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Summary

Epidural analgesia was achieved at weekly intervals in 6 adults llamas by injection of 2% lidocaine, 10% xylazine, and a combination of 2% lidocaine/10% xylazine at the sacrococcygeal junction. Analgesia was determined by lack of response to pin prick or hemostat pressure in the perineal area. Ataxia could not be accurately evaluated because of the llamas’ tendency to assume sternal recumbency when restrained. Time to onset of analgesia was not different between lidocaine (3.16 ± 0.31 minutes) and lidocaine/xylazine (3.50 ± 0.56 minutes), but results for both groups were different than those for xylazine (20.67 ± 3.37 minutes). Duration of analgesia was different among all groups (lidocaine, 71.0 ± 6.15 minutes; xylazine, 186.83 ± 14.86 minutes; lidocaine/xylazine, 325.83 ± 29.39 minutes). Mild sedation developed in 4 llamas given xylazine alone. Lidocaine/xylazine caused mild sedation in 2 llamas and moderate sedation in 1 llama. Significant changes in pulse or respiratory rates were not observed among drugs, but changes were observed over time with all drugs. As has been reported in other species, lidocaine/xylazine provided rapid onset and prolonged duration of analgesia.

Free access
in Journal of the American Veterinary Medical Association

Summary

An elisa was developed to detect antibodies to the 41-kd flagellin (P41) of Borrelia burgdorferi in serum obtained from cattle. Absorption studies, immunoblot analysis, immunoelectron microscopy, and correlation of results of the P41 -elisa and the P39- elisa as well as measurement of the antibody to P41 in calves challenge-exposed with Borrelia theileri were used to assess the specificity of the P41-elisa. Antigens derived from Escherichia coli, Leptospira interrogans serovar hardjo, and B burgdorferi were used for absorption studies and immunoblot analysis. Antibodies to P41 of B burgdorferi cross-reacted with antigens of E coli, but were not cross-reactive with L hardjo. A value 3 SD higher than the mean of the negative-control population of cattle was defined as the minimum value (cutoff value) for a positive result by the P41-elisa. Use of this value for classification of test results reduced the predicted rate of false-positive results attributable to E coli cross-reactivity to 1%. Immunoblot analysis revealed that test-positive serum from cattle reacted mainly with 41-, 39-, 34-, and 31-kd proteins of B burgdorferi, as well as several smaller proteins. Immunoelectron microscopy revealed that serum from cattle that was test-positive by the P41-elisa bound to the flagellin and outer membrane of B burgdorferi. Results of absorption studies, immunoblot analysis, and immunoelectron microscopy were correlated and indicated that serum from cattle that was test-positive by P41-elisa had stronger reactivity to B burgdorferi antigens than to antigens of E coli or L hardjo. The concentrations of antibodies measured by P41-elisa and P39-elisa testing were highly correlated (R2 = 0.78). Calves challenge-exposed with B theileri also had test-positive results by the P41-elisa as early as 2 weeks after exposure, but serum antibody concentrations decreased to prechallenge-exposure concentrations by 9 weeks after exposure. We concluded that the P41- elisa was useful as a screening method to detect B burgdorferi infections in cattle.

Free access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the prevalence of nonneoplastic middle ear disease among cats undergoing necropsy and the prevalence of clinical abnormalities in cats in which nonneoplastic middle ear disease was identified.

Design—Retrospective case series.

Animals—59 cats that underwent necropsy between January 1991 and August 2007.

Procedures—Medical records were searched to identify cats in which nonneoplastic middle ear disease was identified at necropsy. For cats included in the study, data that were recorded included signalment, initial complaint, whether the cat had any clinical signs of middle or external ear disease, whether the cat had upper respiratory tract disease, necropsy diagnosis, gross appearance of the bullae, and reason for euthanasia. Signs of middle ear disease that were considered included unilateral peripheral vestibular disease without motor deficits, Horner syndrome, and facial nerve paralysis.

Results—Of the 3,442 cats that underwent necropsy during the study period, 59 (1.7%) had nonneoplastic middle ear disease. Six of the 59 (10%) cats, including 1 cat that was affected bilaterally, had clinical signs of middle ear disease. Of these, 5 had signs of unilateral peripheral vestibular disease, and 1 had Horner syndrome.

Conclusions and Clinical Relevance—Results suggested that most cats with nonneoplastic middle ear disease did not have associated clinical signs. Findings may be of clinical relevance for cats in which middle ear disease is identified as an incidental finding during computed tomography or magnetic resonance imaging for unrelated diseases.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine relative sensitivities of the PK(15)- and WEHI 164(13)-based bioassays for detection of tumor necrosis factor α (TNF).

Sample Population

Recombinant human, murine, and porcine TNF, and serum from pigs given endotoxin IV.

Procedure

Two cell lines were used as targets for recombinant human, murine, and porcine TNF cytotoxicity bioassays. Pigs were given sublethal doses of endotoxin to obtain serum samples containing high activity of porcine TNF. Serum TNF activity was tested, using both cell lines. Viable cells were detected by addition of dimethylthiazol diphenyltetrazolium bromide after 18 to 20 hours’ incubation with samples containing TNF.

Results

The 2 cell lines tested had different sensitivities to human, murine, and porcine TNF. Compared with WEHI 164(13) cells, PK(15) cells were 50 times less sensitive to murine TNF and 15 times less sensitive to human TNF. However, PK(15) cells were 4 times more sensitive to recombinant porcine TNF and 15 times more sensitive to porcine serum containing TNF.

Conclusions

The PK(15) cell line was more sensitive to porcine TNF-mediated lysis than was the WEHI 164(13) cell line. The PK(15)-based TNF bioassay will be especially useful for study of infectious disease processes in swine, particularly where low activity of TNF exists. (Am J Vet Res 1997;58:1115–1119)

Free access
in American Journal of Veterinary Research

Abstract

Objective

To devise and test an IV methohexital infusion regimen for induction and maintenance of surgical anesthesia in dogs from which they would rapidly recover.

Design

Dose-response and plasma concentration-effect study.

Animals

11 clinically normal dogs.

Procedure

Bolus methohexital pharmacokinetic variables were determined in ketamine- and pentobarbital-anesthetized dogs. Plasma methohexital concentrations required to inhibit purposeful movement in response to painful stimuli were determined during a stepped methohexital infusion in the same dogs on a second occasion. These pharmacokinetic/pharmacodynamic data were next used to design a bolus and two-stage infusion regimen that would result in stable plasma methohexital concentrations with prolonged infusion. This regimen was tested in a second group of dogs.

Results

Mean steady-state volume of distribution of methohexital in the anesthetized dogs was 1.50 L/kg of body weight and mean elimination clearance was 10.2 ml/kg/min. Mean plasma concentrations required to prevent movement response to a noxious stimulus and at which the dogs could be extubated were 11.8 and 6.9 μg/ml, respectively. After a 6-hour infusion, recovery of airway reflexes sufficient to allow extubation required 67 minutes.

Conclusions

An easily implemented IV methohexital infusion regimen for induction and maintenance anesthesia in dogs was developed. During a 6-hour infusion, hemodynamic variables did not change. Use of this regimen resulted in anesthesia of sufficient depth to prevent withdrawal in response to noxious stimuli and in reliable and acceptable emergence times for use in canine survival studies in a cost-effective manner. (Am J Vet Res 1996;57:1044–1049)

Free access
in American Journal of Veterinary Research

Objective—

To evaluate chronic obstructive pulmonary disease of horses in Louisiana by assessing the signalment, history, environmental factors, clinical signs, and treatment of such horses.

Design—

Epidemiologic mail survey.

Sample Population—

83 of 240 veterinarians contacted by mail agreed to take part in the survey. Veterinarians contacted were listed as mixed-animal or equine practitioners in the 1991/1992 directory of the Louisiana Veterinary Medical Association or had submitted a specimen from a horse to the Louisiana Veterinary Medical Diagnostic Laboratory within the past 2 years.

Procedure—

The survey contained 47 questions designed to elicit information from owners and veterinarians about horses reported to have chronic obstructive pulmonary disease (COPD). Questions were included to evaluate age, breed, sex, vaccination history, respiratory disease history, environment of primary activity, level of exercise, primary residence (pasture or stall), condition of pasture or barn, type and condition of feed, clinical signs, concurrent conditions, and treatment regimen prescribed. Information from the returned forms was analyzed by using a microcomputer program designed for epidemiologic data.

Results—

Of the 83 veterinarians who agreed to participate, 31 returned 71 completed questionnaires for horses affected with COPD. Most affected horses were mature in age, kept on pasture, and had developed clinical signs during the summer months. The most consistent clinical signs were dry coughing, slight serous nasal discharge, labored expiratory effort, and flaring nostrils.

Clinical Implications—

Summer pasture-associated obstructive pulmonary disease appears to be precipitated by factors different than those associated with the traditionally diagnosed form of COPD and, thus, successful management measures may also vary. (J Am Vet Med Assoc 1996;208:248-251)

Free access
in Journal of the American Veterinary Medical Association

Summary

Experimental island and peninsular axial pattern flaps that incorporated the cranial superficial epigastric artery and vein were developed in 6 Beagles. Mean percentage of flap area that survived, for both flaps, was 87%, and percentage of surviving flap area was not significantly different for island versus peninsular flaps. In 1 dog, ligation of an aberrant, perforating branch of the cranial epigastric artery resulted in necrosis of 53% of the flap area. The cranial superficial epigastric axial pattern flaps have potential application for closure of skin defects within their arc of rotation and may be particularly useful for closure of large defects on the ventral aspect of the thorax. A peninsular flap was used to close a defect of the ventral portion of the thoracic wall in a clinical case.

Free access
in Journal of the American Veterinary Medical Association