bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Fecal Sample Weight on Detection of Salmonella Enterica in Swine Feces
Authors: Funk Julie A. , Davies Peter R. , Nichols Monica A.
Published: May 2011

The effect of different fecal sample weights on the detection of Salmonella enterica in swine feces was examined. Sample weights evaluated were rectal swabs and fecal samples weighing 1 g, 10 g, and 25 g. Comparisons were made on matched fecal samples obtained from individual pigs housed on 2 commercial swine farms in North Carolina. Relative sensitivity (number of positive pigs per fecal weight category/number positive in all weight categories) increased ( P < 0.001) with fecal sample weight, and ranged from 9% for rectal swabs to 78% for 25-g samples. Stomaching of fecal samples did not affect detection of S. enterica. These observations demonstrate that fecal sample weight can markedly influence estimates of prevalence of S. enterica in epidemiologic studies. Failure to consider the imperfect sensitivity of bacterial culture in the design and interpretation of epidemiologic studies will lead to underestimation of prevalence and reduced power to detect the presence of S. enterica-infected herds.
Coxiella Burnetii Infection is Associated with Placentitis in Cases of Bovine Abortion
Authors: Bildfell Robert J. , Thomson Gary W. , Haines Deborah M. , McEwen Beverly J. , Smart Nonie
Published: May 2011

A positive score on a modified acid-fast (MAF)-stained smear test of fresh placenta was used to identify a group of bovine abortion submissions believed to be infected with Coxiella burnetii. Immunohistochemical (IHC) testing for Coxiella and Chlamydia antigens was performed on 14 MAF smear-positive cases as well as 29 MAF smear-negative cases Received during the study period. Nine MAF smear-positive cases as well as 1 MAF smear-negative case were Coxiella-positive via the IHC test. No placentas were positive for Chlamydia antigen. Various histopathologic features were categorized for all placentas and the presence or absence of selected risk categories was also graded for each case. The results between Coxiella IHC-positive cases and Coxiella IHC-negative/MAF-negative cases were compared using Fisher's exact test ( P value at 95% confidence). Significant associations were found between Coxiella IHC-positive cases and the presence of placental inflammation ( P = 0.0027), placental necrosis ( P = 0.012), fetal pneumonia ( P = 0.0152), and the visibility of Coxiella-like organisms within trophoblasts on hematoxylin and eosin–stained sections ( P < 0.0001). Histopathologic features of Coxiella IHC-positive placentas included infiltration of the chorionic stroma by mononuclear cells, necrosis of chorionic trophoblasts, and focal exudation of fibrin and neutrophils. The results indicate that MAF smears are a good screening tool for the presence of Coxiella in placentas from bovine abortion cases and that the detection of this pathogen in aborted placentas via traditional staining or IHC methods is usually associated with placentitis.
Bronchoalveolar Lavage Cytology and Hematology: A Comparison between High and Low Health Status Pigs at Three Different Ages
Authors: Jolie Rika , Olson Linda , Bäckström Lennart
Published: May 2011

Bronchoalveolar lavages (BALs) were performed with a bronchoscope on 5- and 7.5-week-old, anesthetized, high health status pigs ( n = 14). At 10 weeks of age, pigs ( n = 28) were necropsied, lungs were removed, and BAL samples were collected from the right diaphragmatic lobe with a modified 12-Fr (4-mm) Foley catheter. Peripheral blood was sampled from all pigs ( n = 28) before each BAL procedure. Peripheral blood and BAL samples were collected according to a similar study design at 5, 7.5, and 10 weeks of age from 12 low health status pigs, which were raised according to standard farm procedures ( n = 6) or as segregated early weaned pigs ( n = 6). Bronchoalveolar lavage cytology and hematologic 95% confidence intervals were determined for 5-, 7.5-, and 10-week-old high (group A) and low health status pigs (groups B and C). The results were compared between the different groups. Repeated BALs were easily performed in all pigs, making this an additional tool for evaluation of respiratory health. Total numbers of cells and neutrophils in peripheral blood and BAL samples were greater in low health status pigs than in high health status pigs. Hematologic results paralleled the findings in BAL fluid. Segregated early weaning of low health status pigs in a less challenging environment mainly reduced the number of neutrophils in BAL samples and peripheral blood.
Isolation of Environmental Clostridium Difficile from a Veterinary Teaching Hospital
Authors: Weese J. Scott , Staempfli Henri R. , Prescott John F.
Published: May 2011

An environmental survey of a veterinary teaching hospital for the presence of Clostridium difficile was performed using contact plates and cycloserine-cefoxitin-fructose with 0.1% sodium taurocholate agar. Clostridium difficile was isolated from 24 of 381 sites (6.3%). Growth was obtained from 4.5% (9/202) of sites sampled in the Large Animal Clinic, from 8.1% (13/160) of sites within the Small Animal Clinic, and from 20% (2/10) of sites sampled elsewhere. Fourteen of 21 strains tested produced toxins in vitro. A geographic association was found with areas in the large animal clinic where nosocomial C. difficile diarrhea in horses had previously been diagnosed. Several other sites with a potential for nosocomial transmission of the organism were identified. Areas from which C. difficile was isolated tended to be areas with high animal traffic, with increased chance of fecal contamination, and with rough, difficult to clean surfaces. This study documents the prevalence of this organism in the environment and its potential role in nosocomial disease.
Efficacy of a Modified Polymerase Chain Reaction Assay for Detection of Ehrlichia Canis infection
Authors: Mathew John S. , Ewing Sidney A. , Malayer Jerry R. , Fox Joseph C. , Kocan Katherine M.
Published: May 2011

Detection of Ehrlichia canis in acutely infected and convalescent dogs is important for effective treatment and control. However, accurate detection has been difficult to achieve, in part because dogs that have been treated therapeutically often remain seropositive for extended periods. A new method, polymerase chain reaction (PCR) assay using biotinylated E. canis-specific primers (PCR-BP), was developed for detection of E. canis. Four dogs experimentally infected with E. canis by intravenous inoculation of whole blood from carrier dogs and 2 naturally infected convalescent carriers were used to compare the specificity and sensitivity of the new method with that of microscopy/blood smear evaluation, serologic test, and conventional PCR assay using E. canis-specific primers. In experimentally infected animals, infection was detected as early as 7 days postexposure using PCR-BP. Although the 2 naturally infected dogs were positive by serologic test and PCR-BP, both were negative by conventional PCR. Results suggest that the new method is a sensitive assay for detection of E. canis infection. In addition, results were obtained more rapidly than with other PCR-based assays.
Proliferation of Maxillary and Mandibular Periodontal Squamous Cells in Mink Fed 3,3′,4,4′,5-Pentachlorobiphenyl (PCB 126)
Authors: Render James A. , Aulerich Richard J. , Bursian Steven J. , Nachreiner Raymond F.
Published: May 2011

This report characterizes squamous cell proliferation in young farm mink ( Mustela visori) fed a diet supplemented with 0.024 ppm 3,3′,4,4′,5-pentachlorobiphenyl (polychlorinated biphenyl [PCB] congener 126). One to 2 months of dietary exposure to PCB 126 resulted in gross lesions of the upper and lower jaws consisting of mandibular and maxillary nodular proliferation of the gingiva and loose teeth. The maxilla and mandible of the PCB-treated mink were markedly porous because of loss of alveolar bone. Histologically, this osteoporosis was caused by proliferation of squamous cells that formed infiltrating cords. This report clearly documents the fact that the environmental contaminant PCB 126 can cause osteoinvasive squamous proliferation in young mink, although the dose used in the present study was 7 and 36 times higher than what is typically encountered in contaminated bird eggs and fish, respectively.
Epizootic Malignant Catarrhal Fever in Three Bison Herds: Differences from Cattle and Association with Ovine Herpesvirus-2
Authors: Schultheiss Patricia C. , Collins James K. , Spraker Terry R. , DeMartini James C.
Published: May 2011

Three bison herds in Colorado experienced high mortality from malignant catarrhal fever (MCF). In comparison with cattle, the bison had a more rapidly progressive disease, fewer clinical signs, and milder inflammatory histologic lesions. There was consistent association with ovine herpesvirus-2 (OHV-2). Contact with sheep was not consistent. Of 17 animals in herd A, 15 died of acute MCF; 1 was slaughtered while healthy; and 1 developed clinical signs of MCF, was treated with corticosteroids and antibiotics, and died of fungal abomasitis and rhinitis after 5 months. In herds B and C, approximately 300 of 900 and 18 of 20 died of MCF following brief clinical disease. The nearest sheep were 1 mile away from herd A, but direct contact with sheep could be documented in herds B and C. Complete gross and histologic examinations were conducted on 34 animals, including all animals in herd A, and MCF was diagnosed in 31. In addition, field necropsies were performed on all dead animals in herd B and most in herd C and MCF was diagnosed on the basis of the gross lesions in most animals. Clinical signs of each animal in herd A were recorded. Illness was brief, usually 8–48 hours. Clinical signs were subtle; separation from the herd was often observed. In all 3 herds, hemorrhagic cystitis and multifocal ulceration of the alimentary tract were consistently found at necropsy. Mild lymphocytic vasculitis was present in multiple organs. Ovine herpesvirus-2 was found by polymerase chain reaction (PCR) in 71 of 105 formalin-fixed tissue specimens from 29 of 31 animals with MCF. In herd A, blood samples from 13 animals were collected at 5 time points and tested by PCR for the presence of OHV-2 viral sequences in peripheral blood leukocytes. Nine bison with a positive PCR test and 4 with negative results prior to clinical illness died of MCF.
Interstitial Pneumonia in Feedlot Cattle: Concurrent Lesions and Lack of Immunohistochemical Evidence for Bovine Respiratory Syncytial Virus Infection
Authors: Sorden Steven D. , Kerr Robert W. , Janzen Eugene D.
Published: May 2011

The objectives of this study were to describe the nature and distribution of microscopic lung lesions in feedlot cattle with interstitial pneumonia and to determine whether bovine respiratory syncytial virus (BRSV) antigen was present in affected lungs. Lungs with macroscopic lesions compatible with interstitial pneumonia were collected from cattle from 5 west-central Saskatchewan feedlots that had been on feed for greater than 60 days at the time of death. Interstitial pneumonia was most consistently present in dorsal portions of caudal lung lobes and in 21/28 cases (75%) had a multifocal to coalescing distribution. All 28 lungs exhibited hyaline membrane formation and some degree of type II alveolar epithelial cell hyperplasia, consistent with an acute to subacute duration. Twenty-one of 28 cases (75%) had concurrent bronchopneumonia in at least 1 lung lobe; bronchopneumonia was grossly evident in 9/28 cases (32%). Chronic bronchitis or bronchiolitis was present in at least 1 section in 12/28 (43%) of the lungs, and 25/28 (89%) had at least 1 focus of bronchiolitis fibrosa obliterans. Bronchopneumonia and bronchiolitis fibrosa obliterans were markedly less common in 10 sets of bovine lungs obtained from an abattoir. Bovine respiratory syncytial virus antigen was demonstrated using immunohistochemistry in 2/28 cases and was associated with bronchiolar epithelial necrosis that was more severe than the bronchiolar lesions in the BRSV antigen-negative cases. Interstitial pneumonia in feedlot cattle in this study was more frequently associated with suppurative bronchopneumonia and bronchiolitis fibrosa obliterans than with BRSV infection.
Detection of Akabane Viral Antigens in Spontaneous Lymphohistiocytic Encephalomyelitis in Cattle
Authors: Uchida K. , Murakami T. , Sueyoshi M. , Tsuda T. , Inai K. , Acorda J. A. , Yamaguchi R. , Tateyama S.
Published: May 2011

A 5-month-old Japanese black bull calf and twenty-seven 1–27-day-old calves exhibiting neurological signs between August and October 1998 were examined. The bull calf exhibited rapid breathing, fever, hypersensitivity, and ataxia and was euthanized 4 days after the onset of symptoms. The 27 calves primarily exhibited ataxia, and 15 had arthrogryposis. Histological examination of the bull calf revealed perivascular infiltraction by mononuclear cells, diffuse to multifocal gliosis, and neuronal necrosis in the brain and spinal cord. Multiple malacic foci were found in the midbrain in 5 cases. In contrast, in the 15 calves necropsied in October, there were fewer inflammatory changes, but there was neuronal cell loss in the ventral horn and a decrease in myelinated axons in the lateral and ventral funiculi. Immunohistochemical examination using a rabbit antiserum against Akabane virus strain OBE-1 revealed a large amount of viral antigen in the degenerating neurons and glial cells of the bull calf, mainly in the spinal gray matter. Small amounts of viral antigen in swollen axons and a few glial cells were found in 5 of 27 calves. Thirteen of the 27 calves had high neutralization antibody titers against the Akabane virus, whereas there was no significant antibody titer in most of the calves necropsied during August. The present srudy revealed that viral antigen detection was very useful for the diagnosis of Akabane diseases in the 5-month-old bull calf that was suspected to be infected postnatally, while it had limited usefulness in the other young calves.
Osteopenic Disease in Growing Pigs: Diagnostic Methods Using Serum and Urine Calcium and Phosphorus Values, Parathormone Assay, and Bone Analysis
Authors: Hagemoser Wayne A. , Goff Jesse P. , Sanderson Thomas P. , Haynes Joseph S.
Published: May 2011

This research was performed to evaluate the utility of several serum and urine parameters as well as bone ash and plasma parathormone assay to diagnose and monitor diet-related osteopenia in growing pigs. Five diets were tested as follows: calcium-deficient, phosphorus-replete; moderate-deficiency of calcium and phosphorus; marked deficiency of calcium and phosphorus; calcium replete, phosphorus deficient; and vitamin D deficient. Parameters monitored included serum calcium and phosphorus as well as ratios of urine calcium to creatinine, phosphorus to creatinine, calcium to phosphorus, and percent fractional excretions of calcium and phosphorus. Plasma parathormone (PTH) levels were monitored in 2 of 3 experiments. Osteopenic bone differences at necropsy were evaluated by bone density, percent ash, ash per milliliter bone, calcium per milliliter bone, and phosphorus per milliliter bone. Marked change in urine mineral parameters, especially the calcium-to-phosphorus ratio, typically occurred within 1 to 2 days of treatment and preceded significant change in serum mineral or plasma PTH by 2 to 3 weeks. When monitored, plasma PTH levels were elevated following treatment, which confirms the hyperparathyroid state induced by the test diets. Significant differences in bone mineralization between control and treatment diets at necropsy were generally observed. The results of this study indicate that the analysis of urine minerals offers an early, noninvasive technique to investigate diet-associated osteopenic disease in growing pigs, which can be supported further by bone mineral analysis at postmortem using techniques herein described. Several urine mineral reference intervals for application to field investigations are included. Research into application of similar techniques to evaluate calcium and phosphorus homeostasis in pigs of all ages, including gestating and lactating gilts and sows, appears warranted.
In Vitro Susceptibility of Porcine Respiratory Pathogens to Tilmicosin
Authors: DeRosa D. C. , Veenhuizen M. F. , Bade D. J. , Shryock T. R.
Published: May 2011

Bacterial isolates obtained from swine with various clinical diseases were tested for susceptibility to tilmicosin by minimum inhibitory concentration (MIC) and Kirby-Bauer disk diffusion tests using National Committee on Clinical Laboratory Standards methodology. The tilmicosin MIC90 was ≤0.125 μg/ml for Erysiopelothrix rhusiopathiae, ≤ 1 μg/ml for Haemophilus parasuis isolates, 8 μg/ml for Actinobacillus suis and Pasteurella multocida type A, 16 μg/ml for toxigenic and nontoxigenic P. multocida type D, 64 μg/ml for Bordetella bronchiseptica, and >128 μg/ml for Staphylococcus hyicus and Streptococcus suis. The results of disk diffusion testing matched well with the MIC results for each pathogen. This in vitro survey of tilmicosin activity against various swine isolates suggests that further clinical evaluation of tilmicosin in swine may be warranted for disease associated with E. rhusiopathiae, H. parasuis, and A. suis but not B. bronchiseptica, S. suis, or S. hyicus.
An Autosomal Recessive, Lethal, Neurologic Disease of Gordon Setter Puppies
Authors: Yaeger Michael J. , Majercik Kristin , Carter Margaret , Rothschild Max
Published: May 2011

This report details clinical, necropsy, and pedigree data on an inherited, lethal, neurologic disease of young Gordon Setters. This disorder is characterized by an early age of onset, gait and postural abnormalities, progressive weakness, and recumbency by 5–6 weeks of age. Although clinically distinctive, postmortem changes in affected pups were minimal. Gross lesions were not observed. Microscopic changes were subtle and consisted of astrocyte swelling, primarily in the cerebrocortical and cerebellar white matter, and white matter tracts of the brainstem. Immunohistochemistry for glial fibrillary acidic protein revealed a marked increase in the number and staining intensity of astrocyte cytoplasmic processes in affected pups compared with age-matched controls. Neither cerebral inflammation nor neuronal necrosis was identified. Pedigree analysis of affected litters demonstrated an autosomal recessive mode of inheritance. A diagnosis of this heritable disease should be based on the early age of onset (3–4 weeks of age), characteristic clinical signs, rapid progression to recumbency by 5–6 weeks of age, identification of swollen astrocytes primarily in the cerebellar and cerebrocortical white matter and white matter tracts of the brainstem, and the exclusion of other disease processes.
Serotyping of Mannheimia (Pasteurella) Haemolytica Isolates from the Upper Midwest United States
Authors: Al-Ghamdi Ghanem M. , Ames Trevor R. , Baker John C. , Walker Robert , Chase Christopher C. L. , Frank Glyn H. , Maheswaran Samuel K.
Published: May 2011

Mannheimia (Pasteurella) haemolytica biotype A serotype1 (A1) is the primary bacterial agent responsible for the clinical signs and pathophysiologic events in bovine pneumonic pasteurellosis. The goal of this study was to determine the prevalence of other serotypes of M. haemolytica biotype A organisms obtained from the upper Midwest diagnostic laboratories. A total of 147 M. haemolytica isolates were collected from Minnesota, South Dakota, and Michigan. Isolates were tested against M. haemolytica antisera obtained from the National Animal Disease Center, Ames, Iowa. Results indicated that M. haemolytica serotype 1 represented approximately 60%, serotype 6 represented 26%, and serotype 2 represented 7% of the total examined isolates. In addition, 7% of the isolates were serotype 9, 11, or untypable. This finding suggests that M. haemolytica serotypes other than serotype 1 can be isolated from the lung lesions of diseased cattle and seem to be capable of causing the pathologic changes observed in the lung with pneumonic pasteurellosis.
Immunohistochemical Diagnosis of Chronic Wasting Disease in Preclinically Affected Elk from a Captive Herd
Authors: Peters Jeanine , Miller Janice M. , Jenny Allen L. , Peterson Terry L. , Carmichael K. Paige
Published: May 2011

An immunohistochemical (IHC) method was used to test brain tissues from 17 elk in a captive herd in which chronic wasting disease (CWD) had previously occurred. The IHC technique detects the protease-resistant prion protein (PrP-res), which is considered a disease-specific marker for transmissible spongiform encephalopathies (TSE), regardless of the species affected. Of the 17 elk tested, 10 were positive by IHC. Only 2 of these 10 animals had shown clinical signs and histologic lesions of CWD, and an additional animal had histologic lesions only. The most consistently IHC-positive tissue was medulla oblongata, especially the obex. These results show that the PrP-res IHC test on brain tissue, specifically medulla oblongata at the obex, should be considered an essential component of any surveillance study intended to determine the incidence of CWD in captive or free-ranging cervids.
Comparison of Virus Isolation, Reverse Transcription-Polymerase Chain Reaction, Immunohistochemistry, and in Situ Hybridization for the Detection of Porcine Reproductive and Respiratory Syndrome Virus from Naturally Aborted Fetuses and Stillborn Piglets
Authors: Cheon Doo-Sung , Chae Chanhee
Published: May 2011

Virus isolation, reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and in situ hybridization methods were compared for the detection of porcine reproductive and respiratory syndrome virus (PRRSV). Seven aborted fetuses and 6 stillborn piglets naturally infected with PRRSV were used in the study. Viral antigen and viral nucleic acid were detected in macrophages and dendritic cells in the spleen, tonsil, lymph nodes, and thymus; in macrophages of liver, heart, and lung; and in endothelial cells and myocytes of the heart. Viral antigen and viral nucleic acid were most consistently detected in the spleen. Of the 13 samples, 6 were positive for PRRSV by all 4 techniques. Four (31%) samples were positive for PRRSV by RT-PCR, in situ hybridization, and virus isolation. Two (15%) samples were positive for PRRSV by virus isolation, RT-PCR, and in situ hybridization. One (8%) was positive for PRRSV by virus isolation and RT-PCR. The RT-PCR identified the presence of PRRSV more frequently than the other methods. However, when only formalin-fixed tissues are submitted, immunohistochemistry and in situ hybridization would be useful methods for the detection of PRRSV antigen and nucleic acid.
Polyclonal Sandwich ELISAs to Detect F18 Fimbriated Escherichia Coli in Pigs in Northern Ireland
Authors: Bell Colin , Finlay David , Imberechts Hein , Ball Hywel
Published: May 2011

F18 fimbriated Escherichia coli are a newly described cause of postweaning diarrhea in pigs. Polyclonal rabbit antisera were raised to the antigenic variants, F18ab and F18ac, of these fimbriae and were used to develop monospecific sandwich enzyme-linked immunosorbent assays (ELISAs). The ELISAs were standardized with type cultures characterized by polymerase chain reaction techniques (PCR) and then used to conduct a study of the prevalence of F18 fimbriated E. coli in pigs in Northern Ireland. A total of 176 isolates were tested by ELISA and PCR. Eight isolates were positive for F18 by ELISA, of which 2 were shown to be false positives by PCR and one was PCR positive but ELISA negative. Of the 6 confirmed ELISA positives, all produced VT2 toxin and 3 produced ST toxin. Four positives were from serogroups O138 and O139, previously associated with porcine diarrhea.
Detection of Chlamydial Antibody by Fetal Serology—An Aid to the Diagnosis of Ovine Abortion
Authors: Kennedy Hilary E. , McCullough Samuel J. , Graham David , Cassidy Joseph , Malone Frank E. , Ellis William A.
Published: May 2011

Two serological tests (indirect immunofluorescence and enzyme-linked immunosorbent assay) were developed for the detection of fetal antibody to Chlamydia psittaci. Fetal blood and thoracic fluid from 126 field cases of suspected ovine chlamydial abortion were examined using both tests. Placenta and fetal tissues (lung, liver, and kidney) from the same animals were also examined by the following conventional diagnostic methods: isolation in McCoy cells, detection of chlamydial lipopolysaccharide (LPS), modified Ziehl-Nielsen staining, and direct fluorescent antibody staining of chlamydia in frozen cryostat sections. Seventy cases were positive by fetal serology, and of these, 68 were also positive by isolation and/or LPS detection. The remaining 56 cases had negative fetal serology, and of these, 39 were positive by isolation and/or LPS detection. Results indicate that fetal serology, although less sensitive than either isolation in McCoy cells or detection of chlamydial LPS antigen, may be of particular use when placenta is not available.
Application of Single-Strand Conformation Polymorphism to the Study of Bovine Viral Diarrhea Virus Isolates
Authors: Jones Leandro R. , Weber E. Laura
Published: May 2011

Single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) products is a genetic screening technique for rapid detection of nucleotide substitutions in PCR-amplified genomic DNA or cDNA. It is based on the observation that partially formamide-denatured double-stranded DNA migrates as 2 single-stranded DNA molecules when electrophoresed in nondenaturing polyacrylamide gels. The mobility depends on the 3-dimensional conformation of the strand under the conditions used. It is possible to discriminate between DNA strands differing in only 1 nucleotide. The method was applied to the analysis of Bovine Viral Diarrhea Virus (BVDV) isolates. Reference and Argentinian strains were assessed for variations in their 5' untranslated region (5'-UTR). The PCR products of the 5'-UTR ends were formamide denatured and compared by SSCP analysis in nondenaturing 15% polyacrylamide and 15% polyacrilamide–5% glycerol gels. The reference strains SD-1, Singer, and Oregon C24V had differences in electrophoretic patterns. Despite the high conservation among the 5'-UTR of pestiviruses, the method allowed discrimination among all 9 Argentinian isolates. The 5'-UTR of a fetal kidney–derived isolate (1R93) was PCR amplified and cloned in a plasmid vector; the SSCP analysis of 30 PCR products obtained by direct amplification over randomly selected clones produced 5 different banding patterns, indicating the existence of viral quasispecies. The results show that SSCP may be used to identify and differentiate among BVDV isolates.
Pulmonary Botryomycosis in a Scottish Highland Steer
Authors: Miller Margaret A. , Fales William H. , Tyler Jeff W. , Suedmeyer Wm. Kirk
Published: May 2011

Pertinent necropsy findings in a 5 1/2-year-old Scottish Highland steer with chronic intractable pneumonia and cough were limited to the pulmonary system. The accessory lobe of the lung was collapsed, scarred, and multifocally adhered to parietal pleura. A polypoid mass almost completely obstructed the lobar bronchus and protruded into the trachea; mucopurulent exudate distended more distal bronchi. Botryomycosis was diagnosed when histologic examination revealed pyogranulomatous pneumonia with eosinophilic granules and “club” formation surrounding colonies of gram-positive cocci. Staphylococcus aureus was cultured from the lung. Botryomycosis is an unusual response to infection with common bacteria and is characterized by pyogranulomatous inflammation with formation of eosinophilic granules surrounding colonies of gram-positive cocci or gram-negative bacilli. Among domestic species, staphylococcal botryomycosis is most common as a wound infection in horses or as mastitis in cows and sows. Pulmonary botryomycosis is rare in horses, humans, and guinea pigs and apparently has not been reported in cattle.
Prevalence of Psammoma Bodies in Meninges and Choroid Plexuses of Raccoons (Procyon Lotor) from Parramore Island, Virginia
Authors: Hamir A. N. , Hanlon C. A. , Rupprecht C. E.
Published: May 2011

Microscopic evidence of multifocal mineralizations (psammoma bodies) were seen in brains of 33/53 (62%) raccoons ( Procyon lotor) necropsied on Parramore Island, Virginia. Most mineralized foci had concentric laminations and were present in small capillaries of meninges of the brain (15/33), in choroid plexus (3/33), or at both these sites (13/33). In 2 raccoons, the lesions were confined to the meninges of the proximal cervical spinal cord. In most cases, the affected vessels appeared to have been completely occluded. However, no evidence of ischemic changes in the brain parenchyma was seen, and none of the raccoons had abnormal neurologic signs prior to euthanasia. The condition appears to be a common incidental histopathologic finding in raccoons from the eastern United States. Although the exact cause of this condition is not known, a primary vascular insult with resultant dystrophic mineralization of the affected vessels is suspected.
A Disease Resembling Inclusion Body Disease of Boid Snakes in Captive Palm Vipers (Bothriechis Marchi)
Authors: Raymond James T. , Garner Michael M. , Nordhausen Robert W. , Jacobson Elliot R.
Published: May 2011

Between April 1998 and June 1999, 8 palm vipers ( Bothriechis marchi) were diagnosed with a disease similar to inclusion body disease (IBD) of boids. Six palm vipers were captive bred, and 2 were wild caught. All of the vipers were adults at the time of death. Three palm vipers were found dead with no premonitory clinical signs, and 5 had anorexia plus possibly 1 of the following clinical signs: regurgitation, paresis, and dehydration. Histologically, all snakes had intracytoplasmic, round to oval, single to multiple eosinophilic inclusion bodies in hepatocytes and renal tubular epithelial cells. Inclusion bodies were distributed among other organs with varying frequency. Common concurrent histologic lesions were urate nephrosis, septic thrombi, and hepatocellular degeneration. Ultrastructurally, inclusions had features similar to inclusions in boid snakes with IBD.
Preliminary Findings on the Experimental Transmission of Chronic Wasting Disease Agent of Mule Deer to Cattle
Authors: Hamir Amir N. , Cutlip Randall C. , Miller Janice M. , Williams Elizabeth S. , Stack Mick J. , Miller Michael W. , O'Rourke Katherine I. , Chaplin Melanie J.
Published: May 2011

To determine the transmissibility of chronic wasting disease (CWD) to cattle and to provide information about clinical course, lesions, and suitability of currently used diagnostic procedures for detection of CWD in cattle, 13 calves were inoculated intracerebrally with brain suspension from mule deer naturally affected with CWD. Between 24 and 27 months postinoculation, 3 animals became recumbent and were euthanized. Gross necropsies revealed emaciation in 2 animals and a large pulmonary abscess in the third. Brains were examined for protease-resistant prion protein (PrPres) by immunohistochemistry and Western blotting and for scrapie-associated fibrils (SAFs) by negative-stain electron microscopy. Microscopic lesions in the brain were subtle in 2 animals and absent in the third case. However, all 3 animals were positive for PrPres by immunohistochemistry and Western blot, and SAFs were detected in 2 of the animals. An uninoculated control animal euthanized during the same period did not have PrPres in its brain. These are preliminary observations from a currently in-progress experiment. Three years after the CWD challenge, the 10 remaining inoculated cattle are alive and apparently healthy. These preliminary findings demonstrate that diagnostic techniques currently used for bovine spongiform encephalopathy (BSE) surveillance would also detect CWD in cattle should it occur naturally.
Comparison of Purified Protein Derivatives and Effect of Skin Testing on Results of a Commercial Gamma Interferon Assay for Diagnosis of Tuberculosis in Cattle
Authors: Whipple Diana L. , Palmer Mitchell V. , Slaughter Ralph E. , Jones Stephen L.
Published: May 2011

Purified protein derivatives (PPD) prepared in the USA were compared with those prepared in Australia by a private company (CSL Veterinary) for use with a commercial gamma interferon (γ-IFN) assay for diagnosis of bovine tuberculosis. The effect of skin testing on results of the γ-IFN assay was determined, and results were compared when blood samples were stimulated with PPD within 2 hours and after 24 hours of sample collection. Twenty cattle that were sensitized by subcutaneous injection of heat-killed Mycobacterium bovis were randomly divided into 3 groups. Cattle in group A were tested with the caudal fold skin test (CFT) on day 0 and the comparative cervical skin test (CCT) on day 7. Cattle in group B were tested with the CFT on day 0 and the CCT on day 63, and group C cattle were not skin tested. Blood samples for the γ-IFN assay were collected at various times throughout the study period. Optical density (OD) values for the γ-IFN assay were not significantly different when blood samples were stimulated with US avian PPD and CSL avian PPD. However, OD values were significantly higher for US bovine PPD than for CSL bovine PPD. However, the final interpretation of the γ-IFN assay was usually the same when using either US or CSL PPD. In addition, OD values for the γ-IFN assay were significantly higher for blood samples collected after sensitized cattle were skin tested than for samples collected from the same cattle before skin testing or from cattle not skin tested. The OD values for blood samples stimulated within 2 hours of sample collection were significantly higher than for samples stimulated 24 hours after sample collection. However, OD values for all PPD-stimulated samples from sensitized cattle were significantly higher in samples collected 3 days after skin testing and stimulated 24 hours after collection than for samples from the same animals collected before skin testing and stimulated within 2 hours of sample collection. Results of this study indicate that PPD prepared in the USA or Australia can be used to stimulate blood samples for the γ-IFN assay. Skin testing cattle prior to collection of blood for the γ-IFN assay boosts production of γ-IFN by lymphocytes from cattle that have had prior exposure to M. bovis antigens. Use of the γ-IFN assay in conjunction with skin testing may improve detection of cattle infected with M. bovis. In addition, the increase in production of γ-IFN after skin testing will permit greater flexibility in conducting the assay because samples can be stimulated after they have been shipped overnight rather than only on the day of sample collection.
Detection and Duration of Porcine Reproductive and Respiratory Syndrome Virus in Semen, Serum, Peripheral Blood Mononuclear Cells, and Tissues from Yorkshire, Hampshire, and Landrace Boars
Authors: Christopher-Hennings Jane , Holler Larry D. , Benfield David A. , Nelson Eric A.
Published: May 2011

Because transmission of porcine reproductive and respiratory syndrome virus (PRRSV) can occur through boar semen, it is important to identify persistently infected boars. However, even for boars given the same PRRSV strain and dose, variability in the duration of viral shedding in semen has been observed, suggesting that host factors are involved in PRRSV persistence. To determine whether there are host genetic factors, particularly litter and breed differences related to the persistence of PRRSV, 3 litters from 3 purebred swine breeds were used for this study. It was also determined whether PRRSV could be detected for a longer period of time in serum, semen, or peripheral blood mononuclear cells (PBMC) and if PRRSV could still be detected in tissues after these antemortem specimens were PRRSV negative for a minimum of 2–3 weeks. Three Hampshire, 3 Yorkshire, and 2 Landrace PRRSV-naïve boars were obtained and inoculated intranasally with a wild-type PRRSV isolate (SD-23983). All boars within each breed were from the same litter, and litters were within 9 days of age. Serum and PBMC were collected twice weekly from each boar and analyzed for the presence of PRRSV by virus isolation and the polymerase chain reaction (PCR). Serum was also used to obtain virus neutralization titers and enzyme-linked immunosorbent assay S/P values. Semen was collected twice weekly from 7 of 8 boars and analyzed by PCR. After all specimens were PRRSV negative for a minimum of 2–3 weeks, each boar was euthanized, and 21 tissues plus saliva, serum, feces, and urine were collected. All postmortem specimens were evaluated by virus isolation. Specimens that were PRRSV negative by virus isolation were then evaluated by PCR. The mean number of days (±SD) for the duration of PRRSV shedding in semen was 51 ± 26.9 days, 7.5 ± 4.9 days, and 28.3 ± 17.5 days for Landrace, Yorkshire, and Hampshire boars, respectively. Because of small sample sizes and large SDs, the differences in duration of PRRSV shedding in semen between breeds were not considered significant. However, the trend suggested that Yorkshire boars were more resistant to PRRSV shedding in semen than were Landrace boars, requiring further investigation using a larger numbers of boars. PRRSV was detected for a longer period in semen than in serum or PBMC in 4 of 7 boars. Viremia could be detected for a longer period in serum than in PBMC in 6 of 8 boars. After a minimum of 2–3 weeks of PRRSV-negative serum, semen, and PBMC, PRRSV could still be detected in the tonsil of 3 of 8 boars by virus isolation, indicating that boars still harbor PRRSV within the tonsil even though antemortem specimens are PRRSV negative.
Paramyxovirus Infection in Caiman Lizards (Draecena Guianensis)
Authors: Jacobson Elliott R. , Origgi Francesco , Pessier Allan P. , Lamirande Elaine W. , Walker Ian , Whitaker Brent , Stalis Ilse H. , Nordhausen Robert , Owens Jennie W. , Nichols Donald K. , Heard Darryl , Homer Bruce
Published: May 2011

Three separate epidemics occurred in caiman lizards ( Dracaena guianensis) that were imported into the USA from Peru in late 1998 and early 1999. Histologic evaluation of tissues from necropsied lizards demonstrated a proliferative pneumonia. Electron microscopic examination of lung tissue revealed a virus that was consistent with members of the family Paramyxoviridae. Using a rabbit polyclonal antibody against an isolate of ophidian (snake) paramyxovirus, an immunoperoxidase staining technique demonstrated immunoreactivity within pulmonary epithelial cells of 1 lizard. Homogenates of lung, brain, liver, or kidney from affected lizards were placed in flasks containing monolayers of either terrapene heart cells or viper heart cells. Five to 10 days later, syncytial cells formed. When Vero cells were inoculated with supernatant of infected terrapene heart cells, similar syncytial cells developed. Electron microscopic evaluation of infected terrapene heart cells revealed intracyto-plasmic inclusions consisting of nucleocapsid strands. Using negative-staining electron microscopy, abundant filamentous nucleocapsid material with a herringbone structure typical of the Paramyxoviridae was observed in culture medium of infected viper heart cells. Seven months following the initial epizootic, blood samples were collected from surviving group 1 lizards, and a hemagglutination inhibition assay was performed to determine presence of specific antibody against the caiman lizard isolate. Of the 17 lizards sampled, 7 had titers of <1:20 and 10 had titers of >1:20 and <1:80. This report is only the second of a paramyxovirus identified in a lizard and is the first to snow the relationship between histologic and ultrastructural findings and virus isolation.
Diagnosis of Preclinical and Subclinical Scrapie in a Naturally Infected Sheep Flock Utilizing Currently Available Postmortem Diagnostic Techniques
Authors: Hamir Amir N. , Miller Janice M. , Schmerr Mary Jo , Stack Mick J. , Chaplin Melanie J. , Cutlip Randall C.
Published: May 2011

Scrapie is a naturally occurring transmissible encephalopathy of sheep and goats. Currently available methods for diagnosis are the presence of characteristic histopathologic changes and detection of an abnormal form of prion protein (PrPres) in the brains of affected animals. This study documents preclinical and subclinical scrapie in a flock of 16 sheep utilizing histopathology, immunohistochemistry (IHC), western blot, and electron microscopy (for scrapie-associated fibrils) for confirmation of the disease. Prior to necropsy, none of the sheep showed signs of clinical scrapie. Based on the results of histopathology and positive PrPres tests, 3 ewes were found to have subclinical scrapie. An additional ewe, which did not have histopathologic changes in the brain but was positive by IHC and western blot, was considered a preclinical case of scrapie. None of the sheep had amyloid in the brain stem.
Orbital Adenocarcinoma of Lacrimal Gland Origin in a Dog
Authors: Wang Fun-In , Ting Chao T. , Liu Yi-Shing
Published: May 2011

A 13-year-old intact female mixed-breed dog was presented for a progressive enlargement of the right eye, which had been treated previously for conjunctivitis. A round, firm mass, approximately 4 cm in diameter, was protruding from the superotemporal aspect of the right orbit, displacing the eyeball anteriorly and ventromedially. The mass was encapsulated, distinct from the eyeball, and not associated with the eyelids. On cut surface, there was a pale multilobulated periphery, with a dark red, soft, and depressed core. Histolog-ically, tumor cells formed cords and tubules, which were stained with mouse anti-human cytokeratin antibody AE1/AE3. Residual glands were serous, and the majority of tumor cells were negative for mucin. The supraorbital location, encapsulation, and residual serous glands suggest that this mass was a low-grade adenocarci-noma of the lacrimal gland.
Unilateral Concurrence of Pyelocaliceal Diverticula and Intracapsular Angiomyolipoma in the Kidney of a Cat
Authors: Wang Fun-In , Liang S. L. , Chen G. H. , Chen D. U.
Published: May 2011

A 7-month-old cat was examined for progressive abdominal distension. Radiography showed a fluid-containing cyst, which had subsequently ruptured as the result of a fall. Nephrectomy was performed, and examination revealed the coexistence of pyelocaliceal diverticula with a cystic intracapsular angiomyolipoma (mesenchymal hamartoma) in the left kidney. The diverticula were present on both cranial and caudal poles of the kidney and were lined by transitional epithelium. The hamartoma was characterized by the presence of multiple mesenchymal tissues, including thick-walled blood vessels, smooth muscle, and adipose tissue.
Rare Detection of Neospora Caninum in Placentas from Seropositive Dams Giving Birth to Full-Term Calves
Authors: Bergeron Nadia , Girard Christiane , Paré Julie , Fecteau Gilles , Robinson John , Baillargeon Paul
Published: May 2011

Neospora caninum is thought to be transmitted to cattle by dogs, the only known definitive host. Although aborted fetuses seem the most likely source of infective material for dogs, placentas from seropositive dams appear also as a potential source of infective material. The objective of the study was to evaluate the presence of N. caninum organisms in placentas of full-term calves born to seropositive cows. Sixteen placentas, 11 from Neospora-seropositive cows, were examined histologically and by immunohistochemistry and polymerase chain reaction (PCR) assay for the presence of N. caninum. Mild placentitis was observed in all placentas. Neospora caninum was not identified by immunohistochemistry, but placentas from 2 seropositive dams were positive for N. caninum by PCR. These results suggest that placentas of full-term calves from seropositive cows may be a potential source of N. caninum for dogs, but the incidence of this mode of transmission is likely to be low.
Effect of Dietary Factors on the Detection of Fecal Occult Blood in Cats
Authors: Tuffli Silvia Puhl , Gaschen Frédéric , Neiger Reto
Published: May 2011

Eight different diets were each fed to 6 cats to evaluate the effect on a guaiac and an o-tolidine fecal occult blood test. Fecal samples were collected from day 5 through day 7. Canine blood or pure cottage cheese were used as positive and negative controls, respectively. One hundred thirty-four fecal samples were analyzed. The dry fish (capelin) and vegetable (tapioca) diet and the pure cottage cheese diet had only negative results in both tests, whereas a canned chicken and cereal (rice) diet had negative results in all fecal samples in the o-tolidine tablet test and in 10 of 16 fecal samples in the guaiac paper test. All other fecal samples from cats eating 6 other diets and the canine blood additive were positive in both fecal occult blood tests. These results indicate that occult blood tests based on o-tolidine and guaiac are clinically useful, but cats need to be on a strict diet before the tests are used.
Salpingitis in Pekin Ducks Associated with Concurrent Infection with Tetratrichomonas sp. and Escherichia Coli
Authors: Crespo Rocio , Walker Richard L. , Nordhausen Robert , Sawyer Sherilyn J. , Manalac Rosa B.
Published: May 2011

Increased mortality (1.5% per week) and low egg production (5–10% lower than normal) were observed in a flock of domestic breeding Pekin ducks ( Anas platyrhynchos). At necropsy, salpingitis and peritonitis were the most significant findings. Histologically, there was accumulation of necrotic debris in the lumen of the oviduct. Numerous bacteria and trichomonads were observed histologically in the lumen of the vagina and occasionally in the shell gland. Escherichia coli and a trichomonad were isolated from the oviduct. The trichomonads were oval (6–8 μm long, 4.5–6 μm wide) and had 4 anterior flagella and an undulating membrane extending over the entire length of the body, finishing in a long posterior flagellum. Morphology was consistent with trichomonads of the genus Tetratrichomonas. Comparative sequence analysis of the 5.8S ribosomal RNA gene and the flanking internal transcribed space regions of the trichomonad isolate did not closely match with available sequences of the same region of other trichomonadid protozoa.
Validation of a Competitive Enzyme-Linked Immunosorbent Assay for Diagnosing Babesia Equi Infections of Moroccan Origin and Its Use in Determining the Seroprevalence of B. Equi in Morocco
Authors: Rhalem Abdelkebir , Sahibi Hamid , Lasri Saadia , Johnson W. Carl , Kappmeyer Lowell S. , Hamidouch Ahmed , Knowles Donald P. , Goff Will L.
Published: May 2011

A highly specific and sensitive competitive enzyme-linked immunosorbent assay for detection of specific antibody to Babesia equi in serum from equids was validated for use in Morocco. The assay is based on the specific inhibition of binding of a monoclonal antibody to a conserved epitope within a recombinant parasite peptide by serum from infected animals. The assay was compared to an established indirect immunofluorescence assay, with a concordance of 91%. The assay was used to determine seroprevalence for B. equi infections in donkeys and horses throughout Morocco. A total of 578 sera (163 horses and 415 donkeys) from 6 locations representing different bioclimatic regions were assayed. An analysis of variance, indicated no significant effect of location; however, donkeys were significantly more likely than horses to be seropositive. Management conditions contribute to greater tick infestations and thus Babesia exposure in donkeys than in horses.