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931.
Objective-To determine whether clinical and clinicopathologic data could assist differentiation of congenital portosystemic shunts (CPSSs) from acquired portosystemic shunts (APSSs) in young dogs. Design-Retrospective case series. Animals-Dogs < 30 months of age with CPSSs (n = 62) or APSSs (31). Procedures-Medical records from 3 referral centers identified 31 dogs with APSSs and 62 dogs with CPSSs diagnosed from July 2003 to July 2008. Signalment, clinical signs, physical examination, and clinicopathological data were recorded, and statistical analyses were performed to determine differences between groups. Results-Univariable analysis showed APSS patients were older, heavier, and in poorer body condition, compared with CPSS patients. In CPSS patients, diarrhea was less prevalent, and neurologic signs were more prevalent. Ascites was more prevalent in APSS (Fisher exact test; OR, 50.2; 95% confidence interval [CI], 6.2 to 409.7), with no significant difference in albumin concentration between groups. The logistic regression model used to assess clinicopathological parameters showed lower Hct (OR, 1.42 × 10(-12); 95% CI, 1.42 × 10(-17) to 4.0 × 10(-6)), higher mean corpuscular volume (OR, 1.27; 95% CI, 1.08 to 1.50), and higher alanine aminotransferase concentrations (OR, 1.005; 95% CI, 1.001 to 1.009) were more likely in APSS patients. Conclusions and Clinical Relevance-Several clinicopathologic differences between dogs with congenital and acquired shunts were identified; however, assessed alone, these would be unlikely to enable differentiation between the 2 conditions. Awareness of the rarity of ascites in CPSS cases should prompt recognition of a likely diagnosis of APSS, allowing the veterinarian to target further diagnostics and counsel the owner appropriately.  相似文献   
932.
933.
This study evaluated a novel test strip designed to assess thiol levels as they relate to gingival/periodontal health in dogs. The simple to use strip (similar in form to a pH test strip) provides a colorimetric signal which estimates the level of thiols dissolved in oral fluid. Among several oral sites tested (left and right lingual vestibules, lower buccal vestibule, and upper buccal gingival margin), fluid from the maxillary gingival margin gave results with the best dynamic range, and its thiol levels correlated well with several oral health parameters (Pearson coefficients between 0.55 and 0.84; P < 0.001), especially those relating directly to the gingiva. The strip, which can be used on animals which are awake, may be useful as a quick, objective assessment of periodontal health, potentially enhancing compliance for thorough examinations, and promoting earlier and better-sustained treatment programs.  相似文献   
934.
It is of interest to evaluate crossbred pigs for hot carcass weight (HCW) and birth weight (BW); however, obtaining a HCW record is dependent on livability (LIV) and retained tag (RT). The purpose of this study is to analyze how HCW evaluations are affected when herd removal and missing identification are included in the model and examine if accounting for the reasons for missing traits improves the accuracy of predicting breeding values. Pedigree information was available for 1,965,077 purebred and crossbred animals. Records for 503,716 commercial three-way crossbred terminal animals from 2014 to 2019 were provided by Smithfield Premium Genetics. Two pedigree-based models were compared; model 1 (M1) was a threshold-linear model with all four traits (BW, HCW, RT, and LIV), and model 2 (M2) was a linear model including only BW and HCW. The fixed effects used in the model were contemporary group, sex, age at harvest (for HCW only), and dam parity. The random effects included direct additive genetic and random litter effects. Accuracy, dispersion, bias, and Pearson correlations were estimated using the linear regression method. The heritabilities were 0.11, 0.07, 0.02, and 0.04 for BW, HCW, RT, and LIV, respectively, with standard errors less than 0.01. No difference was observed in heritabilities or accuracies for BW and HCW between M1 and M2. Accuracies were 0.33, 0.37, 0.19, and 0.23 for BW, HCW, RT, and LIV, respectively. The genetic correlation between BW and RT was 0.34 ± 0.03, and between BW and LIV was 0.56 ± 0.03. Similarly, the genetic correlation between HCW and RT was 0.26 ± 0.04, and between HCW and LIV was 0.09 ± 0.05, respectively. The positive and moderate genetic correlations between BW and other traits imply a heavier BW resulted in a higher probability of surviving to harvest. Genetic correlations between HCW and other traits were lower due to the large quantity of missing records. Despite the heritable and correlated aspects of RT and LIV, results imply no major differences between M1 and M2; hence, it is unnecessary to include these traits in classical models for BW and HCW.  相似文献   
935.
Abstract: The objective of this study was to compare and investigate differences in glucose and lactate concentrations in sodium fluoride/potassium oxalate (NaF/Ox) plasma and serum in healthy cats and cats with metabolic disease. Glucose and lactate concentrations were determined in routinely processed serum and NaF/Ox plasma obtained from healthy (n = 30), hyperthyroid (n = 27) and diabetic (n = 30) cats, and in samples from 6 healthy cats stored at 25°C or 4°C for 0,1, 2, 4, or 8 hours. The packed cell volume (PCV) of blood collected in NaF/Ox was compared with that of blood collected in EDTA. Mean glucose concentration was significantly (P < .05) lower in NaF/Ox plasma than in serum in all groups of cats, by 0.7–2.5 mmol/L (11–45 mg/dL); the difference was greater in cats with hyperglycemia. Mean lactate concentration was significantly higher in serum than in NaF/Ox plasma in all groups of cats, by 0.4–1.2 mmol/L (3.6–10.8 mg/dL); the difference was greater in hyperthyroid and diabetic cats. In vitro, only serum stored on the clot for ≥ 1hour at 25°C had significantly lower glucose and higher lactate concentrations. The PCV of NaF/Ox-anticoagulated blood was lower than that of EDTA-anticoagulated blood, by 7.0%± 1.4% (P<.01). In conclusion, collection of feline blood in NaF/Ox was necessary to prevent in vitro increases in lactate concentration; however, NaF/Ox artifactually decreased plasma glucose concentration because of RBC shrinkage. The PCV should not be determined on blood collected in NaF/Ox.  相似文献   
936.
937.
OBJECTIVE: To determine clinical features of horses with bacterial meningitis or brain abscesses secondary to infectious disease processes involving the head. DESIGN: Retrospective study. ANIMALS: 7 adult horses. PROCEDURE: Medical records of Tufts University, the University of Pennsylvania, and the Livestock Disease Diagnostic Center (Lexington, Ky) were reviewed to identify adult (> 12 months old) horses in which a postmortem diagnosis of bacterial meningitis or brain abscess had been made. Horses were included in the study if an intracranial infection was confirmed, the horse had a primary infectious disease process involving the head, and there were no signs of systemic infection. RESULTS: 23 adult horses with bacterial meningitis or a brain abscess were examined during the study period, but only 7 met the criteria for inclusion in the study. Primary sites of infection included the paranasal sinuses, nasal cavity, periocular tissues, and submandibular lymph nodes. Three horses died suddenly prior to hospitalization, and 1 horse was hospitalized but died 7 days after the onset of neurologic abnormalities. The remaining 3 horses were euthanatized because of a rapid deterioration in clinical status. CONCLUSIONS AND CLINICAL RELEVANCE: Although rare, fatal intracranial complications can develop in horses with infectious diseases involving the head.  相似文献   
938.
In this study, we investigated the development of clinical disease and immune responses in the development of an experimental model of flea allergy dermatitis. Dogs were randomly divided into four treatment groups and were infested with fleas on two different feeding schedules (continuous and episodic). Group 1 consisted of four non-exposed dogs (negative controls) and Group 2 consisted of six dogs exposed to fleas continually. Groups 3 and 4 consisted of 14 dogs each that were exposed to fleas on an episodic schedule (two consecutive days every other week for 12 weeks). Group 4 also received intraperitoneal injections of a low dose of lectin (ricin) with immunomodulatory properties. The purpose of Group 4 was to investigate the effects of ricin on enhancing the development of clinical signs, flea antigen-specific IgE levels and altering the number of CD4+ and CD8+ T cell subsets in peripheral blood. Clinical signs developed in all flea exposed dogs, however, the dermatology lesion scores were less and shorter in duration for continuously exposed dogs compared to episodic exposed dogs, independent of ricin treatment. Lesion development was concentrated in the flea triangle and consisted principally of erythema, followed by alopecia, excoriation, papules, and crusts. CD4+ and CD8+ lymphocyte subsets or IgE levels were not altered by ricin treatment. Flea antigen-specific IgE values were highest in dogs exposed to fleas on a continuous basis compared to those episodically exposed. A greater percentage of clinical responder dogs with negative flea-specific IgE titers or negative intradermal test (IDT) were present in the episodic exposure groups than in the continuous exposure group. IgE titers corresponded slightly better with clinical responders than the IDT. The agreement between the IgE titers and IDT was good (weighted K = 0.67). Histopathology of skin samples were consistent with a Type I hypersensitivity. In conclusion, we were able to develop a model of flea allergy dermatitis by experimentally exposing dogs to fleas on an episodic and continuous feeding schedule. In this study, continuously exposed dogs did not develop immunotolerance, and ricin did not enhance the development of FAD.  相似文献   
939.
A 2-month-old Angus heifer was presented to Washington State University Veterinary Teaching Hospital for generalized peripheral lymphadenopathy and mild anorexia. Results of a CBC revealed marked lymphocytosis consisting primarily of large, atypical lymphocytes with cleaved, reniform nuclei. A presumptive diagnosis of sporadic juvenile lymphoma was made. To confirm these findings, a prescapular lymph node was submitted for histopathology, immunochemistry, and flow cytometric analysis. Peripheral blood also was analyzed by flow cytometry. Phenotypic characterization of lymph node and peripheral blood cell populations verified the calf had the B-cell form of sporadic juvenile lymphoma. The results of this investigation expand the phenotypic characterization of neoplastic lymphocytes in sporadic juvenile lymphoma.  相似文献   
940.
The purpose of this study was to determine the diagnostic utility of helical computed tomography (CT) for the diagnosis of ectopic ureters in the dog and to compare these findings with those of digital fluoroscopic excretory urography and digital fluoroscopic urethrography. Ureteral ectopia was confirmed or disproved based on findings from cystoscopy and exploratory surgery or postmortem examination. Of 24 dogs (20 female, 4 male) evaluated, 17 had ureteral ectopia. Digital fluoroscopic excretory urography and CT correctly identified ureteral ectopic status and site of ureteral ectopia (P < .05). Urethrography did not reliably detect ureteral ectopia. No false-positive diagnoses of ureteral ectopia were made in any of the imaging studies. Cystoscopic findings significantly agreed with findings during surgery in determining ureteral ectopic status and ectopic ureter site. One false-positive cystoscopic diagnosis of unilateral ureteral ectopia was made in a male dog. Kappa statistics showed better agreement between CT and both cystoscopy and surgical or postmortem examination findings with regard to presence and site of ureteral ectopia compared with other imaging techniques. CT was more useful than other established diagnostic imaging techniques for diagnosing canine ureteral ectopia.  相似文献   
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