bluuebunny/crossref_metadata_2025 huggingface dataset:
Porcine Circoviruses: A Review
Authors: Allan Gordon M. , Ellis John A.
Published: May 2011

Porcine circoviruses (PCV) are small nonenveloped DNA viruses containing a unique single-stranded circular genome. Previously, no recognized link was found between PCV infection of pigs and disease, and PCV was considered a nonpathogenic agent. Over the last 5 years, a “novel” PCV, designated PCV2, has been associated with various disease syndromes in pigs, primarily postweaning multisystemic wasting syndrome (PMWS). Pigs with PMWS have a variety of clinical signs, including debility, dyspnea, palpable lymphadenopathy, diarrhea, and pallor or icterus. Lesions associated with the presence of PCV2 in a variety of cell types include lymphohistiocytic to granulomatous interstitial pneumonia, hepatitis, nephritis, myocarditis, enteritis, and pancreatitis. The lesions of PMWS have been reproduced experimentally after inoculation of piglets with PCV2 cell culture isolates, although the full expression of the disease syndrome may require the presence of other agents such as porcine parvovirus or porcine reproductive and respiratory syndrome (PRRS) virus. Recent reports have linked PCV2 to other disorders in pigs, ranging from abortion and reproductive failure to “atypical” PRRS. Available data indicate high seroprevalence of antibodies to PCV2 worldwide. The diagnosis of PCV2-associated disease is based on the direct demonstration of PCV2 antigens or nucleic acid in affected tissues. PCV2 is now regarded as an important emerging pathogen. Although vertical transmission has been documented, the epidemiology of PCV2 infections is poorly understood, as is the role of the immune response in controlling or augmenting disease.
Gas Chromatography/Mass Spectrometry Identification and Quantification of Isazophos in a Famphur Pour-On and in Bovine Tissues after a Toxic Exposure
Authors: Braselton W. Emmett , Johnson Jerre L. , Carlson Michael P. , Schneider Norman R.
Published: May 2011

A sample identified as “Warbex pour-on,” expected to contain 13.2% famphur, and bovine tissue samples from 2 heifers that died after exhibiting signs of organophosphate intoxication were analyzed by gas chromatography/mass spectrometry (GC/MS). A product formulation problem was suspected because brain cholinesterase activities were depressed in both animals. Electron impact (EI) GC/MS of the pour-on revealed 9.7% famphur and an unidentified peak with approximately 76% of the peak area of the famphur. The unidentified peak showed a molecular ion at m/z 313, with a single Cl isotope cluster. Methane chemical ionization (MeCI) MS confirmed the molecular weight at 313 (1 Cl). A search on the molecular formula C9H17N3O3PSCl yielded a single match, isazophos. EI and MeCI GC/MS of reference isazophos confirmed the identity of the suspect peak. The concentration of isazophos in the pour-on was determined to be 6.0%. Famphur and isazophos were identified by their EI spectra and GC retention times in extracts of liver and brain from the 2 deceased animals. A GC/MS procedure utilizing selected ion monitoring (SIM) was developed for quantification of isazophos in liver, kidney, muscle, and fat of additional affected animals sacrificed at various times after exposure. Isazophos remained in animal tissues for as long as 94 days after topical exposure. Isazophos was present in fetal liver 70 days after exposure of the dam. High levels (6–3,500 ppm) of isazophos and famphur remained on the skin at 39 days postexposure.
Improved Plating Media for the Detection of Salmonella Species with Typical and Atypical Hydrogen Sulfide Production
Authors: Mallinson E. T. , Miller R. G. , de Rezende C. E. , Ferris K. E. , de Graft-Hanson J. , Joseph S. W.
Published: May 2011

The Salmonella detection ability of 2 surfactant-supplemental media, xylose-lysine-tergitol (Nia-proof) 4 (XLT4) and Miller-Mallinson (MM) agar, was compared against that of several commonly used plating media. XLT4 and MM appeared to be the most efficient in detecting Salmonella in meat products and food animal environments. MM was superior to XLT4 in detecting those increasingly more prevalent strains of Salmonella possessing weak to ultraweak H2S production characteristics.
Apoptotic and Proliferation Indexes in Canine Lymphoma
Authors: Phillips Brenda S. , Kass Philip H. , Naydan Diane K. , Winthrop Michelle D. , Griffey Stephen M. , Madewell Bruce R.
Published: May 2011

Proliferative and apoptotic fractions of tumors were evaluated in 41 dogs with lymphoma for prediction of response to chemotherapy. All dogs had advanced clinical stage tumors, were untreated prior to study, and received identical induction-remission chemotherapy. Tumor cell proliferation was determined in all pretreatment biopsy specimens and in 18 specimens collected at the time of clinical relapse from remission. Quantitative measures included mitotic index and immunoreactivities for proliferating cell nuclear antigen (PCNA) and Ki-67. Apoptotic index was evaluated from 40 dogs pretreatment and from 16 dogs at the time of first relapse. Pretreatment tumor values for Ki-67, PCNA, and apoptosis were compared with posttreatment values. The median first relapse-free interval (RFI) and overall survival (OS) time were 174 days and 445 days, respectively. Of the proliferation markers, only the results of the Ki-67 analysis were predictive for duration of the first RFI but not OS. Pretreatment apoptotic index was also predictive of the duration of first RFI but not OS. No significant predictive value for comparison of the pretreatment and postrelapse values was demonstrated. Ki-67 labeling index and apoptotic indexes were combined to form both a proliferation/apoptotic ratio (PAR) and a sum, or turnover index. Only the PAR was predictive for duration of first RFI on multivariate analysis. Other variables that were evaluated for their influence on treatment outcome included patient age, weight, gender, clinical stage, clinical substage, and tumor immunophenotype. Of these variables, only immunophenotype was found to be of value for predicting duration of first RFI and OS.
Evaluation of a Novel Enzyme-Linked Immunosorbent Assay for Detection of Antibodies against Salmonella, Employing a Stable Coating of Lipopolysaccharide-Derived Antigens Covalently Attached to Polystyrene Microwells
Authors: Wiuff Camilla , Jauho Eva Stenbæk , Stryhn Henrik , Andresen Lars Ole , Thaulov Karina , Boas Ulrik , Jakobsen Mogens Havsteen , Heegaard Peter M. H.
Published: May 2011

Polysaccharides derived from Salmonella typhimurium lipopolysaccharide (LPS) representing the O-antigen factors 1, 4, 5, and 12 and the O-antigen factors 6 and 7 from Salmonella choleraesuis LPS were derivatized with the photoreactive compound anthraquinone and subsequently covalently coupled to microtiter polystyrene plates by ultraviolet irradiation. Both polysaccharide antigens could be coupled simultaneously to the same microtiter plate. The coated surface was used in indirect ELISA for the determination of serum antibodies from pigs infected with bacteria of the two Salmonella groups and from uninfected pigs. This ELISA proved itself by having a good long-term durability and a high degree of reproducibility, including low day-to-day variations and low interplate variations. Furthermore, the ELISA showed good specificity and sensitivity when data were compared with the optical density levels of a panel of pig sera as determined by a conventional ELISA on the basis of passive coating of the two Salmonella LPS antigens (the mix-ELISA). The covalent anthraquinone mix-ELISA shows promise as a stable and durable alternative to the existing conventional ELISA for serological surveillance of Salmonella infections in pigs.
Halicephalobus Gingivalis (H. Deletrix) Infection in Two Horses in Southern California
Authors: Kinde H. , Mathews M. , Ash L. , St. Leger J.
Published: May 2011

Two horses, a 16-year-old male Holsteiner and a 5-year-old male miniature horse, were diagnosed with halicephalobiasis at the California Veterinary Diagnostic Laboratory System, San Bernardino Branch, in April and June of 1998. Over a period of 4 weeks, the Holsteiner horse developed renal dysfunction, blepharospasm, and blindness in the right eye. A 15-cm-diameter mass was detected on ultrasound examination in the right kidney. Terminally, the animal developed seizures and was euthanized. The miniature horse had a 6-week-long illness characterized by testicular enlargement and uveitis. This animal developed ataxia and died. Necropsy examination revealed bilateral enlargement of the kidneys in both horses, petechial hemorrhages of the optic nerve (Holsteiner), and a diffusely firm and enlarged left testicle (miniature horse). Microscopic evaluation of tissues revealed granulomatous nephritis, optic neuritis, retinits, and encephalitis in both horses and orchitis in only the miniature horse with intralesional rhabditiform nematodes. Halicephalobus gingivalis was found in the urine sediment of both animals and in semen of the Holsteiner horse.
Isolation of Avian Pneumovirus from an Outbreak of Respiratory Illness in Minnesota Turkeys
Authors: Goyal Sagar M. , Chiang Shu-Ju , Dar Arshud M. , Nagaraja K. V. , Shaw Daniel P. , Halvorson David A. , Kapur Vivek
Published: May 2011

Antibodies to avian pneumovirus (APV) were first detected in Minnesota turkeys in 1997. Virus isolation was attempted on 32 samples (28 tracheal swabs, 4 pools of trachea and turbinates) that were positive for APV by reverse transcriptase polymerase chain reaction (RT-PCR). The cell cultures used were chicken embryo fibroblast (CEF), Vero cells, and QT-35 cells. Five virus isolates were obtained from these samples, and the identity of the isolates was confirmed by RT-PCR. Four isolates were obtained by inoculation of CEF cells, and 1 isolate was obtained in QT-35 cells after 3–7 blind passages in cell cultures. Vero cells did not yield any isolate on primary isolation; however, all 5 isolates could be adapted to grow in Vero cells following primary isolation in CEF or QT-35 cells. This is the first report of isolation of APV in Minnesota and also the first report of primary isolation of APV in QT-35 cells.
Listeria Monocytogenes Septicemia in a Thoroughbred Foal
Authors: Wilkins Pamela A. , Marsh Peggy S. , Acland Helen , Del Piero Fabio
Published: May 2011

Listeria monocytogenes septicemia was diagnosed in a 6-day-old Thoroughbred foal. Primary clinical signs included fever, depression, diarrhea, and respiratory distress. Hematologic abnormalities included leukopenia, neutropenia, degenerative left shift, and hyperfibrinogenemia. Clinical chemistry and blood gas abnormalities included metabolic acidosis, hypoxemia, hypocapnia, hypoglycemia, and hyponatremia. Despite aggressive therapeutic intervention and intensive care, the foal died within 12 hours of admission. A postmortem examination was performed, and the primary gross lesion was bilaterally severe, focally extensive bronchopneumonia. Histopathology revealed severe subacute multifocal suppurative bronchopneumonia with necrotizing vasculitis and intralesional coccobacilli. Cultures of blood collected at admission and immediately prior to death were positive for L. monocytogenes, as were cultures obtained from lung and liver at necropsy. Immunohisto-chemical examination of formalin-fixed tissues revealed abundant intra- and extracellular L. monocytogenes antigen within the lung and intravascularly in multiple organs.
Chromobacteriosis in a Chinese Red Panda (Ailurus Fulgens Styani)
Authors: Dyer N. W. , Krogh D. F. , DeVold R. , Wilson S. L. , White D. G.
Published: May 2011

An adult Chinese red panda ( Ailurus fulgens styani) transported by airplane from Florida to a North Dakota zoo died 1 week after arrival. Grossly, an interscapular abscess, subcutaneous inflammation, lymphadenitis, and pulmonary abscesses were observed. Microscopic findings included necrotizing inflammation in liver, lung, lymph node, and spleen. Chromobacterium violaceum was cultured from the interscapular abscess, liver, lung, and spleen and was injected into Swiss Webster mice. These mice died 18 hours postinoculation, and C. violaceum was cultured from liver, lung, and spleen. Chromobacterium violaceum is a sporadically reported but highly virulent pathogenic bacterium of both animals and humans typically found as a soil and water inhabitant of tropical and subtropical regions.
Comparison of Virus Isolation and Reverse Transcription Polymerase Chain Reaction Assay for Detection of Bovine Viral Diarrhea Virus in Bulk Milk Tank Samples
Authors: Renshaw R. W. , Ray R. , Dubovi E. J.
Published: May 2011

The use of a reverse transcriptase polymerase chain reaction (RT-PCR) assay to screen bulk milk tank samples for bovine viral diarrhea virus (BVDV) has proven to be a sensitive and economical means to evaluate the lactating animals in a herd. The assay is capable of detecting the presence of a single persistently infected animal within a group of several hundred cows. Over a 3–year period, 144 samples from 97 farms were tested for BVDV using an RT-PCR assay in conjunction with a classical virus isolation (VI) procedure to measure the relative effectiveness of the techniques. Virus could be detected with both methods when the milk from a single persistently infected animal was diluted 1:600 with the milk from a herd of BVDV-negative animals. Based on individual farms, there was an overall prevalence of 12.4% BVDV infection, and the correlation between the 2 assays was 95.9%. In terms of sensitivity, specificity, and turnaround time, RT-PCR was superior to VI. However, of the 17 samples that were VI positive, 4 were RT-PCR negative. RT-PCR may not detect all naturally occurring BVDV isolates because they may contain minor sequence variations in the primer regions. VI and RT-PCR are both suitable for detection of BVDV in bulk milk samples when used independently, but to increase the probability of successful detection and to provide cross-checks against assay contamination, it is desirable to utilize both methods in parallel.
Diagnosis of Feline Herpesvirus Infection by Immunohistochemistry, Polymerase Chain Reaction, and in Situ Hybridization
Authors: Suchy A. , Bauder B. , Gelbmann W. , Löhr C. V. , Teifke J. P. , Weissenböck H.
Published: May 2011

An adult domestic shorthair cat had severe chemosis due to purulent and necrotizing blepharitis and conjunctivitis. Purulent rhinitis, necrotizing glossitis, and dermatitis were also diagnosed. The cat was positive for feline immundeficiency virus and feline leukemia virus. Histologically, intranuclear Cowdry type A inclusions were found within numerous epithelial cells adjacent to the lesions in skin, conjunctiva, and tongue. Electron microscopic examination revealed herpesviral particles within the lesions. Paraffin-embedded skin and tongue tissues were processed in a polymerase chain reaction, using primers to amplify a 306-bp region of the thymidine kinase gene of feline herpesvirus type 1, resulting in a distinct amplification product of the predicted size. The distribution of feline herpesvirus was demonstrated by immunohistochemistry and nonradioactive in situ hybridization. Positive immunostaining was found in nuclei and cytoplasm of numerous epithelial cells within and next to the lesions, whereas in situ hybridization, performed with a digoxigenin-labeled double-stranded DNA probe, revealed hybridization signal only in nuclei of intact epithelial cells. Neither immunohistochemistry nor in situ hybridization showed feline herpesvirus type 1 in tissues of lungs, liver, spleen, intestine, or brain.
Pooled-Sample Testing as a Herd-Screening Tool for Detection of Bovine Viral Diarrhea Virus Persistently Infected Cattle
Authors: Muñoz-Zanzi Claudia A. , Johnson Wesley O. , Thurmond Mark C. , Hietala Sharon K.
Published: May 2011

The study was conducted to develop methodology for least-cost strategies for using polymerase chain reaction (PCR)/probe testing of pooled blood samples to identify animals in a herd persistently infected with bovine viral diarrhea virus (BVDV). Cost was estimated for 5 protocols using Monte Carlo simulations for herd prevalences of BVDV persistent infection (BVDV-PI) ranging from 0.5% to 3%, assuming a cost for a PCR/probe test of $20. The protocol associated with the least cost per cow involved an initial testing of pools followed by repooling and testing of positive pools. For a herd prevalence of 1%, the least cost per cow was $2.64 (95% prediction interval = $1.72, $3.68), where pool sizes for the initial and repooled testing were 20 and 5 blood samples per pool, respectively. Optimization of the least cost for pooled-sample testing depended on how well a presumed prevalence of BVDV-PI approximated the true prevalence of BVDV infection in the herd. As prevalence increased beyond 3%, the least cost increased, thereby diminishing the competitive benefit of pooled testing. The protocols presented for sample pooling have general application to screening or surveillance using a sensitive diagnostic test to detect very low prevalence diseases or pathogens in flocks or herds.
Single-Dilution Enzyme-Linked Immunosorbent Assay for Quantification of Antigen-Specific Salmonid Antibody
Authors: Alcorn Stewart W. , Pascho Ronald J.
Published: May 2011

An enzyme-linked immunosorbent assay (ELISA) was developed on the basis of testing a single dilution of serum to quantify the level of antibody to the p57 protein of Renibacterium salmoninarum in sockeye salmon ( Oncorhynchus nerka). The levels of antibody were interpolated from a standard curve constructed by relating the optical densities (OD) produced by several dilutions of a high-titer rainbow trout ( O. mykiss) antiserum to the p57 protein. The ELISA OD values produced by as many as 36 test sera on each microplate were compared with the standard curve to calculate the antigen-specific antibody activity. Repeated measurements of 36 samples on 3 microplates on each of 6 assay dates indicated that the mean intraassay coefficient of variation (CV) was 6.68% (range, 0–23%) and the mean interassay CV was 8.29% (range, 4–16%). The antibody levels determined for the serum sample from 24 sockeye salmon vaccinated with a recombinant p57 protein generally were correlated with the levels determined by endpoint titration ( r2 = 0.936) and with results from another ELISA that was based on extrapolation of antibody levels from a standard curve ( r2 = 0.956). The single-dilution antibody ELISA described here increases the number of samples that can be tested on each microplate compared with immunoassays based on analysis of several dilutions of each test serum. It includes controls for interassay standardization and can be used to test fish weighing <3 g.
Evaluation of a Blocking ELISA Using a Urease Conjugate for the Detection of Antibodies to Pseudorabies Virus
Authors: Echeverría Maria Gabriela , Nosetto Edgardo Omar , Etcheverrigaray Maria Elisa
Published: May 2011

A blocking enzyme-linked immunosorbent assay (ELISA) using a urease conjugate (U-B-ELISA) was evaluated for screening sera for antibodies to pseudorabies virus under field conditions. A total of 764 serum samples were analyzed by U-B-ELISA. Of these, 264 were evaluated by both virus neutralization and U-B-ELISA, and the results were compared. U-B-ELISA showed 98.5% and 98.9% sensitivity and specificity, respectively. This test combines the sensitivity and specificity of the blocking ELISA format while allowing visual assessment of results.
Extramedullary Plasmacytoma in a Horse with Ptyalism and Dysphagia
Authors: McConkey Sandra , López Alfonso , Pringle John
Published: May 2011

A Clydesdale mare was examined for weight loss, inappetence, ptyalism, and dysphagia. The main abnormality revealed by serum biochemistry was a marked hyperglobulinemia, and protein electrophoresis revealed a monoclonal gammopathy in the gamma region. The urine was positive for Bence Jones proteins. These findings suggested a plasma cell tumor. The neoplasm could not be located with extensive antemortem examination. At postmortem, neoplastic cells morphologically compatible with plasma cells and positive for equine IgG with imunoperoxidase staining infiltrated the pericardium, mediastinal stromal tissues, adrenal glands, meninges, atrioventricular valves, aorta, abdominal and thoracic fat, and nerves, including the trigeminal nerve. The neoplastic cells invading the cranial nerves were responsible for many of the presenting signs.
Papillomatous Pastern Dermatitis with Spirochetes and Pelodera Strongyloides in a Tennessee Walking Horse
Authors: Rashmir-Raven Ann M. , Black Sharon S. , Rickard Lora G. , Akin Mark
Published: May 2011

Papillomatous digital dermatitis is a common disease in cattle. The pastern dermatitis observed in a horse shared many of the gross characteristics of papillomatous digital dermatitis in cattle. Lesions included a mixture of proliferative and erosive changes, with a verrucose appearance in some areas. Microscopic similarities included pseudoepitheliomatous and papillomatous epidermal hyperplasia with hyperkeratosis, spongiosis of the epidermis, and intraepidermal spirochetes. The horse was also concurrently infected with Pelodera strongyloides. Papillomatous digital dermatitis in cattle is associated with poor husbandry practices. The environment of the affected horse was heavily contaminated with urine, manure, and other organic debris. Verrucous pododermatitis of horses may be the same as or similar to bovine papillomatous digital dermatitis, and these conditions have similar etiologies.
Optimization of Immunohistochemical Methods using two Different Antigen Retrieval Methods on Formalin-Fixed, Paraffin-Embedded Tissues: Experience with 63 Markers
Authors: Ramos-Vara José A. , Beissenherz Marilyn E.
Published: May 2011

Formalin fixation produces cross-links between the proteins and the fixative that alter the ability of some antibodies to recognize antigens. We used formalin-fixed, paraffin-embedded tissues to compare two different antigen retrieval methods for 63 antibodies used in the diagnosis of infectious and neoplastic diseases of animal species. Eighty-four percent of the antibodies needed some type of antigen retrieval for optimal results. Of those antibodies, 67.7% were monoclonal and 32.3% were polyclonal. Steam heat was the method of choice for 31 antibodies. Ten antibodies reacted only with steam heat, but 9 antibodies did not react when steam heat was used. Optimal results were obtained with enzyme digestion for 22 antibodies. Only 10 antibodies yielded optimal results without antigen retrieval; 64% of these antibodies were polyclonal. All antibodies against cytokeratins were optimally retrieved with proteinese K. Antigen retrieval appears to be necessary for the majority of antibodies when used with formalin-fixed, paraffin-embedded tissues.
Comparison of Postmortem Techniques for the Detection of Mycobacterium Bovis in White-Tailed Deer (Odocoileus Virginianus)
Authors: Fitzgerald Scott D. , Kaneene John B. , Butler Kelly L. , Clarke Kathy R. , Fierke Jean S. , Schmitt Stephen M. , Bruning-Fann Colleen S. , Mitchell Rachel R. , Berry Dale E. , Payeur Janet B.
Published: May 2011

A retrospective study of various diagnostic postmortem techniques used in a 4-year surveillance program for detection of Mycobacterium bovis infection in wild white-tailed deer ( Odocoileus virginianus) was conducted. The tests evaluated were routine histopathology, acid-fast staining, detection of acid-fast bacilli in culture, and an M. tuberculosis group-specific genetic probe applied to pure cultures. Each of these techniques were compared with a reference or “gold standard” of mycobacterial culture and identification. Histopathology, the most rapid form of testing for M. bovis infection in white-tailed deer samples, had a sensitivity of 98% and a specificity of 87%, resulting in a positive predictive value of 94%. The detection of acid-fast bacilli by staining was less sensitive than histopathology (90%), but its higher specificity (97%) resulted in a positive predictive value of 99%. The detection of acid-fast bacilli on culture was both highly specific (93%) and sensitive (100%). The group-specific genetic probe had the highest sensitivity and specificity and produced results in complete agreement with those of mycobacterial culture, suggesting that this technique could be used as the new “gold standard” for this particular wildlife tuberculosis surveillance program.
Survival of Clostridium Difficile and Its Toxins in Equine Feces: Implications for Diagnostic Test Selection and Interpretation
Authors: Weese J. Scott , Staempfli Henri R. , Prescott John F.
Published: May 2011

Although Clostridium difficile is recognized as a cause of enterocolitis in horses and humans, there has been little work published regarding the lability of C. difficile and its toxins in feces. A significant decrease in recovery of C. difficile from inoculated equine fecal samples occurred during storage. Recovery after storage in air at 4°C decreased from 76% (37/49) after 24 hours to 67% (33/49) at 48 hours and 29% (14/49) after 72 hours. In contrast to aerobic storage, 25 of 26 samples stored anaerobically at 4°C yielded growth of C. difficile for 30 days, whereas the organism was only detected for 2.5 ± 2.52 days (x ± SD) in paired samples stored aerobically. The use of an anaerobic transport medium was effective in maintaining viability of C. difficile. These findings indicate that poor aerotolerance is the reason for the rapid decrease in culture yield. In contrast to C. difficile organisms stored aerobically at 4°C, C. difficile toxins were considerably more stable and could be detected by enzyme-linked immunosorbent assay in both broth and inoculated fecal samples for at least 30 days. The poor survival of C. difficile but the stability of its toxins when feces are stored aerobically must be considered when submitting samples for diagnosis of C. difficile-associated enterocolitis in horses and when interpreting laboratory results.
Specificity of four Serologic Assays for Mycobacterium Avium ss Paratuberculosis in Llamas and Alpacas: A Single Herd Study
Authors: Miller David S. , Collins Michael T. , Smith Bradford B. , Anderson Phillip R. , Kramsky Joely , Wilder Gwen , Hope Ann
Published: May 2011

An investigation was conducted for Mycobacterium avium ss paratuberculosis infections in a research herd of llamas and alpacas. Herd culture-negative status was established over a 23-month period by screening any individuals with any signs compatible with paratuberculosis ( n = 1), high serology values ( n = 8), or other health and research related reasons ( n = 24). There were no M. avium ss paratuberculosis isolates from radiometric cultures of multiple tissue and fecal samples from these individuals and no known sources of exposure. Paratuberculosis is uncommon in North American llamas and alpacas: only 5 cases were identified after an extensive search of the Veterinary Medical Data Base, diagnostic laboratory records, publication databases, and personal communications. Therefore, serum samples from llamas ( n = 84) and alpacas ( n = 16) in the culture-negative herd were used to obtain preliminary estimates of test specificity for 3 enzyme-linked immunoassays (ELISAs) and an agar gel immunodiffusion (AGID) assay kit for detecting serum antibodies to M. avium ss paratuberculosis in South American camelids. The ELISAs were modifications of established bovine assays for antibody detection. With provisional cutoffs, ELISA-A had 52 false positives (specificity 48%), ELISA-B had 8 false positives (specificity 92%), ELISA-C had two false positives (specificity 98%), and the AGID had 0 false positives (specificity 100%). The range of ELISA values for culture-positive llamas and alpacas ( n = 10) from other herds overlapped the range of values for culture-negative llamas and alpacas. The accuracy of the ELISAs may be improved by using age- and sex-specific cutoffs because uninfected male llamas and alpacas that were older than 1 year had higher values for some tests. These tests can be used for either llamas or alpacas; the protein-G conjugate ELISA (ELISA-B) may be useful for multispecies applications. These assays are best used for rapid presumptive diagnoses of llamas and alpacas with diarrhea and weight loss and as a screening tool for herds known to be exposed to infection. All seropositive results should be confirmed with culture.
Effects of Antigen-Retrieval Pretreatments for Immunohistochemical Detection of Akabane Viral Antigen
Authors: Haritani Makoto , Hirogari Yasuhiro , Kubo Masanori , Sato Hideki , Kobayashi Masaru , Goto Yoshiyuki
Published: May 2011

Effects of various antigen-retrieval pretreatment techniques for immunohistochemical detection of Akabane virus antigen were examined with formalin-fixed, paraffin-embedded tissues taken from mice intracerebrally inoculated with the virus. The results indicated that no pretreatment is necessary for the detection of the antigen, and excessive enzymatic pretreatment of sections may lead to false-negative results.
Stability of Vitamin E in Blood and Plasma from Cattle, Sheep, and Pigs
Authors: Mitsioulis Athena , Judson Geoffrey J.
Published: May 2011

The stability of alpha-tocopherol concentrations in sheep, cattle, and pig blood and plasma stored at different temperatures was examined. For all species, the vitamin was stable for at least 6 days in plasma stored at −20 C, 4 C, and 25 C and in blood stored at 4 C and 25 C. For sheep and cattle, the vitamin was stable for at least 6 days in plasma stored at 37 C, but it was unstable in blood from all species stored at 37 C and in pig plasma stored at 37 C.
Bovine Abortions Associated with Bacteroides Fragilis Fetal Infection
Authors: Kraipowich Nicole R. , Morris David L. , Thompson Gayle L. , Mason Gary L.
Published: May 2011

Two Santa Gertrudis cattle from a herd of 105 aborted within a 24-hour period. Bacteroides fragilis was isolated from tissues of each aborted fetus. Histopathologic lesions included placentitis and bronchopneumonia in which gram-negative, rod-shaped organisms were visible. The diagnostic workup failed to reveal other causes of abortion. Anaerobes are rarely implicated in bovine abortions, and no other report was found that described abortion in cattle due to B. fragilis.
Development of a Reverse Transcription-Nested Polymerase Chain Reaction Assay for Differential Diagnosis of Transmissible Gastroenteritis Virus and Porcine Respiratory Coronavirus from Feces and Nasal Swabs of Infected Pigs
Authors: Kim Lomi , Chang Kyeong-Ok , Sestak Karol , Parwani Anil , Saif Linda J.
Published: May 2011

Transmissible gastroenteritis virus (TGEV), a coronavirus, replicates in intestinal enterocytes and causes diarrhea in young pigs. Porcine respiratory coronavirus (PRCV), a spike (S) gene natural deletion mutant of TGEV, has a respiratory tissue tropism and causes mild or subclinical respiratory infections. Conventional antigen-based diagnostic tests fail to differentiate TGEV and PRCV, and a blocking ELISA test to serologically differentiate TGEV/PRCV-infected pigs is conducted on convalescent serum retrospectively after disease outbreaks. A reverse transcription (RT)-nested polymerase chain reaction (PCR) with primers targeted to the S gene deletion region to differentiate TGEV/PRCV was developed. The specificity of the RT-nested PCR was confirmed with reference and recent field strains of TGEV/PRCV, and its sensitivity was analyzed by testing nasal and fecal samples collected from pigs at various days postinoculation (DPI) with TGEV or PRCV. Specific PCR products for TGEV/PRCV were detected only with the homologous reference or field coronaviruses and for 10–14 DPI of pigs with TGEV (feces) or PRCV (nasal samples). The RT-nested PCR assay was more sensitive than antigen-based assays on the basis of duration of virus detection in experimentally infected pigs and was directly applicable to nasal as well as fecal specimens from the field.
Malignant Catarrhal Fever: Polymerase Chain Reaction Survey for Ovine Herpesvirus 2 and Other Persistent Herpesvirus and Retrovirus Infections of Dairy Cattle and Bison
Authors: Collins James K. , Bruns Christa , Vermedahl Tracy L. , Schiebel Anita L. , Jessen Michael T. , Schultheiss Patricia C. , Anderson Gwen M. , Dinsmore R. Page , Callan Robert J. , DeMartini James C.
Published: May 2011

Using a polymerase chain reaction (PCR) test for sequences of ovine herpesvirus 2 (OHV2), this virus was shown to be significantly associated with sheep-associated malignant catarrhal fever (SA-MCF) in terminal cases of disease in 34 cattle and 53 bison. Ovine herpesvirus 2 was not detected in cattle (38) and bison (10) that succumbed to other diseases. Other persistent herpesviruses, retroviruses, and pestivirus, some of which have been previously isolated from cases of SA-MCF, were not associated with the disease. These included bovine herpesvirus 4 (BHV4), bovine lymphotrophic herpesvirus (BLHV), bovine syncytial virus (BSV, also known as bovine spumavirus), bovine immunodeficiency virus (BIV), and bovine viral diarrhea virus (BVDV). A PCR survey for OHV2 in DNA from individual cow's peripheral blood lymphocytes in 4 dairies showed that the 1 dairy that was in close contact to sheep had a prevalence of OHV2 of 21.3%, whereas the 3 other dairies had no OHV2. Prevalence of the other herpesviruses and retroviruses in the dairy cows was variable, ranging from 2% to 51% for BHV4, 52% to 78.7% for BLHV, and 10% to 34% for BSV Bovine lymphotrophic herpesvirus and BSV were also found in a few (1–4 of 21 tested) cases of terminal SA-MCF, but BIV and BVDV were not found in either the dairy cows sampled, or in the cases of SA-MCF. No significant correlation was found between the presence of any 2 viruses (OHV2, BHV4, BLHV, BSV) in the dairy cows or terminal cases of SA-MCF.
The Postmortem Diagnosis of Cholecalciferol Toxicosis: A Novel Approach and Differentiation from Ethylene Glycol Toxicosis
Authors: Rumbeiha Wilson K. , Braselton W. Emmett , Nachreiner Raymond F. , Refsal Kent R.
Published: May 2011

The objectives of this study were to develop a novel approach to postmortem diagnosis of cholecalciferol (CCF) toxicosis in dogs using kidney, bile, and urine samples, and to differentiate CCF from ethylene glycol (EG) toxicosis. To achieve these objectives, specimens collected from 2 previous laboratory studies in which dogs were given a single oral toxic dose of CCF (8.0 mg/kg) were used. For EG toxicosis, historical data from the previous 13 years (1985–1998) were reviewed and confirmed cases of EG toxicosis were selected. The historical data were used to compare trace mineral concentrations, specifically of calcium and phosphorus to differentiate between intoxications caused by CCF from that caused by EG in dogs. Kidneys, bile, and urine from dogs that died of CCF toxicosis were analyzed for 25 monohydroxy vitamin D3 (25(OH)D3) and 1,25 dihydroxy vitamin D3 (1,25(OH)2D3) and compared to known control unexposed dogs. Results of this study show that biliary and renal 25(OH)D3 concentrations and renal calcium to phosphorus ratio are of diagnostic value in dogs exposed to toxic concentrations of CCF. The renal calcium to phosphorus ratio was <0.1 in normal dogs, 0.4–0.9 in dogs that died of CCF toxicosis, and >2.5 in dogs that died of EG toxicosis.
Activated Partial Thromboplastin Time as a Screening Test of Minor or Moderate Coagulation Factor Deficiencies for Canine Plasma: Sensitivity of Different Commercial Reagents
Authors: Mischke Reinhard
Published: May 2011

To determine the sensitivity for detection of coagulation factor deficiencies by commercial reagents for canine plasma, 5 commercial activated partial thromboplastin time (APTT) reagents with different types of contact activator and phospholipid of various origin were examined. Thirty canine plasma samples with minor or moderate deficiencies of coagualition factors that influence the APTT were examined. Significant differences were found for the sensitivity of various reagents, but no correlation was found with the type of contact activator. Following the test instructions provided by the manufacturers, the number of APTT results that were prolonged beyond the reference range varied between 20 and 30 (sensitivity = 0.67–1.00); the number of corresponding results using a standardized test protocol varied between 19 and 28 (sensitivity: 0.63–0.93). The most sensitive reagent contained kaolin as a contact activator and a human placental thromboplastin. The results of this study indicate that the APTT test optimized for human plasma is also a sensitive screening test of the intrinsic system of canine plasma, provided that a suitable reagent is used.
Atypical Actinobacillus Pleuropneumoniae Isolates That Share Antigenic Determinants with Both Serotypes 1 and 7
Authors: Gottschalk M. , Lebrun A. , Lacouture S. , Harel J. , Forget C. , Mittal K. R.
Published: May 2011

In the present study, the characterization of 3 atypical isolates of Actinobacillus pleuropneumoniae is presented. Two isolates (1B and 27E) showed positive reactions in coagglutination, immunodiffusion, and indirect hemagglutination tests for serotypes 1 and 7, whereas the third isolate (26B) reacted with antisera to serotypes 1, 4, and 7. These atypical isolates of A. pleuropneumoniae possessed a capsular polysaccharide (CPS) antigenically related to serotype 1 as well as an O-chain lipopolysaccharide antigenically related to serotype 7 or to serotypes 4 and 7, as shown by the use of monoclonal antibodies. Results of toxin profile and virulence assays for mice and pigs showed them to be more related to A. pleuropneumoniae serotype 7 field isolates. All 3 isolates induced antibodies mainly against serotype 7/4 O-long-chain lipopolysaccharide (LC-LPS) and, to a lesser extent, to the CPS of serotype 1, in experimentally infected pigs. Diagnostic laboratories that use a LC-LPS-based enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of A. pleuropneumoniae infection in swine would probably diagnose herds infected with these atypical isolates as being infected by A. pleuropneumoniae serotypes 7 or 4, whereas those that use a CPS-based ELISA would probably consider them as infected by A. pleuropneumoniae serotype 1.
Fatal Clostridium Botulinum Toxicosis in Eleven Holstein Cattle Fed Round Bale Barley Haylage
Authors: Kelch William J. , Kerr Larry A. , Pringle John K. , Rohrbach Barton W. , Whitlock Robert H.
Published: May 2011

Twenty-two lactating Holstein cattle in Tennessee had clinical signs of intoxication with preformed Clostridium botulinum toxin. These signs included weakness, paralysis of the tongue and chest muscles, abdominal breathing, and, in 11 of the 22 cows, death. Differential diagnoses included hypocalcemia, hypo-magnesemia, carbohydrate overload, and several toxicoses including mycotoxin, lead, nitrate, organophosphate, atropine or atropine-like alkaloid, and botulism. A diagnosis of botulism by the ingestion of preformed C. botulinum type B toxin was made by eliminating these other diseases, by finding C. botulinum type B spores in 3 bales of round bale barley haylage fed to these cattle, and by isolating preformed type B toxin from 1 of the 3 bales. Confirmation of the toxin type was made by demonstrating mouse lethality by intraperitoneal injection of specimen extracts with neutralization by C. botulinum type B antitoxin. The haylage, harvested green and encased in black plastic bags to facilitate fermentation, was presumably contaminated by the botu-linum toxin when fermentation failed to produce enough acid to lower the pH to 4.5, the pH below which C. botulinum growth is inhibited. Farmers and ranchers who use round hay balers to produce haylage should be alert to this potential problem.
Disseminated T-Cell Lymphoma in a Guinea Pig with Bilateral Ocular Involvement
Authors: Steinberg Howard
Published: May 2011

A 2-year-old female shorthair guinea pig was presented to the Veterinary Medical Teaching Hospital, University of Wisconsin–Madison, for evaluation of a unilateral corneal opacity of 1 week duration. Physical examination revealed a markedly thickened right cornea and lymphadenopathy of the submandibular and prescapular lymph nodes. Cytology of a lymph node aspirate was highly suggestive of lymphoma. The animal was humanely euthanized. Postmortem examination revealed a disseminated lymphadenopathy involving the submandibular, anterior cervical, prescapular, bronchial, anterior mediastinal, and mesenteric nodes, and hepatomegaly with accentuation of lobular morphology. The right cornea was dark red, dry and dull, and diffusely thickened, and the globe was exophthalmic. Microscopically, pleomorphic neoplastic lymphoblasts were present in the lymph nodes, spleen, liver, lungs, heart, rhinarium, bone marrow, and kidneys. Bilateral infiltration of the eyes by neoplastic lymphoblasts was noted, which was more extensive on the right. The neoplastic cells stained immunohistochemically as T-lymphocytes using antibodies directed against CD3 antigen.
Hepatic Capillariasis (Capillaria Hepatica) in Porcupines (Erethizon Dorsatum) in Pennsylvania
Authors: Hamir Amir N. , Rupprecht Charles E.
Published: May 2011

Tissues of 53 adult porcupines ( Erethizon dorsatum) from Pennsylvania were obtained for histopathologic examination. Hepatic capillariasis was recorded in 9% of the porcupines. An additional 11% of the liver sections showed lesions that were compatible with migration by Capillaria hepatica. Because only 1 section of the liver per animal was examined microscopically, the documented prevalence of C. hepatica in Pennsylvania is considered conservatively low. However, this condition was subclinical, because none of the infected animals showed clinical signs, and none revealed severe pathologic changes in the affected livers. This seems to be the only report of C. hepatica in porcupines.
Pulmonary Lymphomatoid Granulomatosis in a Cat
Authors: Valentine Beth A. , Blue Julia T. , Zimmer James F. , Yeager Amy E. , McDonough Sean P.
Published: May 2011

Pulmonary lymphomatoid granulomatosis was diagnosed in a 9-year-old castrated male domestic shorthair cat with a history of coughing, lethargy, and anorexia. Radiographic examination revealed multiple pulmonary opacities, consolidation of left lung lobes, and enlarged tracheobronchial lymph nodes. Cytologic examination of impression smears of abnormal pulmonary tissue revealed erythrocytes, lymphocytes, and macrophages, with scattered atypical lymphocytes and binucleate cells. Histopathologic evaluation of abnormal lung tissue revealed multiple, coalescing, densely cellular nodules composed of anaplastic and pleomorphic lymphocytes, with scattered binucleate and multinucleate cells. Marked infiltration and effacement of bronchiolar and vascular smooth muscle were present. These features are characteristic of lymphomatoid granulomatosis. To the authors' knowledge, this is the first report of pulmonary lymphomatoid granulomatosis in a cat.
Cardiomyopathy in Captive African Hedgehogs (Atelerix Albiventris)
Authors: Raymond James T. , Garner Michael M.
Published: May 2011

From 1994 to 1999, 16 captive African hedgehogs ( Atelerix albiventris), from among 42 necropsy cases, were diagnosed with cardiomyopathy. The incidence of cardiomyopathy in this study population was 38%. Fourteen of 16 hedgehogs with cardiomyopathy were males and all hedgehogs were adult (>1 year old). Nine hedgehogs exhibited 1 or more of the following clinical signs before death: heart murmur, lethargy, icterus, moist rales, anorexia, dyspnea, dehydration, and weight loss. The remaining 7 hedgehogs died without premonitory clinical signs. Gross findings were cardiomegaly (6 cases), hepatomegaly (5 cases), pulmonary edema (5 cases), pulmonary congestion (4 cases), hydrothorax (3 cases), pulmonary infarct (1 case), renal infarcts (1 case), ascites (1 case), and 5 cases showed no changes. Histologic lesions were found mainly within the left ventricular myocardium and consisted primarily of myodegeneration, myonecrosis, atrophy, hypertrophy, and disarray of myofibers. All hedgehogs with cardiomyopathy had myocardial fibrosis, myocardial edema, or both. Other common histopathologic findings were acute and chronic passive congestion of the lungs, acute passive congestion of the liver, renal tubular necrosis, vascular thrombosis, splenic extramedullary hematopoiesis, and hepatic lipidosis. This is the first report of cardiomyopathy in African hedgehogs.
Ossifying Fibroma in a Llama
Authors: McCauley Charles T. , Campbell Gregory A. , Cummings Connie A. , Drost Wm. Tod
Published: May 2011

A 4.5-year-old llama was admitted for evaluation of a firm mass rostral and ventral to the medial canthus of the left eye. Mucopurulent nasal discharge and absence of airflow through the left nostril were noted. Radiographs of the skull revealed a sharply demarcated soft tissue mass with faint mineralization. Endoscopy of the nasal passages revealed a mucosa-covered mass originating in the area of the second premolar, extending to the edge of the soft palate, and obstructing the airway. Examination of the oral cavity revealed a missing second molar and a mass protruding 2-cm from the empty alveolus. An ossifying fibroma, a previously unre-ported tumor in llamas, was diagnosed at postmortem examination.
Production and Evaluation Criteria of Specific Monoclonal Antibodies to the Hemagglutinin of the H7N2 Subtype of Avian Influenza Virus
Authors: Wang X. , Castro A. E. , Castro M. D. , Lu H. , Weinstock D. , Soyster N. , Scheuchenzuber W. , Perdue M.
Published: May 2011

To enhance the rapidity in diagnosing the spread of avian influenza virus (AIV) in chicken layer flocks, studies were initiated to develop more sensitive and specific immunological and molecular methods for the detection of AIV. In this study, the purification of the hemagglutinin protein (H) from field isolates of H7N2, the production of monoclonal antibodies (MAbs), and their evaluation as diagnostic reagents are reported. Hybridomas were generated by fusion of SP2/0-Ag14 myelomas and spleen cells from immunized mice. Hybridomas secreting antibodies specific for the H protein were assayed by an ELISA and cloned using limiting dilution. The MAbs produced were characterized by hemagglutination inhibition (HI), immunohistochemistry (IHC), indirect fluorescent antibody assay (IFA), Western blots, and IFA flow cytometry using various AIV subtypes (i.e., H4N2, H5N3, H7N2). Of the various MAbs assayed, 6 had consistent and reproducible results in each of the assays used. The results obtained in this investigation enhanced the usage of the MAbs to viral H protein in the surveillance of AIV in chickens.