine brucellosis.

View full abstract

Adrenal diseases are quite common in Japanese pet ferrets; however, there have been no reports concerning the epidemiology of ferret adrenal disease in Japan. The purpose of this study was to collect epidemiological data on ferret adrenal disease in Japan by sending a questionnaire to veterinarians throughout Japan. Among the 521 cases that met the criteria for this study, 307 were adrenocortical carcinoma (58.9%), 117 were adrenocortical adenoma (22.5%) and 87 were adrenocortical hyperplasia (16.7%), respectively. Sex, clinical signs, concurrent diseases, age and the sites of the affected adrenal gland in these cases were similar to those reported in North America. Most pet ferrets in Japan are imported from North America, and their husbandry in Japan is similar to that in North America, which may be the cause of the similarity in ferret adrenal disease between North America and Japan. Because a difference in the incidence of ferret adrenal diseases among countries has been reported, further research is necessary to investigate the factors related to the similarities and how to decrease the incidence of adrenal diseases in ferrets in Japan.

View full abstract

A 6-month-old male crossbred dog weighing 0.78 kg was presented with acute bilateral immature cataracts, intermittent diarrhea and growth retardation. The clinical manifestations and laboratory findings were suggestive of concurrent juvenile diabetes mellitus (DM) and exocrine pancreatic insufficiency (EPI). Moreover, the DM was associated with a decreased level of serum insulin-like growth factor I. Histological examination revealed a markedly lower number of pancreatic islets and acinar cells. This case shows that juvenile-onset DM can occur simultaneously with EPI and result in growth retardation, acute cataract formation and a high cortisol concentration.

View full abstract

Infection with Encephalitozoon cuniculi in rabbits frequently exists as a chronic, latent infection, and only a percentage of infected animals develop clinical disease. This study presents a seroepidemiological study of E. cunicucli infection in 337 pet rabbits collected from 20 prefectures in Japan in 2006 and 2007, using enzyme-linked immunosorbent assay (ELISA) capable of measuring IgG and IgM antibodies. These rabbits were divided into the following four groups: healthy and isolated rabbits (n=74, group I), healthy and companioned rabbits (n=121, group II), neurologically diseased rabbits (n=105, group III), and other diseased rabbits (n=37, group IV). Using ELISA for IgG antibodies, the highest detection rate, 81%, was seen in group III, the second highest, 75.2%, in group II, and the lowest, 29.7%, in group I, which was significantly different to the other groups except for group IV (43.2%). On the other hand, when ELISA was used for IgM antibody detection, 14-40% of rabbits in the four groups were also observed to have anti-E. cuniculi IgM. This study demonstrated high seroprevalence of E. cuniculi in not only neurologically diseased rabbits but also healthy and other diseased rabbits.

View full abstract

We previously identified two cDNAs from the midgut of adult Haemaphysalis longicornis that encode asparaginyl endopeptidases/legumains, HlLgm and HlLgm2. Functionally, both recombinant HlLgm and HlLgm2 efficiently digested blood proteins, haemoglobin and bovine serum albumin. Here, we investigated the expression profiles of legumain genes in the developmental stages in the life cycle of H. longicornis and in different tissues of adult ticks. Both HlLgm and HlLgm2 were well expressed in larvae, nymphs and adults. Legumain transcripts were expressed specifically in the midgut and were localized in some digestive vacuoles of gut epithelial cells. Furthermore, expression of either transcript was up-regulated by blood feeding in larvae and nymphs, suggesting the important roles of legumains in blood feeding and blood-meal digestion in ticks.

View full abstract

A cow, presenting with lameness with atrophy of the right supraspinatus and infraspinatus muscles, was clinically diagnosed with suprascapular nerve paralysis. Histological examination revealed necrosuppurative lesions with Gram-positive cocci arranged in chains in multiple organs, including the cardiac valves, lungs, muscles, joints, brain, cerebral and spinal meninges. Spinal meningitis progressed into the roots of the right 6th to 8th cervical nerves. The suprascapular nerve showed partial loss of nerve fibers in the periphery, and innervated muscle fibers were atrophied. Bacterial culture of the cerebrospinal fluid revealed the presence of Streptococcus pyogenes. From these findings, the suprascapular nerve paralysis in this case was considered to result from meningoradiculitis associated with systemic streptococcal infection. This is a rare bovine case of suprascapular nerve paralysis due to central nerve damage of infectious cause.

View full abstract

A 9-month-old male Japanese domestic cat showed pleural effusion, ascites, azotemia, hypoproteinemia and severe proteinuria. Histopathology of the percutaneous renal biopsy specimen revealed that all glomeruli showed intense mesangial hypercellularity with an increased mesangial matrix and thickening of the capillary walls, resulting in lobular accentuation of the glomerular tufts. Frequent duplication of the capillary walls was also observed. Immunostaining for α-smooth muscle actin distinctly revealed mesangial interposition. Diffuse global and linear deposition of C3 and IgG was observed mostly along the peripheral capillary loops. Electron microscopy confirmed frequent circumferential mesangial interposition and subendothelial dense-deposits in the glomerulus. The glomerular lesion was consistent with human membranoproliferative glomerulonephritis type I, and might be a rare case that developed at young age.

View full abstract

The black nodule measuring 1 cm in diameter developed in the base of nail of an 8-year-old Japanese domestic male cat. Histological examination of the excised nodule revealed a granulomatous lesion extending from the epidermis to adjacent bone. The lesion was consisted of diffuse infiltration of macrophages with epithelioid cells and multinucleated giant cells. These macrophages contained a few to numerous yeast-like brown pigmented fungus cells with a spherical shape and dark thick wall. The PCR amplification with universal primers of the 28S ribosomal RNA gene yielded a 628-bp fragment and the direct sequence confirmed that the diagnosis of the lesion was phaeohyphomycosis caused by the pathogenic dematiaceous fungus, Exophiala jeanselmei.

View full abstract

This is the first report regarding isolation of Salmonella from cecum samples of buffaloes and pigs and characterization of the isolates in Laos. The organisms were isolated from 8% (4/50) of buffaloes and 76% (37/49) of pigs. In buffaloes, 3 animals harbored serotype 9,12: -:1,5, and 1 animal harbored both S. Derby and S. Javiana. In pigs, the most predominant serotypes were S. Derby (51%) followed by S. Anatum (45%), S. Weltevreden (15%) and S. Stanley (5%). The buffalo isolates were susceptible to the antimicrobials tested, whereas the pig isolates showed 10 resistance patterns to 1-5 antibiotics. Of the 59 pig isolates, the resistance rates to tetracycline, streptomycin, ampicillin, sulfamethoxazole-trimethoprim, chloramphenicol, amoxicillin-clavulanic acid and nalidixic acid were 24%, 22%, 14%, 5%, 2%, 2% and 2%, respectively. The results suggest that pigs and buffaloes harbor Salmonella, with a higher prevalence especially in pigs, and all the isolates showed sensitivity to cefotaxime, norfloxacin and ciprofloxacin.

View full abstract

SART-1, a squamous cell carcinoma (SCC) antigen recognized by cytotoxic T lymphocytes, has been useful in human cancer therapy. The SART-1₂₅₉ peptide is a potential candidate for vaccine. The present study examined an orthologue of the mRNA coding this peptide in canine SCCs. Specimens were obtained from seven canine patients with SCC, and the mRNA was isolated from the samples. The SART-1 and beta-actin genes were amplified by reverse-transcription polymerase chain reaction, using the isolated mRNA as a template. Canine SART-1 was amplified in six of the seven specimens, while beta-actin was detected in all the samples. In dogs, carcinomas expressing SART-1 could be a target for cytotoxic T lymphocyte mediated immunotherapy.

View full abstract

Prior to euthanasia, brain magnetic resonance imaging (MRI) was performed for a five-year-old male Yorkshire Terrier following portosystemic shunt (PSS) surgical attenuation. Hyperintensity was observed on T1W images of the lentiform nuclei. Trace elements in this area were measured by inductively coupled plasma atomic emission spectrometry. The manganese concentration in the lentiform nuclei was four times higher than that in the control group. Therefore, the manganese accumulation would be the substance that causes the hyperintensity on T1W images of the lentiform nuclei in PSS dogs.

View full abstract

A total of 130 animals (82 cattle, 48 buffaloes) with histories of anestrous 60-90 days post-partum and belonging to different agroclimatic zones of Punjab were subjected to rectal palpation and blood samplings at least three times at weekly intervals. The body condition score (BCS) of each animal was also recorded. The animals were divided into two groups; viz., true anestrous (Gp-I) and subestrus (Gp-II) through rectal palpation of ovaries and plasma progesterone (P4) concentrations. Furthermore, the Gp I and II animals were divided into treatment (Gp Ia, 40 cattle and 16 buffaloes; Gp IIa, 12 cattle and 14 buffaloes) and control groups (Gp Ib, 20 cattle and 8 buffaloes; Gp IIb, 10 cattle and 10 buffaloes). True anestrous animals (Gp Ia) were treated with 3 injections of hydroxyprogesterone caproate (750 mg, i.m.) at 72-hr intervals followed by injection of equine chorionic gonadotropin (eCG; 750 I.U., i.m.) 72 hr after the last progesterone injection. The animals were bred at the first estrus after the induced one. The first service conception rate (FSCR), overall conception rate (OCR), services per conception and pregnancy rate of the true anestrous treated cattle (Gp Ia) were 44.4%, 48.0%, 2.08 and 60.0%, respectively. In the true anestrous control cattle (Gp Ib), only five that were observed to be in estrus failed to conceive. In the anestrous treated buffaloes (Gp Ia), the FSCR, OCR, services per conception and pregnancy rate were 50.0%, 62.5%, 1.6 and 62.5%, respectively. No buffalo amongst true anestrous control (Gp Ib) showed estrus. The subestrus animals (Gp IIa) were administered Prostaglandin F_2α (PGF_2α; 25 mg Dinoprost, i.m.) and bred at induced estrus. Amongst the Gp IIa animals, all cattle (100%) and twelve buffaloes (85.7%) responded to treatment. Of these animals, the FSCR and pregnancy rate at induced estrus in the cattle were 50.0% each, whereas they were 66.6% and 57.1%, respectively, in the buffaloes. The subestrus control animals (Gp IIb) remained infertile. In summary, the plasma P₄ profile can be used to differentiate true anestrous and subestrus animals and thus to determine a hormonal therapy. Furthermore, fertile estrus can be induced with hormonal therapy in anestrous and subestrus bovines.

View full abstract

In the present study, assay of the serum leptin concentration of the Japanese black bear (Ursus thibetanus japonicus) was attempted using a canine-leptin-specific sandwich enzyme-linked immunosorbent assay (ELISA). The dose-response curve of the bear serum was linear and parallel to the canine leptin standard curve. In mated and unmated bears, the serum leptin concentration was stable at low levels from May to August or September, gradually increased from September or October, and then remarkably increased in late November. We conclude that this method may be useful for measuring bear serum leptin concentration and that the serum leptin concentration changes annually with a peak in late November.

View full abstract

Canine parvovirus type 2 (CPV) is a pathogen that causes severe hemorrhagic gastroenteritis with a high fatality rate in pups worldwide. Since CPV emerged in the late 1970s, its origin has been explored with the conclusion that CPV originated from feline panleukopenia virus or a closely related virus. Both high mutation rate and recombination are assumed to be key factors in the evolution of parvoviruses. Here we provide evidence for natural recombination in CPV isolated from dogs in cell culture. Antigenic and genetic properties of isolates from 10 diseased pups were elucidated. Six pups had been vaccinated beforehand with live combined vaccine containing original antigenic type CPV (CPV-2). Six isolates recovered from 4 vaccinated pups in cell cultures were found to contain either CPV-2 or CPV-2-like viruses. The other isolates, including all those from non-vaccinated pups, were CPV-2b viruses. Antigenic typing of two CPV-2-like isolates, 03-029/M and 1887/f, with a monoclonal antibody panel suggested they were a mixture of CPV-2 and CPV-2a (03-029/M) and a recombinant of CPV-2 and CPV-2b (1887/f). Genetic analysis of the VP1 gene indicated that isolate 03-029/M was a mixture of CPV-2, CPV-2a and a recombinant of CPV-2 and CPV-2a viruses, while isolate 1887/f was composed of a recombinant of CPV-2 and CPV-2b viruses. This is the first demonstration of natural CPV recombination in the field and suggests that recombination in the evolution of CPV is a more frequent and important process than previously believed.

View full abstract

Feline infectious peritonitis virus (FIPV) is classified into serotype I and serotype II according to the amino acid sequence of its spike(S) protein. Antibody dependent enhancement (ADE) of macrophage infection occurs in the presence of antibodies to FIPV S protein, and a close relationship between ADE and neutralizing epitopes has been reported. The importance of differences in FIPV serotype on the induction of ADE remains unclear. In this study, we investigated whether the same or different serotype of FIPV induces ADE in cats. Specific pathogen-free cats were passively immunized with anti-type I or II FIPV antibodies, and we investigated the induction of ADE following subcutaneous inoculation with type I FIPV. Inoculation using FIPV serotype I enhanced the onset of FIP in cats passively immunized with FIPV serotype I-specific antibodies but not in those passively immunized with antibodies to FIPV serotype II. These data suggest that re-infection with the same serotype induces ADE in cats infected with FIPV.

View full abstract

Baculovirus-expressed foot-and-mouth disease virus (FMDV) nonstructural proteins 2C and 3D were used as the antigens in a western blotting assay. This assay allowed for differentiation of FMDV-infected pigs from vaccinated pigs. Serial studies were performed using sera collected from experimentally infected and vaccinated pigs. Positive reactions were found in the sera derived from the experimentally infected pigs. There was, however, no positive reaction in the vaccinated pigs. These results suggest that this western blotting assay is a useful method for differentiation of infected pigs from vaccinated pigs.

View full abstract

To determine whether or not mice are susceptible to hepatitis E virus (HEV) infection, C57BL/6 mice were experimentally infected with genotypes 1, 3 and 4 HEV by intravenous injection. Serum and stool samples were collected and used to detect HEV RNA and anti-HEV antibodies by RT-PCR and ELISA. The virus infection was monitored up to two months after inoculation; however, none of the serum or stool samples was positive for virus replication, demonstrating that C57BL/6 mice were not susceptible to HEV.

View full abstract

Hepatitis E virus (HEV) infection induces an acute hepatitis or a subclinical disease in humans. It is known that HEV is a zoonotic agent and pigs are major reservoirs of HEV. This study was conducted to determine the fecal shedding rates of HEV in various age groups of pigs and identify the genotypes of swine HEV prevailing in Korea. A total of 565 fecal samples were collected from suckling piglets, post-weaning pigs, growing pigs, and sows at 12 swine farms. RT-PCR was used to detect the presence of swine HEV in the feces. Every swine farm examined in this study had HEV-infected pigs. The fecal shedding rates of the swine HEV at individual farms were in the range of 2.1-35.4%. The overall fecal shedding rate of HEV in individual pigs was 17.5%. The HEV shedding rates of suckling piglets, post-weaning pigs, growing pigs and sows in their feces were 6.3, 16.3, 38.0 and 9.3%, respectively. When the genotypes of swine HEVs identified in this study were determined, they were all grouped into genotype 3. They were further subdivided into subtype 3a together with human and swine HEVs isolated in the U.S.A.

View full abstract

Equid herpesvirus 9 (EHV-9) was isolated from a herd of Thomson's gazelles affected by encephalitis. The natural host of EHV-9 is unknown, but zebras are suspected to be the source of infection in gazelles. To prove this hypothesis, we analyzed 43 sera from Burchell's zebras (Equus burchelli) and 21 Thomson's gazelles (Gazella thomsoni) from the Serengeti ecosystem for neutralizing antibodies. Seven zebra sera were positive for EHV-1, EHV-9 and EHV-1 from Grevy's zebra strains T965 and T616. The trigeminal ganglia of 17 other Burchell's zebras and one Thomson's gazelle were tested by EHV-9 gB and EHV-1 ICP0-specific nested polymerase chain reaction (PCR). PCR sequencing confirmed that one zebra ganglion was positive for EHV-9. These results suggest that the Burchell's zebras were exposed to EHV-9 and latently infected.

View full abstract

Cats harbor an infectious endogenous retrovirus, named RD114 virus. It is therefore necessary to monitor RD114 virus production in feline cells which are used for biological products as substrates. In this study, a feline sarcoma-positive leukemia-negative (S+L-) fibroblast cell line, named QN10S cells, was found to be highly susceptible to RD114 pseudotype viruses. The cells were transformed by infection with RD114 virus and the numbers of foci could be counted. The sensitivity of the focus assay was lower than that of the LacZ marker rescue assay in detecting RD114 virus. Although the assay is not suitable to detect a small amount of the virus, the assay will be useful for virological studies of RD114 virus.

View full abstract