Cardiac output (CO) measurements by the three methods of dye dilution, pulsed Doppler echocardiography and thermodilution in horses under anesthetized conditions were compared. Although CO determined by the thermodilution method was slightly higher than those obtained by the other two methods, the measurements by all methods showed almost similar results. The coefficients of correlation between the dye dilution and thermodilution methods, the dye dilution and pulsed Doppler echocardiography methods, and the thermodilution and pulsed Doppler echocardiography methods were 0.87, 0.89, and 0.88, respectively (P<0.01). These results indicate that pulsed Doppler echocardiography and thermodilution methods could be no less useful than the traditional dye dilution method for evaluating of CO in horses. The pulsed Doppler echocardiography method may offer some advantage over other two methods; it is non-invasive and enables continuous measurement of CO.

View full abstract

An immunohistochemical micromethod for quantification of fast-myosin in frozen histologic sections of rat skeletal muscles was developed. The principle of this method was enzyme-linked immunosorbent assay (ELISA). We used frozen tissue sections as models of the antigen-coated wells of ELISA plate. The intensity of immunoreactivity of the frozen section to an anti-fast-myosin monoclonal antibody was quantified directly from the color developed with the second antibody coupled with peroxidase using phenol-4-aminoantipyrine as a substrate. Then, the same section was incubated in 0.01 M acetic acid solution to cleave antigen-antibody complexes, followed by colorimetric measurement to obtain the absolute value of total protein per section. Fast-myosin content in the frozen tissue section was expressed as mg of fast-myosin per g of total protein. In this micromethod, the minimum area and the optimum thickness of the section were 5 mm² and 10μm, respectively. Fast-myosin contents in the extensor digitorum longus and soleus muscles were 185.0±6.1 and 17.5±2.4 mg/g, respectively. The results obtained by this micromethod were in good agreement with those obtained by two conventional methods, immunohistochemical morphometry and biochemical determination. This micromethod is useful for a quantitative evaluation of the contractile function of the mammalian skeletal muscles.

View full abstract

Sensitized peripheral blood lymphocytes (PBL) obtained from canine transmissible venereal sarcoma (CTVS)-regressed dogs were more cytotoxic against CTVS cells than non-sensitized PBL from untreated dogs. Cytotoxicity shown by sensitized PBL was inhibited significantly by the addition of anti-major histocompatibility complex (MHC) class II mouse monoclonal antibody as well as that of anti-dog thymocyte rabbit serum. The degree of cytotoxic activity shown by lymphokine activated killer (LAK) cells induced from non-sensitized or sensitized PBL was similar to that of the activity shown by sensitized PBL. These LAK activities were also prohibited by the addition of anti-dog thymocyte rabbit serum. Immunohistochemical examination demonstrated that MHC class II antigens were expressed on the surface membrane of CTVS cells and thymocyte antigens were detected on the surface of the tumor infiltrating lymphocytes. From the results mentioned above, lymphocytes which play a central role in tumor regression are considered to be T cells. These cells might recognize MHC class II antigens on the surface membrane of CTVS cells in tumor regression.

View full abstract

An assay procedure for ornithine carbamoyl transferase (OCT), which is known to be a liver-specific enzyme, was modified to be adaptable to bovine serum. The concentration of carbamoyl phosphate and the pH of the reaction reagent solution shifted to 60 mM and 7.2, respectively. These modifications contributed to the augmentation of assay sensitivity. The day-to-day reproducibility was 7.9% (coefficient variation) for serum with high OCT activity and 14.8% for normal bovine serum. The activity was stable for 3-4 months by the storage at -20°C and at least 6 months at -80°C. The OCT activity and other biochemical components including aspartate aminotransferase and gamma glutamyl transpeptidase were measured in sera from 164 dairy or raising cows reared at 7 farms. The normal level of OCT activity in sera from these cows ranged from 9.2 to 25.1 U/l (mean±2SD). By comparison between the farms, the highest mean value of OCT activity was found in a farm where cows were suspected to have some kind of latent liver disease from the data of other biochemical parameters. We conclude that the OCT activity is a very useful diagnostic indicator of liver disease in cattle.

View full abstract

Epizootiological studies of hantavirus infection among urban rats were carried out through the surveys repeated 11 times at the same dumping ground area in 1983 to 1988. A total of 279 rats (Rattus norvegicus) were captured during the surveys. Sero-positive animals to hantavirus strain SR-11 were detected in all the surveys. Overall positive rate of rats 6 months old or more (94/128, 73.4%) was significantly higher than that of younger rats (23/151, 15.2%, x²=96.4, P<0.001). Therefore, age dependent acquisition of hantavirus infection among rats was confirmed. Seven hantavirus strains, KI-83-262 (August, in 1983, designated as strain KI-262 in our previous report (2)), KI-85-1 and 85-2 (July in 1985), KI-88-4, 88-11, 88-15 and 88-24 (October, 1988) were isolated from lung tissues of adult rats which have high titers of neutralizing antibody. Although the serum specimens of virus carrier rats neutralized the infectivity of all the KI isolates, no apparent antigenic change in the isolates was detected by indirect immunofluorescent antibody (IFA) assay using polyclonal and monoclonal antibodies (MAbs) regardless of isolation years. However, neutralization test showed slight difference of antigenicity among KI strains. These results epizootiologically confirmed that hantavirus infected persistently among urban rats in a presence of neutralizing antibody.

View full abstract

The ultrastructure of the Shiba goat Sertoli cell was observed using light and transmission electron microscopy. In the basal portion of the Sertoli cell, the nucleus was located near the basement membrane and was irregular in outline. A number of filaments with intermediate width were observed around the nucleus. A multivesicular nuclear body, composed of numerous vesicles of different sizes and ribosome-like structures, was detected within the nucleus. The majority of cell organelles was situated in this basal portion of the cytoplasm. Oval mitochondria were randomly distributed. A well-developed laminated smooth endoplasmic reticulum (sER) was frequently found within the cytoplasm of Sertoli cell. Lysosomes and large lipid droplets were also recognized. While, the outline of the basal lamina was almost straight. No nodular processes were observed in the lamina. The Golgi complex appeared only in the supranuclear region. In the middle and apical portions of the Sertoli cell, elongated mitochondria and microtubules were oriented parallel to the long axis of the cell. The laminated sER was also detected in these portions. The apical head of slightly-elongated spermatids was occasionally surrounded by the laminated sER. The head of maturing spermatids without laminated sER revealed a bleb-like shape. The microfilament bundles at the ectoplasmic specialization site were regularly arranged. Judging from the present observations, we havd suggested that only the multivesicular nuclear body and the laminated sER may be the peculiar structures which are commonly found in the Sertoli cell of ruminants.

View full abstract

Intermittent positive pressure ventilation (IPPV) is useful method for compensate of respiratory function in anesthetized horses. However, IPPV may decrease cardiac output. Alterations in cardiac output of three groups (N=5) healthy, halothane-anesthetized mares were determined and compared during a 120 min period of anesthesia. The groups were as follows: spontaneous ventilation (SV), controlled ventilation using an end-inspiratory pressure of 20 cmH₂O (CV20) and a third group using 25 cmH₂O (CV25) inspiratory pressure. In the CV groups, respiratory function was adequately maintained. Although, cardiac output tended to decrease over time in each group. After 105 min of anesthesia in the CV groups, the cardiac outputs decreased below 50 percent of pre-anesthetic values. In the CV25 group, cardiac outputs were significant difference (p<0.05) from the SV group after 45, 90 and 120 min of anesthesia. There was no significant difference in cardiac output between SV and CV20 group over time. These values suggest that when long durations of anesthesia was used with the IPPV, decrease of cardiac output should be improved. In clinical use of halothane anesthesia, an end-respiratory pressure of 20 cmH₂O seems to be appropriate because the mild decrease in cardiac output was observed even though a little high PaCO₂.

View full abstract

Histamine receptors on bovine peripheral blood lymphocytes (PBL) were detected by three different methods: a rosetting technique, binding to histamine-bearing Sepharose beads and immunofluorescence staining. The rosetting technique used histamine-rabbit serum albumin (H-RSA) conjugated to bovine red blood cells to detect histamine receptors and this showed that 10.8% of bovine PBL were positive. A method using H-RSA conjugate coupled Sepharose beads also detected histamine receptor bearing PBL but was not quantitative. The indirect immunofluorescence method, by which the subpopulation of histamine receptor bearing lymphocytes can be easily double stained to concurrently identify the B cell marker, revealed that PBL, the B cell and T cell fraction of bovine PBL contained 18.4, 52.8 and 9.3% histamine receptor bearing cells, respectively. This method was found to be more stable and more easily quantifiable than the other two methods. Blocking tests using the histamine H1 receptor antagonist diphenhydramine and the histamine H2 receptor antagonist cimetidine suggested that bovine PBL have both H1 and H2 receptors on their surfaces. Addition of histamine into cultures of PBL at the concentration range 10^-6 to 10^-3 M suppressed the response of PBL to the mitogen phytohemagglutinin. The histamine induced suppression of mitogenesis could be reduced partially by the H2 receptor antagonist cimetidine, but not by the H1 antagonist diphenhydramine . It is possible that histamine induced suppression of PBL mitogenesis was mediated by H2 receptors on T cells.

View full abstract

Two monoclonal antibodies (MAbs) were established in 20 clones of MAbs generated against cytokeratin fraction extracted from canine squamous cell carcinoma to investigate the expression of intermediate filament proteins during tumorigenesis. These MAbs were confirmed to react with purified cytokeratin by ELISA. One monoclonal antibody, MAb32 reacted all layers of epidermis except the cornified layer and mammary myoepithelial cells but not any epithelial cells. Another antibody named MAb24 exclusively reacted the basal monolayer of epidermis, the stratum germinativum. Any positive reactions with MAb24 were not detected in normal mammary gland. From the analysis by two-dimensional gel electrophoresis followed by immunoblotting, it was revealed that MAb24-recognizing cytokeratin subunit gave a molecular weight of 57 kilodalton and a isoelectric-pH value of pI 5.1, indicating type I (acidic) cytokeratin. In intraductal papillomas developed in canine mammary glands, most tumor cells were positively stained with MAb32 in addition of myoepithelial cells while no positive reaction with MAb24 was seen. In ductal carcinomas, MAb24-positive cytokeratin was begun to express by tumor cells with positive reaction of MAb32 where these cells showed infiltrative growth into the stroma. We therefore proposed that 57 kilodalton-type I cytokeratin was a molecular marker for malignant transformation in canine mammary tumor and these antibodies could be useful tools to investigate the change of cytokeratin expression during tumorigenesis.

View full abstract

The foot-pad test was performed to reveal the induction of delayed-type hypersensitivity (DTH) to Fusobacterium necrophorum in mice experimentally infected with F. necrophorum. For the foot-pad test, heat-killed cells of F. necrophorum were found to be better than viable bacteria as eliciting antigens. The thickness of foot-pad could be measured properly at 48 hr after administration to the foot-pad of heat-killed bacteria. An intraperitoneal dose of the order of 10⁵ or 10⁶ of viable bacteria evoked a similar foot-pad response. Peak responses were found on days 4 and 14 after the sensitization. The response was found to be specific. This response could be transferred by spleen cells to genetically homogeneous mice, but not to genetically heterogeneous mice. Serum could not transfer the response to either heterogeneous or homogeneous mice. Thus, these results indicate that DTH could be induced by F. necrophorum.

View full abstract

The permeability of mammary gland capillaries to ferritin was investigated by transmission electron microscopy. In virgin mice, the concentration of tracers in perivascular spaces increased with the advance of time after injection. The ferritin never passed through the intercellular junction of the endothelial cells. In the early to middle stages of lactation, numerous ferritin particles were observed in the basal cytoplasm of alveolar epithelial cells after only 1 min of circulation. These findings indicate that a large amount of materials quickly pass through the capillary walls during these periods for milk production. The number of vesicles labelled with ferritin per μm² of endothelial cytoplasm decreased remarkably in the late stage of lactation. This result suggests that the permeability of vesicles declines along with the degeneration of alveolar cells.

View full abstract

To analyze longitudinal distribution of pulmonary vascular resistance, we proposed a five element lumped model which partitioned pulmonary circulation into pulmonary arterial, middle and pulmonary venous segment. The validity and anatomical correlation of the model were tested in an isolated, perfused, canine lung lobe preparation with inflow/outflow occlusion techniques. With arterial occlusion, pulmonary arterial pressure fell rapidly and then exponentially. With venous occlusion, pulmonary venous pressure rose suddenly and then exponentially. Theoretical pressure profiles produced by computer simulation of the model well approximated the general characteristics of the experimental traces. Serotonin increased the pressure gradient across the pulmonary arterial segment (delta Pa), whereas histamine increased the gradient across the pulmonary venous segment (delta Pv). Neither drug altered the gradient across the middle segment (delta Pm). The results suggest that the lumped model is a useful concept to understand the longitudinal distribution of pulmonary vascular resistance, and that delta Pa, delta Pm and delta Pv reflect the resistance distribution of anatomical pulmonary arteries, alveolar vessels and pulmonary veins, respectively.

View full abstract

A total of 116 strains of Mycobacterium avium-intracellulare complex were isolated from swine with tuberculous lesions at meat inspection, during 1982-1983. Of them, one strain isolated from the lesion in the mesenteric lymph nodes was identified as M. avium serovar 1 (swine strain). The pathogenicity of the swine strain in chickens was compared with that of a reference strain (M. avium serovar 1). Chickens were inoculated intravenously with each strain (2×10⁶ colony forming units: CFU) and they were autopsied at 30 days after inoculation. Enlargement of the liver, spleen and kidney was observed in the inoculated chickens. In histopathological examination, many glanulomatous lesions were observed in the lung, liver and spleen. Infiltration of lymphocytes was found in the kidney and pancreas. Both inoculated organisms were recovered from the liver (10³-10⁶ CFU/g) and spleen (10³-10⁵ CFU/g) of each inoculated chicken. The reference strain (<3.0×10² CFU/g, ml) was also recovered from the lung, kidney, pancreas and the bile of the inoculated chickens. All the isolates were identified as serovar 1. It was shown that the swine strain had pathogenicity in chickens comparable to that of the reference strain.

View full abstract

Rabbits were fed with two kinds of atherogenic diet, one containing 0.5% cholesterol and 3% soybean oil and the other 0.5% cholesterol and 6% peanut oil, for three months to compare the atherogenic property of the diets. The soybean oil diet seemed to be superior to the peanut oil diet for evaluation of the anti-atherogenic effect of drugs, because the former caused milder vascular lesions than the latter. Using this rabbit model for atherosclerosis, the anti-atherogenic effect of clentiazem, a new calcium antagonist, was examined. Clentiazem at an oral dose of 30 mg/kg/day significantly reduced the size of atheromatous lesion in the aortic arch and thoracic aorta, and lowered the collagen content of the aortic intima and media, although it did not decrease serum lipid levels. On the other hand, clentiazem showed no clear effect on reducing the coronary atherosclerotic lesions. These results suggest that clentiazem may inhibit the progression of diet-induced aortic atherosclerosis without normalizing the serum lipid levels.

View full abstract

Cardiovascular responses and radiographic image quality during cerebral angiography, aortofemoral angiography and left ventriculography with nonionic ioxilan, iohexol or iopamidol were compared with those of ionic sodium meglumine diatrizoate in pentobarbital anesthetized dogs. Injection of all contrast media caused cardiovascular changes to a greater or lesser degree, e.g., hypotension, bradycardia, tachycardia, a decrease in left ventricular pressure (LVP) and its first derivative (dP/dt), and prolongation of the P-Q and Q-T intervals. Ionic diatrizoate had a greater effect on cardiovascular parameters than nonionic contrast media during angiography in all areas. Moreover, diatrizoate produced cardiac arrhythmias and prominent changes in blood rheology concerned with blood viscosity and deformability of the erythrocyte. The cause of various effects of contrast media seemed to lie mainly in osmolality, viscosity and partially ionic additives. The radiographic image quality of all of the contrast media used was similar, but nonionic ioxilan and iohexol with lower iodine content and low osmolality gave better radio opacity than ionic diatrizoate in cerebral angiography. These results suggested that nonionic contrast media should be recommended as a diagnostic tool for both animals and human patients in poor health.

View full abstract

Specific monoclonal antibodies (MoAbs) to Actinobacillus pleuropneumoniae (APP) serotypes 1 and 2 which recognized serotype-specific antigens were produced. It was revealed that the two serotype-specific MoAbs H1-18 and H22-7 recognized O polysaccharides of the lipopolysaccharide (LPS) from APP serotypes 1 and 2, respectively, in the results of antigen analysis by means of SDS-PAGE and Western blotting. Furthermore, ddY mice immunized passively with the above type-specific MoAbs were protected against challenge infection by the homologous serotype of APP at 24 or 48 hr later. However, H1-9 and H3-2 MoAbs recognizing serotype-common protein antigens of APP did not show signs of any protective effect. These results showed that LPS from APP bacterial cells was one of the structural substances in the serotype-specific antigens, and an important component as one of the antigens protecting against the homologous serotype strain.

View full abstract

To measure interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-like activities in canine serum, bioassays were conducted using human melanoma A375S1, IL-6 dependent murine hybridoma MH60.BSF2, and WEHI 164 murine sarcoma subclone 28-4. Clinically normal adult beagles were experimentally induced endotoxic shock by an intravenous injection of lipopolysaccharide or local inflammation by an intramuscular injection of turpentine oil. IL-1-like activity was detected in sera from dogs with endotoxic shock. IL-6 and TNF-like activities were detected in sera from both dogs with endotoxic shock and local inflammation. IL-1-like activity in sera from the dogs with endotoxic shock declined after dilution with either medium or serum obtained before treatment (pre-serum), but the IL-1-like activity was maintained to a greater extent in samples diluted with pre-serum compared to those diluted with medium. TNF-like activity declined equally after dilution with either medium or pre-serum. On the other hand, IL-6-like activity was inhibited at low dilution. It was, therefore, necessary to dilute the serum samples to 1:180 from dogs with endotoxic shock or 1:60 from dogs with local inflammation, in order to minimize the effect of inhibitory factors on IL-6-like activity. IL-6-like activity was neutralized by monoclonal antibody against murine IL-6 receptors. TNF-like activity was neutralized by anti-mouse TNFα rabbit serum. However IL-1-like activity was not neutralized by either anti-mouse or anti-human IL-1 rabbit serum.

View full abstract

The catalytic reaction of renin, an aspartyl proteinase, with angiotensinogen is the rate-limiting step of the renin-angiotensin system involved in the maintenance of blood pressure and electrolyte balance in mammals. We have characterized species-specific expression of the hepatic renin gene by RNase protection experiment, primer extension analysis, and promoter assay using an in vitro DNA transfection. RNase protection experiments revealed that the renin gene is expressed in rat liver, but neither in mouse nor in human. Primer extension analysis identified the putative promoter region of the rat renin gene, which contains TATAAAA sequence, a canonical regulatory DNA element. In order to test whether the upstream region of the renin gene with respect to the putative transcription initiation site is a functional promoter, we have examined the ability of the 5'-flanking sequences of the rat renin gene as well as the human and mouse genes to activate expression of a reporter gene containing the bacterial chloramphenicol acetyltransferase (CAT)-coding sequences, by transient transfection assays. In transfected HepG2 cells, a hepatoma cell line, only the rat renin promoter was capable of driving the CAT gene expression. These results suggested that the rat-specific renin gene expression in the liver could be primarily determined by its promoter specificity.

View full abstract

Effect of bioceramic implantation on the intermandibular space along with plating in rostral mandibulectomy was investigated in the dog. In this group, bioceramic beads consisting of a complex of hydroxyapatite and tricalcium phosphate were implanted in the intermandibular space between the lingual surfaces of the fracture ends. In two other groups, the dogs received only plating on the ostectomized end, or they received only rostal mandibulectomy without plating. No difficulty in mastication was observed in the implanted group after surgery. In the dogs which received plating, however, difficulty was noted only in the 4th week when wet food was replaced by dry food, and in the control group in the 6th week after the surgery. From the radiological and microscopical findings, in dogs with only plating or without the fixation there was no bony union in the intermandibular space at 16 weeks, though the increase in fibrous tissue and bony callus in the area was much greater in the plated dogs than in the control group. In the implanted group, on the other hand, the increase in callus formation was considerable compared to the other groups. Moreover, the lingual surfaces of the fracture ends were well ossitied at 12 postoperative weeks. This suggests that in canine bilateral rostral mandibulectomy the stabilization of the fracture ends with plates and bioceramic implants filling a gap in the intermandibular space may enhance the ossification between the fracture ends and prevent postoperative difficulty in mastication.

View full abstract

To study the relationship between a bovine serum mannan-binding protein (MBP) and a serum protein reactive with a Ra chemotype strain of Salmonella sorovar Typhimurium (Ra-reactive factor, RaRF), both proteins were isolated by use of their affinity for yeast mannan and the Salmonella cells followed by affinity chromatography on mannobiose-Sepharose 4B. Both purified proteins showed a major protein band with a molecular weight of 33, 000 and a few faint bands in sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis under reducing conditions. In Western blotting with rabbit anti-bovine MBP antibody, the major subunit of both proteins were found to be immunologically identical. Similar findings were also obtained with purified human MBP and RaRF. From these findings, bovine and human serurn MBP are suggested to be electrophoretically and immunologically the same as their corresponding RaRF.

View full abstract

We describe a technique for isolation and primary culture of bovine hepatocytes, and their metabolic characterization. Hepatocytes were isolated from the caudate lobe of bovine liver by perfusion with 0.25 mM ethyleneglycol tetraacetic acid and 0.05% collagenase. The viability and yield of the cells were 70-92% and 0.1-3.6×10⁷ cells/g liver, respectively. When the isolated hepatocytes were cultured in Williams' medium E, they began to spread in 3 hr and formed monolayers in 24 hr. These monolayers were retained for at least 6 days. To monitor the metabolic activities specific to liver, synthesis and secretion of albumin were measured by labeling with [³⁵S]-methionine and immunoprecipitation. This activity was low in isolated hepatocytes, but increased after culturing 1-3 days, and decreased again after 6 days. Glycogenolytic activity was also assessed by measuring glucose release to the medium by stimulation with epinephrine. The glycogenolytic response to epinephrine was also enhanced by culturing the hepatocytes 1-3 days, but was decreased after 6 days. Since the isolated bovine hepatocytes retained the liver-specific activities of albumin synthesis and glycogenolysis for several days in culture, these cells are useful for cellular and molecular studies on the functions of bovine liver.

View full abstract

The aim of these studies was to investigate the effect of body posture on circulatory and respiratory system function in unmedicated cattle. The plasma cortisol concentration was also measured and served as an indication of the level of stress imposed by animal handling and positional manipulation. Six mature, healthy Holstein cows were physically restrained and studied in standing, supine and right lateral postures. The plasma cortisol concentration increased with the change in body position. In a supine position, the value was increased to more than three times the control value (p<0.001). The arterial oxygen tension and oxygen saturation were significantly decreased (p<0.001) with changes in body position. The decrease was most pronounced when cattle were restrained in a supine position. Arterial carbon dioxide tension, heart rate, mean arterial pressure and central venous pressure did not change significantly with changes in body posture. Restraining of cattle in a lateral recumbent or supine position without introducing anesthesia was found to exert a strong stress which affected the respiratory function and increased the plasma cortisol level.

View full abstract

Typical Pneumocystis carinii pneumonia was found in a male thoroughbred foal (46 days old) suffering from diarrhea and hypogammaglobulinemia after birth. The characteristics of the organisms were demonstrated by Grocott methenamine silver staining, and scanning and transmission electron microscopy. The present foal had no histological lesions suggesting immunodeficiency. However, he could not get adequate colostrum from his dam, because she died of hemorrhagic shock due to immuno-mediated thrombocytopenia at delivery. This condition was considered to have predisposed the foal to the pneumonia.

View full abstract

The distribution of T. canis larvae and pathological changes of the liver caused by them were studied in chickens inoculated orally with 1, 500 embryonated eggs during 1 and 50 days after inoculation. The number of larvae recovered varied from 40 to 192 in the liver, 8 to 166 in the muscles, 0 to 4 in the heart, 0 to 2 in the spleen, 0 to 1 in the brain, respectively. Small white foci were observed on the surface of the liver since 6 days after inoculation. Histopathological examination of the liver revealed infiltrations of leukocytes and acidophilic cells, thickening of blood vessel and bile duct wall, and granulomatous nodules. The pathological changes become more remarkable in the later stage of inoculation.

View full abstract

A Ca²⁺-dependent agarose-binding protein was purified from chicken serum by affinity chromatography on SeaKem agarose gels followed by gel filtration on Sephacryl S-300. Purified protein was eluted in a symmetrical peak at the position of molecular weight of 146, 000. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, it was resolved into a single protein band with a molecular weight of 39, 000 under nonreducing and of 41, 000 under reducing conditions. Thus, the agarose-binding protein is suggested to be composed of noncovalently-associated identical subunits which contain intrachain disulfide bonds.

View full abstract

An immunohistochemical micromethod for quantitation of type I collagen in frozen histological section of rat kidney was developed. A principle of this method is enzyme-linked immunosorbent assay (ELISA). The intensity of immunoreactivity of the section to an anti-type I collagen antibody was quantitated, and then the total protein content in the same section was measured colorimetrically. Type I collagen content was expressed as mg of type I collagen per g of total protein. In this micromethod, the minimum area and optimum thickness of the section were 5 mm² and 10μm, respectively. Type I collagen content in the rat kidney section was 3.02±0.12 mg/g. This method should be useful for diagnosis of renal failure.

View full abstract

A 19-month-old Holstein female manifested muco-hemorrhagic diarrhea. At necropsy, the colon contained a large amount of bloody material mixed with mucus and there was diffuse petechial hemorrhage on the mucosal surface. Histologic and electron microscopic examination of the colon revealed the characteristic lesion of attaching and effacing Escherichia coli (AEEC) infection. The organisms were associated with mucosal lesions and stained positively by an immunoperoxidase technique using antiserum to E. coli O group 15. Diarrhea caused by AEEC was recognized in this adult cow.

View full abstract

Unilateral anophthalmia in a Holstein calf was examined morphologically. On the left side, a small cystic remnant of the eye ball (CRE) was present in the orbit. The CRE was adhered to the dura mater through an abnormal foramen formed in the orbital region of the cranial base. At this region of the left cerebral hemisphere, a porencephalic change was detected. Histologically, the pigment epithelium was continued from the lining of the inner surface of CRE to the residual cerebrocortical tissue attached to the dura mater. These characteristic changes seem to suggest the partial fusion of the outer layer of the optic cup to the telencephalon during optic organogenesis.

View full abstract

Odontogenic neoplasm was found in the mandibular incisor area of a 3-year-old Japanese black ox. Macroscopically, the cut surface was white and firm with streaks of hard tissue. Histologically, the tumor was composed of enamel organ structures with odontogenic hard tissue in fibromatous areas. It was diagnosed as ameloblastic fibro-odontoma. The absence of the 4th permanent incisor confirmed by radiography and microscopic examination strongly suggests that this tumor has been originated from the tooth germ tissues of the permanent left 4th incisor.

View full abstract

In cell suspensions of suprachiasmatic nucleus harvested every 3 hr from rats kept under 12 hr: 12 hr light-dark cycle and constant darkness, we have detected a Mr 64-kDa protein whose synthesis exhibits two distinct daily peaks in SDS-PAGE. Analysis of densitometer tracings revealed that the synthesis of other proteins was independent of the time of day or not reproducible. Maximum synthesis of the 64-kDa polypeptide occurred at around CT6 and CT21, which are almost coincident with the phase advance regions of circadian activity rhythm induced by anisomycin and light pulses [15], respectively. These results suggest that the 64-kDa protein in SDS-PAGE may be a part of the circadian clock mechanism.

View full abstract

Out of 2, 138 pregnant Japanese serows (Capricornis crispus), one case of the maceration of fetus was found in the winter of 1991, and examined pathologically. Because the fetus was covered with the hairs in the head and the neck regions, the fetus seemed to be implanted in the last breeding season and retained. The endometrium lacked the placentomes completely and showed metaplasia to the keratinized or non-keratinized squamous epithelium. In the non-keratinized region, the accumulation of neutrophils, eosinophils, lymphocytes, plasma cells and foreign giant cells was prominent in the subepithelial connective tissue.

View full abstract

A histological study was made on the omasum of sheep, cows, sika deer, and Japanese serows in order to confirm the existence of the submucosal nerve cell bodies in the omasal laminae. In the present study, seventeen submucosal nerve cell bodies were found in seven sections from four out of twenty-two sheep.

View full abstract

A 2.5-year-old female Thoroughbred horse was referred to the veterinary teaching hospital for right front limb lameness of 1 year duration. Physical examination and diagnostic nerve blocks failed to localize the origin of the lameness. Scintigraphy with ^99mTc-MDP suggested increased radionuclide uptake in the palmar metacarpal soft tissues of the right front limb. Ultrasonographic examination revealed hypoechoic lesions in the superficial digital flexor tendon and the suspensory ligament, suggesting tendinitis and desmitis. Combined imaging modalities improved detection and characterization of the cause of a long-standing obscure lameness.

View full abstract

Studies were conducted to determine if the amniotic fluid of a developing chick embryo (CEAm) could be used as a co-culture system for the maturation of pig oocytes. In Exp. 1, the pig oocytes were cultured in mTCM-199 (control) or day 3, 4 and 5 CEAm. The maturation rate of pig oocytes in the control vs CEAm was significantly higher (P<0.001). The maturation rate of pig oocytes cultured in day 3 vs day 4 and 5 CEAm was significantly higher (P<0.001). In Exp. 2, the pig oocytes were cultured in day 3 CEAm maintained either in a conventional incubator with 40-70% relative humidity or incubator with 5% CO₂ in air atmosphere at 37°C or 39°C. A significantly lower maturation rate (P<0.001) was obtained when CEAm were maintained in an incubator with 5% CO₂ gas atmosphere regardless of the temperature. In Exp. 3, pig oocytes cultured in day 3 CEAm and mTCM-199 (control) were fertilized in vitro (IVF). The penetration and male pronucleus (MPN) formation of pig oocytes cultured in day 3 CEAm was significantly lower (P<0.01) than those cultured in mTCM-199 medium. The results presented here demonstrate that CEAm could be used to induce maturation of pig oocytes, however its efficacy is influenced by factors such as developmental stages of chick embryos, temperature and gas atmosphere.

View full abstract

Human c-yes-1-related canine proto-oncogene in genomic DNAs from 21 clinically normal dogs was analyzed by Southern blot hybridization. The present study indicated that this proto-oncogene was well conserved in clinically normal dogs, however, there were structural changes in some dogs. These changes were different in each individuals and detected in low frequency.

View full abstract

Water consumption was measured in 199 suckling pigs aged 1 to 28 days. The suckling pigs began to drink water 3 to 5 hr after birth. Water consumption per pig increased from 36 ml/day at the age of 1 day to 403 ml/day at the age of 28 days. Water consumption per kg body weight, on the other hand, remained constant at 51 to 62 ml, regardless of age. This results indicates that it may be possible to add drugs to drinking water for the purpose of medication in suckling pigs.

View full abstract

Gross and microscopic changes at the injection site in pigs and cats were investigated for 8 weeks after an intramuscular injection of oil adjuvant ISA-70 emulsion, containing inactivated Newcastle disease virus antigen. In pigs, an egg-sized and discolored lesion with pinpoint to miliary-sized nodules was observed at 2 to 8 weeks post injection (PI). In cats, there was partial thickening of the subcutaneous tissue at 2 to 8 weeks PI. Histopathologic changes in pigs were fundamentally similar to those in cats, however, the local tissue reactions in pigs were severer and more protracted than those in cats. The lesions in pigs were characterized by formation of large-sized cysts and well-developed encapsulation of the cysts with epithelioid cells.

View full abstract

The usefulness of blood sampling paper for the detection of antibodies against porcine cytomegalovirus (PCMV) by enzyme-linked immunosorbent assay (ELISA) was examined. The PCMV antibody titer of whole blood collected on the paper agreed with that of serum and the absorbances of the corresponding samples were well correlated (r=0.88). Blood was collected from 26 piglets in the field on the blood sampling paper and ELISA was performed. The maternal PCMV antibody of these piglets decreased during the 8 weeks after birth and IgM antibody against PCMV was detected in four piglets.

View full abstract

Polymorphisms of the p53 tumor-suppressor gene and its related sequences were investigated among inbred rat strains. In a series of Southern blot hybridizations using the human p53 cDNA probe with various restriction endonucleases, HindIII digests and PstI digests showed interstrain variation in the length of hybridizing fragments. Distribution of the HindIII variant fragments among 17 inbred rat strains was identical with that of PstI variant fragments. The variant fragments were segregated as codominant alleles in backcross progeny, and the locus for this restriction fragment length polymorphism of the p53-related sequence was found to correspond to a p53-related sequence located on rat chromosome 9.

View full abstract

A 9-year-old male horse showed emaciation, weakness and trembling and was euthanatized. Histopathological examinations revealed loss, swelling and chromatolysis of motor neurons throughout the spinal ventral horns, axonal degeneration of the ventral spinal roots. Eosinophilic cytoplasmic inclusions were distributed in degenerated spinal ventral neurons. Ultrastructurally, the inclusions consisted of aggregations of granular dense material and a few vesicles. They reacted positively with polyclonal antibody against ubiquitin. The present case was diagnosed as equine motor neuron disease, which has recently been reported in North America and the United Kingdom.

View full abstract

The Rev protein of feline immunodeficiency virus (FIV) differentially transactivates the expression of viral structural proteins by allowing the accumulation of unspliced and singly spliced viral mRNA in cytoplasm via the Rev response element (RRE) at the end of env. To investigate the role of rev gene of FIV for the virus life cycle and cell tropism, we constructed the Rev expression plasmids, and functional activity of the Rev was assayed by using chloramphenicol acetyltransferase (CAT) assay system in feline and non-feline cell lines. Although the FIV Rev protein showed high transactivity to result in enhanced CAT production in a feline cell line, the productions of the CAT in non-feline cell lines were significantly lower than that in the feline cell line. These results indicate that specific cellular factor(s) present in feline cell line is required for the FIV Rev full-action and also suggest that the Rev action plays one of the important roles in determining the FIV cell tropism.

View full abstract

On June and August in 1989, cutaneous hemorrhagic parafilariasis was found in two cattle among 30 pregnant dairy cattle transported from Hokkaido to Chiba Prefecture. One adult female worm each was recovered from the blood spot in both cattle. Ivermectin oral administration, dosage rate of 200 μg/kg body weight, had no effect on the occurrence of the blood spots. Topical application of levamisole on a blood spot at a 2.5% concentration showed to stop the bleeding within a few minutes after treatment. This method was very easy to use at the farm situation where cutaneous hemorrhagic parafilariasis sporadically occurred. The disease has not been found in Chiba Prefecture on a whole since those cases in 1989.

View full abstract

The development of Babesia ovata in the salivary glands of nymphal Haemaphysalis longicornis ticks was morphologically studied for 4 days of feeding of tick on rabbits. Babesia ovata showed two forms (sporont and sporozoite) in the budding process. Sporozoites were formed in the acinar cells of salivary glands and released from the hollow cytoplasmic area of these cells by day 4 of feeding.

View full abstract