Bovine leukocyte adhesion deficiency (BLAD) in Holstein cattle is an autosomal recessive congenital disease characterized by recurrent bacterial infections, delayed wound healing and stunted growth, and is also associated with persistent marked neutrophilia. The molecular basis of BLAD is a single point mutation (adenine to guanine) at position 383 of the CD18 gene, which caused an aspartic acid to glycine substitution at amino acid 128 (D128G) in the adhesion molecule CD18. Neutrophils from BLAD cattle have impaired expression of the β2 integrin (CD11a,b,c/CD18) of the leukocyte adhesion molecule. Abnormalities in a wide spectrum of adherence dependent functions of leukocytes have been fully characterized. Cattle affected with BLAD have severe ulcers on oral mucous membranes, severe periodontitis, loss of teeth, chronic pneumonia and recurrent or chronic diarrhea. Affected cattle die at an early age due to the infectious complications. Holstein bulls, including carrier sires that had a mutant BLAD gene in heterozygote were controlled from dairy cattle for a decade. The control of BLAD in Holstein cattle by publishing the genotypes and avoiding the mating between BLAD carriers was found to be successful. This paper provides an overview of the genetic disease BLAD with reference to the disease in Holstein cattle.
Lungs were obtained from five adult Baird's beaked whales (Berardius bairdii) and examined by means of light microscopy and scanning electron microscopy of corrosion casts. The alveolar septa of these whales are thick with a connective tissue core and a bi-layer capillary bed. A double capillary network is regularly found in the alveolar duct and alveolar septa. Occasionally, septa adjacent to alveoli and alveoli themselves show only a single capillary layer. The distance between the two capillary layers has a tendency to decrease toward the end of airspaces, suggesting an end result of capillary fusion. Vascular replicas of venous vessels have annular furrows at regular intervals of 50 to 100 μm, which are caused by focal aggregations of collagen fibers circularly oriented and located immediately underneath the endothelium. The first valves appear in the collecting venules gathering alveolar capillaries. These valves are quite characteristic of flap-, funnel-and/or chimney like structures.
In most mammals, the optic nerve fibers are myelinated in its extraocular part (EON) but not in its intraocular part (ION) and also in the retina. Transitional zone from the myelinated to unmyelinated optic nerve usually lies in the central part to the lamina cribrosa. It has been known that dogs contain exceptionally myelinated fibers in ION by light microscopy. The aim of this study was to investigate electron microscopically the retino-optic nerve junction in dogs and re-evaluate the barrier to migration of oligodendroblasts into ION. Fourteen adult dogs were used. EON was largely myelinated. In ION the percentage of myelinated fibers decreased gradually toward the retina. A narrow area of ION adjoining the retina was completely unmyelinated. In most mammalian optic nerves, oligodendrocytes are not found in ION. It has been suggested that oligodendroblasts are prevented from migrating from EON into ION; that is to say, there is a barrier to migration of oligodendroblasts. The lamina cribrosa, a dense meshwork of fibrous astrocytic processes, and a defect in the blood optic nerve barrier have been proposed as a candidate for the barrier to migration. Our results suggest, however, that these factors, at least in dogs, would be not involved in the formation of a barrier to migration of oligodendroblasts.
Differentiation of the histochemical characteristics of the olfactory receptor cells (ORC) was examined by immunohistochemistry for protein gene product 9.5 (PGP 9.5) and calretinin (CR) and lectin histochemistry for Phaseolus vulgaris agglutinin-L (PHA-L) in the developing olfactory epithelium (OE) of the barfin flounder. PGP 9.5 immunoreactivity was diffuse and CR immunoreactivity was restricted at day 7, but these immunoreactivities became intense in the OE toward day 91. Crypt cells were first identified at day 56. PHA-L staining was faint at day 28, but became intense toward day 91. These findings suggest that PGP 9.5-immunopositive cells, CR-immunopositive cells, crypt cells and PHA-L-reactive cells differentiate independently in the developing OE and constitute subsets of the ORC in the OE.
The pathogenicity of serotype 8 fowl adenovirus (FAV), isolated from gizzard erosions of slaughtered broiler chickens, was investigated. In experiment 1, 29 5-day-old specific-pathogen-free (SPF) chickens were inoculated with the isolates of serotype 8 FAV, M013 (group 1) or G0054 (group 2) strain, via an oral route. There were no clinical signs in any of chickens after inoculation, and mild gizzard erosions were observed macroscopically and microscopically in three inoculated chickens of group 2. FAV was recovered from gizzards and rectums but was not recovered from pancreas and livers from chickens in both inoculated groups. In experiment 2, 27 1-day-old SPF chickens were inoculated with the G0054 strain by intramuscular route. Five, 6, and 3 inoculated chickens died on days 3, 4, and 5 postinoculation (PI), respectively. Four, 3, 1, and 1 inoculated chickens became moribund with severe clinical signs such as ruffled feathers, severe depression and closed eyes from days 3 to 6 PI, respectively. Macroscopically, the common characteristic of the gross lesions of dead chickens and euthanized moribund chickens was discoloration of liver. FAV was recovered from the gizzard, liver, pancreas and rectum. Virus titers in the liver and pancreas were high until day 6 PI. Histologically, necrotizing hepatitis and pancreatitis with intranuclear inclusion bodies were observed in the inoculated chickens. These results indicate that some strains of serotype 8 FAV are able to reproduce not only gizzard erosion by oral inoculation but inclusion body hepatitis (IBH) by intramuscular inoculation.
An acute disease with high mortality occurred in the ostrich farm and characterized by depression, severe diarrhea and sternal recumbency. Four dead ostriches of the farm were submitted to the National Veterinary Research & Quarantine Service, and diagnosed as necrotic enteritis. In the gross and histopathological examination, extensive diffuse fibrinonecrotic enteritis was found in the small intestine, especially jejunum. Clostridium perfringens was isolated from a pure culture from the duodenum and jejunum of these birds. Based on our current knowledge, this is the first report of an outbreak of necrotic enteritis in the ostrich in Korea.
We developed a method to estimate the content of the toxic endotoxin in inactivated Salmonella vaccine in D-galactosamine-sensitized mice. Ten-fold serially diluted vaccines were injected intraperitoneally into D-galactosamine-sensitized mice. Lethality in the mice was judged 3 days after the injection. The best result was obtained when C3H/HeN mice were used for the test. Correlation was observed between the endotoxin content measured by Limulus amoebocyte lysate assay and the LD50 in the mouse safety test (r=0.81). These results suggested that this test could be applied to the estimation of endotoxin content in inactivated vaccines of Salmonella.
A 39 kDa protein of avian Pasteurella multocida strain P-1059 (serovar A:3) was purified from a crude capsular extract by immunoaffinity chromatography by using a ligand of purified mouse monoclonal antibody to the 39 kDa capsular protein of the strain. Protective activity of the purified 39 kDa protein antigen was determined by inoculation of ddY mice twice with 25 or 125 μg of the protein and challenge-exposure with 10 or 50 LD50 of strains P-1059 or X-73 (serovar A:1). The results showed that the antigen gave high protection (60 to 100%). These results indicated that the 39 kDa protein of avian P. multocida is a cross-protective antigen over serovars A:1 and A:3.
Despite a preeminent role of epidermal Langerhans cells (LC) in inducing primary immunity, application of gene-based modification to LC function is limited by lack of well-defined transcription regulatory units that can direct LC-specific gene expression. Previously we reported that the promoter activity of a 5'-flanking region of the dectin-2 gene (Dec2FR) is highly targeted to epidermal LC of transgenic mice bearing a Dec2FR-driven Luc gene. Using the mice, in which transcription activity of Dec2FR is measured by Luc assays, presently we characterized regulation of Dec2FR activity in leukocyte subpopulations under resting and activation status. Luc activity was highly variable in LC isolated from different skin areas and detected in other DC subset (dermal DC) but the levels were much lower than in resting LC. Activation of leukocytes markedly up-regulated Luc activity in all four subpopulations (CD11c+ splenic DC, Mac-1high peritoneal macrophages, splenic B220+ B cells, and CD3+ T cells). However, these levels remained lower than those in the resting and activated LC. These findings indicate that dectin-2 promoter activity remains targeted to epidermal LC even after activation of leukocytes, suggesting a high potential of Dec2FR to engineer LC-targeted gene expression to heighten efficacy of genetic vaccination and to manipulate phenotypes of preexisting immunity (Th1 vs. Th2).
An imbalance of excitatory and inhibitory transmitters in the brain has been suggested to cause epileptic seizures. In this study, we investigated the kinetics of glutamate (GLU) and γ-aminobutyric acid (GABA) in cerebrospinal fluid (CSF-GLU and CSF-GABA, respectively) using a high performance liquid chromatography (HPLC) in a canine model of complex partial status epilepticus (CPSE) induced by the microinjection of kainic acid (KA) into the unilateral amygdala. During the acute phase (3, 6, 12 and 48 hr after the onset of CPSE), CSF-GLU was significantly increased, while CSF-GABA was decreased, although not significantly. In the chronic phase, both CSF-GLU and CSF-GABA were significantly lower than normal at 72 hr after the onset of CPSE, and their levels returned to normal at 2 months. Results of the present study demonstrate that CSF-GLU is gradually increased in relation with seizure severity, and suggested the possibility that CSF-GABA was consistently decreased during CPSE induced by KA in dogs.
Scanning electron microscopy was carried out on 10 feline extracted permanent teeth from 3 cases with root resorption. Various-sized resorption lacunae were well defined, showing an etched pattern and configuration as shown in human deciduous teeth. In cats, regardless of the shape and depth of lacunae, the resorption lacunae showed opening dentinal tubules in the wall with or without cement matrix apperring only in the deep and round lacunae of human cases. Some specific process of mineralization for repairing dental root resorption was suggested in cats.
We examined overlapping genomic clones containing the chicken T cell receptor (TCR) Dβ-Jβ-Cβ complex, which contains a single diversity segment, four joining segments and four exons that encode the constant region. This sequence comprised 18.3 kb. All four Jβ sequences possessed typical recombination signal sequences (RSS) with intervening 12-bp spacers at their 5'-ends and splice sites at their 3'-ends. No Jβ-pseudogenes were identified. TGTG sequences in the RSS heptamer sequences were well conserved, as is the case in mammals. A chicken repeat 1-like sequence was found in the intron region between Jβ-1336 and Cβ, and several small repeat sequences were identified in intron regions throughout this cloned genome. As germline sequences revealed complete Jβ sequences, the CDR3 (complementarity-determining region) sequences of TCRβ from non-immunized splenocytes were analyzed. Non-coding (N) and palindromic (P) nucleotides were frequently observed at the Dβ-Jβ recombination sites. There were differences in length of deletion at the 5'-end of each Jβ. Deletion of the 5'-end of Jβ-1280 was particularly short when compared with that of Jβ-1336, but there were no changes in the length of the CDR3 using any of the four Jβ sequences.
The double-stranded RNA (dsRNA)-activated protein kinase (PKR), which is one of the products of interferon (IFN)-stimulated genes, participates in the biological actions of IFN such as antiviral effects and immune response. In the present study, we identified the primary structure of porcine PKR proteins by cDNA cloning. Porcine PKR protein consisted of 537 amino acids and had two dsRNA-binding domains similarly existing in PKR proteins of other species. The treatment with IFN-α induced the expression of PKR 3.9-fold in a porcine kidney cell line, LLC-PK1. The same results were obtained when the cells were treated with poly(I)·poly(C), but treatment with either IFN-γ or LPS did not induce this gene in LLC-PK1 cells. These results suggest similarity of the regulatory mechanisms in the PKR gene among mammalian species.
Anticoccidial efficacy of dietary fat was evaluated in calves with coccidial infection (Eimeria spp., including E. bovis and E. zuernii). Medium-chain triglycerides (MCT)-natural edible fats composed of caprylic (C8), capric (C10), and lauric (C12) acids - were given orally with milk to 5 calves and with 10% glucose solution to 3 older, weaned calves by using the reticular groove reflex. After 3 to 11 days of MCT feeding, all Eimeria spp. oocysts had disappeared from the feces of all calves. MCT had no adverse effects on appetite or on fecal pH, ammonia, lactic acid, or volatile fatty acid levels. MCT feeding for coccidial control in calves has minimal side-effects and has benefits in terms of residue-free food production.
The surface antigen P50 of Babesia gibsoni is an important candidate for the development of a diagnostic reagent for canine piroplasmosis. In order to establish an effective diagnostic method for practical use, the gene encoding truncated P50 (P50t) lacking a signal peptide and C-terminal hydrophobic regions were cloned and expressed in Escherichia coli as a fusion protein with glutathione S-transferase (GST). More than 90% portion of the GST-P50t was expressed as a soluble form, in contrast with GST-P50f (full-length), which was completely expressed as an insoluble form. This result indicates that removal of the hydrophobic signal peptide and C-terminus had dramatically improved its hydrophilicity. The purified GST-P50t was tested in an enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to B. gibsoni in dogs. The ELISA with GST-P50t clearly differentiated between B. gibsoni-infected dog sera and uninfected dog sera. In addition, the ELISA detected no cross-reactivity with sera from dogs experimentally infected with the closely related parasites, B. canis canis, B. canis vogeli, and B. canis rossi. Field serum samples collected from dogs in Japan and China were examined for the diagnosis of B. gibsoni infection by using the ELISA. 14.5% (9/62), 5.8% (7/120), and 5.4% (2/37) of tested samples were positive for dogs from Okinawa, Yamaguchi, and Osaka prefectures, Japan, respectively. On the other hand, 4.8% (2/41) of tested samples were positive for dogs from Nanjing, China. These results suggest that the GST-P50t could be a reliable reagent for practical use in ELISA for the serodiagnosis of canine piroplasmosis caused by B. gibsoni.
A spontaneous pleural mesothelioma was observed in a 4-year-old female woodchuck (Marmota monax). At necropsy, multifocal, tan to white, firm discrete nodules, 2 to 40mm in diameter, were scattered over the ventral parts of the lungs and their corresponding parts of the diaphragm and the thoracic wall. Histopathologically, the tumor cells were large, cuboidal-shaped and variable size, and were weakly positive with PAS and Alcian blue. Immunohistochemically, neoplastic cells were positive for both vimentin and cytokeratin, indicating mesothelial origin. This report represents, as far as we know, the first reported case of a spontaneous mesothelioma in woodchucks.
Hydroxyethyl starch (HES) is a nonpenetrating extracellular cryoprotectant. In contrast to glycerol, it does not require labor-intensive removal from thawed red blood cells (RBCs) prior to transfusion. In this study, we compared glycerol and HES, and assessed HES as a substitute for glycerol in cryopreserved canine RBCs. The RBCs were preserved for 2 months in liquid nitrogen using a 20% (w/v) glycerol solution, and variable concentrations of HES solution. We evaluated the two cryoprotectants by the percentage of post-thaw hemolysis from the total free hemoglobin, saline stability, osmotic fragility, and by observing the erythrocyte morphology using a scanning electron microscope after thawing. The optimal concentration of HES was 12.5% (w/v) for the cryopreservation of canine RBCs. The thaw hemolysis, saline stability, and osmotic fragility index were 25.6 ± 4.7%, 87.8 ± 6.9%, and 0.445 ± 0.024% NaCl respectively. These parameters resemble the results of RBCs frozen in a 20% (w/v) glycerol solution, which are 24.7 ± 5.2%, 99.2 ± 0.1%, and 0.485 ± 0.023% NaCl respectively. From a morphological point of view, 12.5% (w/v) HES showed the best cryoprotection of RBCs compared to the other concentrations of HES. These results suggest that HES could be a possible substitute for glycerol for the cryopreservation of canine RBCs.
Collagen synthesis was evaluated by measuring prolyl hydroxylase (PHL) activity induced within rat granulation tissue by a polyester non-woven fabric (NWF, 1 × 1 cm, 0.6 mm in thickness) impregnated with a chitin or chitosan suspension ranging in concentration from 0.1 to 10 mg/ml. In addition, PHL activity induced in rat granulation tissue by a NWF impregnated with a phosphate buffer solution was examined as a control. The PHL activity in each group remained low until 4 days post-implantation (Day 4). However, in the 10 mg chitin group, the PHL activity increased rapidly without scatter of the data at Day 7 and remained at a plateau until Day 14. In other groups, PHL activity increased linearly until Day 14. The data varied widely at Day 7. Compared to chitosan, chitin at the higher concentration was found to induce stable collagen synthesis in the early wound healing process.
We evaluated changes in hematology and chemical profile, and the tissue retention of hematoporphyrin derivative (HpD) following the intravenous injection in dogs. HpD at concentrations of 1, 5, 10, and 15 mg/kg was intravenously injected to 16 dogs (n=4 each) and complete blood count (CBC) and blood chemistry were performed on days 1, 3, 5, and 7 after the injection. To examine tissue retention, HpD (5 mg/kg) was administered to 15 dogs and 3 dogs were euthanized on days 1, 2, 7, 14, and 28 after the injection, respectively, to collect the skin, muscle, small intestine, spleen, kidney and liver as tissue samples. There were no significant changes in CBC and blood chemical profile except for an increase in LDH concentrations in dogs given 10 and 15 mg/kg of HpD at day 3. The levels of HpD retention in the tissues were ranked in the following order: liver > kidney > spleen > intestine > muscle > skin.
An 11-year-old, spayed female mixed-breed dog showed clinical signs of right forelimb lameness and pain by palpation around the neck. Radiography and computed tomography (CT) revealed an extradural mass at the 6th and 7th cervical vertebrae, which compressed the spinal cord. The mass was surgically removed and histopathologically diagnosed as schwannoma. The dog recovered her normal gait after hemilaminectomy and removal of the mass. Ten months after the surgery, the tumor recurred with absolute erythrocytosis and was surgically removed again. This removal temporarily resolved the erythrocytosis with a decrease in plasma erythropoietin (EPO) concentration. EPO protein was detected immunohistochemically in the tumor cells. Erythrocytosis in this dog may be caused by ectopic EPO produced in the schwannoma tissues.
Estrous synchronization using a Controlled Internal Drug Releasing device (CIDR) in combination with GnRH or estradiol benzoate (EB) treatment was investigated in Japanese black cows characterized with initial ovarian conditions. A total of 142 cows were allocated to one of four treatments: insertion of CIDR for eight days (Group A: n=34), CIDR with 100 μg of GnRH on d 0 (Group B: n=54, d 0=CIDR insertion), CIDR with GnRH on d 0 and 1 mg of EB on d 10 (Group C: n=20) or CIDR with 2 mg of EB on d 0 and 1 mg of EB on d 9 (Group D: n=34). All cows received 25 mg of PGF2α on d 7 and blood was collected for progesterone (P4) analysis on d 0, 8, and 21. AI was performed at estrus, but in Group D timed AI was set following a day of EB treatment. Estrus was induced in 141/142 cows, and the majority of which occurred on d 10 and 11 (98 cows, 34 cows). GnRH treatment induced more intermediate ovulation than EB treatment in cows with CL on d 0 (19.0% vs. 0%). Ovulation after CIDR removal was significantly higher in cows with CL on d 0 compared to those without CL (87.0% vs. 71.4%). Group B showed higher conception rates than those combined with Groups C and D where EB was injected after CIDR removal (51.1% vs. 38.9%). Conception had no correlation with either CL existence on d 0 or intermediate ovulation on d 8. P4 concentrations on d 8 were significantly lower compared to those on d 0 or d 21. On d 21 in cows without intermediate ovulation, Group A showed significantly lower P4 concentrations than the other 3 groups. The data suggests that CIDR insertion with PGF2α treatment is an effective method for estrous synchronization irrespective of initial ovarian conditions, and GnRH treatment at CIDR insertion induces intermediate ovulation and improves the conception rate in Japanese black cows.
This study was conducted to compare the developmental competence of somatic nuclear transfer (NT) embryos, after either ionomycin or ethanol activation, in locally bred goats. Donor cells were prepared from the ear skin fibroblasts of a female goat. Cells, at passage 3-8, starved by culturing in 0.5% FCS for 4-8 d, were used for NT. Immature oocytes were obtained from FSH-stimulated goats and matured for 22 hr before enucleation and NT. After fusion, the reconstructed embryos were activated with either ionomycin or ethanol followed by culturing in 6-dimethylaminopurine (6-DMAP) and cytochalasin B (CB), for 3 hr. In experiment I, the fused NT embryos (n=63, ionomycin and n=68, ethanol treatments, respectively) were cultured in B2 with a Vero co-culture system and their developmental competence was evaluated through to Day 9. In experiment II, the NT embryos at the 2-4 cell stage on Day 2 derived from each treatment (ionomycin n=46, and ethanol n=37), were transferred into 10 synchronous recipients. There were no significant differences between the NT embryos derived from the ionomycin and ethanol groups, in fusion (86.3% versus 82.9%), cleavage (90.5% versus 82.4%) and for morula/blastocyst development rates (9.5% versus 5.9%). Sixty percent (3/5) of the recipients from ionomycin became pregnant by midterm (2.5 mts) while only 20% (1/5) from ethanol treatment was pregnant by Day 45. The results demonstrate that activation with either ionomycin or ethanol in combination with 6-DMAP-CB treatment does not affect the development of cloned goat embryos.
We investigated fetal development and the estimation of fetal age of 127 Hokkaido sika deer fetuses, categorizing them into three groups according to the nutritional condition of populations. The order and time of the appearance of ossification centers were clarified, and fetal age was determined based on bone length and the appearance of ossification centers. Then we observed the differences in fetal growth among three populations, and discussed the effect of poor nutrition on the fetal growth. The results suggest that fetal diaphysial length of the femur was affected very little by nutritional conditions, whereas conception dates were delayed and fetal weight was restricted as the nutritional condition became poorer. Although it is impossible to know the exact accurate fetal age in wild populations, it was possible to create a standard to estimate fetal age more precisely by the method described in this study. Both the bone length and the appearance of ossification centers are reliable indices to estimate fetal age precisely in measurements available from fetuses of unknown age, and can be applied to estimate the fetal age of other populations of sika deer, whereas estimation of fetal age based on weight is prone to great errors.
The present study was conducted to establish an efficient production system for bovine transgenic somatic cell nuclear transfer (SCNT) embryos, the effect of various conditions of donor cells including cell type, size, and passage number on the developmental competence of transgenic SCNT embryos were examined with their expression rates of a marker gene. An expression plasmid for human prourokinase was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and a human prourokinase target gene into a pcDNA3 plasmid. Three types of bovine somatic cells including two adult cells (cumulus cells and ear fibroblasts) and fetal fibroblasts were prepared and transfected with the expression plasmid using a liposomal transfection reagent, Fugene6®, as a carrier. In Experiment 1, three types of bovine cells were transfected at passages 2 to 4, and then trypsinized and GFP-expressing cells were randomly selected and used for SCNT. Developmental competence and rates of GFP expression in bovine transgenic SCNT embryos reconstructed with cumulus cells were significantly higher than those from fetal and ear fibroblasts. In all cell types used, GFP expression rates of SCNT embryos gradually decreased with the progression of embryo development. In Experiment 2, the effect of passage number of cumulus cells in early (2 to 4) and late (8 to 12) passages was investigated. No significant differences in the development of transgenic SCNT embryos were observed, but significantly higher GFP expression was shown in blastocysts reconstructed with cumulus cells at early passage. In Experiment 3, different sizes of GFP-expressing transfected cumulus cells [large (>30 μm) or small cell (<30 μm)] at passages 2 to 4 were used for SCNT. A significant improvement in embryo development and GFP expression was observed when small cumulus cells were used for SCNT. Taken together, these results demonstrate that (1) adult somatic cells as well as fetal cells could serve as donor cells in transgenic SCNT embryo production and cumulus cells with small size at early passage were the optimal cell type, and (2) transgenic SCNT embryos derived from adult somatic cells have embryonic development potential.
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.
Hemagglutinin (H) gene of two CDV isolates, the Haku93 and Haku00 strains, from masked palm civets was molecularly analyzed. H genes of both two CDVs contained one open reading frame encoding 607 amino acids. Nucleotide and predicted amino acid sequences of H gene of the CDV Haku93 and Haku00 revealed high similarity to those of recent field isolates such as the Yanaka and Tanu96, while they showed limited identity to those of old vaccine strains. Potential N-linked glycosylation sites in both Haku93 and Haku00 were identical to other recent CDV isolates. Phylogenetic analysis revealed that the CDV strains derived from masked palm civets were classified into the group of recent Japanese CDV isolates.
Sero-prevalences of canine distemper virus (CDV), feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) were evaluated in 20 captive lions in two Japanese zoos. Anti-CDV antibody was detected in 13 of 20 lions. We could pursue antibody responses against CDV in three lions back to 1996. Sera collected in 1996 were negative for anti-CDV antibody, therefore, all of them showed sero-conversion in 2000. This result suggested that the epidemic of CDV infection in this zoo might have happened between 1996 and 2000. The lions were also examined for FIV and FeLV infections. We had no evidence for FeLV infection but eight lions were sero-positive for anti-FIV antibody.