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Результаты 101-110 из 462
Effects of anesthesia induced and maintained by continuous intravenous administration of guaifenesin, ketamine, and xylazine in spontaneously breathing sheep
1993
Lin, H.C. | Tyler, J.W. | Welles, E.G. | Spano, J.S. | Thurmon, J.C. | Wolfe, D.F.
Anesthesia was induced and maintained in 6 Suffolk wethers by continuous IV infusion of guaifenesin (50 mg/ml), ketamine (1 mg/ml), and xylazine (0.1 mg/ml) in 5% dextrose in water (triple drip) to assess the anesthetic and cardiopulmonary effects. All sheep were positioned in right lateral recumbency. Dosages of triple drip used for induction and maintenance of anesthesia were 1.2 +/- 0.02 ml/kg and 2.6 ml/kg/h, respectively. Lack of gross purposeful movement of sheep to electrical stimulation indicated that analgesia and muscular relaxation induced by triple trip were adequate for surgical procedures. Heart rates and arterial blood pressure remained unchanged from baseline values during a 1-hour period of anesthesia. Arterial blood pressures were measured indirectly, using an inflation cuff placed over the metatarsal artery at the heart level. Significant decrease in arterial partial pressure of O2 (PaO2), coupled with an increase in arterial partial pressure of CO2 (PaCO2), from baseline values was observed throughout the course of the study. Decrease in PaO2 was observed concomitantly with significant (P < 0.05) increase in respiration rate. Changes in arterial blood gas tensions observed in this study were attributed to respiratory depressant effect induced by anesthetic drugs and right-to-left shunting, perfusion/ventilation mismatch, or both caused by right lateral recumbency. Administration of 100% O2 via the endotracheal tube reduced the magnitude of the decrease in PaO2. All sheep recovered smoothly and stood within 96.3 +/- 48.9 minutes after termination of triple drip administration.
Показать больше [+] Меньше [-]Transmission of proliferative enteritis to swine by use of embryonating chicken eggs
1993
Jones, G.F. | Ward, G.E. | Collins, J.E. | Gebhart, C.J.
Embryonating eggs were inoculated with filtered porcine ileal mucosa containing intracellular curved rods (ICR) and incubated for 4 to 6 days. Three of 12 pigs given the eggs per os developed microscopic lesions of proliferative enteritis (PE). Nonchallenge-exposed control pigs did not develop lesions of PE. Four of six positive control pigs given ileal mucosa from pigs with PE also developed microscopic lesions of PE. All of the PE lesions were found in pigs necropsied 10 to 29 days after challenge exposure. None of the swine in the study had clinical signs or gross lesions of PE. Campylobacter spp were isolated from pigs with and without exposure to the ileal mucosa from pigs with PE. There was no relationship between Campylobacter spp isolation and development of lesions. Deoxyribonucleic acids extracted from embryonating chicken eggs injected with the equivalent of 0.5 mg of mucosal lesions and incubated for 4 days hybridized to a DNA probe specific for the ICR whereas DNA extracted from 1.5 mg of mucosal homogenates of the same proliferative tissue did not hybridize with the same probe. Results of these experiments indicated that ICR injected into eggs remained infective for pigs and suggest replication of ICR in the first-passage eggs.
Показать больше [+] Меньше [-]Antigen-capture enzyme immunoassay for detection of avian influenza virus in turkeys
1993
Kodihalli, S. | Sivanandan, V. | Nagaraja, K.V. | Goyal, S.M. | Halvorson, D.A.
A double-antibody sandwich ELISA (DAS-ELISA) was developed for detection of avian influenza virus (AIV) antigen. A monoclonal antibody to the viral nucleoprotein (NP) was used to coat the ELISA plates. A direct DAS-ELISA and an indirect DAS-ELISA were evaluated. In the direct DAS-ELISA, monoclonal antibody to the AIV NP conjugated with horseradish peroxidase was used. The direct DAS-ELISA was evaluated for its sensitivity to detect purified NP; this procedure detected as little as 0.1 ng. In the indirect DAS-ELISA, rabbit NP antibody and horseradish peroxidase-conjugated goat anti-rabbit immunoglobin were used as primary and secondary antibodies, respectively. The indirect DAS-ELISA was evaluated for its ability to detect the AIV antigen in tracheal and cloacal specimens from turkeys inoculated with AIV. Results of indirect DAS-ELISA were compared with those of conventional virus isolation. Percentage agreement between indirect DAS-ELISA and virus isolation in AIV-positive samples was found to be 76.1% and, in AIV-negative samples, it was found to be 82.1%. These results indicate that the DAS-ELISA might be a viable alternative to virus isolation because of its rapidity, compared with virus isolation.
Показать больше [+] Меньше [-]Toxin production by Pasteurella multocida isolated from rabbits with atrophic rhinitis
1993
DiGiacomo, R.F. | Deeb, B.J. | Brodie, S.J. | Zimmerman, T.E. | Veltkamp, E.R. | Chrisp, C.E.
Naturally acquired turbinate atrophy in rabbits was associated with Pasteurella multocida infection. Several in vitro and in vivo studies were conducted to document toxin production from P. multocida isolates and to determine the relation of toxin to atrophic rhinitis in rabbits. Ten isolates of P. multocida serotype A:12 were obtained from adult New Zealand White rabbits with noninduced atrophic rhinitis. Specific-pathogen-free rabbits inoculated intranasally with isolates of P. multocida developed rhinitis and turbinate atrophy. However, inoculation with filtrates of the same bacteria failed to induce turbinate atrophy. Cytotoxicity was observed in assays, using bovine embryonic turbinate cell cultures with extracts of P. multocida, but not in agar overlay cytotoxicity assays, using bovine embryonic turbinate, bovine embryonic lung, or Vero cell cultures, or in a sandwich ELISA, using monoclonal antibodies to purified P. multocida toxin. Thus, turbinate atrophy was experimentally reproduced in rabbits with isolates of P. multocida, but toxin was only detected in vitro by cell culture assay of P. multocida extracts.
Показать больше [+] Меньше [-]Comparison of a visual analogue scale and a numerical rating scale for assessment of lameness, using sheep as a model
1993
Welsh, E.M. | Gettinby, G. | Nolan, A.M.
A study was designed to compare use of an numerical rating scale (NRS) and a visual analogue scale (VAS) for subjective assessment of lameness, using sheep as a model. The NRS consisted of 5 divisions, 0, 1, 2, 3, and 4; 4 of these divisions (1-4) described lameness. The VAS used a 100-mm horizontal line with vertical bars at either end; one end was labeled 'sound' and the other was labeled 'could not be more lame.' Two independent observers graded lameness in 62 sheep, and between- and within-observer differences were assessed for each scoring system to compare the NRS with the VAS. Results indicated no significant differences between the 2 observers scoring lameness, using either the VAS or the NRS. The scores obtained, using the VAS, were not normally distributed, although differences between scores for the 2 observers were. The NRS scores followed a normal distribution pattern. Investigation of repeated measurement for the same sheep, using both scales, revealed no significant difference between either. A comparison of the NRS and VAS scores made by each observer indicated that although correlation was good (observer 1; r = 0.94; observer 2; r = 0.95), there was not perfect agreement. The maximal NRS score of 4 was associated with VAS values > 68 mm, indicating that the NRS divisions did not reflect equal increases in lameness. The VAS and NRS scores for each observer were highly reproducible, although they were more variable for sheep that were regarded as moderately lame. Results indicate that although the NRS and VAS compared favorably with respect to repeatability, reproducibility, and use by 2 observers, the VAS is inherently more sensitive. In addition, the NRS and VAS should not be use interchangeably.
Показать больше [+] Меньше [-]Prevalence of mycoplasmal and ureaplasmal recovery from traceobronchial lavages and of mycoplasmal recovery from pharyngeal swab specimens in cats with or without pulmonary disease
1993
Randolph, J.F. | Moise, N.S. | Scarlett, J.M. | Shin, S.J. | Blue, J.T. | Corbett, J.R.
The prevalence of mycoplasmal and ureaplasmal recovery from tracheobronchial lavage specimens and prevalence of mycoplasmal recovery from pharyngeal swab specimens from cats with (28) or without (18) pulmonary disease were determined. Mycoplasmas were recovered from tracheobronchial lavage specimens in 21% of cats with pulmonary disease, but in no cats without pulmonary disease; this difference is significant (P = 0.04). Mycoplasmal recovery from tracheobronchial lavage specimens was not significantly associated with concurrent Pasteurella spp isolation, septic inflammation, or bronchitis. Ureaplasmas were only isolated from a tracheobronchial lavage specimen in cat with pulmonary disease and in no cats without pulmonary disease. Similar mycoplasmal recovery rates were found for pharyngeal swab specimens from cats with (39%) or without (35%) pulmonary disease. Seemingly, mycoplasmas are part of the normal pharyngeal flora in approximately a third of the feline population, but mycoplasmas are not normal inhabitants of the lower respiratory tract in cats. It is unknown whether mycoplasmas isolated from tracheobronchial lavage specimens in cats with pulmonary disease are primary pathogens or opportunistic invaders. Seemingly, ureaplasmas are seldom associated with pulmonary disease in cats, and are not normal inhabitants of the trachea and bronchi of cats.
Показать больше [+] Меньше [-]Capacitation-like membrane changes and prolonged viability in vitro of equine spermatozoa cultured with uterine tube epithelial cells
1993
Ellington, J.E. | Ball, B.A. | Blue, B.J. | Wilker, C.E.
Reliable capacitation of equine spermatozoa has been a major obstacle in the development of equine in vitro fertilization. Experiments were done to compare in vitro capacitation of equine spermatozoa by use of heparin/caffeine, calcium ionophore, uterine tube epithelial cell (UTEC)-conditioned medium, and direct culturing of spermatozoa with UTEC (coculturing). Capacitation-like changes, as determined by chlortetracycline membrane staining patterns, developed with UTEC-conditioned medium and coculturing, equivalent to that with calcium ionophore. Both of these treatments induced more (P < 0.05) capacitation-like changes than did the control, a modified Tyrode's medium. More (P < 0.05) spermatozoa were viable after 24 hours of UTEC coculturing than in the control incubation.
Показать больше [+] Меньше [-]Lack of residual lung damage in horses in which Rhodococcus equi-induced pneumonia had been diagnosed
1993
Ainsworth, D.M. | Beck, K.A. | Boatwright, C.E. | Snedden, K.A. | Rebbun, W.C.
The effect of prior Rhodococcus equi-induced pneumonia on pulmonary health was investigated in 5 horses (< 24 months old) using endoscopy, radiography, hematologic and bronchoalveolar lavage analyses, and pulmonary function testing. Rhodococcus equi-induced pneumonia had been diagnosed in principal horses when they were foals. Diagnosis was based on positive results of transtracheal aspiration and thoracic radiography at the time of initial clinical examination. Results of reevaluation of the respiratory system of these horses (R+) were compared with those of 5 age-matched healthy horses (R-) that lacked clinical or historical evidence of foalhood pneumonia. Significant differences in variables between the 2 groups of horses were not evident. In both groups, most horses had radiographic evidence of an accentuated bronchointerstitial pattern, although results of analysis of bronchoalveolar lavage specimens were normal and mononuclear cells predominated. Variability in results of the pulmonary function tests was observed within and between the 2 groups of horses. Only normatized dynamic lung compliance was slightly lower in the previously infected horses, but this difference was not significant. We concluded that horses previously infected with and successfully treated for R equi-induced pneumonia do not have detectable evidence of residual lung damage.
Показать больше [+] Меньше [-]Humoral immune responses in cats with dermatophytosis
1993
Sparkes, A.H. | Stokes, C.R. | Gruffydd-Jones, T.J.
The IgG and IgM classes of antibodies to a water-soluble antigen preparation derived from microsporum canis were determined by ELISA in the sera of 79 cats with dermatophytosis confirmed by results of fungal culture, and of 46 specific-pathogen-free-derived, barrier-maintained cats with no previous exposure to dermatophytes. Of the 79 cats with dermatophytosis, the species isolated were: M canis from 72, M gypseum from 6, and Trichophyton mentagrophytes from 1. Concentrations of soluble M canis antigen-specific IgG and IgM were significantly (P < 0.05) higher in the cats with dermatophytosis than in the control cats. The IgG concentration was larger than or equal to 2.0 ELISA units/ ml in 71% of the cats with dermatophytosis and in 9% of the control cats, whereas IgM concentration was greater than or equal to 4.0 ELISA units/ml in 38% of the cats with dermatophytosis and in 11% of control cats. There was no significant difference in either IgG or IgM values between the cats with M canis infection and those with other non-M canis dermatophyte infections.
Показать больше [+] Меньше [-]Production and characterization of VP4/VP7 reassortant swine rotaviruses derived from Gottfried and OSU parental strains
1993
Hesse, R.A. | Couture, L.P. | Ellsworth, S.R. | Duhamel, G.E. | Lu, W. | Dickinson, E.O. | Benfield, D.A.
The ability of viral glycoproteins (VP) VP4/VP7 reassortant swine rotaviruses (RV) to induce cross-neutralizing antibody against parental serotypes was investigated in guinea pigs. Using selective culture conditions, we produced 10 reassortant viruses that contained gene segment 4 of the OSU RV strain and gene segment 9 of the Gottfried RV strain. These reassortant RV grew to high titer in cell culture and were neutralized by monospecific antisera against both parental RV strains. The reassortant RV were chemically inactivated with binary ethylenimine, adjuvanted with aluminum hydroxide, and used to produce antisera in guinea pigs. The hyperimmune antisera had high neutralization titer against both parent RV strains. These results indicate that several of the reassortant RV may be capable of inducing neutralizing antibodies to VP4 and VP7 and may have future use as bivalent vaccine strains.
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