Biomedical subjects

R C Cutlip

Publications and source records attributed to R C Cutlip.

At least 91 records · Page 5Linked to original sources

PubMed1982

Experimentally induced parainfluenza type 3 virus infection in young lambs: pathologic response.

Pulmonary changes in five 1-week-old, colostrum-deprived lambs transtracheally inoculated with parainfluenza type 3 virus were studied by immunofluorescent, microscopic, and ultrastructural techniques. The lambs were killed at postinoculation days (PID) 3, 5, and 7. Immunofluorescence specific for parainfluenza type 3 virus was first seen in small airways and alveolar epithelium and later in the lumens of airways and alveoli and, to a lesser extent, in the interstitium of the lungs. Grossly, there were multifocal areas of consolidation in all lobes of the lungs. These areas were characterized microscopically by bronchiolitis and interstitial pneumonitis. The bronchiolitis involved the terminal airways and consisted of necrosis and sloughing of epithelial cells followed by hyperplasia of the epithelium. The interstitial lesion comprised extensive infiltration of alveolar septa and alveoli with macrophages and the necrosis of alveolar epithelium. This was followed by hyperplasia of the epithelium. Degenerated bronchiolar and alveolar epithelium contained numerous intracytoplasmic inclusions early in the infection, but such inclusions were not seen in the lambs killed at PID 7. The degenerated changes were also seen with the electron microscope, as were numerous inclusions of viral nucleoprotein and a few viral buds at PID 3 and 5. Viral inclusions and buds were seen in ciliated and nonciliated bronchial epithelial cells and type I and type II alveolar epithelial cells.

Animals↗

PubMed1982

Vaccination studies of aspergillosis in turkeys: subcutaneous inoculation with several vaccine preparations followed by aerosol challenge exposure.

Five vaccines were prepared from an isolate of Aspergillus fumigatus: a culture filtrate vaccine (I), a spore vaccine (II), a mycelial vaccine (III), and 2 germling vaccines (IV and V). The 2 germling vaccines were produced on different media. Two experiments were conducted to test the vaccines for efficacy in groups of 21 turkey poults by giving each bird 2 subcutaneous inoculations of the respective vaccine at 1 and 2 weeks of age. The birds were challenge exposed to an aerosol of spores of A fumigatus at 1 month of age. The 2 experiments differed only in the challenge exposure. In experiment 1, 38% of the poults were protected when vaccinated with an A fumigatus germling vaccine (IV) and challenge exposed with a dose of aerosolized A fumigatus spores that killed 100% of the nonvaccinated controls. Onset of postchallenge-exposure deaths were delayed by 2 days in the turkeys given vaccine IV. In experiment 2, 48% of the poults were protected when given germling vaccine IV, whereas 62% to 86% of the poults in the nonvaccinated and 3 other vaccine groups died. In experiment 2, 50% of the poults given a mycelial vaccine (III) were protected. Torticollis was a frequent sign of the disease in experiment 2.

Aerosols↗

PubMed1982

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: immunofluorescent and electron microscopic studies.

Colostrum-deprived lambs were inoculated transtracheally with respiratory syncytial virus (RSV), Pasteurella haemolytica, or RSV and P haemolytica. Multiple tissues were examined by immunofluorescence to localize viral and bacterial antigens, and lungs were examined by electron microscopy for cytopathologic changes. Using immunofluorescence, viral antigen was detected only in the respiratory tract, mainly in the bronchial and bronchiolar epithelium and in the alveolar wall. Lesser amounts of viral antigen were detected in the surface epithelium of the nasal turbinates and trachea. Bacterial antigen was not detected. Ultrastructurally, the lambs inoculated with P haemolytica or with RSV and P haemolytica had increased numbers of type II pneumocytes, necrotic epithelial cells, neutrophils, and macrophages and excessive cellular debris in multiple foci in the lungs. Bacterial were seen only infrequently; they were within phagocytic vacuoles of neutrophils and macrophages and were free within pulmonary septa. In lambs inoculated with RSV or with RSV and P haemolytica, cells in the epithelium were multinucleated. Viral buds were seen on cytoplasmic membranes of ciliated and nonciliated cells of bronchial and bronchiolar epithelium. Isolated epithelial cells were necrotic. Viral nucleoprotein was prevalent in a few alveoli, free or within vacuoles of phagocytic cells. Necrotic debris and phagocytic cells were more prominent in the alveoli of lambs inoculated with RSV and P haemolytica than in those of lambs inoculated with either agent alone.

Animals↗

PubMed1982

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: pathologic studies.

Nineteen 4-week-old, colostrum-deprived lambs were transtracheally inoculated with respiratory syncytial virus (RSV), Pasteurella haemolytica biotype A serotype 1, or RSV and P haemolytica. Pneumonic lesions were more frequent, more extensive, and more severe in lambs inoculated with RSV and P haemolytica than in lambs inoculated with either agent alone. Lesions were seen in 2 of 4 lambs inoculated with P haemolytica alone, in 3 of 4 lambs inoculated with RSV alone, and in 11 of 11 lambs inoculated with RSV and P haemolytica. Grossly, lambs given P haemolytica alone had fibrinous pleuritis and pneumonic lesions with hemorrhagic and necrotic centers which involved approximately 14% of the lung surface. Lambs inoculated with RSV alone had multifocal areas of consolidation and hemorrhage that involved 5% of the lung surface. Lambs in 2 groups inoculated with RSV and P haemolytica had lesions characteristic of both agents over 15% to 21% of the lung surface. Histologically, P haemolytica alone caused acute fibrinous pneumonia with necrosis of the lung parenchyma and fibrinous pleuritis; RSV alone caused interstitial pneumonitis, bronchiolitis, and hemorrhage. In combination, the agents caused interstitial pneumonitis and severe exudative pneumonia with focal necrosis and hemorrhage. Lesions seen in lambs given RSV and P haemolytica or in lambs given P haemolytica alone were grossly and histologically similar to those seen in naturally occurring cases of acute pneumonic pasteurellosis. Seemingly, the virus caused a lesion that compromised the lungs and thus permitted P haemolytica to become established and to produce a more severe pneumonic lesion than it could produce alone.

Animals↗

PubMed1982

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: clinical and microbiologic studies.

Four-week-old lambs were inoculated transtracheally with respiratory syncytial virus (RSV), Pasteurella haemolytica, or RSV and P haemolytica. When given in combination, RSV administration preceded P haemolytica by 3 or 5 days. Lambs inoculated with P haemolytica or RSV developed a mild respiratory tract disease accompanied by a transient pyrexia in a few lambs. By 24 hours after inoculation of bacteria, all lambs inoculated with RSV and P haemolytica were listless, reluctant to move, and exhibited hyperpnea and dyspnea. Most lambs had pyrexia and a few coughed and had serous nasal discharge. These clinical signs persisted for 3 to 4 days and were more pronounced in those inoculated with P haemolytica 5 days after RSV than in those inoculated with P haemolytica 3 days after RSV. Respiratory syncytial virus was isolated from 8 of 15 inoculated lambs and P haemolytica was isolated from 12 of 15 inoculated lambs. All lambs responded serologically to RSV, but none responded to P haemolytica.

Animals↗

PubMed1982

Sheep pulmonary adenomatosis (jaagsiekte) in the United States.

Morphologic features of 8 cases of sheep pulmonary adenomatosis in the United States are described. All cases were studied by light microscopy and 1 case, by electron microscopy. The common finding in all sheep was an adenoma composed of fetal type II alveolar epithelial cells. The stroma closely resembled interalveolar septa in most areas. In other areas, there was excessive collagenous or myxomatous tissue. Metastatic tumor in mediastinal lymph nodes of 2 sheep closely resembled tumor in the lung. A virus with cultural and structural characteristics like those of ovine progressive pneumonia virus was isolated from the lungs of 1 sheep, but neither virions nor viral inclusions were seen in the pulmonary parenchyma.

Animals↗

PubMed1981

Susceptibility of vaccinated swine and mice to generalized infection with specific serotypes of Erysipelothrix rhusiopathiae.

Swine were vaccinated with adsorbate bacterin made from Erysipelothrix rhusiopathiae of serotype 2 and were subsequently allotted to 4 exposure groups, each of which was exposed to 1 of the strains of E rhusiopathiae of serotypes 1, 2, 9, or 10. Mice were vaccinated with the same bacterin and were subsequently allotted to 60 exposure groups which were exposed to 60 strains of E rhusiopathiae, comprising 10 strains each of serotypes 1, 2, 4, 9, 10, and 11. Response to challenge of immunity in swine was determined by the presence of clinical signs of acute generalized erysipelas; response in mice was determined by the quantal (live-dead) method. Vaccinated swine were as susceptible to the strain of serotype 10 as were nonvaccinated control swine, whereas vaccinated swine were immune and control swine were susceptible to the strains of serotypes 1 and 2. The strain of serotype 9 was not sufficiently virulent to induce acute generalized erysipelas, even in control swine. Arthritis was not prevented by vaccination, but its frequency and severity were less in vaccinated swine exposed to strains of serotype 1 or 2 than in those exposed to strains of serotype 9 or 10. Vaccinated mice were significantly (P less than 0.05) more susceptible to the strains of serotype 10 than to those of any other serotype tested.

Animals↗

PubMed1981

Intrauterine transmission of ovine progressive pneumonia virus.

Ovine fetuses, newborn lambs, and ovine colostrum were examined for ovine progressive pneumonia virus. The lambs and colostrum were also examined for specific antibody. Virus was isolated from 1 fetus, from 2 newborn lambs, and from most samples of colostrum. The fetus was about 100 days old and was carried by a seronegative ewe in contact with seropositive sheep. Both newborn lambs were carried by seropositive ewes. One lamb was dead at birth; the other lamb was normal and had not nursed. Antibody specific for the virus was present in the colostrum of 12 of 14 seropositive ewes and in the serum of 8 of 11 lambs that had nursed seropositive ewes, but not in the serum of lambs that had not nursed.

Animals↗

PubMed1981

Effects of aflatoxin consumption on the clinical course of swine dysentery.

Specific-pathogen-free pigs were examined for susceptibility to swine dysentery after daily treatment with aflatoxin B1 (0.07 to 0.14 mg/kg). In the pigs (group II) given both aflatoxin and Treponema hyodysenteriae, the incubation period before the onset of swine dysentery was shorter than that in pigs (group III) given T hyodysenteriae alone. Also, the number of days in which infected pigs showed signs of diarrhea and dysentery was greater in the group given aflatoxin and T hyodysenteriae than in the group given T hyodysenteriae alone. Four of 8 pigs given aflatoxin and T hyodysenteriae died during the experiment, whereas only 1 of 8 infected pigs in the other group died. Pigs in both groups, convalescent from swine dysentery, were immune to rechallenge exposure. Subclinical effects of aflatoxin consumption were evident at necropsy, but clinical signs and lesions of swine dysentery were not observed in group III pigs (given aflatoxin only).

Aflatoxins↗

PubMed1980

Morphogenesis and structure of caprine respiratory syncytial virus.

Cell cultures inoculated with caprine respiratory syncytial virus (RSV) were studied with light, fluorescent, and electron microscopy to determine the morphogenesis and structure of the virus. Small syncytia were seen after 36 hours in culture. After 48 hours in culture, syncytia were large and numerous and pleomorphic cytoplasmic inclusions were seen. These inclusions were more pronounced and numerous later in the infection cycle. Indirect immunofluorescence revealed a diffuse to granular cytoplasmic fluorescence with fluorescing fibrils on the cell surface. With the electron microscope, filamentous (100-160 nm) and spherical (90-160 nm) particles were seen budding off the cell membrane. The number of virus buds diminished with increased size of syncytia. Granular pleomorphic cytoplasmic inclusions were seen near the nucleus, and electron dense masses were seen just beneath the cytoplasmic membrane where large quantities of virus were budding from the cell surface. The first type of inclusion had distinct borders; the second diffuse borders and appeared to contain viral nucleoprotein. Negative staining revealed spherical, pleomorphic, and filamentous forms of the virus; the last form predominated. The virions were covered with club-shaped projections, and the nucleocapsids were seen as fragile strands frequently broken into fragments or as isolated rings. Morphogenesis and structure of the caprine RSV places this virus with the Pneumovirus genus of the Paramyxoviridae family.

Animals↗

PubMed1980

Ultrastructure of renal lesions in pigs with acute leptospirosis caused by Leptospira pomona.

Twelve 4-day old, pathogen-free pigs were inoculated intraperitoneally with virulent L. pomona. Two pigs each were killed 1, 2, 3, 5, 7, and 14 days after inoculation and their kidneys examined by light and electron microscopy. Three to 5 days after inoculation there was hyperemia, edema and swelling of tubular epithelium; leptospires were detected intravascularly, in interstitium and embedded within basement membranes. At day 7, leptospires were at basal surfaces of proximal tubules and in phagosomes in tubular epithelium. Perivascular aggregates of monocytes and macrophages were prominent. At day 14, intersitial cells were chiefly plasmacytes and lymphocytes. Leptospires were only on tubular epithelial cell surface microvilli. In another experiment, all pigs receiving low-virulent strains had leptospires in the renal interstitium at 7 days after inoculation but had none at 14 days. All low-virulent strains produced degenerative changes and lymphocyte-plasmacytic infiltration. These studies indicate that non of the low-virulent isolates were acceptable for use in vaccines. Fialure of leptospires to remain attached to microvilli of proximal tubules in late stages of acute infection may be related to differences in virulence of various isolates.

Anemia↗

PubMed1980

Lesions in clinically healthy cattle persistently infected with the virus of bovine viral diarrhea--glomerulonephritis and encephalitis.

Four clinically healthy cattle persistently infected with the virus of bovine viral diarrhea were examined for viral antigen and lesions. Antigen was seen by direct immunofluorescence in cytoplasm of the neurons of the brain and cervical part of the spinal cord, cells and basement membrane of renal glomeruli, reticular cells of lymph nodes and spleen, epithelial cells of small intestinal crypts and renal and testicular tubules, and endothelial cells of blood vessels. Infected neurons were pyknotic and surrounded by astrocytes and macrophages. A few blood vessels in the brains were cuffed with mononuclear cells. Basement membranes of renal glomeruli were irregularly thick with eosinophilic material, and mesangial cells in the glomeruli were plentiful. The virus had a direct effect on some tissues, but was restricted in its cytopathogenicity and was not eliminated by defense mechanisms of the host. Renal glomerular lesions were believed to have an immunologic basis.

Animals↗

PubMed1979

Reproductive performance of apparently healthy cattle persistently infected with bovine viral diarrhea virus.

A Holstein-Friesian bull and three Holstein-Friesian cows were seronegative for bovine viral diarrhea (BVD) virus but were persistently infected with the virus. Virus was isolated from buffy coat cells and nasal and lacrimal secretions during their lifetime, and they remained free of clinical signs of BVD. The three cows were pregnant when purchased, and they gave birth to full-term calves. One calf lived only a few hours, one calf became ill and died within a few days, and one calf became ill and was euthanatized within a few weeks. One cow was then bred and became pregnant but aborted a 7-month fetus. A second cow was bred approximately 5 months after parturition but did not conceive. The third cow was necropsied 6 weeks after calving, because of loss of weight. Although the bull's semen contained BVD virus when seropositive cows were bred, normal calves were born. When seronegative heifers were bred, they became seropositive to BVD virus within two weeks, with higher titers in six weeks. On heifer conceived after one service but aborted a 6-month fetus. Three others continued to have estrous cycles until their titers rose to 1:128, then they conceived and gave birth to normal calves. Another heifer conceived on the first service, had a titer of 1:128 two weeks after breeding, and gave birth to a normal calf.

Animals↗

PubMed1979

Experimentally induced respiratory syncytial viral infection in lambs.

Signs of clinical illness, lesions, and seroconversion were observed in lambs experimentally inoculated with a respiratory syncytial virus of bovine origin. Signs of clinical illness were mild and consisted of fever and hyperpnea. Multifocal areas of interstitial pneumonia were seen in lambs necropsied during the period of clinical response. All lambs seroconverted to viral antigen, and the virus was isolated from two of the lambs.

Animals↗

PubMed1979

Lesions of ovine progressive pneumonia: interstitial pneumonitis and encephalitis.

Lesions in sheep with ovine progressive pneumonia are described. Lungs were mottled grayish-pink, firm, and large (two to three times normal weight). There was chronic diffuse interstitial pneumonitis characterized by extensive hyperplasia of lymphoid cells around airways and blood vessels and by accumulation of mononuclear cells in the interstitium. In some lungs, this reaction was accompanied by excessive fibrous tissue and smooth muscle and less frequently by hyperplastic epithelium of terminal bronchioles and alveoli. Secondary bronchopneumonia was common. Lymphocytic meningitis, choroiditis, and leukoencephalitis were seen in a few sheep. Meninges and choroid plexuses were infiltrated with lymphoid cells, and subependymal blood vessels were cuffed with lymphoid cells. Much subependymal white matter was demyelinated and had foci of necrosis and gliosis.

Animals↗

PubMed1979

Lesions in lambs experimentally infected with bovine respiratory syncytial virus.

Respiratory syncytial virus was inoculated intratracheally into five 1-week-old lambs. Three of the lambs responded clinically with fever, hyperpnea, and listlessness. Pulmonary lesions consisted of multifocal areas of consolidation, with necrosis of individual epithelial cells of the airways and accumulation of necrotic debris, macrophages, and few neutrophils in terminal airways and alveoli. Pulmonary septa in affected areas were infiltrated with numerous macrophages and lymphocytes. Viral particles were seen as buds on epithelial cells and free in bronchioles and alveoli.

Animals↗

PubMed1979

Experimental respiratory syncytial virus infection in feeder-age lambs.

Signs of disease, lesions, and serologic response were seen in six 6-month-old-lambs experimentally inoculated with respiratory syncytial virus (RSV). A transient febrile response, mild hyperpnea, and listlessness were seen. Multifocal areas of interstitial pneumonia and bronchiolitis were seen in lambs necropsied during the period of clinical response. A serologic response to RSV was seen in all lambs, and RSV was recovered from five lambs.

Age Factors↗

PubMed1978

Diagnostic features of ovine progressive pneumonia.

Ovine progressive pneumonia, a chronic, insidious disease of adult sheep, has a relentless course leading to dyspnea, emaciation, and death. Clinical observations and serologic tests are adequate for making a tentative diagnosis. The agar gel immunodiffusion test seems to be the best serologic procedure for indicating infection with the virus but cannot be used to predict morphologic changes or clinical disease, inasmuch as many clinically unaffected animals carry the virus. A definitive diagnosis is based on finding lesions and isolating virus. Affected lungs are large and heavy as a result of interstitial accumulation of lymphoid cells and fibromuscular tissue. Frequently, interstitial lesions are accompanied by bronchopneumonia from secondary bacterial infection. The causal virus can be isolated from infected lungs by cocultivation with primary ovine or bovine cells.

Animals↗