bluuebunny/crossref_metadata_2025 huggingface dataset:
Autosomal Recessive Severe Combined Immunodeficiency of Jack Russell Terriers
Authors: Bell Thomas G. , Butler Kelly L. , Sill Helen B. , Stickle Julia E. , Ramos-Vara Jose A. , Dark Michael J.
Published: May 2011

Because of unexplained mortality among 33 sibling offspring of a single pair of dogs, a family of Jack Russell Terriers was investigated. Twelve pups, 5 male and 7 female, died between 8 and 14 weeks of age. Six of those animals died in the field within 50 hours following vaccination with modified live vaccines. Subsequent histopathologic examination revealed the absence of splenic white pulp in 4 dogs and hepatic inclusions diagnostic for adenoviral infection in 2 dogs. Two additional litters yielded 2 pups with the same splenic and hepatic lesions. These observations led to a detailed study of 7 siblings whelped specifically for this investigation. Four of these 7 siblings had a profound lymphopenia and a decrease in serum immunoglobulins. Six of these dogs were necropsied at 7 weeks of age, and 4 of them had marked hypoplasia of all lymphoid tissue. The affected pups had an 86% decrease in mean thymic weight, with poor corticomedullary differentiation, and very few CD3-positive (T cell) thymocytes were detected immunohistochemically. However, the affected thymic tissue stained intensely with a immunochemical stain for cytokeratin. The other affected lymphoid tissues were identified histologically only by stromal architectural characteristics. Lymph nodes lacked both CD3 and CD79a (B cell) positive cells. The analyzed breeding data were consistent with an autosomal recessive mode of inheritance. This canine severe combined immunodeficiency has immunologic and pathologic features similar to those observed in immunodeficient C.B-17 mice and Arabian horses.
Evaluation and Extension of the Cusum Technique with an Application to Salmonella Surveillance
Authors: Carpenter T. E.
Published: May 2011

The cumulative sum (cusum) technique was examined for its use in a disease surveillance system for detecting temporal clusters of events. Optimal technique parameters were derived for scenarios not previously considered. Simulation modeling produced results that evaluated deviations from predefined rate increases. The cusum technique was less prone to false alarms and more efficient at detecting large rate increases than previously reported. As demonstrated using data obtained from a Salmonella surveillance system operated by a state animal diagnostic laboratory system, the cusum technique could provide early warning of an epidemic problem.
Values of Urine Specific Gravity for Thoroughbred Horses Treated with Furosemide Prior to Racing Compared with Untreated Horses
Authors: Cohen Noah D. , Peck Kenneth E. , Smith Sarah A. , Ray Allen C.
Published: May 2011

The distribution of specific gravity values for 2,599 urine samples collected from racing Thoroughbred horses that were known to have received furosemide prior to racing was compared with that for 1,669 urine samples from racing Thoroughbred horses that reportedly had not received furosemide. Values of specific gravity for furosemide-treated horses were significantly lower ( P < 0.001) than those for horses that had not received furosemide, and the proportion of horses with urine specific gravity either <1.010 or <1.012 was significantly greater ( P < 0.001) among the furosemide-treated horses. These data indicate that evaluation of urine specific gravity would be a useful component of drug testing programs for regulation of furosemide use.
Simultaneous Detection of Porcine Circovirus 2 and Porcine Parvovirus in Naturally and Experimentally Coinfected Pigs by Double in Situ Hybridization
Authors: Kim Junghyun , Chae Chanhee
Published: May 2011

A technique for double in situ hybridization to simultaneously detect porcine circovirus 2 (PCV2) and porcine parvovirus (PPV) in the same tissue section was developed and applied to lymph node and spleen from 8 pigs experimentally coinfected with PCV2 and PPV and 20 pigs with naturally occurring postweaning multisystemic wasting syndrome. For double labeling studies, the tissue samples were processed sequentially, first for PPV in situ hybridization using a digoxigenin-labeled probe and then for PCV2 in situ hybridization using a biotinylated probe. Positive cells contained reaction products for PCV2 and PPV, respectively. Both PCV2 DNA and PPV DNA were observed mainly in the cytoplasm but occasionally in the nucleus. With double in situ hybridization, both PCV2 DNA and PPV DNA were simultaneously detected in lymph node and spleen. This double labeling technique for the detection of PCV2 and PPV is suitable both for pathogenesis studies and for diagnostic applications.
Comparison of the Serum Neutralization Test and a Competitive Enzyme-Linked Immunosorbent Assay for the Detection of Antibodies to Vesicular Stomatitis Virus New Jersey and Vesicular Stomatitis Virus Indiana
Authors: Alvarado Juan Francisco , Dolz Gaby , Herrero Marco V. , McCluskey Brian , Salman Mo
Published: May 2011

A competitive enzyme-linked immunosorbent assay (C-ELISA) for the detection of antibodies against vesicular stomatitis virus New Jersey (VSV-NJ) and vesicular stomatitis virus Indiana (VSV-IN) was compared with the serum neutralization test (SNT) using 1,106 serum samples obtained from dairy cattle on sentinel study farms in the Poás region of Costa Rica. Kappa coefficients between the C-ELISA and the SNT were 0.8871 (95% confidence interval [CI]: 0.8587–0.9155) and 0.6912 (95% CI: 0.6246–0.7577) for the VSV-NJ and VSV-IN tests, respectively. These results indicate good to excellent agreement between the 2 tests under these conditions.
Dermal Melanoma with Schwannoma-Like Differentiation in a Brown Bullhead Catfish (Ictalurus Nebulosus)
Authors: Sakamoto Kaori , White M. Randall
Published: May 2011

A dermal melanoma with histologic similarities to mammalian melanocytic schwannomas was diagnosed in a wild-caught brown bullhead catfish ( Ictalurus nebulosus). The diagnosis was based on cytologic, histopathologic, immunohistochemical, and ultrastructural findings. The neoplasm protruded from the cutaneous surface of the dorsal midline immediately caudal to the dorsal fin, was diffusely black and focally ulcerated, and was attached to the underlying skin by a broad-based stalk. Cytologically, the tumor was composed of a monomorphic population of melanophores, the melanin-producing and storing cells within the dermis and epidermis of fish that are partially responsible for rapid color changes. Histopathologic examination of the neoplasm revealed an unencapsulated, well-circumscribed, moderately cellular neoplasm composed of 2 distinct cell populations: spindle cells arranged in a “herringbone” pattern and numerous melanophores. The spindle cells had scant bipolar eosinophilic cytoplasm, with small centrally located vesicular nuclei; nucleoli were not seen. The histologic appearance was similar to that described for mammalian melanocytic schwannomas. Immunohistochemically, the spindle cells exhibited positive cytoplasmic staining for S-100 protein but were negative for vimentin, neurofilament protein, and glial fibrillary acidic protein. Ultrastructurally, the tumor consisted of neoplastic spindle cells with rudimentary cell junctions, actin bundles, and few melanosomes and melanophores with abundant intracytoplasmic melanosomes.
In Situ Detection of Cellular and Abnormal Isoforms of Prion Protein in Brains of Cattle with Bovine Spongiform Encephalopathy and Sheep with Scrapie by Use of a Histoblot Technique
Authors: Kimura Kumiko M. , Yokoyama Takashi , Haritani Makoto , Narita Minoru , Belleby Peter , Smith Julie , Spencer Yvonne I.
Published: May 2011

To detect prion protein, brains from 5 cattle naturally affected with bovine spongiform encephalopathy (BSE) and 3 sheep naturally affected with scrapie were examined and compared with brains of normal cattle and sheep using a histoblot technique. The technique enabled the in situ distinctive detection of the cellular (PrPC) and abnormal (PrPSc) isoforms of the prion protein. In BSE- or scrapie-affected brains, the PrPC signal decreased, especially in those areas where the PrPSc signal was detected.
Evaluation of a Test for Clostridium Difficile Toxins A and B for the Diagnosis of Neonatal Swine Enteritis
Authors: Post Karen W. , Jost B. Helen , Songer J. Glenn
Published: May 2011

A commercially available 1-hour enzyme immunoassay (EIA) for detecting the presence of Clostridium difficile toxins A and B was evaluated for use in diagnosis of C. difficile infections in neonatal swine. This test was compared with a tissue culture cytotoxicity assay, which is considered to be the reference standard for the detection of C. difficile toxins. Twenty-seven samples of colonic contents and 23 fecal samples were collected from freshly euthanized neonatal swine with a history of scours. Of the 50 specimens tested, 20 were positive by the EIA test and tissue culture and 24 were negative by both tests, for an overall correlation of 88%. The sensitivity and specificity of the EIA were 91% and 86%, respectively, and the positive and negative predictive values were 84% and 86%, respectively. The EIA test is considered suitable as an aid for the diagnosis of C. difficile enteritis because of the high correlation between EIA results and those of the tissue culture cytotoxicity assay.
Endocarditis Associated with Escherichia Coli in a Sea Lion (Zalophus Californianus)
Authors: Kim J.-H. , Lee J.-K. , Yoo H.-S. , Shin N.-R. , Shin N.-S. , Lee K.-H. , Kim D.-Y.
Published: May 2011

Endocarditis associated with Escherichia coli was diagnosed in a 2-year-old male California sea lion ( Zalophus californianus). The diagnosis was based on light microscopic examination and bacterial isolation from the valvular lesion. This is the first case of bacterial endocarditis reported in a sea lion.
Solitary Dermal Leiomyosarcomas in 12 Ferrets
Authors: Mikaelian Igor , Garner Michael M.
Published: May 2011

Twelve 3–6-year-old ferrets (8 males, 3 females, 1 unknown) were presented with single cutaneous nodules. These dermal tumors were characterized histologically by nodular proliferation of neoplastic smooth muscle fibers with marked anisokaryosis and a mitotic rate of >2 mitoses per 10 high-power fields. Neoplastic cells stained strongly for vimentin in all tumors and for smooth muscle actin and desmin in all but 1 tumor. Histologic and immunohistochemical findings suggested a diagnosis of piloleiomyosarcoma for these tumors. Excision was curative in all animals available for follow-up. However, 3 of 5 animals developed adrenal disease within 7 months after removal of the dermal leiomyosarcoma.
A Survey of Agents Associated with Neonatal Diarrhea in Iowa Swine Including Clostridium Difficile and Porcine Reproductive and Respiratory Syndrome Virus
Authors: Yaeger Michael , Funk Nathan , Hoffman Lorraine
Published: May 2011

This survey was undertaken to determine the relative frequency of agents that are currently associated with neonatal diarrhea in swine, including Clostridium difficile and porcine reproductive and respiratory syndrome virus (PRRSV). The subjects for this study were the first 100 live 1–7-day-old piglets submitted to the Iowa State University Veterinary Diagnostic Laboratory with a clinical signalment of diarrhea, beginning on January 1, 2000. The evaluation of each pig included bacterial culture of a section of ileum, 2 sections of jejunum, and a single section of colon; a fluorescent antibody test (FAT) or immunohistochemistry (IHC) for transmissible gastroenteritis virus (TGEV); ELISA's for rotavirus and C. difficile toxins; IHC for PRRSV; and microscopic examination of ileum, midjejunum, spiral colon, liver, spleen, and lung. Survey results demonstrate a decline in the relative number of diagnoses of TGEV, Escherichia coli, and Clostridium perfringens type C compared with retrospective data. The combined case frequency rate for these 3 pathogens dropped from 70% in 1988 to 21% in 2000. This survey also demonstrated the emergence of C. difficile as an important pathogen of neonatal swine. Clostridium difficle toxin was detected in the colon contents of 29% of the piglets, and at least 1 toxin-positive animal was identified in 55% of the cases. All 29 C. difficile toxin-positive piglets had mesocolonic edema, and colitis was observed in 21 of 29 toxin-positive animals. PRRSV-positive macrophages were detected in the lamina propria of intestinal villi by IHC in 10 piglets with diarrhea. In 6 of these cases, PRRSV was the only pathogen detected. Gross and microscopic lung lesions were not a reliable indicator of PRRSV infection in these neonatal pigs with diarrhea. The addition of tests for C. difficile and PRRSV to a routine neonatal diarrhea diagnostic protocol resulted in a significant increase in the diagnostic success rate on both individual animal and case bases.
Detection of Respiratory and Enteric Shedding of Bovine Coronaviruses in Cattle in an Ohio Feedlot
Authors: Hasoksuz Mustafa , Hoet Armando E. , Loerch Steven C. , Wittum Thomas E. , Nielsen Paul R. , Saif Linda J.
Published: May 2011

Recently, bovine coronavirus (BCV) has been isolated from new cattle arrivals to feedlots, but the association between respiratory and enteric infections with BCV in feedlot cattle remains uncertain. Fecal and nasal swab samples from 85 Ohio Agricultural Research and Development Center (OARDC) feedlot cattle averaging 7 months of age were collected at arrival (0) and at 4, 7, 14, and 21 days postarrival (DPA). An antigen capture enzyme-linked immunosorbent assay (ELISA) was used to detect concurrent shedding of BCV in fecal and nasal samples. All samples ELISA positive for BCV were matched with an equal number of BCV ELISA-negative samples and analyzed by reverse transcription-polymerase chain reaction (RT-PCR) of the N gene. Paired sera were collected at arrival and 21 DPA and tested for antibodies to BCV using an indirect ELISA. Information on clinical signs, treatments provided, and cattle weights were collected. The overall rates of BCV nasal and fecal shedding were 48% (41/85) and 53% (45/85) by ELISA and 84% (71/85) and 96% (82/85) by RT-PCR, respectively. The peak of BCV nasal and fecal shedding occurred at 4 DPA. Thirty-two cattle (38%) showed concurrent enteric and nasal shedding detected by both tests. Eleven percent of cattle had antibody titers against BCV at 0 DPA and 91% of cattle seroconverted to BCV by 21 DPA. The BCV fecal and nasal shedding detected by ELISA and RT-PCR were statistically correlated with ELISA antibody seroconversion ( P < 0.0001); however, BCV fecal and nasal shedding were not significantly related to clinical signs. Seroconversion to BCV was inversely related to average daily weight gains ( P < 0.06). Twenty-eight respiratory and 7 enteric BCV strains were isolated from nasal and fecal samples of 32 cattle in HRT-18 cell cultures. These findings confirm the presence of enteric and respiratory BCV infections in feedlot calves. Further studies are needed to elucidate the differences between enteric and respiratory strains of BCV and their role in the bovine respiratory disease complex of feedlot cattle.
A Case Report of Sporadic Ovine Listerial Menigoencephalitis in Iowa with an Overview of Livestock and Human Cases
Authors: Wesley Irene V. , Larson David J. , Harmon Karen M. , Luchansky John B. , Schwartz Ann Ramos
Published: May 2011

A case of ovine listeriosis was examined in a flock of sheep. The index case was a male lamb, which was part of a flock of 85 sheep located in central Iowa. Because the sheep were raised on a premise where soybean sprouts were also cultivated for the organic foods market, the potential of a public health concern was addressed. To identify the source of contaminations, clinical and environmental samples were cultured for Listeria monocytogenes. Isolates were serotyped and analyzed using pulsed-field gel electrophoresis (PFGE). Listeria monocytogenes (serotype 1) was recovered from the brain of a male lamb with clinical signs of listerial encephalitis. Isolates of serotypes 1 and 4 were also cultured from feces of clinically healthy lambs, compost piles, and soybean cleanings. By PFGE, the clinical isolate was distinctly different from the other isolates. Environmental isolates were identified as L. monocytogenes serotypes 1 and 4. However, by PFGE, none matched the profile of the single clinical isolate. Thus, the ultimate source of contamination is unknown.
Lack of Detection of Feline Leukemia and Feline Sarcoma Viruses in Diffuse Iris Melanomas of Cats by Immunohistochemistry and Polymerase Chain Reaction
Authors: Cullen Cheryl L. , Haines Deborah M. , Jackson Marion L. , Grahn Bruce H.
Published: May 2011

Diffuse iris melanoma was confirmed by light-microscopic examination in 10 formalin-fixed, paraffin-embedded globes from 10 cats. To determine if feline leukemia virus or a replication defective feline leukemia virus, feline sarcoma virus, was present in these anterior uveal melanomas, immunohistochemistry and polymerase chain reaction for feline leukemia virus were utilized. Immunohistochemical staining for feline leukemia virus glycoprotein 70 was performed on all 10 tumors using an avidin–biotin complex technique. The DNA was extracted from each specimen and a 166-base pair region of the feline leukemia virus long terminal repeat was targeted by polymerase chain reaction. Immunohistochemical staining for feline leukemia virus glycoprotein 70 and polymerase chain reaction amplification of a feline leukemia virus long terminal repeat region were negative in all cases. Feline leukemia virus/feline sarcoma virus was not detected in any neoplasms and therefore was unlikely to play a role in the tumorigenesis of these feline diffuse iris melanomas.
Restriction Fragment Length Polymorphism of Porcine Reproductive and Respiratory Syndrome Viruses Recovered from Ontario Farms, 1998–2000
Authors: Cai Hugh Y. , Alexander Hazel , Carman Susy , Lloyd Dara , Josephson Gaylan , Maxie M. Grant
Published: May 2011

From January 1998 to July 2000, 2,456 clinical samples, including lung, tonsil, lymph node, and serum, from 760 cases submitted to the Animal Health Laboratory, Ontario, Canada, were tested for porcine reproductive and respiratory syndrome viruses (PRRSV) using reverse transcriptase polymerase chain reaction (RT-PCR) and RT-PCR product restriction fragment length polymorphism (RFLP) analysis. A total of 516 samples from 284 cases were RT-PCR positive for the PRRSV open reading frame (ORF) 7 sequence. The RT-PCR RFLP typing assay was performed using 2 different sets of primers, amplifying 716 or 933 base pairs of ORF 4, 5, and 6 of PRRSV. Samples from 254 cases were typeable, yielding 34 different RFLP types. Of these, 164 cases had 32 different RFLP types of field or intermediate strains, 86 had a pattern similar to a commercial PRRSV vaccine or VR 2332 strain of the virus, 4 had a RFLP type shared by another commercial vaccine and a field strain. In 4 cases, 2 different RFLP types were identified from tissues from different pigs that were submitted at the same time from the same farm. Of the 195 farms that submitted PRRSV PCR-positive samples, 48 submitted samples on more than 1 occasion during the specified time frame. In 23 of those 48 farms, RFLP patterns of PRRSV differed between submissions, whereas in the other 25 farms, the RFLP pattern remained unchanged. There were 34 different PRRSV patterns identified from 236 cases using the primer set amplifying 716 base pairs of PRRSV. There were 18 cases, consisting of 9 different patterns, typeable only by using the primers amplifying a 933-base pair fragment of the virus.
A Single Subtype of Avian Pneumovirus Circulates among Minnesota Turkey Flocks
Authors: Dar Arshud M. , Munir Shirin , Goyal Sagar M. , Kapur Vivek
Published: May 2011

The recent emergence of avian pneumovirus (APV) infection among US turkey flocks has resulted in a major economic threat to the turkey industry. In order to elucidate the molecular epidemiology of APV, comparative sequence analysis of the fusion (F) protein gene of APV was performed for 3 cell culture-adapted isolates and 10 APV positive clinical samples recovered from US turkey flocks. Relatively modest levels of nucleotide and amino acid sequence divergence were identified, suggesting the prevalence of a single lineage of APV among US turkey flocks. Additionally, numerous polymorphisms were identified that were only represented in the clinical samples but not in the in vitro propagated isolates of APV. Phylogenetic analyses confirm that the subtype of APV circulating in the upper Midwestern United States is evolutionarily related to, but distinct from, European APV subgroups A and B. Overall, the results of the present investigation suggest that there has been only a single recent introduction of APV into US turkey populations in the upper Midwestern United States.
Tissue Distribution of Avian Infectious Bronchitis Virus following in Ovo Inoculation of Chicken Embryos Examined by in Situ Hybridization with Antisense Digoxigenin-Labeled Universal Riboprobe
Authors: Lee Chang-Won , Brown Corrie , Jackwood Mark W.
Published: May 2011

Chicken embryos were inoculated with 8 different strains of infectious bronchitis virus (IBV) representing 7 different serotypes at 17 days of embryonation. At 2 and 5 days postinfection (dpi), tissues were collected for in situ hybridization using an antisense digoxigenin-labeled riboprobe corresponding to the sequence of the mRNA coding for the membrane protein. Extensive antigen staining in the cytoplasm of epithelial cells in the trachea, lung, bursa, and intestine was detected at 2 dpi with all 8 strains of IBV. At 5 dpi, little or no positive staining was observed in these tissues. However, tubular cells of the kidney showed multifocal positive staining with the Wolgemuth strain-, Gray strain-, JMK strain-, and Mass41 strain-infected chickens. No viral RNA was detected in the spleen at any time point. The results demonstrated strict epitheliotropic nature and wide tissue tropism of strains of IBV in the chicken embryo and the universality of our riboprobe. In situ hybridization with this probe will be useful for understanding the tissue tropism and the pathogenesis of IBV in vivo.
Hereditary Sterilizing Short-Tail Sperm Defect in Finnish Yorkshire Boars
Authors: Sukura Antti , Mäkipää Raili , Vierula Matti , Rodriguez-Martinez Heriberto , Sundbäck Pernilla , Andersson Magnus
Published: May 2011

A new infertility syndrome has recently been described in Finnish Yorkshire boars. Typical for the syndrome is total akinesia and severe tail malformation of the spermatozoa. Morphometric analysis was performed on semen smears from 20 affected and 18 control boars and on testicular tissue sections from 5 affected and 4 control boars. Semen morphometry revealed that, in affected boars, the length of the sperm tails was only 33% of that of the controls (15.4 μm vs. 47.0 μm, P < 0.0001). Typical for the spermatozoa of affected boars was also an abundant frequency of proximal cytoplasmic droplets (72.4% vs. 6.9%, P < 0.0001), whereas no major sperm-head abnormalities were recorded. In the testicular tissue samples, viewed at light microscopic level, the volume densities of seminiferous tubules or interstitium did not differ. The most characteristic change in the seminiferous epithelium of the affected boars was a reduced number of elongated spermatids. Densities of Sertoli cells and Leydig cells between affected and control boars did not differ. The ultrastructure of testicular tissue from affected boars showed severe alterations in the assembly of the midpiece and tail of the spermatozoa. As well, a typical finding in the seminiferous epithelium of affected boars was conspicuous deposition of lipid droplets. The pathogenesis of this syndrome severely affects spermiogenesis and motility. Spermatozoa have malformed, short tails, which never become motile. This syndrome is not manifested in the structure or function of other ciliated cells in the affected animals.
Absence of Bovine Leukosis Virus in Semen of Seropositive Bulls
Authors: Choi K. Yeon , Monke Don , Stott Jeffrey L.
Published: May 2011

A polymerase chain reaction (PCR)-based detection system was established to identify the presence of bovine leukosis virus (BLV) DNA in bovine semen. Seventy-nine bulls were included in the study. Serum, peripheral blood leukocytes, and semen were collected from each of the 79 bulls. The BLV-specific antibody was detected in serum by agar gel immunodiffusion and viral DNA in blood and semen by PCR. Serologically, 29 of the 79 bulls were BLV positive. Twenty-seven of the 29 seropositive bulls and 1 of the seronegative bulls had BLV DNA in peripheral blood leukocytes. All 79 bulls tested PCR negative for the presence of BLV in semen. This data is strong evidence that properly collected semen from BLV seropositive bulls will not contribute to dissemination of this viral infection.
Vitamin E and Selenium Concentrations in Livers of Pigs Diagnosed with Mulberry Heart Disease
Authors: Pallarés Francisco J. , Yaeger Michael J. , Janke Bruce H. , Fernandez Guillermo , Halbur Patrick G.
Published: May 2011

During a 2-year period from January 1, 1999, to December 31, 2000, 77 diagnoses of mulberry heart disease (MHD) were documented at the Iowa State University Veterinary Diagnostic Laboratory. Mean (±SD) liver vitamin E concentrations were lower ( P < 0.05) in pigs with MHD (3.12 ±1.12 ppm, wet weight) than in pigs that died of causes other than MHD (4.80 ± 3.2 ppm, wet weight). The majority of the pigs affected with MHD ranged in age from 3 to 7 weeks. Statistical influence of age was found on the concentration of vitamin E ( P < 0.01) but not on concentration of selenium in liver in pigs with MHD. Concentrations of vitamin E below 2 ppm were considered deficient. Hepatic vitamin E concentrations below 2 ppm were measured in 25% of the pigs with gross and microscopic lesions of MHD. In contrast, liver selenium concentrations were adequate in all pigs.
Mycotic Rumenitis in American Bison (Bison Bison)
Authors: Dyer N. W. , Newell T. K.
Published: May 2011

Necropsies were performed on 2 American bison ( Bison bison) cows, 1 of which died acutely and the other that died after a week of illness. Gross and microscopic lesions were consistent with severe mycotic infection of the forestomachs. Both animals had been abruptly placed on a breeder ration 1 month after calving, and had developed acidosis and subsequent fungal invasion of tissues. History and lesions in this case indicate that bison are susceptible to rumen acidosis and its sequelae.
Thymic Hematoma in Juvenile Dogs Associated with Anticoagulant Rodenticide Toxicosis
Authors: Liggett Alan D. , Thompson Larry J. , Frazier Ken S. , Styer Eloise L. , Sangster Lowell T.
Published: May 2011

Ten cases of thymic hematoma in young dogs (9–24 weeks of age) were reviewed. Anticoagulant rodenticide toxicosis was confirmed in 5 cases. Histologically, hemorrhage caused variable expansion of thymic lobules and interlobular septa. The medulla appeared to be the primary site of hemorrhage. In areas of severe hemorrhage, normal lobular architecture was lost and lymphocytes were admixed in the hemorrhagic exudate. Vasculitis, necrosis of capillaries, and degeneration of the capsule were observed in infarcted areas. In 2 cases, angiofibroplasia indicated a longer interval between onset of thymic hemorrhage and death. The lesions are similar to those in 5 cases of idiopathic thymic hemorrhage. Appropriate samples were not available for anticoagulant rodenticide analysis in 3 of these 5 idiopathic cases. Lesions in confirmed cases of anticoagulant rodenticide toxicosis also are compatible with published descriptions of idiopathic and spontaneous thymic hemorrhage, but are inconsistent with normal thymic involution. Analysis for anticoagulant rodenticides is indicated in cases of thymic hematoma when an obvious cause is not detected at necropsy.
Evaluation of Result Variability with a Commercial Johne's Disease Enzyme-Linked Immunosorbent Assay Kit and Repeat Testing of Samples
Authors: Adaska John M. , Muñoz-Zanzi Claudia A. , Hietala Sharon K.
Published: May 2011

Two hundred one serum samples from individual dairy cows with a range of results on initial testing with a commercial Johne's disease enzyme-linked immunosorbent assay (ELISA) kit were repeat tested 5 times in each of 2 laboratories with kits produced by the same manufacturer. The results for the samples with all 10 replicates showed that the values for individual samples often had a coefficient of variation greater than 20%. As expected, the standard deviation for the results increased as the average value increased and the coefficient of variation was greater in samples with low mean values. The different lots of the commercial ELISA kit used in this study had a significant effect on both the optical density and the calculated sample to positive (S/P) ratio for test replicates. Based on the variability detected in S/P ratios of replicate samples, application of a single cutoff point to interpret individual test results as positive or negative for antibodies to Mycobacterium avium subspecies paratuberculosis could result in inconsistent classification of animals as positive or negative for Johne's disease. Such inconsistency in test interpretation leads to frustration in large animal veterinarians or producers trying to make management decisions based on individual test results. Instead of dichotomizing the test results as positive or negative based on a single cutoff value, reporting numerical values and supplying a classification scheme that includes a suspect category reflecting the uncertainty inherent in the test is recommended to provide more reliable result interpretation.
Evaluation of an Immunochromatography Strip Assay for the Detection of Salmonella Sp. from Poultry
Authors: Bautista D. A. , Elankumaran S. , Arking J. A. , Heckert R. A.
Published: May 2011

The present study was conducted to evaluate the sensitivity and specificity of an immunochromatography-based diagnostic kit for Salmonella. The analytical sensitivity of the test when using pure colonies of different Salmonella species was in the range of 1 × 104 to 1 × 105 colony-forming units per milliliter. The strip detected 19 of 22 strains of Salmonella spp. but failed to detect S. worthington, S. choleraesuis var kunzendorf, and S. johannesburg. The strip did not detect 27 different enteric bacteria, including Escherichia coli O157:H7, Campylobacter jejuni, Shigella sonnei, and Vibrio parahaemolyticus. In direct testing of feces ( n = 66) from chickens infected with Salmonella typhimurium, the strip had a sensitivity of 12.3% and a specificity of 100%. Evaluation of the strip assay ( n = 510) after sample pre-enrichment in 2% buffered peptone water (BPW) yielded a sensitivity of 93.8% and specificity of 89% when compared to isolation and identification with xylose-lysine-tergitol 4 (XLT4) selective plating media. Subsequent enrichment in Hajna tetrathionate (TT) broth yielded a higher sensitivity (94.7%) and specificity (96.8%). The agreement (kappa) between the strip test and isolation was 0.004 in direct fecal testing, 0.82 in BPW, and 0.89 in TT broth. The assay could detect Salmonella sp. as early as 18–48 hours during pre-enrichment and enrichment compared to isolation on XLT4, which required an overnight incubation step for the presumptive isolation and identification of Salmonella.
Bacterial Pathogens Isolated from Cultured Bullfrogs (Rana Castesbeiana)
Authors: Mauel Michael J. , Miller Debra L. , Frazier Kendall S. , Hines Murray E.
Published: May 2011

A commercial bullfrog ( Rana castesbeiana) operation in south Georgia had multiple epizootics of systemic bacterial infections over a 3-year period, 1998–2000. A number of potential pathogens ( Aeromonas hydrophila, Chryseobacterium ( Flavobacterium) meningosepticum, Chryseobacterium ( Flavobacterium) indolgenes, Edwardsiella tarda, Citrobacter freundii, Pseudomonas spp., and ( Streptococcus iniae) were isolated from various tissues. Clinically, frogs demonstrated acute onset of torticolis, stupor, and indifference to stimuli. Cutaneous hyperemia, subcutaneous and muscular hemorrhage, and peripheral edema were consistent gross findings. Histologically, clusters of lymphocytes, monocytes, and occasional acidophiles with scattered granulomas occurred in liver, kidney, and spleen. This is the first report of S. inae and C. meningosepticum as potential disease agents in R. castesbeiana. These findings suggest that a variety of bacteria may be associated with redleg and that culture results must be obtained for accurate diagnosis.
A Comparison of Polymerase Chain Reaction with and without RNA Extraction and Virus Isolation for Detection of Bovine Viral Diarrhea Virus in Young Calves
Authors: Deregt D. , Carman P. S. , Clark R. M. , Burton K. M. , Olson W. O. , Gilbert S. A.
Published: May 2011

Previously, the authors described a multiplex reverse transcriptase–polymerase chain reaction (PCR) assay for detection and typing of bovine viral diarrhea virus (BVDV) from blood of persistently infected (PI) cattle that could be used with or without RNA extraction. In the present study, the PCR assay was evaluated for its ability to detect BVDV in young calves as a screening tool for detection of persistent infections. Both methods, PCR after RNA extraction (rPCR) and the direct method without RNA extraction (dPCR) were applied and compared with virus isolation (VI) with diagnostic specimens. From 450 whole blood samples from Ontario calves, 47 and 39 samples were positive by rPCR and VI, respectively. From the 47 samples positive by rPCR, 45 (96%) also were positive by dPCR when samples were tested both undiluted and diluted 1:10. In comparison to VI, the relative sensitivities of both PCR assays were 100%. Examination of the results indicates that both PCR assays can be used for screening calves for persistent infection with BVDV.
Enteric Coronavirus Infection in a Juvenile Dromedary (Camelus Dromedarius)
Authors: Wünschmann Arno , Frank Rodney , Pomeroy Kem , Kapil Sanjay
Published: May 2011

A case of an enteric coronavirus infection in a 6-week-old dromedary calf is described. The animal had diarrhea for 5 days and died despite symptomatic treatment. Numerous viral particles, approximately 140 nm in diameter, with club-like projections were detected in the feces by electron microscopy. These characteristics were consistent with a coronavirus. Immunohistochemical reactivity with 2 antigenic group II coronavirus-specific antibodies confirmed the presence of viral antigen in colonic epithelial cells. The death of the animal was attributed to a neutrophilic and emphysematous colitis that likely was caused by an infection with a Clostridium sp.
Resistance of Domestic Cats to a US Sheep Scrapie Agent by Intracerebral Route
Authors: Hamir Amir N. , Clark Wilber W. , Sutton Diane L. , Miller Janice M. , Stack Mick J. , Chaplin Melanie J. , Jenny Allen L.
Published: May 2011

Feline spongiform encephalopathy (FSE) is thought to have resulted from consumption of food contaminated with bovine spongiform encephalopathy and the latter is believed to result from the consumption of food contaminated with scrapie. However, no direct experimental documentation exists to indicate that the scrapie agent is capable of amplifying in cats, and, therefore, crossing the species barrier. During 1979, 6 cats ranging in age from 3.5 to 18 months were intracerebrally inoculated with sheep scrapie (inoculum G-639-PP) and were observed for an extended period. Inoculated cats did not develop neurologic disease, and microscopic lesions of spongiform encephalopathy were not evident. Immunohistochemistry and Western blot techniques failed to detect the abnormal form of prion protein (PrPres). These results indicate that the sheep scrapie agent (G-639-PP) used in this study was not capable of amplifying in cats and therefore was unable to cross the species barrier to produce FSE.
Case–Control Study on the Association of Porcine Circovirus Type 2 and Other Swine Viral Pathogens with Postweaning Multisystemic Wasting Syndrome
Authors: Pogranichniy Roman M. , Yoon Kyoung-Jin , Harms Perry A. , Sorden Steven D. , Daniels Michael
Published: May 2011

A field-based case–control study was conducted to assess the strength of association of porcine circovirus type 2 (PCV2) and some major swine viruses with postweaning multisystemic wasting syndrome (PMWS). Cases were defined as individual pigs with a clinical history of progressive weight loss and histopathological lesions characteristic of PMWS. Controls were pigs without clinical signs and histopathological lesions typical of PMWS. A total of 31 cases and 56 controls was identified from diagnostic submissions. Serum and various tissues were collected from all animals and assayed for PCV, porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus, porcine enterovirus types 1–3, swine influenza virus, porcine respiratory coronavirus, transmissible gastroenteritis virus, porcine endogenous retrovirus, porcine lymphotropic herpesvirus type 1, and bovine viral diarrhea virus. The proportion of case and control pigs positive for each virus was determined and statistically compared for determining the strength of the association that each virus had with PMWS individually or in combinations. Porcine circovirus type 2 had the strongest association (OR = 9.3, P = 0.006) with PMWS among the viruses tested for. Risk for PWMS was much higher (OR = 31.2, P = 0.0009) if the animal was concurrently infected with PCV2 and PRRSV, suggesting that development of PMWS may be enhanced by cofactor(s). Because PCV2 was also found in 62.5% of the controls, PCV2 from 5 cases and 4 controls were selected and genetically compared. No significant genetic difference was observed between PCV2 from PMWS and control pigs.
Use of a Mycoplasma Hyopneumoniae Nested Polymerase Chain Reaction Test to Determine the Optimal Sampling Sites in Swine
Authors: Kurth Kathy T. , Hsu Tsungda , Snook Eric R. , Thacker Eileen L. , Thacker Brad J. , Minion F. Chris
Published: May 2011

A number of polymerase chain reaction (PCR)-based diagnostic tests have been developed for Mycoplasma hyopneumoniae, including one from this research group. This report presents further development, optimization, and standardization of a nested PCR test. Detection sensitivity was 1 fg of M. hyopneumoniae chromosomal DNA (approximately 1 organism). This exceeded the sensitivity of or compared favorably with other published PCR tests. Polymerase chain reaction primers to porcine β2-microglobulin were included as internal controls for amplifiable chromosomal DNA from porcine samples. To standardize the test, a number of samples from experimentally infected pigs, including nasal, tonsil, tracheobronchial swabs, lung tissue, bronchial alveolar lavage (BAL) fluid, and tracheobronchial brush samples, were examined by PCR. Samples obtained from BAL fluid and tracheobronchial sites were most predictive of infection, whereas nasal swabs and lung tissue were not reliable indicators of experimentally induced infection. In conclusion, the nested PCR developed for this study was found to be a highly sensitive and specific diagnostic tool for M. hyopneumoniae, but the enhanced sensitivity may be unnecessary if the proper sites are sampled.
Managing Lead Exposure and Toxicity in Cow–Calf Herds to Minimize the Potential for Food Residues
Authors: Waldner Cheryl , Checkley Sylvia , Blakley Barry , Pollock Colleen , Mitchell Becky
Published: May 2011

Lead poisoning is commonly diagnosed in cattle. In this study, 3 groups of cattle from different herds accidentally exposed to discarded lead batteries on pasture were intensively studied to determine the extent and severity of exposure. The losses from acute death due to lead toxicity were substantial in all the 3 study groups at 12%, 17%, and 4%. Blood samples were taken from all cattle around the time of the first diagnosis and then later in 2 of the 3 herds to monitor the change in lead concentrations over time. Asymptomatic lead toxicosis was observed in these herds. In these 3 groups, between 4% and 12% of asymptomatic cattle had blood lead concentrations consistent with acute lead poisoning (>0.35 ppm), and between 7% and 40% of these asymptomatic animals were in the high-normal range (0.1–0.35 ppm). Because of the consistently high number of asymptomatic cattle with elevated lead levels, all cattle potentially exposed to a lead source should be tested before sale or slaughter to minimize the entry of lead into the food chain. The blood lead concentrations, which were monitored for months after the initial diagnosis, decreased slowly after the cattle were removed from the lead source. The prolonged retention of lead may be due to continued release and absorption of lead from metal particles in the reticulum or rumen. The mean reduction in the lead level was 0.046 ppm (95% CI, 0.017–0.075 ppm) every 30 days for these 2 herds. Using a single-component exponential model, the half-life of lead in the animals retested from Herds 1 and 2 was highly variable. The median half-life was 63 days (interquartile range, 34–107 days). One out of 8 pregnant heifers with high blood levels had a stillborn calf. There were no abortions or calf mortalities in this group. Blood samples were collected from the calves around the time of birth. The concentrations of lead in the blood of the calves exposed in utero were low (0.010–0.095 ppm).
Immunohistochemical Staining of Chlamydial Antigen in Emerald Tree Boas (Corallus Caninus)
Authors: Jacobson Elliott , Origgi Francesco , Heard Darryl , Detrisac Carol
Published: May 2011

Of 120 privately owned captive-bred and wild-collected emerald tree boas (ETBs) ( Corallus caninus), 97 died or were euthanatized. Eighteen snakes were necropsied, and tissues were collected from all major organs and processed for light microscopy. Histologic examination demonstrated histiocytic granulomas in the small intestine, heart, and esophageal tonsils of one ETB, small intestine of a second ETB, and in an esophageal tonsil of a third ETB. Within the center of these granulomas, small, basophilic, punctate organisms were demonstrated using hematoxylin and eosin staining. Transmission electron microscopic examination of an intestinal granuloma demonstrated developmental stages of organisms consistent with members of the family Chlamydiaceae. An immunoperoxidase staining technique and 2 different commercially available monoclonal antibodies against chlamydial lipopolysaccharide antigen was used to identify chlamydial antigen in these lesions. Liver of a puff adder ( Bitis arietans) with previously reported systemic chlamydiosis served as the positive control. Both monoclonal antibodies stained antigen in these granulomas. Additionally, macrophages within aggregates of lymphoplasmacytic cells in the colon, small intestine, and esophageal tonsils of 3 other ETBs contained antigen. Although both antibodies labeled antigen in serial sections of tissue, a difference in staining intensity was noted.
Retroperitoneal Extraskeletal Mesenchymal Chondrosarcoma in a Dog
Authors: Munday John S. , Prahl Annalisa
Published: May 2011

A young adult female Mastiff dog developed a large retroperitoneal mass, pleural effusion, and multiple pulmonary and pleural nodules. All masses were diagnosed as mesenchymal subtype chondrosarcomas, using histological and immunohistochemical criteria. Reports of canine extraskeletal mesenchymal chondrosarcomas (EMCs) are rare but involved animals less than 3 years of age in 60% of the cases. This is the first description of this type of tumor developing distant metastases. Evidence from this case and previous reports suggests that EMCs are associated with a poor prognosis.
Porcine Circovirus Type 2 (PCV-2) Coinfections in US Field Cases of Postweaning Multisystemic Wasting Syndrome (PMWS)
Authors: Pallarés F. J. , Halbur P. G. , Opriessnig T. , Sorden S. D. , Villar D. , Janke B. H. , Yaeger M. J. , Larson D. J. , Schwartz K. J. , Yoon K. J. , Hoffman L. J.
Published: May 2011

The prevalence of different pathogens detected in combination with porcine circovirus type 2 (PCV-2) was studied retrospectively in field cases of postweaning multisystemic wasting syndrome (PMWS) diagnosed at the Iowa State University Veterinary Diagnostic Laboratory, Ames, Iowa, between January 2000, and September 2001. The presence of PCV-2 antigen in lymphoid tissues and/or lung, demonstrated by immunohistochemistry, together with moderate to severe lymphoid depletion and/or granulomatous lymphadenitis, was used as the criteria for the diagnosis of PMWS. A total of 484 cases fulfilled these criteria. Most of the cases (294/369) of PMWS occurred in pigs between the ages of 8 and 18 weeks, with a peak at 10 weeks of age. Porcine reproductive and respiratory syndrome virus was detected in 51.9% of the cases, Mycoplasma hyopneumoniae in 35.5%, bacterial septicemia in 14.0%, bacterial pneumonia in 7.6%, swine influenza virus in 5.4%, and PCV-2 alone in 1.9%. In cases with bacterial septicemia the most frequently isolated pathogen was Streptoccocus suis. In cases with bacterial pneumonia, Pasteurella multocida was the most prevalent.
Application of the Neospora Caninum IgG Avidity ELISA in Assessment of Chronic Reproductive Losses after an Outbreak of Neosporosis in a Herd of Beef Cattle
Authors: Björkman Camilla , McAllister Milton M. , Frössling Jenny , Näslund Katarina , Leung Felicia , Uggla Arvid
Published: May 2011

Point-source infections are most likely the cause for Neospora caninum–induced abortion outbreaks in cattle, whereas an increased annual abortion rate may be a consequence of vertical transmission. The aims of the present study were to examine the reproductive effects of neosporosis in a beef herd for 3 years, after a point-source outbreak and to use IgG avidity serology to examine the chronicity of infections and patterns of transmission. During the study, 76–78% of animals were seropositive for N. caninum. The pregnancy rate varied from 88% to 94%, without any reduction in the pregnancy rate of seropositive cows compared with seronegative cows. The annual abortion rate was 2.5–5.5%, and all but 1 abortion occurred in seropositive dams. The efficiency of vertical transmission was estimated to be 85%. Several calves, born to seronegative dams, were seropositive at 6–13 months of age, indicating a 22% mean annual rate of horizontal transmission. The mean avidity in seropositive cows increased from 30 during the initial outbreak to 74 after 3 years. The mode of IgG avidity was 21–40 during the initial abortion outbreak, 41–60 after 1 year, and 61–80 after 2 and 3 years. The results reveal high annual rates of both vertical and horizontal transmission of N. caninum in a herd of beef cows and provide further validation on the ability of the N. caninum IgG avidity ELISA to accurately assess the chronicity of infection.
Comparison of a Serum Indirect Fluorescent Antibody Test with Two Western Blot Tests for the Diagnosis of Equine Protozoal Myeloencephalitis
Authors: Duarte Paulo C. , Daft Barbara M. , Conrad Patricia A. , Packham Andrea E. , Gardner Ian A.
Published: May 2011

A serum indirect fluorescent antibody test (IFAT) was compared with a Western blot (WB) and a modified Western blot (mWB) for diagnosis of equine protozoal myeloencephalitis (EPM). Using receiver-operating characteristic (ROC) analysis, the area under the curve of the IFAT was greater than the area under the curves of the WB and the mWB ( P = 0.025 and P = 0.044, respectively). There was no statistically significant difference between the areas under the curves of the WBs ( P > 0.05). On the basis of an arbitrarily chosen cut-off titer for a positive test result of 1:80 for the IFAT and interpreting weak positive WB results as positive test results, the sensitivities and 95% confidence intervals (CI) of all 3 tests were identical and equal to 88.9% (51.8–99.7%). The specificities and 95% CIs of the IFAT, WB, and mWB test were 100% (91–100%), 87.2% (72.6–95.7%), and 69.2% (52.4–83%), respectively. The overall accuracy of the IFAT was shown to be better than that of the WBs and, therefore, the test has potential for use in the diagnosis of EPM caused by Sarcocystis neurona.