PubMed Health⌕ Search

Biomedical subjects

K A Brogden

Publications and source records attributed to K A Brogden.

At least 37 records · Page 2Linked to original sources
PubMed1999

Differences in the concentrations of small, anionic, antimicrobial peptides in bronchoalveolar lavage fluid and in respiratory epithelia of patients with and without cystic fibrosis.

Affinity-purified rabbit polyclonal (PAB96-1) and mouse monoclonal (1G9-1C2) antibodies to synthetic H-DDDDDDD-OH, an antimicrobial anionic peptide (AP) originally isolated from ovine pulmonary surfactant, were prepared and used to assess the concentrations of AP-like molecules in human respiratory tract samples. In bronchoalveolar lavage fluids, concentrations of AP-like molecules measured by enzyme-linked immunosorbent assay were significantly lower in 13 patients with cystic fibrosis (CF) (mean +/- standard deviation [SD], 0.78 +/- 0.46 mM) than in 34 patients without CF (1. 30 +/- 0.66 mM) (P = 0.01). In pulmonary tissues of three patients without CF, very little antigen was stained in the apical cytoplasm of the bronchial and bronchiolar epithelium yet robust staining was seen in the alveolar epithelium. In pulmonary tissues of three patients with CF, robust staining of antigen was seen in the apical cytoplasm of the bronchial and bronchiolar epithelium yet no staining was seen in the alveolar epithelium. These results show that AP-like molecules are present in healthy human respiratory tract samples and differ in concentration and location of expression in patients with and without CF.

Animals↗
PubMed1999

In situ expression of intercellular adhesion molecule-1 (ICAM-1) mRNA in calves with acute Pasteurella haemolytica pneumonia.

The in situ expression of intercellular adhesion molecule-1 (ICAM-1) mRNA in normal and pneumonic lung tissues of Holstein calves with bovine leukocyte adhesion deficiency (BLAD) was compared with that of age-matched non-BLAD Holstein calves by in situ hybridization. Twenty-four Holstein calves (both BLAD and non-BLAD) were randomly assigned to one of two experimental groups and inoculated intrabronchially with Pasteurella haemolytica or pyrogen-free saline. Lung tissues were collected and fixed in 10% neutral formalin at 2 or 4 hours postinoculation (PI). The expression and distribution of ICAM-1 mRNA in the different cell types of the lung tissue was detected by in situ hybridization with a 307-base-pair bovine ICAM-1 riboprobe. In lungs of both non-BLAD and BLAD saline-inoculated calves, ICAM-1 expression was present in epithelial cells but occurred in <30% of cells in bronchi, bronchioles, and alveoli. ICAM-1 expression in vascular endothelial cells was present in <30% of cells in pulmonary arteries and veins. The expression of ICAM-1 was significantly greater (>60% of cells) in bronchiolar and alveolar epithelial cells and pulmonary endothelial cells of arteries and veins in both BLAD and non-BLAD calves inoculated with P. haemolytica. Bronchiolar epithelium had the highest intensity of mRNA expression and highest percentage of cells that were stained, whereas bronchial epithelium had the lowest intensity and percentage of cells stained. Most alveolar macrophages and neutrophils in infected lungs also expressed ICAM-1. ICAM-1 expression was generally increased in infected BLAD calves at 2 hours PI as compared with non-BLAD calves but not at 4 hours PI. The increased expression of ICAM-1 during acute P. haemolytica pneumonia in calves suggests that ICAM-1 is upregulated and may play a role in leukocyte infiltration. The extent of ICAM-1 expression in P. haemolytica-inoculated calves with BLAD was initially enhanced but otherwise similar to that in non-BLAD calves.

Animals↗
PubMed1998

Changes in the lungs of lambs after intratracheal injection of lipopolysaccharide from Pasteurella haemolytica A1.

Ten lambs aged 8 weeks were inoculated intratracheally through the tracheal wall with lipopolysaccharide from Pasteurella haemolytica A1 and examined in chronological sequence by light and electron microscopy for pulmonary lesions. An acute fibrinopurulent pneumonia was produced, which resolved within 72 h but bore many resemblances to field cases of pneumonic pasteurellosis. Sequestration of neutrophils in the capillaries of the lungs and aggregation of surfactant in the alveoli occurred rapidly, followed by swelling of the alveolar and capillary endothelia, oedema, haemorrhage, and emigration of neutrophils into the interstitium and small air spaces of the lungs. Necrosis of isolated neutrophils was a constant feature. Alveolar, interstitial and intravascular macrophages and lymphoid cells increased slowly to become the predominant inflammatory cells at 72 h. A surprising feature was the transient appearance of multinucleated cells in the lungs at 2 and 6 h after inoculation. It is concluded that lipopolysaccharide makes a major contribution to the pathogenesis of P. haemolytica infection in the lungs of sheep.

Animals↗
PubMed1998

Detection of anionic antimicrobial peptides in ovine bronchoalveolar lavage fluid and respiratory epithelium.

Three small antimicrobial anionic peptides (AP) were originally isolated from an ovine pulmonary surfactant. However, their presence in bronchoalveolar lavage (BAL) fluid and tissues of the respiratory tract is unknown. In this study, we made affinity-purified rabbit polyclonal and mouse monoclonal antibodies to synthetic H-DDDDDDD-OH. Antibody specificity was assessed by a competitive enzyme-linked immunosorbent assay (ELISA), and the exact epitope binding sites were determined with analog peptides synthesized on derivatized cellulose. These antibodies were used to detect AP in BAL fluid by ELISA and in respiratory tissues by Western blot analysis and immunocytochemistry. BAL fluid from 25 sheep contained 0.83 +/- 0.33 mM AP (mean +/- standard deviation; range, 0.10 to 1.59 mM) and was antimicrobial. The presence of AP in BAL fluid was confirmed by reverse-phase high-pressure liquid chromatography fractionation followed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry on those fractions which were positive by competitive ELISA and demonstrated antimicrobial activity. In Western blots, polyclonal antibody PAB96-1 and monoclonal antibody 1G9-1C2 (5.0 micrograms/ml) detected four bands in solubilized turbinate and tracheal epithelial cells (53.7, 31.2, 28.0, and 25.7 kDa) and five bands in lung homogenates (53.5, 37.1, 31.2, 28.0, and 25.7 kDa). Only a single band was seen in solubilized liver and small-intestine homogenates, and no bands were seen in blots containing BAL fluid, albumin, or kidney or spleen homogenates. In pulmonary-tissue sections, both antibodies PAB96-1 and 1G9-1C2 identified accumulated protein in the apical cytoplasm of the bronchial and bronchiolar epithelia, in the cytoplasm of pulmonary endothelial cells, and in an occasional alveolar macrophage. As a first step in identifying a candidate AP precursor gene(s), degenerate oligonucleotides representing all possible coding combinations for H-GADDDDD-OH and H-DDDDDDD-OH were synthesized and used to probe Southern blots of sheep genomic DNA. Following low-stringency washes and a 2-day exposure, strongly hybridizing bands could be identified. One degenerate oligonucleotide, SH87, was used as a hybridization probe to screen a sheep phage genomic library. Two independent phage contained the H-GADDDDD-OH coding sequence as part of a larger predicted protein. AP may originate as part of an intracellular precursor protein, with multistep processing leading to the release of the heptapeptide into mucosal secretions. There it may interact with other innate pulmonary defenses to prevent microbial infection.

Amino Acid Sequence↗
PubMed1998

The incidence of caseous lymphadenitis in Alberta sheep and assessment of impact by vaccination with commercial and experimental vaccines.

In Alberta, caseous lymphadenitis (CLA) is one of the leading causes of lamb and mutton carcass condemnation. In this study, serologic results confirmed a high (50-94%) incidence of exposure to Corynebacterium pseudotuberculosis, the causative agent of CLA, in mature, unvaccinated sheep in southern Alberta. To assess the efficacy and impact of vaccination with 2 commercial (Glanvac-6 and Case-Vac) and 1 experimental (WC+ MDP-GDP) CLA vaccines, a series of 3 field trials in 3249 ewes and lambs was conducted in affected flocks from 1992-1996. Efficacy was assessed from the serological response to vaccination, prevalence and size of injection site reactions by treatment, and the incidence of CLA abscesses. Overall, agglutinating antibody titres to C. pseudotuberculosis in lambs vaccinated with WC+MDP-GDP and Case-Vac remained significantly elevated above nonvaccinated control lambs for the 12 mo period after the initial vaccination. Lambs vaccinated with the WC/MDP-GDP maintained higher titres (P < 0.06) than those vaccinated with Case-Vac for the period from 6 to 12 mo after vaccination. Agglutinating antibody titres for lambs vaccinated with Glanvac did not differ from those of controls at any point during the 12 mo period after vaccination. The number of injection site reactions was elevated in lambs vaccinated with Glanvac as compared to those vaccinated with WC+MDP-GDP but the size of injection site reactions did not significantly differ. Sheep vaccinated with WC+ MDP-GDP also had a reduced incidence of putative CLA abscesses, although confirmation of the presence of C. pseudotuberculosis was only successful in a small number of instances.

Abscess↗
PubMed1997

Influence of immunization on the pulmonary inflammatory response of rabbits induced by Pasteurella haemolytica A1 lipopolysaccharide.

Immune complex formation has long been thought to play a role in the pathogenesis of Pasteurella haemolytica pneumonia. This study in laboratory rabbits was designed to investigate immune-mediated damage in respiratory tissue caused by lipopolysaccharide (LPS). Severe lesions were induced by the intratracheal (IT) injection of P. haemolytica A1 LPS (50 micrograms) into rabbits previously immunized with P. haemolytica killed whole cells emulsified with Freund's incomplete adjuvant (FIA); these lesions included perivascular oedema and polymorphonuclear leucocyte (PMN) infiltration of the subintima, with degeneration and necrosis of the media. Smaller vessels were occluded by PMNs in various stages of degranulation. PMN counts in bronchoalveolar lavage (BAL) fluid were significantly elevated (P < 0.05). Lesions were also induced by the IT injection of LPS (50 micrograms) into rabbits pretreated with an emulsion consisting merely of FIA and formol-saline; these lesions included moderate to severe congestion, interstitial oedema, alveolar serofibrinous exudation and PMN infiltration. PMNs were also present in BAL fluid. Rabbits pretreated with FIA in formol-saline and given a later IT injection of saline, and rabbits pretreated with bovine serum albumin (BSA) in FIA and given a later IT injection of BSA, were included as negative and positive control groups. Cutaneous lesions were also induced by the intradermal injection of LPS into rabbits immunized against P. haemolytica and of BSA into rabbits immunized with BSA. Overall, the pulmonary and cutaneous lesions induced in vaccinated rabbits by antigen administration were more severe than those seen in non-vaccinated rabbits. The lesions in rabbits, which were similar to those seen in natural cases of P. haemolytica pneumonia in cattle, were characterized by a fibrinopurulent inflammatory process with extensive interstitial oedema, fibrinous exudate, and PMNs. This model may help to elucidate the pathogenesis of pneumonic pasteurellosis in immunized animals.

Analysis of Variance↗
PubMed1997

Small, anionic, and charge-neutralizing propeptide fragments of zymogens are antimicrobial.

Some inactive precursor proteins, or zymogens, contain small, amino terminus, homopolymeric regions of Asp that neutralize the cationic charge of the active protein during synthesis. After posttranslational cleavage, the anionic propeptide fragment may exhibit antimicrobial activity. To demonstrate this, ovine trypsinogen activation peptide, and frog (Xenopus laevis) PYL activation peptide, both containing homopolymeric regions of Asp, were synthesized and tested against previously described surfactant-associated anionic peptide. Peptides inhibited the growth of both gram-negative (MIC, 0.08 to 3.00 mM) and gram-positive (MIC, 0.94 to 2.67 mM) bacteria. Small, anionic, and charge-neutralizing propeptide fragments of zymogens form a new class of host-derived antimicrobial peptides important in innate defense.

Anions↗
PubMed1996

Isolation of an ovine pulmonary surfactant-associated anionic peptide bactericidal for Pasteurella haemolytica.

Ovine pulmonary surfactant is bactericidal for Pasteurella haemolytica when surfactant and bacteria mixtures are incubated with normal ovine serum. To isolate this component, surfactant (1 mg/ml) was centrifuged at 100,000 x gav, and the supernatant was fractionated by HPLC. Fractions were eluted with acetonitrile (10-100%)/0.1% trifluoracetic acid and tested for bactericidal activity. Amino acid and sequence analysis of three bactericidal fractions showed that fraction 2 contained H-GDDDDDD-OH, fraction 3 contained H-DDDDDDD-OH, and fraction 6 contained H-GADDDDD-OH. Peptides in 0.14 M NaCl/10 microM ZnCl2 (zinc saline solution) induced killing of P. haemolytica and other bacteria comparable to defensins and beta-defensins [minimal bactericidal concentration (MBC)50 range, 0.01-0.06 mM] but not in 0.14 M NaCl/10 mM sodium phosphate buffer, pH 7.2/0.5 mM CaCl2/0.15 mM MgCl2 (MBC50 range, 2.8-11.5 mM). Bactericidal activity resided in the core aspartate hexapeptide homopolymeric region, and MBC50 values of aspartate dipeptide-to-heptapeptide homopolymers were inversely proportional to the number of aspartate residues in the peptide. P. haemolytica incubated with H-DDDDDD-OH in zinc saline solution was killed within 30 min. Ultrastructurally, cells contained flocculated intracellular constituents. In contrast to cationic defensins and beta-defensins, surfactant-associated anionic peptides are smaller in size, opposite in charge, and are bactericidal in zinc saline solution. They are members of another class of peptide antibiotics containing aspartate, which when present in pulmonary secretions may help clear bacteria as a part of the innate pulmonary defense system.

Amino Acid Sequence↗
PubMed1996

Passage of CD18- and CD18+ bovine neutrophils into pulmonary alveoli during acute Pasteurella haemolytica pneumonia.

CD18 is a subunit for three beta 2 integrin molecules (Mac-1, p150, 95, LFA-1), which are expressed on the plasma membrane of neutrophils. These molecules mediate passage of neutrophils into sites of infection. In children and animals that lack CD18 expression, neutrophil infiltration is impaired in most tissues. However, in lung, CD18- neutrophils have been identified in the airway spaces during spontaneous episodes of pneumonia. To determine whether CD18 is vital for passage through the pulmonary alveolar wall, lung lobes of cattle with neutrophils that were deficient in CD18 expression (CD18-) and cattle with normal CD18 expression (CD18+) were inoculated with Pasteurella haemolytica by fiberoptic bronchoscopy; control lobes were inoculated with pyrogen-free saline (PFS). Neutrophil passage into alveolar lumina at 4 and 6 hours postinoculation was measured by computerized image analysis. Blood levels of neutrophils for CD18- cattle ranged from 12- to 26-fold higher than for CD18+ cattle prior to inoculation, and counts in both groups rose slightly postinoculation. In P. haemolytica-inoculated lobes, total numbers of neutrophils in alveolar lumina of the two groups were similar. An increase in the number of neutrophils in the alveolar wall was fourfold greater in CD18- cattle than in CD18+ cattle. In PFS-inoculated lobes, the number of neutrophils in the alveolar wall was sixfold higher in CD18 cattle than in CD18+ cattle. This work shows that by 4 and 6 hours, CD18- neutrophils enter the alveolar lumen at a rate similar to that in CD18+ cattle. Higher numbers of CD18- neutrophils are present in the alveolar wall of control (PFS) and bacteria-inoculated lobes. Thus, the CD18- cells are increased in the walls of alveoli and numbers of neutrophils that enter the alveolar lumen are similar in CD18+ and CD18- cattle.

Acute Disease↗
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↗
PubMed1995

Binding between lipopolysaccharide and cecropin A.

Cecropin A (CA), a bioactive peptide, produced significant lethality to Pantoea agglomerans (PA) at low concentrations. Significant mortality occurred immediately after addition of CA. Separate preincubations of lipopolysaccharides (LPS) from the following bacteria: PA, Serratia marcescens, Escherichia coli (EC), and Salmonella typhimurium with CA were performed prior to the bioassay. CA was also preincubated with diphosphoryl lipid A (DPL-A) from EC and S. minnesota (SM), trilinolein, palmitic, lauric and myristic acids (fatty acids contained in the lipid A of PA-LPS) and bovine brain gangliosides. Spectral analysis to determine the interaction between glycosphingolipids (sphingomyelin, bovine brain gangliosides, and galactocerebrosides) and CA were performed. Results showed that all types of LPS and DPL-A as well as gangliosides studied blocked CA lethality to PA. The level of inhibition of CA antibacterial properties was dependent on LPS and DPL-A concentration. The individual fatty acids and trilinolein did not affect CA lethality to PA. Spectral studies showed complexation between CA and PA-LPS, both types of DPL-A, and the glycosphingolipids. Biological and chemical analyses confirm that CA binds to the diphosphoryl lipid A moiety of LPS.

Animals↗
PubMed1995

Protection of ruminants by Pasteurella haemolytica A1 capsular polysaccharide vaccines containing muramyl dipeptide analogs.

The capsular polysaccharide (CP) of Pasteurella haemolytica serotype A1 is a poor immunogen for the prevention of pneumonic pasteurellosis of ruminants. To improve CP immunogenicity, vaccines were prepared with 1.0 mg CP dose-1 with and without the synthetic adjuvant, muramyl dipeptide (MDP; range 0.2-1.0 mg) or a lipophilic derivative, MDP-sn-glyceryl-dipalmitoyl (MDP-GDP; range 0.1-1.0 mg). The optimum effective concentration of adjuvant was first determined in lambs and calves and then the efficacy of CP +0.5 mg MDP and CP +1.0 mg MDP-GDP was compared with that of two commercial vaccines in calves. After immunization with CP, antibody titers in lambs and calves were typical of that seen with polysaccharide immunogens and characterized by an early IgM response followed by later IgG1 and IgG2 responses. CP + MDP or MDP-GDP vaccines induced significantly higher IgM, IgG1, and IgG2 titers. After transtracheal challenge of immunity with P. haemolytica serotype A1, extensive pulmonary consolidation containing P. haemolytica (10(6)-10(8) c.f.u. g-1) was seen in all lambs and calves vaccinated with CP alone and was not significantly different (P < 0.05) from the consolidation and concentrations of organisms in nonvaccinated challenge controls. In lambs, vaccines containing 1.0 mg CP +0.05 mg MDP or MDP-GDP significantly reduced pulmonary consolidation and concentrations of P. haemolytica in lung lesions. In calves, vaccines containing 0.2 mg MDP, 0.5 mg MDP, or 1.0 mg MDP-GDP also significantly reduced pulmonary consolidation and concentrations of P. haemolytica in lung lesions. Vaccines containing CP +0.5 mg MDP and CP +1.0 mg MDP-GDP induced high titer bactericidal antibodies by 7 days and were more efficacious than two commercial vaccines. Potentiation of CP with MDP or MDP-GDP has great promise in furthering the potential of CP as a vaccine immunogen for the prevention of pneumonic pasteurellosis.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1995

Pasteurella haemolytica lipopolysaccharide-associated protein induces pulmonary inflammation after bronchoscopic deposition in calves and sheep.

The lipopolysaccharide (LPS)-associated protein (LAP) was extracted from Pasteurella haemolytica serotype A1 strains L101 (bovine origin) and 82-25 (ovine origin). Extracts contained 0.017% total LPS and appeared as only two bands at 14 and 16.6 kDa after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. To determine the extent of pulmonary inflammation induced by LAP and its possible role in the pathogenesis of pneumonic pasteurellosis, LAP (500 micrograms in pyrogen-free saline [PFS]) was deposited by fiber-optic bronchoscopy into the dorsum of the caudal portion of the cranial lobe of the right lung of calves (strain L101 LAP) and sheep (strain 82-25 LAP). LPS (500 micrograms in PFS), 3-h P. haemolytica cultures (1.6 x 10(8) to 1.9 x 10(8) CFU in PFS), and PFS alone were deposited similarly as controls. At necropsy, 24 h after deposition, gross and histologic pulmonary lesions of calves and sheep given LAP, LPS, and P. haemolytica were similar and consisted of various degrees of acute bronchopneumonia (relative severities of lesions induced: LAP < LPS < live organisms). By subjective histologic interpretation and semiquantitative morphometry, animals given LAP had the highest percentage of macrophages per alveolar lumen and the lowest percentage of neutrophils. The lesions from animals given LPS were more severe than those given LAP, but the morphometric cell counts were similar. In contrast, animals inoculated with P. haemolytica had lesions typical of this agent, consisting of many neutrophils, proteinaceous exudate, and a few macrophages. Morphometrically, these lesions had the highest numbers of neutrophils and the lowest numbers of macrophages. These studies show that LAP can induce an inflammatory response in the alveolar lumens and may play a role in the pathogenesis of pneumonic pasteurellosis.

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

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↗