Comparison of biopsy samples obtained using standard endoscopic instruments and the harmonic scalpel during laparoscopic and laparoscopic-assisted surgery in normal dogs

Objectives— To compare tissue specimens of canine abdominal organs collected by standard techniques (ST) and harmonic scalpel (HS) and to determine the effect of each technique on wound healing.
Study Design— Experimental.
Animals— Twelve dogs.
Methods— Paired biopsy samples (ST, HS) were collected from liver, spleen, adrenal gland, pancreas, stomach, jejunum, and bladder using laparoscopic or laparoscopic-assisted methods. Hemorrhage at biopsy sites was assessed (present or absent). Specimens were evaluated for diagnostic quality and histologic changes. Dogs were necropsied at 4 or 14 days postoperatively.
Results— HS incision caused less frequent hemorrhage of all organs except spleen. HS specimens had more coagulation necrosis than ST specimens, but both techniques yielded specimens that were sized similarly and were of diagnostic quality. At necropsy, HS biopsy sites of the stomach, jejunum, bladder, adrenal gland, and pancreas were more hyperemic than ST sites. There were more adhesions at jejunal and pancreatic ST biopsy sites. HS biopsy sites had more coagulation necrosis at days 4 and 14 postoperatively. Differences in fibrin deposition, inflammation, and fibrosis were present at biopsy sites of some organs at days 4 or 14 and in comparisons between days 4 and 14.
Conclusions— Diagnostic quality biopsy specimens were obtained with HS and ST. Although HS-induced gross and histologic changes during the first 2 postoperative weeks, no clinical complications were observed.
Clinical Relevance— Both HS and ST can yield specimens with minimal hemorrhage and HS resulted in no apparent postoperative problems in normal dogs. Although HS caused more inflammation and adhesions at biopsy sites of the pancreas, adrenal gland, and jejunum, no clinical complications occurred.     

Optimization of conditions for in vitro production of radical oxygen species and expression of tissue factor by canine mononuclear cells and granulocytes for use in high-throughput assays

The purpose of this study was to optimize conditions for high throughput measurement of radical oxygen species (ROS) production and expression of tissue factor, also termed procoagulant activity, by canine leukocytes. Granulocytes and mononuclear cells were separated by density gradient centrifugation from peripheral blood collected on several occasions from three healthy large breed dogs. To determine optimal conditions for ROS production, granulocytes were incubated for 1 or 3h in PBG (PBS containing 0.5% BSA and 5mM glucose) or RPMI containing 10% fetal bovine serum (FBS); lipopolysaccharide (LPS), zymosan, peptidoglycan (PGN) and phorbol myristate acetate (PMA) were used as stimuli. ROS was assessed by conversion of the nonfluorescent dye dihydrorhodamine 123 to fluorescent rhodamine 123 by radical species released into the media. To identify optimal conditions for expression of tissue factor, mononuclear cells were incubated for 5h in RPMI containing different concentrations of heat-inactivated FBS (HI-FBS), and LPS, zymosan, PGN or PMA as stimuli. Expression of tissue factor was determined using a one-stage recalcification assay performed in an automated nephelometric coagulation analyzer. Neither LPS nor zymosan increased ROS production by granulocytes incubated in PBG media. In contrast, granulocytes incubated in RPMI had dose-dependent increases in ROS production in response to zymosan and PGN. ROS production was significantly increased by incubation with concentrations of LPS of 0.01microg/ml or greater, and by zymosan concentrations of 0.1microg/ml or greater. ROS production in response to incubation with PMA was significantly increased starting at 10(-7)M, and was significantly greater for cells incubated in RPMI than cells incubated in PBG. LPS-, zymosan- and PGN-stimulated procoagulant activity increased in a dose-dependent manner, whereas PMA-stimulated procoagulant activity peaked at 10(-7)M. Increasing concentrations of HI-FBS significantly increased LPS-, zymosan- and PGN-induced procoagulant activity of mononuclear cells. Results obtained in this study indicate production of ROS by canine granulocytes is optimal when these cells are incubated for 3h in RPMI with LPS (0.1microg/ml), zymosan (10 microg/ml), PGN (10 microg/ml), and PMA (10(-7)M). Furthermore, canine mononuclear cells express procoagulant activity in response to LPS, zymosan, PGN, and PMA, and responses to LPS, zymosan and PGN are enhanced by the addition of HI-FBS. These findings suggest that HI-FBS retains important serum proteins that facilitate interactions between each of these bacterial or yeast derived products and the mononuclear cells. Consequently, future studies regarding the regulation of procoagulant activity by canine mononuclear cells should be performed in the presence of HI-FBS. Both assays utilized in this study allow high throughput of samples, and therefore are appropriate choices for rapid screening of conditions and/or therapeutic interventions affecting the canine inflammatory system.     

Development of a two-step nested duplex PCR assay for the rapid detection of Brachyspira pilosicoli and Brachyspira intermedia in chicken faeces

Avian intestinal spirochaetosis (AIS) is an infection of the caeca and/or colo-rectum of laying and meat breeder hens caused by anaerobic intestinal spirochaetes of the genus Brachyspira. AIS can result in a variety of symptoms, including delayed and/or reduced egg production, and increased faecal water content. The two most commonly reported Brachyspira species involved in AIS are Brachyspira pilosicoli and Brachyspira intermedia, and their detection and identification can be difficult and time consuming. In the current study a two-step nested duplex PCR (2S-N-D-PCR) was developed for the detection of these two species, using DNA extracted from washed chicken faeces. In the first step, a duplex PCR (D-PCR) amplifying Brachyspira genus-specific portions of the 16S rRNA and NADH oxidase (nox) genes was undertaken on the washed faeces. In the second step, a nested D-PCR was used that amplified species-specific portions of the 16S rRNA gene of B. pilosicoli and the nox gene of B. intermedia from the amplicons produced in the first step. The 2S-N-D-PCR was rapid and specific, and could be used to detect approximately 10(3) cells of each spirochaete species per gram of washed faeces. When tested on 882 chicken faecal samples from infected flocks, it detected 4-5% more positive faecal samples than did the standard method of selective anaerobic culture followed by individual species-specific PCR assays conducted on the growth on the primary plate. The application of this new technique should improve diagnostic capacity, and facilitate further studies on AIS.     

Effects of intravenous diazepam or microdose medetomidine on propofol-induced sedation in dogs

This crossover study tested the hypothesis that both diazepam and microdose medetomidine would comparably reduce the amount of propofol required to induce sedation. Four different medications, namely high-dose diazepam (0.4 mg/kg intravenously [IV]), low-dose diazepam (0.2 mg/kg IV), medetomidine (1 mug/kg IV), and placebo (0.5 mL physiological saline IV) were followed by propofol (8 mg/kg IV) titrated to a point where intubation could be performed. The effects of medetomidine were comparable to the effects of high-dose diazepam and significantly better than the effects of low-dose diazepam or placebo. Dogs in all treatment groups had transient hypoxemia, and induction and recovery qualities were similar.     

The clinical usefulness of the ventrodorsal versus dorsoventral thoracic radiograph in dogs

Differences exist in the ventrodorsal (VD) and dorsoventral (DV) radiographic views of the canine thorax. One view may be preferred over another because of how it portrays different areas of interest or different disease conditions. The VD view is indicated for evaluation of the cranial and caudal mediastinum, the caudal vena cava, and the accessory lung lobe, and in cases of pleural effusion. Indications for the DV view include assessment of a consistent cardiac silhouette, evaluation of the pulmonary lobar vessels, and evaluation of the structures of the dorsal thorax, such as hilar lymph nodes, the caudal dorsal lungs, trachea, mainstem bronchi, and left atrium.     

Academic food-supply veterinarians: future demand and likely shortages

The future demand for and potential shortages of food-supply veterinarians have been the subject of much concern. Using the Delphi forecasting method in a three-phase Web-based survey process, a panel of experts identified the trends and issues shaping the demand for and supply of academic food-animal veterinarians, then forecasted the likely future demand and shortages of food-supply veterinarians employed in academic institutions in the United States and Canada through 2016. The results indicate that there will be increasing future demand and persistent shortages of academic food-supply veterinarians unless current trends are countered with targeted, strategic action. The Delphi panel also evaluated the effectiveness of several strategies for reversing current trends and increasing the number of food-supply veterinarians entering into academic careers. Academic food-supply veterinarians are a key link in the system that produces food-supply veterinarians for all sectors (private practice, government service, etc.); shortages in the academic sector will amplify shortages wherever food-supply veterinarians are needed. Even fairly small shortages have significant public-health, food-safety, animal-welfare, and bio-security implications. Recent events demonstrate that in an increasingly interconnected global economic food supply system, national economies and public health are at risk unless an adequate supply of appropriately trained food-supply veterinarians is available to counter a wide variety of threats ranging from animal and zoonotic diseases to bioterrorism.     

Physiologic VDD versus nonphysiologic VVI pacing in canine 3rd-degree atrioventricular block

Historically, ventricular demand, nonphysiologic (VVI) pacing has been the most commonly used modality to treat 3rd-degree atrioventricular (AV) block. The goal of this study was to determine the feasibility of using a commercial, single-lead, physiologic (VDD) pacemaker in dogs with 3rd-degree AV block. Furthermore, we hoped to characterize and identify differences in the radiographic, echocardiographic, neurohormonal, and quality of life consequences of physiologic versus nonphysiologic pacing. We evaluated 10 dogs during a 12-week crossover study. Acutely, rate-matched physiologic pacing reduced pulmonary capillary wedge pressure by 19% compared with nonphysiologic pacing. VDD pacing significantly reduced left atrial size normalized to body weight, left atrial-to-aortic root ratio, and left ventricular end-systolic dimension and increased fractional shortening, aortic Doppler velocity, cardiac output, and stroke volume compared with VVI pacing. Variable rate VDD pacing resulted in a significantly slower heart rate (HR) during echocardiography than fixed-rate (100 bpm) VVI pacing. AV synchronous pacing reduced circulating N-terminal proatrial natriuretic peptide (ANP), norepinephrine (NOR), and epinephrine (EPI) concentrations compared with asynchronous pacing. There were no significant differences in systemic blood pressure, thoracic radiographs, or owner-perceived quality of life. The median percentage of AV synchronous pacing during the VDD modality was 99.8% (range, 1.2 to 99.9%). This study confirms the potential to achieve physiologic pacing with a commercial, single-lead system in dogs. VDD pacing improved hemodynamics and neurohormonal profiles over asynchronous pacing although the long-term clinical benefits of these changes remain to be determined.