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in Journal of the American Veterinary Medical Association

Objective

To assees the relationship of WBC counts and partial oxygen tension in the portal vein and caudal vena cava with portal bacteremia, bacteria in the liver, and postoperative morbidity and mortality in dogs with portosystemic shunts.

Design

Prospective study.

Animals

12 clinically normal dogs and 15 dogs with single congenital portosystemic shunts.

Procedure

Blood was collected from the portal vein and caudal vena cava for aerobic and anaerobic bacterial culture, WBC count, and measurement of partial oxygen tension. Samples of liver tissue, indwelling catheters, and fluids administered IV were also obtained for bacterial culture.

Results

Bacteria were cultured from samples obtained from the portal vein and caudal vena cava of 1 dog with a shunt and from the caudal vena cava of 1 clinically normal dog; neither dog had postoperative complications. In dogs with shunts and in clinically normal dogs, partial oxygen tension in the portal vein was significantly greater than that in the caudal vena cava. Postoperative complications were identified in 33% of dogs with shunts. Partial oxygen tensions of dogs with shunts with postoperative complications did not significantly differ from those of all dogs with shunts or dogs with shunts without complications. Significant differences in WBC counts were not found when comparing dogs with shunts with and without complications. Anaerobic bacteria were not cultured from the liver of any dog.

Clinical Implications

Leukocytosis, portal bacteremia, and portal hypoxemia were not notable findings in dogs with shunts and were not correlated with postoperative morbidity or mortality. (J Am Vet Med Assoc 1997;211:715–718)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine optimal zinc sulfate test solution concentration tor detecting failure ot passive transfer in calves.

Animals

235 calves (1 to 8 days old) from a calf-rearing operation in central Washington state.

Procedure

Zinc sulfate turbidity tests, using 200-, 250-, 300-, 350-, and 400-mg/L test solutions, were performed on calf serum. These increasing concentrations were evaluated for detection of failure of passive transfer Using 1,000 mg of IgG,/dl as the threshold for adequate passive transfer, sensitivity, specificity, and accuracy of classification were determined by comparing the zinc sulfate test results with serum IgG, concentration (mg/dl) measured by radial immunodiffusion.

Results

The 200-mg/L zinc sulfate turbidity test solution was 100% sensitive; however, specificity was only 25 5% Increasing concentrations of zinc sulfate test solution up to 350 mg/L improved specificity with either no change or small decreases in sensitivity.

Conclusion and Clinical Relevance

The endpoint of the traditional 208-mg/L zinc sulfate turbidity test for failure of passive transfer in calves is too high. Increased test solution concentrations improve specificity with only minor adverse effects on sensitivity. (Am J Vet Res 1996;57:1711–1713)

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in American Journal of Veterinary Research

Abstract

Objective

To investigate whether the procedure used to snare and restrain pigs during collection of blood samples would alter in vitro functional capacity of leukocytes in the samples.

Animals

8 gilts.

Procedure

Catheters were surgically inserted into the jugular vein of gilts to enable blood sample collection without restraint. After collection of a control sample, gilts were restrained by use of a snare and samples were collected at 0.5, 3.5, and 6.5 minutes after start of restraint (0 minutes). At each time point, plasma β-endorphin and cortisol concentrations as well as WBC counts were recorded, and functional capacity of leukocytes in cultures of whole blood was assessed by means of mitogen-induced proliferation and interleukin-2 activity, virus-induced interferon-α concentration, and phagocytosis of zymosan particles.

Results

Concentrations of plasma β-endorphin and cortisol were increased at 3.5 and 6.5 minutes after start of restraint. At these times, virus-induced interferon-α concentration was decreased, whereas proliferative response to Concanavalin A and phytohemagglutinin increased in samples collected at 6.5 minutes.

Conclusion and Clinical Relevance

It was possible to snare pigs for the purpose of collecting blood samples and restrain them without causing excessive stress that would affect immunologic variables, provided that the collection procedure was completed within a few minutes. (Am J Vet Res 1998;59:421–425)

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in American Journal of Veterinary Research

Summary

Fifteen isolates of Escherichia coli obtained from the blood and tissues of septic foals had plasmid dna of size ranging from 2.5 to 93 megadaltons. These isolates grew in normal equine serum (serum resistant), a trait previously documented to be expressed by isolates obtained from blood and tissues of septic foals, but not by isolates obtained from the feces of clinically normal horses. Of these isolates, 3 contained conjugal plasmids that encoded resistance to multiple antimicrobial agents linked to serum resistance and, in 1 isolate, to production of aerobactin as well. Serum resistance and production of aerobactin are related to virulence of septicemic E coli from non-equine sources.

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in American Journal of Veterinary Research

Summary

The efficacy of a 1-step surgical preparation technique for skin of dogs prior to elective ovariohysterectomy was evaluated. Dogs randomly assigned to group 1 (n = 30) had their skin prepared for surgery by use of a 2-step method, whereas the skin of dogs in group 2 (n = 30) was prepared for surgery by use of a commercially available product for a 1-step technique. Culture plates for quantitative bacterial counts were applied to the proposed incision site on dogs under general anesthesia after hair at the site was clipped and vacuumed but before antiseptic was applied. A second quantitative bacterial culture plate was applied to the proposed incision site after completion of the surgical preparation technique. Surgeries were routinely completed, and dogs were evaluated by physical examination the next day and at the time of suture removal (7 to 10 days after surgery) for complications. Postoperative complications were minor and consisted primarily of subcutaneous swelling, which resolved with time. All cultures obtained prior to skin preparation included bacteria or yeast. Sixteen cultures obtained after skin preparation (group 1, n = 11; group 2, n = 5) included bacteria or yeast. The total number of colonies of potential pathogens (Staphylococcus sp and Enterobacteriaceae) on the prepreparation cultures was 9,339; 4 colonies were counted on the postpreparation cultures. Potential bacterial pathogens, ie Streptococcus intermedius and gram-negative bacteria, were isolated from dogs prepared with the 2-step technique. None of the dogs that developed postoperative complications had growth on postpreparation culture plates.

There was no significant difference in the percent reduction of microbial numbers after skin preparation for either group. There was a significant (P < 0.05) difference between the pre- and postpreparation microbial numbers for both preparation techniques.

The 1-step technique was a simple, effective, and efficient method of skin preparation in dogs undergoing elective ovariohysterectomy.

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in Journal of the American Veterinary Medical Association

SUMMARY

A total of 22 clinical streptococcal isolates, pre-dominantly Streptococcus zooepidemicus, associated with endometritis in horses were tested for their ability to withstand the natural bactericidal properties of freshly obtained blood. During a 3-hour incubation in blood from a single horse, 8 of these isolates survived and grew; the remainder were killed. To determine whether this ability to grow extended to blood of other horses, 5 of these growing isolates were tested for their ability to grow in the blood of 5 additional horses. The same 5 horses were used for each isolate. The isolates grew in blood of some of the horses, but were killed in blood of the others. However, the horse’s blood that mediated killing was different for each isolate. Killing required leukocytes, but the specificity for killing appeared to reside in plasma, although plasma by itself was not bactericidal. Heatstable and heat-labile components in plasma, interpreted as antibody and complement, respectively, appeared necessary for killing. Isolates that could grow in fresh blood lost this ability after 10 passages in artificial media. Results of these experiments of phagocytosis in fresh blood may provide helpful insights into the phagocytosis of S zooepidemicus in equine uterine fluid.

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

Summary

Purebred Beagles were inoculated with Trypanosoma cruzi isolates from a North American opossum or armadillo (Tc-W), and dog (Tc-D). Although Tc-D established infection in dogs, the dogs did not develop cardiac abnormalities. Dogs inoculated with Tc-W developed acute myocarditis associated with increases in P-R interval, atrioventricular block, depression of R wave amplitude and shifts in mean electrical axis. Echocardiograms were normal during this stage. Three Tc-W-inoculated dogs died during the acute stage. Following the acute stage, 5 of 8 Tc-W-inoculated dogs entered an indeterminate stage in which ecg changes were minor and echocardiograms were normal. Progression to the chronic stage in 5 of the 8 Tc-W-inoculated dogs was indicated by development of ventricular-based arrhythmias, mainly ventricular premature contractions, between postinoculation days 60 and 170. In some dogs, ventricular premature contractions were multifocal. Electrocardiographic abnormalities progressively degenerated to various forms of ventricular tachycardia. Worsening ecg coincided with loss of left ventricular function as measured by echocardiography. Mean percent ejection fraction and percentage of fractional shortening decreased to 63% and 52% of control values, respectively. The left ventricular free wall (lvfw) thickness decreased and % septal: % lvfw thickening ratio increased, indicating a relative preservation of septal wall motion and lvfw hypokinesis.

Free access
in American Journal of Veterinary Research
Authors and

Summary

The hexon subunit of bovine adenovirus serotype 3 (bav-3) was purified by use of anion-exchange chromatography. A vaccine composed of the purified hexon in immune-stimulating complexes was administered and induced high titer of virus-neutralizing antibody in rabbits and calves.

Free access
in American Journal of Veterinary Research