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R C Cutlip

Publications and source records attributed to R C Cutlip.

At least 37 records · Page 2Linked to original sources
PubMed1997

Pathogenesis of infection induced by an adenovirus isolated from a goat.

OBJECTIVE: To determine the pathogenic potential of an adenovirus isolated from a goat. ANIMALS: 14 colostrum-deprived, isolation-reared goat kids approximately 3 weeks old. PROCEDURE: Kids were inoculated with either cell culture fluid containing adenovirus (n = 10) or uninfected cell culture fluid (n = 4): 2 ml transtracheally and 1 ml/nostril. Clinical signs of disease and rectal temperature were recorded daily; nasal secretion and fecal specimens were collected daily. Control kids were necropsied, 2/d, on postinoculation days (PID) 5 and 10. Virus-inoculated kids were necropsied on PID 3, 5, 7, 10, and 28. After necropsy, lung, liver, kidney, and brain specimens were aseptically collected for virus isolation attempts. Tracheal fluid was collected on sterile cotton swabs. Turbinate, trachea, lung, mediastinal lymph node, liver, kidney, duodenum, jejunum, ileum, mesenteric lymph node, colon, and brain specimens were collected for histologic evaluation. RESULTS: Kids developed mild-to-moderate clinical respiratory tract infection. Virus was recovered consistently from nasal secretion and sporadically from fecal specimens. Grossly, there were multiple areas of atelectasis and hyperemia, principally in the cranioventral portion of the lungs. Microscopically, there was detachment and sloughing of foci of epithelial cells of the terminal bronchioles and alveoli. In kids necropsied late in the disease, these changes were accompanied by hyperplasia of type-II epithelial cells. Viral inclusions were not an obvious feature, but a few cells contained probable inclusions. CONCLUSIONS AND CLINICAL RELEVANCE: The caprine adenovirus reported here is capable of inducing respiratory tract disease and lesions in the lungs of young kids.

Adenoviridae↗
PubMed1996

Improvements in a competition assay to detect scrapie prion protein by capillary electrophoresis.

Scrapie in sheep and goats is the prototype of transmissible spongiform encephalopathies found in humans and animals. A feature of these diseases is the accumulation of rod-shaped fibrils in the brain that form from an aggregated protein. This protein is a protease-resistant form of a normal host cell protein. When the aggregated protein is denatured in SDS and beta-mercaptoethanol, a monomer form (prion protein) with a molecular mass of 27 kDa is observed. Free zone capillary electrophoresis and peptides labeled with fluorescein were used to detect the prion protein through competition for a labeled peptide in immune complex formation. The separation of the immune complexes from the unbound peptide using 200 mM Tricine (pH 8.0) was faster and was better resolved than that obtained with phosphate or borate buffer systems. The amount of immune complex formation was dependent on the amount of antibody in the assay. The amount of bound labeled peptide and unbound labeled peptide could be measured directly by calculating the area of each respective peak. As increasing amounts of unlabeled peptide were added to the assay, a concentration dependent reduction in the immune complex peak was observed. The assay could detect less than 10.0 fmol of unlabeled peptide. There was a quantitative difference in the competition of preparations from scrapie infected sheep brain and normal sheep brain.

Animals↗
PubMed1996

Lesions in lambs experimentally infected with ovine adenovirus serotype 6 and Pasteurella haemolytica.

Twenty-five colostrum-deprived lambs reared in isolation were inoculated with a US variant of ovine adenovirus serotype 6 (OAV-6) strain RTS-151, Pasteurella haemolytica, or a combination of the 2 agents. Although severe pulmonary lesions were caused by each agent, the lesions were more severe and lasted longer with the combined infection. Lesions induced by OAV-6 alone developed 6-9 days after inoculation and lasted for 15 days, the length of the experiment. The lesions were characterized by suppurative inflammation at the junction of the terminal bronchioles and alveoli. Air spaces were filled with neutrophils and sloughed epithelial cells, which often contained large intranuclear inclusions. Lesions induced by P. haemolytica alone developed within 1 day and persisted for no more than 10 days and were characterized by severe pulmonary edema with variable amounts of fibrin. Lesions induced by the combined infection had aspects of each infection alone and resulted in severe disease in 4 of 8 lambs that were permitted to live more than 1 day after inoculation with bacteria. Early pulmonary lesions included edema, limited fibrin deposition, and slight purulent bronchiolitis and alveolitis. Later lesions included necrosis and more fibrin. For lambs inoculated with both pathogens, resolution was incomplete 15 days after inoculation of virus (10 days after inoculation of P. haemolytica). The results presented here corroborate previous findings indicating that the RTS-151 variant of OAV-6 is common in lambs and acts in concert with P. haemolytica to cause severe and often fatal pneumonia.

Adenoviridae Infections↗
PubMed1996

In vitro lymphocyte proliferative responses and gamma-interferon production as measures of cell-mediated immunity of cattle exposed to Pasteurella haemolytica.

Cell-mediated immune mechanisms may play a role in the pathogenesis and prevention of pneumonia in cattle caused by Pasteurella haemolytica serotype A1. To determine the circumstances required to stimulate and identify cell-mediated immune responses, calves were vaccinated with a commercial P. haemolytica bacterin or a live commercial P. haemolytica vaccine, or were infected intratracheally with virulent P. haemolytica. All calves were challenge-exposed intratracheally with P. haemolytica 31 d after vaccination or prior infection. Peripheral blood mononuclear cells and mediastinal and superficial cervical lymph node cells were stimulated with antigens prepared from P. haemolytica to evaluate in vitro proliferative responses and gamma-interferon production as measures of cell-mediated immunity. Strong proliferative responses and gamma-interferon production were detected in lymph node cells from calves vaccinated with the live vaccine and from infected calves, especially in response to stimulation with an outer membrane protein preparation from P. haemolytica. Greater proliferative responses and gamma-interferon production were associated with the lymph node nearer the site of bacterin administration (superficial cervical lymph node) or the site of infection (mediastinal lymph node), whereas greater proliferative responses and gamma-interferon production were associated with the more distant lymph node (mediastinal lymph node) in calves vaccinated with the live vaccine. Neither proliferative responses nor gamma-interferon production were detected in peripheral blood mononuclear cells from calves that were vaccinated for or infected with P. haemolytica. Antileukotoxin antibody titers were determined by a serum neutralization assay, and protection against pneumonic lesions was more closely correlated with antileukotoxin antibody responses than with lymphocyte proliferation or gamma-interferon responses.

Animals↗
PubMed1994

Capillary electrophoresis of the scrapie prion protein from sheep brain.

Scrapie in sheep and goats causes a progressive, degenerative disease of the central nervous system and is the prototype of other transmissible spongiform encephalopathies (TSE) found in humans and in animals. In samples of TSE-affected brains, unique rod-shaped structures are found and are infectious. These rods are composed of a protease-resistant, post-translationally modified cellular protein (PrPsc) that has a molecular mass of ca. 27,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Laboratory tests used for the diagnosis of scrapie detect PrPsc. The overall concentration of PrPsc in tissues is low. The present methods to diagnose scrapie are lengthy, require relatively large quantities of starting material to detect PrPsc and lack sensitivity. We explored the use of free zone capillary electrophoresis and immunocomplex formation to detect PrPsc in the brain tissue of infected sheep. Brain tissue from both infected (as confirmed by histological and biological tests) and from normal animals was used to prepare the PrPsc. After treatment with proteinase K and non-ionic detergents, PrPsc was solubilized and reacted with a rabbit antiserum specific for a peptide of the prion protein. Immunocomplex formation was observed for the samples from scrapie-infected brain but not for samples from normal brain. When a fluorescein-labeled goat anti-rabbit immunoglobulin was used as a second antibody, the detection of immunocomplex formation was enhanced both by the immunological technique and by using laser-induced fluorescence for detection. This same rabbit antiserum was used on immunoblot analysis. Three bands were observed for material from an infected sheep but none in preparations from brain material from normal sheep.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Intracerebral transmission of scrapie to cattle.

To determine if sheep scrapie agent(s) in the United States would induce a disease in cattle resembling bovine spongiform encephalopathy, 18 newborn calves were inoculated intracerebrally with a pooled suspension of brain from 9 sheep with scrapie. Half of the calves were euthanatized 1 year after inoculation. All calves kept longer than 1 year became severely lethargic and demonstrated clinical signs of motor neuron dysfunction that were manifest as progressive stiffness, posterior paresis, general weakness, and permanent recumbency. The incubation period was 14-18 months, and the clinical course was 1-5 months. The brain from each calf was examined for lesions and for protease-resistant prion protein. Lesions were subtle, but a disease-specific isoform of the prion protein was present in the brain of all calves. Neither signs nor lesions were characteristic of those for bovine spongiform encephalopathy.

Animals↗
PubMed1994

Infected cell types in ovine lung following exposure to bovine respiratory syncytial virus.

Sixteen adult sheep (ten females, six males obtained from a closed flock at National Animal Disease Center, Ames, IA) were experimentally infected with bovine respiratory syncytial virus strain 375 (BRSV), and lung tissues were stained for viral antigen. Two infected sheep were euthanatized at each of the following post-inoculation times: 12, 24, 36, 48, 72, 96, 144, and 192 hours. Lung, nasal turbinates, trachea, right cranial bronchial and mediastinal lymph nodes, liver, and spleen were collected for histologic evaluation. An indirect immunoperoxidase technique was performed on routine paraffin-embedded sections of lung tissue, trachea, turbinates, and bronchial and mediastinal lymph nodes to determine the location of the BRSV antigen. For lung tissue from each sheep 400 light microscopic fields at 160x magnification were examined for staining for BRSV antigen. Lung tissue was also collected for virus and bacterial isolation. Daily serum samples were taken for determination of anti-BRSV titers. Severe respiratory disease was not produced in any sheep. Bovine respiratory syncytial virus was isolated from lung tissue collected from all sheep up through 144 hours post-inoculation. At 12 hours post-inoculation (case No. 2) respiratory syncytial virus antigen was detected in bronchiolar epithelium and a mononuclear cell within an alveolar space. Lung tissue from the sheep necropsied between 24 and 144 hours post-inoculation (case Nos. 3-14) contained BRSV antigen in bronchiolar epithelium, type I pneumocytes, type II pneumocytes, alveolar macrophages, and mononuclear cells within alveolar spaces. Macrophages staining for viral antigen were rare. Bronchiolar and type I epithelial cells comprised the majority of infected cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Evaluation of an ELISA for detection of ovine progressive pneumonia antibodies using a recombinant transmembrane envelope protein.

An enzyme-linked immunosorbent assay (ELISA) was developed using a recombinant protein corresponding to the N'-terminal hydrophilic region of transmembrane glycoprotein (TM) of ovine lentivirus. This assay reproducibly detected antibodies in sera from 207 of 212 ovine progressive pneumonia (OPP) virus-infected sheep, and the recombinant TM ELISA accurately identified 26% (35 vs. 9) more seropositive samples than did the agar gel immunodiffusion test when applied to 100 sera from an infected flock. This assay also yielded no false-positive results in 14 true negative sera. Results of these experiments were further confirmed by the recombinant TM and recombinant p25 Western blot assay. A single recombinant TM antigen, as the coating antigen in ELISA, can be used successfully for the detection of OPP virus-infected animals and can improve the sensitivity and specificity for OPP diagnosis.

Animals↗
PubMed1993

Cilia-associated respiratory bacillus in wild rats in central Iowa.

Twenty-eight wild rats were live-trapped in central Iowa (USA) to estimate the prevalence of the cilia-associated respiratory (CAR) bacillus. Both light and electron microscopy were used to look for the Gram-negative, filamentous bacterium among cilia in tracheal and lung tissue sections. The organism was observed in the trachea of 20 rats with chronic respiratory disease and in the trachea of three of eight normal rats. Therefore, the organism appears to be common among wild rats in central Iowa.

Animals↗
PubMed1993

Retrospective study of diseases in a captive Lemming Colony.

Fifty-four ill or nonproductive lemmings (Dicrostonyx spp.) were evaluated for signs, lesions and causes of disease for 5 yr in a domestic colony. Parasitic granulomas caused by Encephalitozoon cuniculi were the most common finding and were seen in 22 lemmings. The disease was characterized by circling and torticollis with granulomas in many tissues, especially the central nervous system. Suppurative otitis occurred in 12 lemmings and was associated with Klebsiella pneumonia infection; circling was the common sign. Hepatic microabscesses were present in seven lemmings but a cause was not identified. Five lemmings had neoplasms and 14 had either suppurative processes, aspermia, or ovarian cysts.

Animals↗
PubMed1993

Seroepidemiologic survey for adenovirus infection in lambs.

A serologic survey was conducted to determine the prevalence and seroconversion rates for ovine adenovirus (OAV) serotypes 1-4 and bovine adenovirus (BAV) serotypes 2, 3, and 7 in sheep in Iowa and in surrounding states. For 2 consecutive years, paired serum samples were obtained from 1- to 2-month-old lambs as they entered a ram test station and, again, 2 months later. Sera were tested for adenovirus antibodies by use of a microtitration serum virus-neutralization test. At the time of entry, high prevalence of antibody (titer > or = 2) was detected to all tested adenoviruses except BAV-3. All adenoviruses were active in the ram test station both years, as indicated by > or = fourfold increase in adenovirus antibody titer (seroconversion) in some of the lambs. The prevalence and seroconversion rate for OAV-1 was 94.0 and 7.2%, respectively; for OAV-2, 98.6 and 15.1%; for OAV-3, 86.5 and 11.0%; for OAV-4, 98.4 and 13.2%; for BAV-2, 97.6 and 22.4%; for BAV-3, 11.4 and 3.8%; and for BAV-7, 81.6 and 4.5%. The results indicate that adenovirus infections were widespread in the sheep population and that the prevalence of active infection based on seroconversion rates was approximately 45%.

Adenoviridae Infections↗
PubMed1992

Prevalence of antibody to caprine arthritis-encephalitis virus in goats in the United States.

Goats from 28 states were tested for antibodies to caprine arthritis-encephalitis virus. Of 3,790 goats, 1,175 (31%) tested positive, and of 196 herds tested, 143 (73%) had 1 or more seropositive members. This prevalence, based on serum samples from all goats in the participating herds, was lower than most rates reported in other studies. Such studies were based on fewer samples, incomplete sampling of herds, or smaller geographic base. Prevalence was highest in western Pacific and northern plains regions, increased with age to 3 years, was highest among goats on family-owned farms, and was lowest in the Angora breed. Differences in prevalence was not related to gender or size of herd.

Animals↗
PubMed1992

Seroprevalence of ovine progressive pneumonia virus in sheep in the United States as assessed by analyses of voluntarily submitted samples.

Ovine progressive pneumonia (OPP) is a lentivirus-induced disease of sheep in the United States that is similar, if not identical, to maedi/visna in many other countries. Prevalence estimates of seropositivity to this virus in sheep in the United States have been confined to limited groups or flocks of sheep and have varied from 1 to 90%. In this study of detection of antibodies against OPP virus, we found a lower general prevalence of antibodies to OPP virus in sheep than was previously reported. Of 16,827 sheep from 29 states in the United States, 26% were seropositive and 48% of 164 flocks that were tested had 1 or more seropositive sheep. Seropositivity to OPP virus for sheep within special categories was determined, although nonrandom samples that were available may have biased the results. Within regions of the United States, prevalence was highest in the Rocky Mountain region at 49% and lowest in the northern Atlantic region at 9%. Seropositive sheep were not evenly distributed among flocks, but were clustered in a few flocks of sheep. A high number of flocks had no or few seropositive sheep. Prevalence increased with age from 4% at less than 1 year to a plateau of 34% at 4 years. Seropositivity was variable among breeds and was not associated with sex, wool class, or place of origin of ancestors.

Age Factors↗
PubMed1991

Seroprevalence of ovine progressive pneumonia virus in various domestic and wild animal species, and species susceptibility to the virus.

Ovine progressive pneumonia is caused by a lentivirus of known infectivity only for sheep and goats. Virus susceptibility of 11 other species of animals was examined. Species included cattle, chickens, deer, dogs, goats, hamsters, horses, mice, pigs, rabbits, and rats. Of these species, only goats and rabbits could be experimentally infected with the virus. The infection in rabbits was acute, and virus did not persist or induce antibody production as it does in sheep and goats. Sera obtained from several people working in close contact with the virus and from several wild species, with unknown exposure history, were tested for antibodies to viral antigens. All results were negative. Knowledge of the host range of this virus is important for scientific studies and for virus eradication programs.

Animals↗
PubMed1990

Survey for antibodies against maedi-visna in sheep in Poland.

Eighteen flocks of sheep were serologically tested for antibody to maedi-visna virus. A total of 4284 serum samples were tested by agar gel diffusion test and 1015 (24%) were found positive. Prevalence of infection increased with the age of sheep. Within age groups, the lowest prevalence was in the group at 1 year or less (7%) and gradually increased to the highest prevalence at 5 years of older (52%). A difference in prevalence of infection among breeds and sexes was seen but not proven because of inadequate numbers. All flocks tested were infected with a range of serological prevalence from 1.2% to 45.9%.

Age Factors↗