Isolation and identification of canine adenovirus type-2 from the upper respiratory tract of a dog

AIM: To report on the isolation and identification of canine adenovirus type-2 (CAV-2) from a greyhound dog with tracheitis/tonsillitis. METHODS: Virus isolation was performed with Madin and Darby canine kidney (MDCK) cell monolayers using standard virological techniques. The isolated virus was identified by haemagglutination inhibition and serum neutralisation tests. Viral DNA was extracted from infected MDCK cells and subjected to restriction endonuclease analysis using the endonuclease enzymes Bam HI, Bgl II, Eco RI and Hind III. RESULTS: A virus, designated 5 113-87, was isolated in MDCK cells yielding typical cytopathic effect. The virus could be neutralised with a CAV-2 specific reference antiserum and also showed some cross neutralisation with CAV-1 specific reference antiserum. The virus 5 113-87 had a high haemagglutination inhibition titre with CAV-2 antiserum using human group 0 red blood-cells and CAV-1 and CAV-2 reference antisera. This virus also had DNA restriction profiles identical to those of the reference CAV-2 (Toronto A26/61), whereas previously isolated strains of adenovirus from dogs in New Zealand had DNA restriction patterns identical to the prototype CAV-1 strain (Utrecht). CONCLUSION: The findings show that the virus 5 113-87 isolated from the upper respiratory tract of a dog in New Zealand is CAV-2.     

Isolation of a subgroup two adenovirus from calf with weak calf syndrome.

A viral agent, designated Id-1, was isolated from the buffy coat of a calf suffering from weak calf syndrome. The virus replicated on bovine salivary gland cells and caused cytopathic effect within four days after infection-Cytopathic effect was characterized by rounding and clumping of cells. Stained preparations of infected monolayers revealed multiple intranuclear inclusions. The agent was found to be resistant to chloroform, ether, trypsin, sodium desoxycholate, oxytetracycline and a pH range of three to nine. The virus was sensitive to 5-iodo-2'-deoxyuridine and to a temperature of 70 degrees C. Cross neutralization tests with Id-1 antiserum and bovine adenovirus type 7 (strain Fujuroi) antiserum resulted in complete neutralilation of both viruses with four or less antibody units of homologous or heterologous antiserum.     

Acute respiratory distress syndrome (ARDS) in lambs. Hematology

Lambs suffering from Acute Respiratory Distress Syndrome (ARDS) showed elevated PCV, neutrophilia, a tendency towards lymphopenia, eosinopenia, hyperphosphatemia, hypoglycemia and extremely low serum Ca values during the first couple of days after the outbreak of symptoms. During the very early phase, plasma potassium values were mostly lowered (Figs. 1-3, Table I). The possible involvement of histamine is shortly discussed: either 1) through an atopic reaction, 2) because of acute ruminal acidosis and sudden histamine formation, or 3) involvement of endotoxins.     

Reinfection of lambs with bovine respiratory syncytial virus.

Eight lambs which were experimentally infected with bovine respiratory syncytial virus (RSV) when they were six to eight weeks old were challenged with the same virus seven months later. After reinfection, lambs developed mild clinical disease and the virus was isolated from nasal swabs from three lambs and peripheral blood from two lambs. Reinfection resulted in changes in peripheral blood cell populations. There was an early increase in the number of CD8+ T lymphocytes and B (LCA p220+) lymphocytes but the proportions of CD4+ and CD4-CD8- T lymphocytes were significantly reduced. Peripheral blood mononuclear cells obtained from lambs reinfected with bovine RSV showed significantly higher responses to bovine RSV antigen in vitro than those obtained from control lambs but their responses to the mitogen phytohaemagglutinin were significantly lower than in control lambs. RSV-specific IgG, IgM and IgA levels of serum samples obtained 10 days after challenge were significantly higher than those of serum samples obtained before challenge.     

Experimental adenovirus infection of lambs

An untyped adenovirus, designated WV419/75, which was isolated from an apparently healthy lamb, was inoculated into lambs by the combined intranasal and intratracheal routes. A mild respiratory illness was produced. At post-morten examination, 4, 7, 14 and 21 days post inoculation (p.i.) irregular areas of atelectasis were observed and consolidation was present in the worst affected lungs at 7 days p.i. Histologically the principal lesion was a proliferative bronchiolitis which extended to bronchopneumonia at 7 days p.i. The most striking feature of the bronchiolitis was prominent cytomegaly and karyomegaly of epithelial cells, some of whose nuclei contained large basophilic inclusion bodies consisting of crystalline arrays of virus particles.Virus was isolated primarily from the upper and lower respiratory tract but was also found in spleen, mesenteric lymph node, small intestine, kidney and brain at 4 to 7 days p.i. However, viral lesions were confined to the respiratory tract.Attempts to exacerbate the disease by the administration of dexamethasone or Pasteurella haemolytica were unsuccessful.     

Isolation and characterization of an adenovirus and isolation of its adenovirus-associated virus in cell culture from foals with respiratory tract disease.

An adenovirus was isolated from a foal with respiratory tract disease. The virus produced cytopathic effects (CPE) in equine embryo kidney (EEK) cell culture, contained deoxyribonucleic acid (DNA), was resistant to chloroform and pH 3, and was moderately resistant to heat. The virus caused hemagglutination of human (type O) erythrocytes. Viral density was 1.34 g/cm,3 and diameter was 75 nm. An adenovirus-associated virus (AAV) isolated from the infected cell culture was 22 nm in diameter. These viruses are classified as equine adenovirus and equine AAV.     

Isolation of bovine adenovirus type 7 from calves with pneumonia and enteritis.

Bovine adenovirus type 7 was isolated from a 10-month-old calf with fibrinopurulent pneumonia and from 2 newborn calves with pneumoenteritis. The viruses were isolated on calf lung and adrenal gland cell cultures and were identified as serotype 7 by immunoelectron microscopy and serum-neutralization tests.     

3-Methylindole-induced pulmonary injury in lambs. A comparison with acute respiratory distress syndrome (ARDS)

Five to six month-old lambs of two different Norwegian breeds (Dala and Rygja) were dosed with 3-methyl indole (3MI) and DL-tryptophan (DL-T), and examined clinically, hematologically and post mortem. Results were compared with the findings in Acute Respiratory Distress Syndrome (ARDS), a condition of acute dyspnea occurring in 5-6 month-old lambs (of Dala and Spael breeds) after they have been moved from mountain pastures onto lush aftermath in September. The results show that such young Norwegian lambs are susceptible to 3MI-dosing, and that the symptoms and lesions were similar to those described earlier in connection with 3MI-dosing in cattle and adult sheep. The results clearly demonstrate that 3-MI-induced pulmonary injury in lambs differs from ARDS as far as both symptoms, hematology and pathology are concerned.     

Acute respiratory distress syndrome (ARDS) in lambs. Clinical and pathoanatomical investigations

In the South-Western part of Norway, lambs of the Old Norwegian short tailed breed (Spael) and crosses with the Dala breed sometimes develop an Acute Respiratory Distress Syndrome (ARDS) shortly after they have been moved onto lush aftermath grazings from mountain pastures. This article covers the symptoms and pathoanatomical findings in lambs affected with ARDS (Table I). The lambs acquired ARDS 18-72 hours after change of pasture. Heavy dysphne, frothing at the mouth, elevated temperature (greater than 41 degrees C), tachycardia, urination and ruminal atony were striking symptoms (Table II). In the early phase of the disease the lambs were often in a tranquil state, depressed, sometimes atactic, and it seemed that they went into the overt dysphneic phase on exposure to physical stress. Morbidity was 1.4%, mortality 36%. Post mortem findings included frothy contents in the airways, heavy congestion and oedema in the lungs which also had emphysematous areas, subepicardial petechiae, varying degree of mottling of the myocardium, and also varying degree of paleness and spottyness of renal cortices. The lungs showed extensive focal alveolar and interstitial emphysema, septal congestion, alveolar oedema, partial collapse, and accumulations of polymorphonuclear leucocytes in vascular beds. Later, fibrillar material was found in the alveoli, alveolar macrophages accumulated, and interalveolar septa thickened because of increased fibromuscular tissue and mononuclear cells (Fig. 1, A-D). Alveolar epithelial hyperplasia was not seen in any stage. Four lambs were moderately infected with lungworms (D. filaria), three in the prepatent, one in the patent phase. Histopathological changes in other organs included granular degenerations of myocardial threads, and development of a glomerulonephritis and focal interstitial nephritis (Fig. 1, E-F). This disease entity (ARDS) in lambs seems to be unknown in literature. The disease is compared with other known diseases in ruminants. Etiology is so far unknown. Possibilities of sudden ruminal histamine formation coinciding with a hypersensitivity reaction is discussed.     

Experimental infection of lambs with an adenovirus of ovine origin

A New Zealand isolate of ovine adenovirus, designated WV757/75, was inoculated into caesarian-derived lambs by the combined intranasal and intratracheal routes. A mild illness was produced. This was characterized by fever, nasal discharge and some coughing. Pathological changes were mild and were confined to the lung. Virus was isolated from the upper and lower respiratory tracts at 4 and 7 days post innoculation (p.i.) and from the kidneys at 4,7,10 and 14 days p.i. Neutralizing antibody was first detected in serum at 7 days p.i. and tissue rose to an average of 10^5.0 at 14 days.     

Isolation of an adenovirus and an adeno-associated virus from goat kids with enteritis.

A dairy goat operation in Minnesota experienced a sudden, markedly increased mortality among its neonatal goats. Approximately 60 of 130 kids (46%) died. The animals had diarrhea and dyspnea of 1-2 days duration before death. Necropsy of 4 goat kids revealed marked, acute, catarrhal enteritis and fibrinous pleuropneumonia. Mannheimia haemolytica was isolated from the lungs. Basophilic inclusion bodies filling the entire nucleus were present in enterocytes of the ileum of 3 goats. Adenoviral particles were detected in the feces by electron microscopy and adenovirus was subsequently isolated from the intestinal content together with a parvo-like virus (dependovirus). Morphology, physicochemical characteristics, and neutralization tests indicated that the adenovirus resembled ovine adenovirus-2 (OAdV-2). However, the PstI restriction endonuclease pattern produced by the goat adenovirus was distinct from that of OAdV-2. This is the first report of enteritis in goats with an adenovirus antigenically related to OAdV-2 and with a parvo-like dependovirus.     

Isolation of bovine adenovirus type 4 from cattle in Oregon.

Four isolates of bovine adenovirus type 4 were recovered from Oregon cattle. One isolate was recovered from a 1-week-old calf with pneumoenteritis, and 1 isolate from an 8-month-old bull with fever and respiratory disease. Two isolates were recovered as latent viruses in testicular cell cultures. All 4 isolates of the virus were shown to have certain physical, chemical, biologic, and antigenic characteristics similar to previously described strains of bovine adenovirus type 4. Of 246 adult beef and dairy cattle in Oregon, 51% had serum-viral neutralizing antibodies to the type 4 virus at the 1:8 dilution level.