Search PubMed⌕ Search

Biomedical subjects

R Ducatelle

Publications and source records attributed to R Ducatelle.

At least 145 records · Page 8Linked to original sources

Taxon 20 (Fam. Pasteurellaceae) infections in European brown hares (Lepus europaeus).

Hemolytic bacteria, phenotypically related to organisms previously identified as Pasteurella haemolytica and tentatively named Taxon 20, were isolated from cases of purulent bronchopneumonia and from conjunctivitis in European brown hares (Lepus europaeus). The bronchopneumonia, sometimes accompanied by lesions in other organs, occurred without other concomitant disease. The conjunctivitis was found mainly in animals suffering from the European brown hare syndrome.

Animals↗

Type A2 congenital tremor in piglets.

A neonatal congenital tremor (CT) syndrome that sporadically occurs in Belgian piglets is described. The results of an epidemiologic follow-up survey on affected farms is presented. Experimental trials to provoke this syndrome by inoculation of a brain suspension, derived from CT-piglets, in pregnant sows by intramuscular and intrauterine way, partly succeeded. Histological and biochemical studies on brain tissue of these piglets indicated that this form of CT should be classified as an A2 form. Using serologic and virologic examinations we were however not able to identify the probably infectious CT-agent.

Animals↗

Morphometric evaluation of myofibrillar hypoplasia in splayleg piglets.

A morphometric method was applied to evaluate the EMS (extramyofibrillar space) in cross-sections of the musculus adductor as a parameter for the grading of the myofibrillar hypoplasia in splayleg piglets. Although there was a great variability between the individual piglets for the EMS values, a highly significant difference between normal and splayleg piglets was noted. Using this method it was found that myofibrillar hypoplasia indeed is associated with the splayleg syndrome.

Animals↗

Mannosidosis in a litter of Persian cats.

Three kittens in a litter of Persian cats showed, from the age of eight weeks, tremor, ataxia, dysmetria, progressive weakness and emaciation. Cytoplasmic vacuolation was observed in neurons, mesenchymal and epithelial cells of tissues taken post mortem. The alpha-mannosidase activity of brain tissue of one cat tested was 4.8 per cent of control values and the urine of two cats contained large amounts of mannose-rich oligosaccharides.

Animals↗

Spontaneous and experimental myofibrillar hypoplasia and its relation to splayleg in newborn pigs.

The relation of myofibrillar hypoplasia to clinical splayleg was studied. A strain of Belgian Landrace sows was selected for this study because they produced pigs which had no myofibrillar hypoplasia. Myofibrillar hypoplasia could nevertheless by induced experimentally in these animals by dexamethasone treatment of the sows during late pregnancy. The lesion was observed without clinical signs and was compared to the myofibrillar hypoplasia in clinical cases of splayleg. The differences between these 2 groups may account for the appearance of clinical signs. These differences included the maturity of the myofibrils and the degree of autophagolysosomal glycogen breakdown.

Animals↗

Immunoperoxidase study of adenovirus pneumonia in dogs.

The pathology of adenovirus pneumonia in 16 dogs is described. Clinically, these dogs had been severely ill, with severe dyspnoea and listlessness, but only faint coughing. Histopathological lesions could be associated directly with the presence of adenovirus antigens in the lungs of these dogs by using an unlabelled immunoperoxidase technique on paraffin tissue sections. The lesions were focal and located in alveoli and bronchioles. Infected cells were mostly alveolar macrophages and less frequently type 1 and 2 pneumocytes and bronchiolar epithelial cells. Infiltrating neutrophils and lymphocytes were not observed to be infected. This type of pneumonia appears to be a fairly well defined clinical and pathological entity in kennel dogs.

Adenoviridae Infections↗

Space occupying lesions of cranial nerves in calves with facial paralysis.

Clinical and pathological data of a recently discovered neurological disorder in young calves were studied. The symptoms were those of a paralysis of the nervus facialis and a dysfunction of the nervus vestibulocochlearis. Macroscopically, space occupying lesions were found at the roots of these two cranial nerves and in some cases further on their course into the os petrosum. On histological examination, these legions contained multiple nodules with mainly histiocytic cells, some plasma cells and multinucleated giant cells. Around these nodules, dense bands of connective tissue with fusocellular fibroblasts, some plasma cells and small blood capillaries were present. The nodular lesions were usually in close contact with the nerve. Ultrastructurally, a variety of cells, predominantly histiocytes and some plasma cells, were seen next to Schwann cells which contained degenerating axons.

Animals↗

Significance of lysosomes in the morphogenesis of coronaviruses.

Virus-containing electron-dense membrane-bound cytoplasmic bodies are described in tracheal epithelial cells of chickens infected with Infectious Bronchitis Virus and in intestinal epithelial cells of swine infected with Porcine Epidemic Diarrhea Virus. Using silver-methenamine staining, phosphotungstic acid staining and acid phosphatase enzyme cytochemical staining of ultra-thin sections, these bodies were shown to be virus-containing secondary lysosomes and residual bodies. The accumulation of viral particles in the lysosomes is suggested to possibly represent an intracellular defense mechanism. However, no morphological alterations were found indicating a destruction of the viruses by the lytic lysosomal enzymes.

Animals↗

Demonstration of pseudorabies viral antigen in thick and ultrathin tissue sections of young pigs using an immunogold method.

Pseudorabies (Aujeszky's) virus antigens were labeled in thick and ultrathin tissue sections of young pig brain and liver tissue, using an indirect immunogold method. Antigens were tagged with 20 nm gold particles. Controls proved the specificity of the reaction in paraffin sections and ultrathin epoxy sections. Immunogold staining was compared with immunoperoxidase staining in paraffin sections. In ultrathin sections stained with the immunogold method, the gold particles were present on viral nucleocapsids and viral envelopes, as well as on a number of other intracellular structures. These included the inner nuclear membrane, the nucleoplasm, intranuclear filaments, the endoplasmic reticulum, and free cytoplasmic polyribosomes. Gold particles were absent on mitochondria and microtubules. In paraffin sections, immunogold labeling for pseudorabies virus antigen was less sensitive than immunoperoxidase staining. Immunogold staining of ultrathin tissue sections can yield additional information on virus-host cell interactions.

Animals↗

Immunoperoxidase study of canine distemper virus pneumonia.

Forty-two cases of canine pneumonia were examined for the presence of canine distemper virus. For that purpose canine distemper virus inclusion bodies were located. The histopathological lesions were related to the presence of canine distemper antigen, as demonstrated with an immunoperoxidase technique. This technique was more sensitive for detecting canine distemper infection in lung tissue than was the study of inclusion bodies. Attention was also paid to combined infection with canine adenovirus and Bordetella bronchiseptica.

Adenoviridae Infections↗

Dual adenovirus and distemper virus pneumonia in a dog.

A case of simultaneous infection of the lungs of a dog with canine distemper virus (CDV) and canine adenovirus (CAV) is described. The techniques employed are histological stains, immunoperoxidase technique, and transmission electron microscopy. Two viruses are shown to infect the same cells. The significance of dual infection of the same cells is discussed in comparison with literature data on in vitro experiments.

Adenoviridae Infections↗

Pathology of experimental CV777 coronavirus enteritis in piglets. I. Histological and histochemical study.

Sixteen cesarean-derived colostrum-deprived piglets were infected oronasally with CV777 coronavirus on the second or third day of life. Two uninfected piglets were controls. They were killed at 96 and 120 hours after birth. After an incubation period of 22 to 36 hours, all principals showed severe diarrhea. The principals were killed between 12 and 120 hours after infection. Exfoliation of enterocytes were seen first in the piglet killed 24 hours after infection (two hours after the diarrhea began). From that time on, shortening and fusion of villi was present in all small intestinal parts. Affected cells showed vacuolation. The histochemical study showed that infected piglets had decreased activity of all four enzymes studied. The light microscope showed no lesions in the absorptive colonic epithelium. The significance of the lesions in relation to intestinal dysfunction is discussed, and lesions are compared to those of transmissible gastroenteritis and porcine rotavirus infection.

Animals↗

Pathology of experimental CV777 coronavirus enteritis in piglets. II. Electron microscopic study.

Sixteen cesarean-derived, colostrum-deprived piglets were infected oronasally with CV777 coronavirus on the second or third day of life. Two uninfected piglets were controls. After an incubation period of 22 hours to 36 hours, all principals showed severe diarrhea. The piglets were killed at different time intervals. Viral particles were found in the jejunal villous epithelial cells from 18 hours after infection until four days after the beginning of diarrhea. In the colonic epithelial cells, viral particles and degenerative lesions were found only in the piglet killed 36 hours after onset of diarrhea. Degenerative lesions in the enterocytes began at 18 hours after infection and were most pronounced in the jejunum at the onset of clinical signs. From 24 hours on after the onset of clinical signs, three cell types were found: degenerated virus-containing enterocytes; cuboidal cells; and columnar, highly vacuolated cells containing lipid droplets.

Animals↗

Sequential pathological study of experimental porcine adenovirus enteritis.

The sequential enteric lesions of experimental porcine adenovirus strain 6618 infection were studied in 18 hysterotomy-derived, colostrum-deprived piglets, by histology, transmission electron microscopy, and an immunoperoxidase technique. Viral particles could be seen in altered epithelial cells of the lower small intestine from 24 hours until 16 days after inoculation. With the immunoperoxidase technique, viral antigen could be found in epithelial cells at 45 days after challenge. Destruction of epithelial cells and shortening of villi could be related directly to the presence of the virus. Histology of the lower jejunum and ileum, which demonstrates intranuclear inclusion bodies, is proposed as a useful diagnostic technique.

Adenoviridae Infections↗