Effect of needle gauge on pain and specimen quality of ultrasound-guided fine needle sampling without aspiration of the canine spleen.

Modifications of splenic parenchyma are common ultrasonographic findings in dogs. Splenic fine needle aspiration (FNA) is a rapid, safe procedure, routinely performed in veterinary institutions. However, 22-gauge (G) needle usually reported is selected according to general practice and the most appropriate needle size to be used remains unclear. The aim of this prospective, single-center, methods comparison study was to assess the effect of needle size on cytologic specimens' evaluation and animal welfare during the procedure. Dogs underwent ultrasound-guided splenic FNA using 23, 25, and 27G needles. Needles were compared based on initial and then detailed cytologic evaluation. The initial evaluation assessed overall cellularity, cell preservation, hemodilution, and detailed cytologic evaluation referred to exhaustive splenic components. Welfare evaluation was performed based on a scoring system. A total of 54 dogs were included in this study with 54 of 54 welfare evaluations and 35 of 54 cytologic evaluations by one or two European College of Veterinary Clinical Pathology-certified cytologists. The final cytologic diagnosis was unchanged regardless of the needle size. For the initial evaluation, 23G needles provided significantly higher cellularity than the 27G needles. For detailed cytologic evaluation, only the richness in mesothelial cells and stroma was affected by needle size. Pain induced by the procedures was considered low using 23, 25, and 27G needles with the 27G needle producing the least adverse reactions. Findings from the current study supported using needle gauges smaller than the previously published standard 22G needle for spleen ultrasound-guided fine needle nonaspiration in dogs. Due to higher cellularity and lower pain scores, authors recommend the use of 23G needles with a nonaspiration technique.

Ultrasonographic findings may be useful for differentiating interdigital abscesses secondary to migrating grass awns and interdigital furunculosis in dogs.

Grass awn migration and furunculosis are common diseases in dogs that can lead to interdigital subcutaneous lesions with a similar clinical presentation, and occasionally similar ultrasonographic images, but different treatments are required. This retrospective, multicentric, analytical study aimed to determine whether epidemiological, clinical, and ultrasonographic features could be used to differentiate interdigital furunculosis and abscesses secondary to migrating grass awns. Fifty-nine dogs that underwent interdigital ultrasonography were included (interdigital furunculosis [IDF], n = 27; interdigital abscess secondary to a migrating grass awn [IAGA], n = 32). Ultrasonographic images were reviewed by two observers blinded to the diagnosis, who graded nine qualitative and four quantitative parameters for each patient. In both groups, pruritus/licking (IDF 74%, IAGA 70%), a discharging interdigital wound (63% for each group), and thoracic limb involvement (IDF 88%, IAGA 75%) were common features. On ultrasound, a subcutaneous multilinear hyperechoic main element was identified in most dogs (IDF 85%, IAGA 100%). The ability to display this element in a single plane (P < 0.01), the absence of additional hyperechoic linear elements in different planes (P < 0.01), and a surrounding hypoechoic halo (P < 0.05) were significantly more common in dogs with interdigital abscesses secondary to migrating grass awns. A cut-off value of 0.83 cm for the length of the main multilinear element provided a sensitivity of 91% and a specificity of 87% in the diagnosis of a migrating grass awn. Findings supported prioritizing a differential diagnosis of interdigital abscesses secondary to grass awns in dogs with these ultrasonographic characteristics.

Ultrasonographic characteristics of the portal venous system of 37 healthy, unsedated, student-owned cats: A prospective study.

Objective: The aim of this study was to determine portal vein and divisional branch diameters and portal vein velocities in healthy, unsedated cats, using B-mode and Doppler ultrasound. Animal: Thirty-seven healthy, adult cats, all owned by students. Procedure: Enrollment of cats in the study was done prospectively. Ultrasonographic imaging in both the longitudinal and transverse planes was assessed, with all examinations and measurements done by the same person. The assessment included the following 3 sites: extra-hepatic portion of the portal vein, intra-hepatic branches of the portal vein, and the aorta at the level of the porta hepatis. The Shapiro-Wilk test was used for normality and P < 0.05 was used to define statistical significance. Results: Both the extra-hepatic portion of the portal vein and the porta hepatis were identified in all 37 cats (100%), whereas the aorta was recorded in 31 (84%), and the left and right intra-hepatic branches of the portal vein were seen in 29 (78%). Pulsed-wave Doppler ultrasound of the portal vein was obtained in 32 cats (86%). In longitudinal view, average maximal diameter of the extra-hepatic portal vein was 3.6 mm (± 0.7 mm), and the mean portal flow velocity was 14.6 cm · s (± 4.3 cm · s). In transverse view, average maximal diameter was 4.8 mm (± 0.8 mm) for the extra-hepatic portal vein, and 3.1 mm (± 0.8 mm) and 2.6 mm (± 0.7 mm) for the left and right intra-hepatic branches, respectively. The portal-vein-to-aorta ratio averaged 1.2 (± 0.2). Conclusion: This study produced sonographic data of the portal venous system in healthy, conscious adult cats, which may be useful during investigation of liver diseases, including congenital and acquired liver diseases.

Caractéristiques échographiques du système porte hépatique chez 37 chats domestiques, sains et non sédatés. Objectif: Cette étude a évalué plusieurs paramètres échographiques de la veine porte chez des chats sains, en échographie conventionnelle et Doppler. Animaux: Trente-sept chats adultes sains non-sédatés appartenant à des étudiants vétérinaires. Procédure: L'ensemble des chats ont été recrutés de manière prospective. Des plans de coupes échographiques longitudinaux et transverses ont été évalués, et les mesures échographiques ont été réalisées par un unique investigateur. Trois régions anatomiques ont été évaluées, dont la portion extra-hépatique de la veine porte, les rameaux portes intra-hépatiques, ainsi que l'aorte, au niveau de la porte hépatique. Le test de Shapiro-Wilk a été utilisé pour évaluer la distribution des variables, et une valeur P de 0,05 a été utilisée pour définir la signification statistique des résultats. Résultats: La porte hépatique et la portion extra-hépatique de la veine porte ont été identifiés chez 37 chats (100 %), l'aorte a été visualisés chez 31 chats (84 %), et les rameaux portes intra-hépatiques ont été visualisés chez 29 chats (78 %). Des images échographiques Doppler de la veine porte ont été obtenues chez 32 chats (86 %). En coupe longitudinale, le diamètre maximal de la portion extra-hépatique de la veine porte était de 3,6 mm (± 0,7 mm), et la vitesse du flux sanguin portal était de 14,6 cm · s (± 4,3 cm · s). En coupe transverse, le diamètre maximal était de 4,8 mm (± 0,8 mm) pour la portion extra-hépatique de la veine porte, et respectivement de 3,1 mm (± 0,8 mm) et 2,6 mm (± 0,7 mm) pour les rameaux intra-hépatiques gauche et droit. Le ratio veine porte : aorte était de 1,2 (± 0,2). Conclusion: Cette étude fournit des intervalles de valeurs échographiques du système vasculaire porte hépatique chez le chat sain non-sédaté, ce qui peut s'avérer utile lors d'investigations diagnostiques, notamment la recherche de maladies hépatiques congénitales ou acquises.(Traduit par les auteurs).

Anatomical and ultrasonographic study of the femoral nerve within the iliopsoas muscle in beagle dogs and cats.

OBJECTIVES: An ultrasound (US)-guided ventral suprainguinal approach to block the femoral nerve (FN) within the iliopsoas muscle (IPM) has recently been described in dogs. The goal of the present study was to provide the operator with additional information to locate the FN within the IPM in dogs and cats using US. STUDY DESIGN: The study was carried out in three phases: a dissection of the FN (phase 1); an in vivo US-assisted nerve study (phase 2), and an anatomical cross-sectional study (phase 3). ANIMALS: Nine healthy adult beagle dogs and nine healthy adult cats. METHODS: Dissections were performed to investigate the anatomical characteristics of the FN and its related structures in one dog and one cat. Ultrasound scans of the left and right FN were performed in eight dogs and eight cats. The FN diameter and the distance between the FN and the external iliac artery (EIA) in US images and in anatomical cryosections were measured. RESULTS: The median FN diameter did not differ significantly between cats and dogs (1.1 mm versus 1.0 mm) or between the two techniques (US versus anatomical cross-sectional study) (1.1 mm versus 1.1 mm in dogs; 1.0 mm versus 1.1 mm in cats). The US and anatomical measurements of the median distances between the FN and EIA differed significantly between dogs and cats (8.2 mm versus 5.8 mm by US; 5.7 mm versus 4.8 mm in the anatomical study). CONCLUSIONS AND CLINICAL RELEVANCE: The distance between the EIA and FN is reproducible in beagle dogs and cats and can be used in locating the FN within the IPM.

Improving the Quality of EDTA-treated Blood Specimens from Mice.

Nonterminal blood sampling in laboratory mice is a very common procedure. With the goal of improving animal welfare, different sampling sites and methods have been compared but have not achieved a consensus. Moreover, most of these studies overlooked the quality of blood specimens collected. The main preanalytical concern with EDTA-treated blood specimens for hematology analyses is platelet aggregation, which is known to cause analytical errors. Our objective was to find a nonterminal blood sampling method with minimal adverse effects on mice and few or no platelet aggregates. We tested and compared 2 collection sites, 4 sampling methods, and 3 antithrombotic drugs in 80 C57BL6/j male and female mice by evaluating platelet aggregates on blood smears and platelet, WBC, and RBC counts. In addition, the blood collection process was carefully evaluated, and adverse effects were recorded. Platelet aggregation was lower in specimens collected from the jugular vein than from the facial vein, with no effect of the sampling device or the presence of an antithrombotic additive. Highly aggregated specimens were significantly associated with lower platelet counts, whereas aggregation had no effect on WBC or RBC counts. Adverse events during sampling were significantly associated with more numerous platelet aggregates. The jugular vein is thus a satisfactory sampling site in mice in terms of both animal welfare and low platelet aggregation. Using antithrombotic agents appears to be unnecessary, whereas improving sampling conditions remains a key requirement to ensure the quality of EDTA-treated blood specimens from mice.

Laparoscopic-assisted colopexy and sterilization in male dogs: short-term results and physiologic consequences.

OBJECTIVE: To describe laparoscopic-assisted colopexy and sterilization, and evaluate outcome and effects in healthy male dogs. STUDY DESIGN: Experimental study. ANIMALS: Male Beagle dogs (n=7). METHODS: A laparoscopic-assisted, extracorporeally sutured colopexy, and sterilization by ligation and section of the testicular vessels and ductus deferens were evaluated 11 weeks after surgery. Ex vivo tensile tests were performed on the colopexy sites and loss of testicular function was assessed by monitoring serum testosterone, and by ultrasonographic and histologic examinations of the testes. Systemic inflammation and potential iatrogenic colonic functional disorders were investigated by monitoring serum C-reactive protein (CRP) in the perioperative period and from a sulfapyridine (SP) kinetic profile obtained before and 10 weeks after surgery. RESULTS: No intraoperative complications were recorded and clinical outcome was considered fair in all dogs. A mean tensile force of 42 N was required to disrupt colopexies. No relevant postoperative increase in CRP concentrations or changes in SP kinetics were observed. Testicular function was lost. CONCLUSIONS: Laparoscopic-assisted colopexy achieved adhesion of the colon to the abdominal wall and testicular endocrine function and spermatogenesis were eliminated by laparoscopic castration.

Reference Values for Hematology, Plasma Biochemistry, Bone Marrow Cytology and Bone Histology of NOD.Cg-Prkdcscid Il2rgtm1Wjl/ SzJ Immunodeficient Mice.

Highly immunodeficient NSG mice (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) are commonly used as a models in preclinical studies for patient-derived engraftment. However, despite the frequency of their use, reference values for their clinical pathology markers have not been determined. In accordance with the American Society of Veterinary Clinical Pathology (ASVCP) recommendations, we established de novo reference values for hematologic and biochemical variables and evaluated bone marrow cytology and histology in forty 9-wk-old male and female NSG mice. Hematologic analyses were performed using 2 separate analyzers (IDEXX ProCyte Dx, Sysmex XT-2000iV) and biochemical values were measured using a Scil VetScan2. The primary hematologic characteristic seen in NSG mice was a very low white blood cell (WBC) count (below 1.6 109/L). Lymphocyte and monocyte counts were respectively over- and under-estimated by the analyzers, as compared with manual counts, likely due to misidentification of the very low concentrations of these cell types by the analyzers. This analytical bias highlights the need for confirmatory microscopic observation of blood smears from these mice for WBC differential identification. Results for all other hematology and biochemistry variables were similar to those previously reported in inbred mice, except for MPV and an unexpectedly high glucose concentration (11.5 to 19.0 mmol/L), potentially due to the nonfasting status of the animals. The differential bone marrow cell count and Myeloid:Erythroid ratio (median 1.76) were also established. Megakaryocyte and adipocyte count differed significantly between the femoral diaphysis and metaphysis and between genders. These results provide a reliable resource of baseline data for hematologic variables for researchers monitoring graft rejection studies in NSG mice.

Abnormal Sysmex XT-2000iV DIFF scattergram in a cat with a prominent mastocytemia.

A 2-year-old neutered male domestic shorthair cat was presented to the emergency service of the National Veterinary School of Toulouse (France) for acute vomiting and diarrhea with lethargy, inappetence, and adypsia for the past 48 hours. Complete blood counts were performed with the ProCyte DX at the emergency department and with the Sysmex XT-2000iV at the laboratory 2 weeks later. The scattergrams from the two analyzers revealed similar unusual and abnormal dot plots. The Sysmex XT-2000iV DIFF scattergram also showed no clear separation between different leukocyte populations. The eosinophil cluster was in an abnormal location compared with that of the "typical" location in a normal cat. A blood smear evaluation revealed the presence of numerous mast cells. Thus, we hypothesized that the Sysmex XT-2000iV had detected the mast cell population, and this led to errors in the differential counts. To explore this hypothesis, we manually gated on the DIFF scattergram and performed a manual differential on the blood smear. With this new gating strategy, the Sysmex XT-2000iV and manual differentials were similar. Thus, in the case of systemic mastocytosis, mast cells can be located between the lymphocyte, monocyte, and eosinophil clusters on scattergrams.

The effects of storage at 4°C and 20°C on the hemograms of C57BL/6 mice and Wistar rats using the IDEXX ProCyte Dx and blood smear evaluations.

BACKGROUND: Delayed blood analysis might be unavoidable in laboratory practice, but little is known about rodent blood stability, especially cell morphology and scattergram results. OBJECTIVES: This study aimed to evaluate the stability of rodent blood cell counts and morphologies at different temperatures using the ProCyte Dx analyzer and performing manual observations. METHODS: Ten Wistar rats and 10 C57bl/6 mice were sampled on EDTA tubes and aliquoted for storage (4°C, 20°C). Hematologic analyses were performed immediately and at T6h, T24h, T48h (rats and mice), and T72h (rats only) after storage. RESULTS: In rats, at any temperature, red blood cell counts, hemoglobin concentrations (HGB), mean corpuscular hemoglobin (MCH) levels, and reticulocyte, white blood cell (WBC), eosinophil, and impedance platelet counts remained stable over time. The main changes were observed at 20°C for hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and WBC differential counts. Optical platelet counts (PLT-O) and platelet variables underwent changes at both temperatures from T24h. In mice, red blood cell counts by impedance (RBC-I), MCH, and WBC, lymphocyte, eosinophil, and platelet counts, and plateletcrit (PCT) were stable over time and at all temperatures. As in rats, the most significant changes were observed at 20°C and concerned the optical RBC (RBC-O) counts, HCTs, MCVs, MCHCs, and reticulocyte, neutrophil, and monocyte counts. For both species, blood cell morphologies were altered from T24h at all temperatures, and platelet clumps were more numerous at 4°C. CONCLUSIONS: When rodent blood analyses need to be delayed, storage at 4°C is preferred and should not exceed 24 hours. PLT counts should be interpreted cautiously in refrigerated specimens with mandatory blood smear evaluations when abnormal scattergrams are observed.

Effects of storage conditions on results for quantitative and qualitative evaluation of proteins in canine urine.

OBJECTIVE To investigate effects of storage conditions on the canine urine protein-to-creatinine ratio (UPC) and on SDS-agarose gel electrophoresis (AGE) of urinary proteins. SAMPLE Urine specimens from 20 proteinuric (UPC > 0.5) and 20 nonproteinuric (UPC ≤ 0.2) dogs. PROCEDURES UPC and SDS-AGE were performed on urine specimens stored at room temperature (20°C) and 4°C for up to 5 days and at -20° and -80°C for up to 360 days; some specimens were subjected to 3 freeze-thaw cycles. Results were compared with those obtained for fresh urine specimens. RESULTS UPC was not affected by storage at room temperature or by freezing. A decrease in UPC was observed for specimens from nonproteinuric dogs after 5 days at 4°C (10%) and from both groups after 90 days at -20° and -80°C (≤ 20% and ≤ 15%, respectively). The SDS-AGE profiles revealed no visual changes regardless of duration of storage for specimens stored at room temperature, 4°C, and -80°C, except for 1 profile after 360 days at -80°C. Repeated freeze-thaw cycles did not affect SDS-AGE profiles. Appearance or strengthening of high-molecular-weight bands that could alter interpretation was evident in SDS-AGE profiles after storage at -20°C for ≥ 15 days (31/40 dogs). CONCLUSIONS AND CLINICAL RELEVANCE Storage of urine at -20° or -80°C for up to 1 year influenced the UPC without affecting clinical interpretation. Storage of urine specimens at -20°C impaired visual analysis of SDS-AGE. When SDS-AGE cannot be performed on fresh or recently refrigerated urine specimens, storage at -80°C is recommended.

Within-day and between-day variability of blood pressure measurement in healthy conscious Beagle dogs using a new oscillometric device.

OBJECTIVES: The main objective of this study was to determine the within- and between-day variability of blood pressure measurement in dogs using an oscillometric device, pet-MAP. ANIMALS, MATERIALS AND METHODS: Five healthy conscious adult Beagle dogs were used. The dogs were presented in a random order for examinations and the investigators were blinded to the dogs. Blood pressure was measured using a standardized procedure. Three investigators with the same level of experience, trained for 1 h with pet-MAP the day before starting the study, performed 480 blood pressure measurements in 5 healthy conscious dogs on two different days. RESULTS: The within- and between-day CVs for systolic blood pressure were 9.0-10.1% and 12.8-16.4%, respectively. The corresponding SD values were 14.7-16.6 mm Hg and 21.0-27.1 mm Hg respectively. For diastolic blood pressure, the within- and between-day CVs were 10.3-14.4% and 14.2-24.9% respectively. The corresponding SD values were 9.7-13.9 mm Hg and 13.0-24.0 mm Hg. CONCLUSIONS: The within- and between-day CVs for systolic blood pressure, measured with pet-MAP by investigators with a minimal period of training, seem to be acceptable in Beagle dogs without hypertension or hypotension. This study suggests that, using this device, one investigator can be replaced by another under the described circumstances.