Age-related morphological changes in the testis of the BDF₁ mouse were studied by light and transmission electron microscopy. No apparent changes were detected until 12 months of age. After 18 months of age, vacuoles firstly appeared in the somniferous epithelium. These vacuoles were gradually increased in number and showed a tendency to cluster with each other in accordance with age. While, germ cells were decreased in number. The sloughing of germ cells caused a thin seminiferous epithelium. In the tubule with a thin epithelium, spermatogenesis was severely interrupted. After 30 months of age, extremely thin seminiferous epithelia were observed. In these epithelia, most of spermatids and spermatocytes disappeared, and most of Sertoli cells lost their polarity to be flattened. On the other hand, in the interstitial region, PAS-positive cells (mononuclear phagocytes) tended to increase in number after 24 months of age. PAS-positive extracellular matrix newly appeared at 27 months of age. In the cytoplasm of Leydig cells, a whorl of sER was frequently found. Degeneration of testes proceeded with age. The regressive tubules occupied only 2.2% at 18 months of age, but extended to 63.0% at 33 months.

View full abstract

Mouse monoclonal antibodies (MAbs), Y-4b, F-6b and K-6a recognized as capsular antigens of A. pleuropneumoniae serotypes 1, 2 and 5, respectively, and MAb H-1b as lipopolysaccharide (LPS) of serotype 2 were produced. We examined the passive immunizing efficacy of these MAbs on A. pleuropneumoniae infection in C3H/HeJ mice. On the challenge infection of homologous serotype strains, they showed a sufficient protective effect in immunized mice. It was concluded that MAbs recognized as capsular antigen and LPS have a serotype-specific protective effect on A. pleuropneumoniae infection, suggesting the important role in preventing A. pleuropneumoniae infection.

View full abstract

Sedative and analgesic/anesthetic effects induced by a combination of medetomidine and midazolam were evaluated in pigs. This combination exerted a much more potent sedative effect than that induced by a medetomidine alone, even if the dose of medetomidine was reduced to one half, and even if the pigs were stimulated continuously during the induction phase. Pigs given this combination were induced to sedation smoothly and very quickly. During being sedated the arousal reaction induced by sensory stimuli were depressed profoundly and pigs could be placed in dorsal recumbency without any resistance. In addition, this combination produced moderate analgesic effect and apparent muscle relaxation. This potent effect induced by this combination seemed to be induced by a synergistic interaction between medetomidine and midazolam because the sedative effect achieved with this combination was much greater than that which could be expected from a simple additive response of both sedatives. This sedative combination may be a widely available and valuable for chemical restraint in pigs.

View full abstract

In this study, Recirculation Peritoneal Dialysis (RPD) apparatus using a pump to circulate the dialysate was devised and its dialysis efficiency was investigated. In the experiment, 15 mongrel dogs with body weights of 6.6±0.7 kg were used. The surgery to induce azotemia was performed on the dogs, a disk catheter for drainage was placed between the liver and diaphragm, and a straight catheter for infusion was placed on the abdominal side of the bladder. RPD was conducted using 2l of dialysate containing 1.3% glucose, and the dialysate was circulated by a pump through the peritoneal cavity and the dialysate chamber at the circulation rates of 30, 60, 90 and 120 ml/min. RPD was conducted for 3 hr and the clearances of urea nitrogen, creatinine, inorganic phosphorus and potassium were recorded every hour. The clearances in RPD became higher with an increase in the circulation rate. Although RPD requires two catheters in the peritoneal cavity, it has no appreciable technical difficulty in handling and is considered to be easier than hemodialysis. RPD enabled higher dialysis efficiency to be achieved in a short time compared with conventional peritoneal dialysis. It seems reasonable to conclude that RPD is a useful new dialysis technique for animals.

View full abstract

Swine interleukin 2 (IL-2) activity was assayed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) colorimetric assay using murine IL-2 dependent cell line (CTLL-2). The culture supernatant of mesenteric lymph node (MLN) cells stimulated with phytohemagglutinin-P (PHA) induced a generation of MTT formazan in a dose-dependent manner, suggesting dose-dependent proliferation of CTLL-2. The maximal swine IL-2 activity was observed in the culture of MLN cells at 1 to 2×10⁷ cells/ml when stimulated with 20 to 40 μg/ml PHA for 48 hr. Based on these findings, a large culture of MLN cells to prepare swine IL-2 were performed under the following condition; cell concentration of 1×10⁷ cells/ml, PHA concentration of 20 μg/ml, a culture scale of 200. to 400 ml, and a stirring speed of 30 rpm. Swine IL-2 activity was detected from 4 hr after PHA stimulation, and rapidly increased until 16 hr. Almost maximal IL-2 activity in stirring culture was observed at the incubation of 20 hr. Swine IL-2 was partially purified by Sephacryl S-200 gel filtration and the estimated molecular weight was about 32 kD based on the peak of IL-2 activity. The pI value of swine IL-2 was estimated to be approximately pH 5.3. Swine IL-2 was sensitive to acid (pH 3.2) or alkaline (pH 10.5), 4 or 8 M urea, trypsin, and the heating at 70°C. These physico-chemical properties of swine IL-2 was similar to those of human, murine or feline IL-2.

View full abstract

Digoxigenin-dUTP-labeled DNA probe was prepared from a cDNA clone complementary to the gene encoding S1 region of the spike protein of infectious bronchitis coronavirus (IBV) strain M41. The probe exclusively reacted with four strains at 56°C which were grouped to the same serotype as the strain used for the probe. In contrast, at 68°C, the probe reacted only with the homologous strain and did not react even with the strains belonging to the same serotype. The dot-blot hybridization thus appeared serotype-specific at 56°C and strain-specific at 68°C. In addition, it was revealed that the S1 gene has some nucleotide sequence variation even among strains in the same serotype. This technique should be applied to determining serotypes of the virus isolates and to differentiating field isolates from the vaccine strain.

View full abstract

Analyses on the effects of polymeric N-acetyl-D-glucosamine (chitin), which was obtained from squid pen, on histogenic activation in dogs were carried out with subcutaneous implants (5×5 cm²) of polyester non-woven fabric (NWF) supplemented with chitin (chitin group) and NWF (control group). These materials were implanted at 4 sites, on the lumbodorsal and lumbosacral subcutaneous tissues on both sides of the midline in each dog under general anesthesia. The implants and their surrounding tissues were isolated on post-implantation days (PIDs) 2, 4, 8, and 18 under general anesthesia. In the chitin group, the implant was organized gradually and its organization was completed on PID 18, when obvious angiogenesis toward the NWF was observed. On the other hand, in the control group, obvious angiogenesis toward the NWF was not observed macroscopically. Numbers of mononuclear (MN) and polymorphonuclear (PMN) cells concentrated around the implants on PID₂ were larger in the chitin than control group. In the chitin group, formation of granulating tissue around the implant was indicated on PID 4, whereas such a phenomenon was not observed in the control group. From these results, chitin accelerates the migration of MN and PMN cells to the NWF site with rapid follow-up organization of the NWF accompanied by angiogenesis.

View full abstract

The sponge-, cotton-, and flake-type remedies made of chitin (chitin-sponge, chitin-cotton, and chitin-flake, respectively), and non-woven fabric of polyester (NWF) composited with chitin (chitin-NWF) were applied to various types of trauma, abscess, surgical tissue defect and herniorrhaphy in 147 clinical cases including 72 dogs, 38 cows, 33 cats, 2 rabbits, one monkey and one horse. Chitin-sponge was applied in 30 cases as filling agent of surgical tissue defect, and in 25 cases of trauma, 31 cases of abscess as wound dressing or tissue defect filling agent. In 77 out of 86 cases (89.5%), good healing developed. When chitin-sponge was buried in surgical tissue defects due to oncotomy in 20 cases, recurrence of the tumor developed in one case on one month post-operatively, but was not recognized for 3-24 months in 19 cases. Chitin-NWF was applied in 2 cases of trauma and 12 cases of abscess as wound dressing or tissue defect filling agent, 6 cases as filling agent of surgical tissue defect, and 12 cases of umbilical hernia as prosthesis of suture site of hernia ring. In 28 out of 32 cases (87.5%), good healing developed. Chitin-cotton was applied in 8 cases of trauma and 12 cases of abscess as wound dressing or tissue defect filling agent. In 18 out of 20 cases (90.0%), good healing developed. Chitin-flake was applied 9 cases of trauma as wound dressing or tissue defect filling agent. In 8 out of 9 cases (88.9%), good healing developed. In all cases, no side effects were observed.

View full abstract

Two-step polymerase chain reaction (nested PCR) method was examined for the diagnosis of scrub typhus. Primers were derived from the type-specific antigen (TSA) gene DNA sequences of Rickettsia tsutsugamushi, Gilliam strain. These primers served to produce rickettsia-specific products in the amplification of template DNA prepared from all serovariants, Gilliam, Karp, Kato, Kawasaki, Kuroki and Shimokoshi strains, and the fragments of product after digestion with several kinds of restriction endonuclease showed the respective patterns to strain in acrylamide or agarose gel electrophoresis. The rickettsia-specific DNAs were also derived, by this nested PCR, by amplifying DNA from patients' bloods and mites from endemic areas, and the serotype of rickettsiae infected to these hosts could be identified from fragment patterns of the amplified products observed after endonuclease treatment. These results indicate that this PCR is sensitive and specific method not only for detection of rickettsial DNA in patient specimens and in mites, but also for the typing of rickettsiae infected to these hosts.

View full abstract

Parasitological, histopathological and immunohistochemical examinations were carried out on three slaughtered cattle with many nodules in all the striated muscles. At necropsy, many yellowish green rice-grain sized nodules including cheesy contents were observed in all the striated muscles. Histopathologically the nodules were granuloma principally consisting of eosinophiles. No Sarcocystis cysts nor bradyzoites were found in the nodules, but intact sarcocysts were found in the normal tissues surrounding the nodules. The central necrotic focus of nodules showed intense positive responses against anti-Sarcocystis cruzi rabbit serum by immunohistochemical examination. From the above findings the slaughtered cattle were diagnosed as chronic sarcocystiasis.

View full abstract

A single dose (1 mg/kg) of milbemycin D was administered orally to 24 dogs with microfilaremia of Dirofilaria immitis, and the number of circulating microfilariae was counted weekly. The number was decreased by 3 to 8% of the pretreatment levels 1 week after the drug administration. The number remained relatively stable for the first 8 weeks and was gradually increased thereafter without returning to the pretreatment levels by 20 weeks. Three or 4 dogs each were euthanatized on day 1, and 1, 4, 8, 12, 16 and 20 weeks after the drug administration to examine the effects of the drug on intrauterine microfilariae and embryos of the worms. Although no intrauterine microfilariae were destroyed directly by the drug, degeneration and collapse of morular embryos and decrease in the number of intrauterine microfilariae were observed 12 after weeks the drug administration. These findings became more remarkable with time, and no intrauterine microfilariae developed in any worms by 20 weeks. The electron-microscopic findings revealed that the nucleoli of oocytes had a high density in the worms of 1, 4 and 8 week groups. Unequal size of cleavage cells and decrease of polysome number were noticed in the early-stage embryos after 8 weeks. It was assumed that the drug might have some effect on the chromosomes or genes in the germinal stem-cell of the heartworm and interfere with protein syntheses, resulting in inhibition of embryonic development. Twelve dogs were given milbemycin D (1 mg/kg) a total of 4 or 6 times monthly according to a prophylactic program. Circulating microfilariae disappeared after 1 to 5 treatments, and none of them were confirmed at the beginning of the next mosquito season. Milbemycin D was considered to inhibit the development of heartworm embryos and to induce occult heartworm infection.

View full abstract

A sensitive and highly specific enzyme-linked Immunosorbent assay (ELISA) system for detection of bovine coronavirus was developed using monoclonal antibodies, which showed both neutralization and hemagglutination inhibition activities. A monoclonal antibody was coated onto microplates for capturing antigen and a mixture of two monoclonal antibodies served as detecting antibodies. Using this assay, 40 of 202 fecal specimens from 29 herds were shown to be positive for viral antigen. From 10 ELISA positive specimens from 5 herds, the virus was isolated after several passages on human rectal adenocarcinoma (HRT-18) cell culture.

View full abstract

Tumor celled from 15 canine lymphoma/leukemia cases were examined for genetic rearrangements of immunoglobulin and T-cell receptor (TCR) genes in parallel with cell surface antigens. Ten of these 15 cases showed rearrangements of the immunoglobulin heavy chain (IgH) gene, while 4 cases displayed TCRβ-chain gene rearrangements on Southern blot analysis. All the cases with IgH gene rearrangements had multicentric form lymphoma, and 6 of the 10 cases were cell surface immunoglobulin-positive. On the other hand, the cases with TCR gene rearrangements included atypical lymphoma/leukemia cases, and 3 of the 4 cases were Thy-1 antigen-positive. Although the tumor call lineage of a considerable number of lymphoma/leukemia cases could not be determined by phenotypic analysis, examination of the IgH and TCR gene rearrangements disclosed the lineages of 14 of 15 cases. Genetic analysis demonstrated that the tumor cells in most canine multicentric lymphomas were formed by clonal expansion of B-lymphocyte. These findings show that studies on the rearrangements of immunoglobulin and TCR genes are very useful for understanding the cellular origin, clonality and hierarchy of canine lymphoma/leukemia cells.

View full abstract

Sixty-six dogs suffering from intervertebral disk diseases on cervical and/or thoracolumbar disks were treated by a ventral fenestration. The breeds affected with disk diseases were Dachshund (65.1%), Beagle (15.2%), Shih Tsu (4.5%), Pekingese (4.5%), and others (18.2%). Sites suffered from disk diseases and received disk fenestration most frequently were from T10-11 to L2-3. However, other disks were also needed the operation in some cases. An average number of disks received fenestration was 6.0. Days to walk after the fenestration in 51 cases varied 1 to 120 days (average: 14.9±22.0 days, X^^-±S.D.) depending on their severity. The recovery rates from the follow-up study were as follows: In grade I (3 cases, able to walk with back pain) and grade II (14 cases, slight ataxia and paresis) it was 100%, respectively. The rates in grade III (23 cases, paraplegia with positive deep pain) and grade IV (26 cases, paraplegia with lack of deep pain) were 73.9% and 65.4%, respectively. A few recurrence after the operation were observed in this study. As a result, the ventral fenestration was extremely effective as a treatment for disk diseases in the dog.

View full abstract

Lower apparent concentrations of ferritin were observed in horse plasma than in serum using the enzyme-linked immunosorbent assay (ELISA). However, the ferritin concentrations in plasma and serum were increased to the same level on heating the samples at 75°C for 15 min. These results suggest that horse plasma has specific ferritin-binding protein(s) which inhibit(s) the ferritin assay. The apparent ferritin concentrations in horse serum were markedly decreased by adding horse fibrinogen to the serum. It was also found that fibrinogen bound to spleen ferritin and inhibited the immunoassay of this protein. From these results, it was concluded that horse fibrinogen is one of the ferritin-binding proteins which inhibit the immunoassay of horse ferritin.

View full abstract

Antagonistic effects of atipamezole (80, 160 and 240μg/kg, im), and flumazenil (100μg/kg, iv) or atipamezole (80μg/kg) and flumazenil (100μg/kg) on medetomidine-midazolam induced sedation were evaluated in laboratory pigs. Atipamezole at each dose effectively reversed sedation, and the arousal time, standing time and total recovery time were significantly shortened. The optimal action of atipamezole was seen at a dose of 160μg/kg. At this dose recovery from the sedation was quick and smooth, and adverse effects such as hyperactivity or tachycardia were minimal. Flumazenil reversed sedation temporary, but the pigs went back to moderate sedation soon after arousal. The combination of atipamezole and flumazenil most effectively reversed the sedation, however atipamezole (160μg/kg) alone was thought to be practically potent enough to antagonize sedation induced by medetomidine-midazolam in laboratory pigs.

View full abstract

The effect of 2-carboxythylgerumanium sesquioxide (Ge-132) as an interferon-gamma (IFN-γ) inducer on post-surgical immunosuppression was evaluated from the immunological response augmented in canine neutrophils, macrophages and peripheral blood lymphocytes (PBL) using the chemiluminescence technique. Experimental gastrotomy was performed on dogs in two groups; one group was subjected to sham-surgery without any medication, and the other was treated by Ge-132 administration at 24 hr before operation. Although the phagocytic activities of neutrophils, macrophages and PBL in the sham-operated group were depressed transiently after surgery, those in the Ge-132-administered group (Ge-132 group) were enhanced for a long time after surgery. It appeared that the generated free radical, which blocked the phagocytosis of macrophages and PBL, was activated by IFN-γ. These results suggest that Ge-132 pre-treatment may be efficacious and useful in preventing the multifaceted clinical symptoms induced by post-operative immunosuppression in dogs.

View full abstract

Alterations of the p53 tumor suppresser gene have been observed in a variety of human and mouse tumors. For investigation of the role of this gene in tumors in cats, feline p53 cDNA was molecularly cloned by PCR amplifications using primers based on the sequences conserved among several species. The cloned cDNA appeared to cover approximately 90% of the open reading frame of the feline p53 gene and had characteristic structures in common with the p53 genes of several other species. The amino acid sequence similarities of the feline p53 with the human, mouse, rat and chicken counterparts were 82.9%, 75.6%, 76.5% and 57.2% respectively. Moreover, using a panel of feline x rodent somatic cell hybrids, the feline p53 gene was assigned to feline chromosome E1. These data will be useful for determining the role of the p53 tumor suppresser gene in feline tumors.

View full abstract

To demonstrate the prevalence of Toxocara eggs in sandpits in Tokushima Prefecture, Japan, sand samples were examined. Of 46 sandpits surveyed, 29 sandpits (63.3%) had Toxocara eggs. Sandpits in public parks and playgrounds in residential areas were more contaminated (87.5%) with the eggs than those in kindergartens, schools, and children's centers (36.4%). To examine the seasonal change in the contamination, sand samples obtained from five sandpits were examined monthly from May 1990 to April 1991. Toxocara eggs were found in the majority of sandpits (3/5-5/5) in the spring, early summer, and autumn. In the summer and winter, the rates of sandpits contaminated were lower (2/5-3/5) than in other seasons. Egg counts became smaller in the summer and winter, especially in summer. The ratio of T. canis to T. cati eggs recovered was 2:3. Fecal examination of 144 puppies revealed that 98 (68.0%) were positive for T. canis eggs. These findings show that Toxocara eggs, a possible causative agent of visceral larva migrans, commonly present in sandpits of the urgent area. To prevent the contamination of sandpits with these eggs, control measures are needed.

View full abstract

Using the appA gene encoding Actinobacillus pleuropneumoniae-RTX-toxin II (ApxII) as a probe, Southern hybridization demonstrated the presence of appA sequence in all 12 serotypes except serotype 10. Serotype 10 strains had a genetic locus with low homology to appA (tentatively designated Lha). DNA sequence analysis revealed that Lha contained a part of hlyIA gene encoding a 105-kDa hemolysin ApxI. Southern hybridization demonstrated the presence of Lha (hlyIA) sequence not only in serotype 10 but also in serotypes 1, 5a, 5b, 9, and 11, which had strong hemolytic activity with sheep red blood cells and were highly virulent for mice. These results suggest that ApxI may be associated with the virulence phenotype of the organism.

View full abstract

The reticular fibers of the capillary sheath and splenic cord were studied in the pig spleen by transmission electron microscopy to reveal their components and the presence of sialic acid in the amorphous ground substance. Collagen fibrils, elastic fibers, microfibrils, nerve fibers and smooth muscle cells were observed in the reticular fibers of the splenic cord, while only microfibrils were recognized in the reticular fibers of the capillary sheath. The binding of LFA lectin to the splenic cord was stronger than the capillary sheath. These findings may suggest that the reticular fibers of the splenic cord include numerous functional elements and perform an important role during contraction or dilation of the spleen. On the other hand, it seems to be reasonable to term the capillary sheath as "capillary basement membranous reticular tissue", since the reticular fiber of the capillary sheath resembles the basement membrane of the capillary in its components.

View full abstract

An 11-month-old castrated male Japanese domestic cat was euthanized because of neurological symptoms such as shivering and difficulty of walking. Histopathological examination showed glial proliferation and marked deposition of ceroid-lipofuscin in the neuronal and glial cells of the brain. Ceroid-lipofuscin was deposited also in reticuloendothelial cells of the liver, spleen and some lymph nodes.

View full abstract

The authors studied some reproductive characteristics of wild female sika deer (Cervus nippon yesoensis Heude, 1884) in Ashoro District, Hokkaido. Large numbers of females attained sexual maturation at the age of yearling, and the pregnancy rate of yearlings and older was 96.4% (n=28). These high levels of fertility should be considered the standard for high quality populations of sika deer. The estrus cycle began in late October. Twinning was exceptional. Sex ratio of fetuses was statistically 1:1, and there was no significant difference in fetal weights between males and females in March. The birth weight is estimated to be around 6 kg. Accessory corpora lutea were found in 77.8% (n=27) of pregnant females.

View full abstract

Morphological characteristics of the early developmental stages of Theileria sergenti in the vector tick were observed by light and electron-microscopies and compared with those of other Theileria species. Just before the repletion of nymphs, various stages of the parasite were observed in gut contents of tick by light microscopy: the spherical intra-erythrocytic stage, the ring-form stage, the spindle-shaped stage and the round-form stage. Electron microscopy revealed that the spherical intra-erythrocytic stages were 1-2 μm in diameter and were marginally located in host erythrocytes. The organisms liberated from host erythrocytes into the tick gut lumen had a large nucleus, an endoplasmic reticulum, electron dense-organelles and a double-walled, mitochondrion-like organelle. In addition ticks had ray-bodies in the gut lumen. These bodies had short protrusions containing 1-3 microtubules and a labyrinthine structure containing highly electron-dense organelles, so they were considered as the developing microgamont of T. sergenti.

View full abstract

A Ca²⁺-dependent phosphorylcholine (PC)-binding protein in normal chicken serum was purified by affinity chromatography on p-aminophenyl PC-Sepharose 4B followed by gel filtration on Sephacryl S-300. In gel filtration, the isolated PC-binding protein was eluted in a symmetrical protein peak at the position of approximately 100, 000. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the protein was resolved into two protein bands of 31, 000 and 38, 000 under nonreducing conditions and of 40, 000 and 46, 000 under reducing conditions. These results suggest that chicken serum PC-binding protein may be composed of two different subunits which contain in intrachain disulfide bonds.

View full abstract

Carnitine [4, -(N, N, N-trimethyl-ammonio)-3-hydroxybutanoate] was added to the diet to study its effect on lipid concentrations in liver and serum of rats. In rats administered with a high-fat diet containing 30% corn oil, simultaneous administration of carnitine reduced the concentrations of triglycerides and total cholesterol in both liver and serum. The addition of carnitine to a high-cholesterol diet decreased the levels of cholesterol and lipids in serum, but the cholesterol level to remain higher than control level. The present findings suggested that addition of carnitine may improve the lipid metabolism in obesity.

View full abstract

Invagination or transformation of a zygote of Theileria sergenti into a kinete was examined with Giemsa-stained smears of the midgut of vector ticks, Haemaphysalis longicornis and H. mageshimaensis. Zygotes invaginated almost simultaneously with the moulting of host ticks. They were round and oval, and measured 5.4 to 6.7 μm in diameter on average. The kinetes developing in the zygotes were situated in the periphery of cytoplasm and were spindle- or club-shaped.

View full abstract

F344 Rat hepatocytes (HCs) that had been exposed to ultraviolet (UV) light were transplanted into the dorsal subcutaneous tissues of Balb/c mice. Four days after the transplantation, the anti-HC delayed-type hypersensitivity (DTH) response was assessed by determining the response to a direct challenge with non-irradiated HCs. The DTH response in mice transplanted with 600J/m2-UVB-irradiated HCs was suppressed significantly compared with that with non-irradiated HCs. Furthermore, the DTH responses evoked by challenge with non-irradiated HCs were similar to those evoked by UV-irradiated HCs.

View full abstract

The structure of the sheathed artery and the number of branches of the sheathed capillary were investigated by three-dimensional reconstruction computer graphics in the pig spleen. The capillary branched 1 to 6 times in the capillary sheath in more than 90% of all samples examined. The sheathed artery varied in shape and size in accordance with the number of branches and direction of the capillary. The usual descriptions for the sheathed artery were suggested to be mostly in appropriate at least for that of the pig spleen.

View full abstract

A hemagglutination-inhibition (HI) test was applied to distinguish virulent Aujeszky's disease virus infected pigs from those immunized with a glycoprotein gIII deletion vaccine. The vaccine strain, dlg92/dltk, did not have hemagglutination activity with mouse erythrocytes and the pigs vaccinated five times with the dlg92/dltk strain failed to develop HI antibody, although they developed neutralizing antibody with 128 to 512 titers to Aujeszky's disease virus. On the other hand, these pigs produced HI antibody 1 to 2 weeks after virulent virus inoculation. Thus the animals infected with virulent strain were easily differentiated from the animals immunized with the gIII deletion vaccine.

View full abstract

A feline large granular lymphocyte (LGL) cell line was established from a cat with an alimentary-form lymphoma. This cell line, designated as FGL, had many large azurophilic granules in the cytoplasm, which were typical to LGL cells. Proviral genome of feline leukemia virus was detected in the chromosomal DNA of FGL cells, and reverse transcriptase activity was also demonstrated in the culture supernatant. Furthermore, we found expression of interleukin 2 (IL-2) receptor α-chain on the cell surface of FGL and its natural killer activity against human erythroblastic leukemia cell line, K562.

View full abstract

We experienced vertical infections of puppies with Hepatozoon canis from 1990 to 1992. In 23 of 29(79.3%) puppies from a total of 6 deliveries, gamonts or meronts were detected from 16 to 60 days after birth. The mother dogs were delivered of the puppies under tick-free conditions treated with an acaricide. There was no chance of infection of the puppies with H. canis after birth. Therefore, the vertical transmission of H. canis was supposed to be established in the family of dog.

View full abstract

Nodular hepatic lesions caused by larval Echinococcus multilocularis were found in a four-year-old female thoroughbred race horse born and raised in Hokkaido. Before detection of the infection, the infected animal was transported around Honshu for racing. The present disclosure of hydatidosis in a race horse raises concern over the potential danger of spreading the infection throughout Japan by horses possibly infected in Hokkaido.

View full abstract

The cattle with adequate α-tocopherol (Vit E) and marginally deficient selenium (Se) status manifested significantly lower anti-Haemophilus somnus antibody titer than the cattle supplemented with Se in the later stage of an 8-week trial. However, in the early stage no difference was observed in magnitude of anti-H. somnus antibody development between them. These results suggested that Se may contribute to anti-H. somnus antibody production, and that Vit E can make up for Se deficiency to a certain degree.

View full abstract

Choroid plexus carcinoma was diagnosed in a 10-year-old maltese dog with chief complaint of progressive ataxia and head tin. No abnormalites was observed on hemogram, radiographs of the skull, and electroencepharograph (EEG). Neurological examination suggested central vestibular lesions. On the magnetic resonance imaging (MRI) examination, images after contrast enhancement with Gadolinium DTPA-dimeglumine showed a rough circular lesion with an increased signal intensity in caudal fossa. This lesion was histopathologically confirmed to be choroid plexus carcinoma.

View full abstract

We investigated the appearance of gamonts in peripheral leukocytes of 13 Hepatozoon canis infected dogs from June 1990 to December 1992. In almost all the dogs, the numbers of gamonts increased from spring to autumn, and decreased from autumn to winter. Particularly in the dogs used for hare hunting, a large number of gamonts was detected from spring to autumn. This finding reveals that the gamont increases in number in the dog which ingested the infected ticks during the hunting season.

View full abstract

Infective larvae, larvae in the lung and adult-stage worms in the small intestine of Strongyloides venezuelensis were analysed for protein by two-dimensional gel electrophoresis. The infective larvae were differentiated from the other two stages of parasite with 13 stage-specific spots, whereas the larvae in the lung and the adult-stage worms were identical to each other in spot patterns except for 6 spots.

View full abstract

An examination of an antibody to reticuloendotheliosis virus (REV) in sera of chickens and other avian species collected from various districts in Japan was carried out. Agar gel immunodiffusion test (AGID) to the chicken sera revealed positive results in 25.9% of the 54 farms, 21.4% of the 126 flocks and 14.3% of the 1, 892 individual chickens. All the AGID positive sera also were positive in indirect immunofluorescence and/or virus neutralization tests. In avian species other than chickens, Peking ducks (1/120; 0.4%) and pheasants (4/27; 14.8%) were AGID test positive. This is the first study conducted in Japan.

View full abstract

Early-stage pig embryos were collected from superovulated donor gilts (60-72 hr post hCG injection) and co-cultured in modified Brinster medium for ovum culture (mBMOC-2) + porcine oviduct epithelial cells (POEC) or in the amniotic fluid of a developing chick embryo (CEAm). The development rate to the compacted morulae or blastocyst stage was significantly higher (P<0.01) in embryos co-cultured in CEAm (60.0%) than those co-cultured in mBMOC-2 + POEC (18.0%). The results indicate that CEAm could be used for production of compacted morulae or blastocysts from early-stage pig embryos. This culture system could also be valuable in situations where a CO₂ controlled incubator is not available.

View full abstract

Haptoglobin (Hp) concentrations were evaluated in 42 cow sera at around parturition by single radial immunodiffusion using anti-cow Hp rabbit serum. At parturition, Hp was detected in 31 of 42 cows. The detection rate (74%) was significantly higher than those before (0-10%) and after parturition (5-21%). At parturition, serum concentrations of cortisol and non-esterified fatty acids were significantly higher than those before and after parturition. A significantly lower concentration of serum triglycerides at parturition, compared to the values before parturition, was also observed. From these results, Hp is considered to be associated with fatty liver development of cows, because fatty liver particularly occurs in the peripartum period.

View full abstract

The localization of lymphocytes in the lymphoid organs of cyclophosphamide (Cy) treated chickens and untreated control chickens was compared immunohistochemically using a variety of monoclonal antibodies (CT3, 2-6, 11-39, TCR1, TCR2, TCR3, L22, 11G2, 3E8, B-4D-4, A-13). In the Harderian glands of Cy treated chickens, an increase of T cells was observed, though T cells were a few in untreated controls. These increased T cells consisted of CD4 positive or CD8 positive cells. Further, these T cells were stained with TCR2 or TCR3 antibody, and a small number of cells were stained with TCR1 antibody. In other lymphoid organs such as the bursa of Fabricius, thymus, spleen and cecal tonsils, B lymphocytes severely decreased or disappeared in Cy treated chickens, though no significant alteration in T cell distribution was observed.

View full abstract

The effect of oral administration of an active egg white product (AEWP) on neutrophil function in weanling piglets was investigated. The peripheral blood neutrophils of piglets receiving single doses of 20 mg/kg and 100 mg/kg displayed increased phagocytic activity for latex particles from 1 day after administration. This increased phagocytic activity persisted for 5 days in the 100 mg/kg group. Piglets receiving a dose of 30 mg/kg/day for a week displayed increased neutrophil phagocytic activity throughout the administration period. Moreover, when the administration of AEWP was resumed 10 days after withdrawal, neutrophil phagocytic activity rapidly increased again. Thus, AEWP enhanced the nonspecific phagocytic activity of neutrophils when given to piglets by the oral route.

View full abstract