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Comparison of polymerase chain reaction assays with bacteriologic culture, immunofluorescence, and nucleic acid hybridization for detection of Leptospira borgpetersenii serovar hardjo in urine of cattle
2000
Wagenaar, J. | Zuerner, R.L. | Alt, D. | Bolin, C.A.
Blood glycated hemoglobin evaluation in sick dogs
2000
Marca, M. C. | Loste, A. | Unzueta, A. | Perets, Mikhaʼel ben Yosef
Blood glycated hemoglobin concentration reflects long-term serum glucose levels in dogs. In this study, the effects of several diseases on blood glycated hemoglobin levels have been evaluated. For this study, blood samples were drawn from 93 unhealthy dogs. The animals were distributed into 10 groups according to pathological process (group 1, digestive problems; group 2, leishmaniasis; group 3, anemia; group 4, dermatological disorders; group 5, urinary problems; group 6, cardiorespiratory problems; group 7, diabetes mellitus; group 8, insulinoma; group 9, general diseases; group 10, control group). Blood glucose and glycated hemoglobin concentrations and hemoglobin and hematocrit values were analyzed in all the animals. In diabetic dogs, a strong increase in blood glycated hemoglobin was observed when compared with the other groups (P < 0.01). In contrast, dogs with insulinoma showed a decrease in blood glycated hemoglobin, though significant differences were not reported in all cases. No change in blood glycated hemoglobin concentrations were reported in dogs affected by other diseases. So, we can suppose that only the chronic alterations in glucose metabolism (chronic hyper- or hypoglycemia) can induce significant changes on the blood glycated hemoglobin concentrations in dogs.
اظهر المزيد [+] اقل [-]Agar gel immunodiffusion test for the detection of bovine leukemia virus antibodies: lack of trans-Atlantic standardization
2000
Simard, C. | Richardson, S. | Dixon, P. | Komal, J.
Two agar gel immunodiffusion (AGID) kits for the serodiagnosis of bovine leukemia virus (BLV) were imported from Europe and were compared with North American kits. The BLV AGID kits from North America and from Europe differed significantly. The punches were different, as were the pattern distribution in the agar of the reference and the test sera, resulting in differences in the reading of the immunoprecipitation lines. Based on the testing of 1200 serum samples from cattle, the European kits gave a good correlation with the American kits, as indicated by their respective kappa values. However, the European kits were found to be less sensitive when evaluated against weakly positive samples from field specimens or following a dilution trial. Only 65% and 50% of the weakly positive samples detected by the American kit #1 were detected by the European kits #2 and #3, respectively. The American kit was also capable of detecting BLV antibodies in 45% of strongly positive samples diluted 1/50 in negative sera, while antibodies were detected in only 15% of the samples with the European kit #2 and in none of the samples with the European kit #3. False negatives were also detected with the European kits. Among the false negatives, the degree of expected reactions was weak (European kit #2) or of varying degrees of positivity (European kit #3). Besides the differences in format and performance, the BLV-AGID kits in Europe are evaluated with the National Standard Serum E4 while a proficiency panel composed of a quadruplicate set of 10 reference sera is used in Canada to monitor the kits. Based on the overall observations, we noted a lack of standardization between the BLV-AGID kits used in North America and in Europe.
اظهر المزيد [+] اقل [-]Protection studies on winter dysentery caused by bovine coronavirus in cattle using antigens prepared from infected cell lysates
2000
Takamura, K. | Okada, N. | Ui, S. | Hirahara, T. | Shimizu, Y.
Cells infected with bovine coronavirus (BCV) were solubilized with Triton X-100 to yield a cell lysate (CL) antigen having high hemagglutinating (HA) titers. The antigen gave high HA titers using rat erythrocytes, suggesting that it contained large amounts of hemagglutinin esterase (HE) antigen. The CL antigen, combined with an oil adjuvant, was tested for protective and antibody-inducing activities in cattle. Four groups (2 cattle/group) of cattle were inoculated with CL antigen having HA titers of 16 000, 4000, 1000, and 250. Another group served as untreated controls. Two intramuscular inoculations were given at an interval of 3 wk. The animals were challenged with virus 1 wk after the second inoculation. The groups immunized with the CL antigen having an HA titer of 4000 or 16 000 produced hemagglutination inhibition (HI) antibody titers of > 320 and serum neutralizing (SN) antibody titers of > 1280. These groups of animals showed no clinical abnormalities after challenge. In the groups immunized with CL antigen at an HA titer of 1000 or 250, HI antibody titers were 40 to 160 and SN titers were 80 to 640. The cattle with HI antibody titers of > or = 160 and the SN titers of > or = 640 showed no clinical signs, but the cattle with the HI antibody titer < 80 and the SN antibody titer < 160 developed watery diarrhea and fever after challenge. These results indicate that CL antigen with high HA titer induces antibody production in cattle that provides effective protection against winter dysentery.
اظهر المزيد [+] اقل [-]Susceptibility of piglets to rabbit hemorrhagic disease virus following experimental infection
2000
Shien, J. H. | Lee, L. H.
The possibility exists that rabbit hemorrhagic disease virus (RHDV) can be transmitted to swine, through lapinized hog cholera virus (HCV) vaccine. To investigate the infectivity of RHDV in swine, 16 four- to six-week-old piglets were inoculated subcutaneously with RHDV, and samples of liver, lung, spleen, kidney, bile, adrenal gland, tonsil, mesenteric lymph node, thymus, urine, buffy coat, and feces were collected from each of 2 animals on Days 0, 1, 2, 3, 5, 7, 14, and 28 post infection. Using reverse transcription-polymerase chain reaction, viral RNA was detected in most tissues by Day 3 and was absent after Day 5, except in lung and liver tissues, in which viral RNA was detected up to Day 14. Viral RNA was not detected in kidney, urine, feces or bile. Antibody responses, as detected by hemagglutination inhibition, were of low titer and short duration, and were similar in animals inoculated with viable RHD and in those given formalin-inactivated RHDV (n = 2). Neither viral RNA nor antibody were detected in the negative control or in the uninfected, in-contact animals.
اظهر المزيد [+] اقل [-]Direct MS-MS identification of isoxsuprine-glucuronide in post-administration equine urine
2000
Bosken, J. M. | Lehner, A. F. | Hunsucker, A. | Harkins, J. D. | Woods, W. E. | Karpiesiuk, W. | Carter, W. G. | Boyles, J. | Fisher, M. | Tobin, T.
Isoxsuprine is routinely recovered from enzymatically-hydrolyzed, post-administration urine samples as parent isoxsuprine in equine forensic science. However, the specific identity of the material in horse urine from which isoxsuprine is recovered has never been established, although it has long been assumed to be a glucuronide conjugate (or conjugates) of isoxsuprine. Using ESI/MS/MS positive mode as an analytical tool, urine samples collected 4-8 h after isoxsuprine administration yielded a major peak at m/z 554 that was absent from control samples and resisted fragmentation to daughter ions. Titration of this material with increasing concentrations of sodium acetate yielded m/z peaks consistent with the presence of monosodium and disodium isoxsuprine-glucuronide complexes, suggesting that the starting material was a dipotassium-isoxsuprine-glucuronide complex. Electrospray ionization mass spectrometry negative mode disclosed the presence of a m/z 476 peak that declined following enzymatic hydrolysis and resulted in the concomitant appearance of peaks at m/z 300 and 175. The resulting peaks were consistent with the presence of isoxsuprine (m/z 300) and a glucuronic acid residue (m/z 175). Examination of the daughter ion spectrum of this putative isoxsuprine-glucuronide m/z 476 peak showed overlap of many peaks with those of similar spectra of authentic morphine-3- and morphine-6-glucuronides, suggesting they were derived from glucuronic acid conjugation. These data suggest that isoxsuprine occurs in post-administration urine samples as an isoxsuprine-glucuronide conjugate and also, under some circumstances, as an isoxsuprine-glucuronide-dipotassium complex.
اظهر المزيد [+] اقل [-]Comparative effects of the human protein C activator, Protac, on the activated partial thromboplastin clotting times of plasmas, with special reference to the dog
2000
Johnstone, I. B. | Martin, C. A.
The commercial snake venom extract, Protac, is a specific activator of the anticoagulant zymogen, protein C (PC) in human plasma. This specific action has led to its use in developing coagulation-based and amidolytic-based assays for the diagnosis of quantitative and/or qualitative PC deficiency states in human beings. The purpose of the present study was to compare the effects of Protac on the activated partial thromboplastin times (APTT) of human, bovine, equine, and canine plasmas in order to determine the potential value of this venom extract as an activator in functional PC assays in these domestic animal species. As expected, Protac significantly prolonged the APTT of normal human plasma, but had no effect on plasma known to be devoid of PC. Clotting times were prolonged by 34%-214% with concentrations of venom activator ranging from 0.1-1.0 U/mL. Under identical conditions, Protac prolonged the APTT of equine plasma by 11%-98% over control times. Even more dramatic was the inhibitory effect of Protac on the clotting of bovine plasma, extending the APTT more than 3-fold at a venom concentration of 0.1 U/mL. At higher venom concentrations, most bovine plasmas remained unclotted after 300 s (control time 34.1 s). Under similar conditions, the canine APTT was unaffected by Protac, even when the venom concentration was increased to 3 U/mL. In order to determine the reason for the lack in response of canine plasma, the concentration of the APTT reagent was altered (decreased), exposure time of the plasma to the Protac was increased from 2 min to 9 min, and the plasma was diluted to assess for the potential existence of plasma PC inhibitors. Protac caused an unexpected shortening of the APTT when the contact activator reagent was diluted. Increasing the exposure time had no effect. Although a slight prolongation of the canine APTT was detected when the plasma was diluted, the presence of strong plasma PC inhibition was considered an unlikely cause of the lack of significant anticoagulant action. The failure of Protac to exert a strong inhibitory effect on the canine APTT, as well as to generate amidolytic activity, suggests that this venom extract does not stimulate the production of activated PC activity in canine plasma. This may result from molecular differences in the canine PC molecule that prevent the formation of the stoichiometric complex of venom extract, APTT reagent, and canine protein, a complex thought to be essential for the PC-activating function of Protac. Protac may be suitable as an activator of PC in bovine and equine plasmas; however, it appears ineffective in generating anticoagulant activity in canine plasma.
اظهر المزيد [+] اقل [-]Type I interferon production in cattle infected with 2 strains of foot-and-mouth disease virus, as determined by in situ hybridization
2000
Brown, C. C. | Chinsangaram, J. | Grubman, M. J.
Four calves were exposed via aerosol to 1 of 2 strains of foot-and-mouth disease virus. Two animals received virus derived from an infectious clone virus (A12-IC) and 2 received virus derived from the same clone but which lacked the leader coding region (A12-LLV2) that codes for a protein responsible for turning off host protein synthesis. Animals were euthanized at 24 and 72 h post exposure. Cattle receiving A12-IC had a rapid course of disease with more virus in tissues while A12-LLV2-infected cattle did not develop clinical signs of disease. Formalin-fixed, paraffin-embedded tissue sections were probed with digoxigenin-labeled riboprobes corresponding to the coding sequence for bovine interferon (IFN) alpha and IFNbeta. Staining for IFNalpha mRNA was noted in mononuclear cells of the lungs of all animals and in respiratory lymph nodes of cattle receiving A12-IC. Staining for IFNbeta mRNA was confined to bronchiolar epithelium and present only in the animals infected with A12-IC. Inability of the A12-LLV2 virus to achieve levels of spread seen with A12-IC may be related to translation of IFNalpha in A12-LLV2-infected cells, which renders adjacent cells less susceptible to productive infection.
اظهر المزيد [+] اقل [-]Structure-related echoes in ultrasonographic images of equine superficial digital flexor tendons
2000
Schie, H.T.M. van | Bakker, E.M.
Ultrasonographic tissue characterization of equine superficial digital flexor tendons by means of gray level statistics
2000
Schie, H.T.M. van | Bakker, E.M. | Jonker, A.M. | Weeren, P.R. van