CVMA | Table of Contents and Abstracts

Table of Contents and AbstractsJanuary 2020, Vol. 84, No. 1

Review Articles

Carbapenemase-producing Enterobacteriaceae in animals and methodologies for their detection

Rebecca E.V. Anderson, Patrick Boerlin (page 3)

Carbapenemase-producing bacteria are difficult to treat and pose an important threat for public health. Detecting and identifying them can be a challenging and time-consuming task. Due to the recent rise in prevalence of infections with these organisms, there is an increased demand for rapid and accurate detection methods. This review describes and contrasts current methods used for the identification and detection of carbapenemase-producing bacteria to help control their spread in animal populations and along the food chain. The methods discussed include cultures used for screening clinical samples and primary isolation, susceptibility testing, culture-based and molecular confirmation tests. Advantages and disadvantages as well as limitations of the methods are discussed.


Prevalence and mutation analysis of the spike protein in feline enteric coronavirus and feline infectious peritonitis detected in household and shelter cats in western Canada

Laura A. McKay, Melissa Meachem, Elisabeth Snead, Terri Brannen, Natasha Mutlow, Liz Ruelle, Jennifer L. Davies, Frank van der Meer (page 18)

Feline infectious peritonitis (FIP) is a fatal disease for which no simple antemortem diagnostic assay is available. A new polymerase chain reaction (PCR) test has recently been developed that targets the spike protein region of the FIP virus (FIPV) and can identify specific mutations (M1030L or S1032A), the presence of which indicates a shift from feline enteric coronavirus (FeCV) to FIPV. This test will only be useful in the geographical region of interest, however, if the FIP viruses contain these mutations. The primary objective of this study was to determine the presence of the M1030L or S1032A mutations in FeCV derived from stool samples from a selected group of healthy cats from households and shelters and determine how many of these cats excrete FeCV. The secondary objective was to evaluate how often these specific FIPV mutations were present in tissue samples derived from cats diagnosed with FIP at postmortem examination. Feline enteric coronavirus (FeCV) was detected in 46% of fecal samples (86/185), all were FeCV type 1, with no difference between household or shelter cats. Only 45% of the FIPV analyzed contained the previously reported M1030L or S1032A mutations. It should be noted that, as the pathological tissue samples were opportunistically obtained and not specifically obtained for PCR testing, caution is warranted in interpreting these data.

Fluoroscopic and radiographic assessment of variations in tracheal height during inspiration and expiration in healthy adult small-breed dogs

Grégoire Scherf, Isabelle Masseau, Anne-Sophie Bua, Guy Beauchamp, Marilyn E. Dunn (page 24)

The objective of this study was to document tidal variations in tracheal height during normal respiration in 19 healthy adult (> 1 y old) small-breed dogs (< 10 kg) using fluoroscopy and radiography. Each dog underwent tracheal fluoroscopic examination on inspiration and expiration while in a standing position (F-S) and in right lateral recumbency (F-RL), followed by radiographic projections obtained in right lateral recumbency. The percent variation in tracheal height during maximal inspiration and expiration was determined at 3 different locations [cervical region (CR), thoracic inlet (TI), and intrathoracic (IT) region]. When all imaging procedures and sites of measurement were considered, tracheal height varied during physiologic inspiration and expiration from 0% to 21.1%, with a mean of 4.5%. The mean percent variation in tracheal height was not significantly different among imaging modalities (F-S versus F-RL versus radiography) (P = 0.16) or measurement sites (CR versus TI versus IT) (P = 0.89). The body condition score (BCS) (P = 0.96), age (P = 0.95), and breed (P = 0.19) did not significantly influence the mean percent variation in tracheal height. The average variation in tracheal height during maximal physiological inspiration and expiration is small (< 6%) in most healthy adult small-breed dogs as assessed by fluoroscopy and radiography, although tracheal height may vary by as much as 21.1% in some healthy individuals. Inspiratory and expiratory radiographs acquired in right lateral recumbency provide an accurate assessment of tracheal height as an alternative to fluoroscopy.

Comparison of 3 intraosseous catheter sites and methods of determining placement success in cadaver rabbits

Christopher R. Kennedy, Jay N. Gladden, Elizabeth A. Rozanski (page 33)

The study goals were to determine if intraosseous (IO) catheters can be placed with greater success into the humerus, femur, or tibia of cadaver rabbits, and to evaluate the accuracy of perceived success (PS) and objective clinical success (OCS) criteria against true intramedullary catheterization confirmed by fluoroscopy. This was a prospective study utilizing 12 rabbit cadavers. Twenty-two participants attempted IO catheter placement at 3 sites. Perceived success, OCS, and fluoroscopic true success (FTS) were recorded. A Fisher’s exact test was used to compare PS, OCS, and FTS, and FTS rates between sites (P < 0.05). A Wilcoxon test was used to compare speed of placement (P < 0.05). Overall, of 66 attempts, PS was reported in 86.4%, OCS was documented in 62.1%, FTS was confirmed in 43.9%. Perceived success and OCS overestimated FTS (P ≤ 0.01 and P = 0.027, respectively). Confirmation of FTS occurred in 10/22 (45.5%) humeral, 5/22 (22.7%) femoral, and 14/22 (63.6%) tibial (P = 0.03) attempts.

Median time until placement for the humerus was 37.5 seconds (range: 15 to 125 seconds); the femur 135 seconds (range: 91 to 148 seconds); the tibia 49 seconds (range: 19 to 150 seconds). The humerus and tibia were faster to catheterize than the femur (P = 0.01 and 0.03, respectively). Participant PS and OCS criteria overestimated FTS. The humerus or tibia may be more successful and are faster to catheterize.

Effects of a single paracetamol injection on the sevoflurane minimum alveolar concentration in dogs

Paula González-Blanco, Susana Canfrán, Rubén Mota, Ignacio A. Gómez de Segura, Delia Aguado (page 37)

This study aimed to determine the effect of a single injection of paracetamol on the sevoflurane minimum alveolar concentration (MAC) response to noxious mechanical stimulation. Seven healthy adult beagles were enrolled in a prospective, randomized, blinded, crossover experimental study. Anesthesia was induced with propofol [11.6 ± 2.4 mg/kg body weight (BW)] and maintained with sevoflurane. The MAC was determined before (MAC-1) and after (MAC-2) treatment with 15 mg/kg BW of intravenous (IV) paracetamol or saline over 15 minutes. Samples for plasma paracetamol determination were collected immediately after IV treatment administration and following MAC-2 determination (123 ± 27 minutes after starting paracetamol administration). The MAC-1 was similar between treatments (1.7% ± 0.4%). There were no differences between control and paracetamol groups at MAC-2 (2.0% ± 0.4% and 1.7% ± 0.5%, respectively; P = 0.285). Paracetamol plasma concentrations after paracetamol administration were 34.5 ± 9.9 µg/mL, decreasing at the end of the procedure (8.5 ± 4.2 µg/mL). In conclusion, 15 mg/kg BW of IV paracetamol did not significantly reduce sevoflurane MAC in healthy dogs.

Correlation of activity data in normal dogs to distance traveled

Bishoy S. Eskander, Megan Barbar, Richard B. Evans, Masataka Enomoto, B. Duncan X. Lascelles, Michael G. Conzemius (page 44)

The objective of this study was to explore the mathematical relationships between independent variables (patient morphometrics and treadmill speed) and dependent variables (accelerometer or pedometer output) when evaluating data from accelerometers and pedometers in dogs. Twenty dogs took part in 3 randomized activities, consisting of exercise on a treadmill at 1.0, 1.5, and 2.0 m/s for a total distance of 1 km at each speed. Dogs simultaneously wore both an accelerometer and a pedometer. Statistical analysis used multiple regression models to discover the relationships between independent and dependent variables. A formula was developed to predict the distance traveled by a dog based on its morphometrics and activity monitor output. Shoulder height had stronger correlations to accelerometer and pedometer outputs than other morphometric variables. As shoulder height increased, all accelerometer and pedometer outputs decreased. As treadmill speed increased, both accelerometer and pedometer step counts decreased, while accelerometer activity counts increased. According to a formula derived to predict the total distance traveled using patient shoulder height and accelerometer or pedometer output, pedometer steps were the most accurate predictor of distance traveled. Accelerometer steps were less accurate when using the same model. Accelerometer activity counts did not reveal a meaningful predictive formula. The results of this study indicate that patient morphometrics and treadmill speed (as a measure of intensity) influenced accelerometer and pedometer data. The pedometer data more precisely and accurately estimated the distance traveled based on step counts and patient shoulder height. In normal dogs, accelerometer and pedometer steps may reasonably estimate distance traveled.

Differences in the relative counts of peripheral blood lymphocyte subsets in various age groups of pigs

Olga Pietrasina, Julia Miller, Anna Rzasa (page 52)

The aim of the study was to determine age-related changes in peripheral blood lymphocytes in pigs. Previous studies looking at age-related differences in lymphocyte subsets in porcine blood have not established reference ranges for these parameters. Moreover, most studies have concentrated on the dynamic changes in the first months of life, failing to continue observations in older animals. Therefore, in the present study, relative counts of various lymphocyte subpopulations (cytotoxic and helper T-cells, B-cells, and γδ T-cells) were evaluated to characterize the development of the cellular immune system at 28, 35, 135, and 200 days of age in growing pigs and adult sows (i.e., first and subsequent parity). In all examined groups, CD3+ cells constituted the largest percentage of cells. A statistically significant higher percentage of TCRγδ+CD3+ was noted in fatteners and gilts in comparison to other age groups. These results may be a reflection of antigenic pressure and show an immune response to viral or bacterial agents/environmental microbism.

Determination of urokinase-type plasminogen activator serum levels in healthy and oncologic cats

Cláudia Viegas, Augusto J. de Matos, Liliana R. Leite-Martins, Inês Viegas, Rui R. F. Ferreira, Hugo Gregório, Andreia A. Santos (page 60)

The urokinase plasminogen activator system (uPAS) has been poorly investigated in veterinary oncology. The aim of this study was to determine uPA serum concentrations in healthy and oncologic cats to understand the potential value of uPA as a cancer biomarker. Serum samples were collected from 19 healthy cats and 18 cats with spontaneous malignant neoplasms and uPA was measured through a specific enzyme-linked immunosorbent assay kit. The differences between uPA values and their relation with intrinsic factors and clinicopathological parameters were analyzed using an analysis of variance (ANOVA) and independent t-test. The average serum concentration of uPA in cancerous cats (0.54 ± 0.22 ng/mL) differed from that of healthy cats (1.10 ± 1.16 ng/mL) but was not significantly influenced by cats’ clinicopathological parameters or by the presence of metastases. This study describes, for the first time, the serum concentrations of uPA in cats and proposes directions for future studies to uncover the relevance of uPAS in feline carcinogenesis.

Antioxidative enzyme activity and total antioxidant capacity in serum of dogs with degenerative mitral valve disease

Marcin Michalek, Aleksandra Tabis, Alicja Cepiel, Agnieszka Noszczyk-Nowak (page 67)

This study was designed to evaluate the antioxidative status of serum by measuring its total antioxidant capacity, as well as the antioxidant enzyme activity (superoxide dismutase, catalase, and glutathione reductase), in dogs with various stages of degenerative mitral valve disease (DMVD) compared to healthy controls. In total, 71 client-owned dogs in different stages of DMVD, which included healthy controls, took part in the study. Following an anamnesis, clinical examination, standard transthoracic echocardiograpic examination, chest X-ray, complete blood (cell) count, and serum biochemistry, dogs were divided into 2 study groups. Blood was drawn from each dog once at the time of presentation and selected antioxidant parameters were measured using commercially available assay kits. The activity of superoxide dismutase gradually decreased in the more advanced stages of DMVD, while the activity of catalase was significantly higher in the group of dogs with asymptomatic DMVD compared to healthy controls and dogs with symptomatic DMVD. No significant changes were noted in total antioxidant capacity and the activity of glutathione reductase. Results suggested that DMVD has a significant impact on the activity of superoxide dismutase and catalase in the serum of the tested dogs. Knowledge of changes in the activity of antioxidative enzymes may warrant further studies, possibly to evaluate the potential role of compounds with antioxidative properties in the clinical outcome of dogs with DMVD.

Brief Communications

Alterations in serum protein electrophoresis profiles during the acute phase response in dogs with acute pancreatitis

Ji-Seon Yoon, Suhee Kim, Jin-Hee Kang, Jinho Park*, DoHyeon Yu* (page 74)

The quantification of serum proteins is a useful tool for diagnosing and monitoring various diseases that involve changes in the concentrations of these proteins. As canine acute pancreatitis (AP) accompanies the systemic inflammatory response syndrome, serum proteins such as C-reactive protein (CRP) have been used as inflammatory markers for dogs with AP. The goal of this study was to investigate the overall profiles of serum proteins by serum protein electrophoresis (SPE) and to determine the concentration of acute phase proteins (APPs) in dogs with AP in order to better understand serum protein profiles as diagnostic markers in these dogs. Decreased levels of albumin and increased levels of alpha-2 globulin were observed in dogs with AP by SPE. Among APPs, elevated concentrations of CRP, serum amyloid A (SAA), and haptoglobin were detected. The concentration of SAA was positively correlated with that of CRP, which suggests that SAA could be a sensitive marker of inflammation in dogs with AP, similar to CRP.

Serum paraoxonase-1 activity in tail and mammary veins of ketotic dairy cows

Rika Fukumori, Hanan K. Elsayed, Masahito Oba, Yasumitsu Tachibana, Ken Nakada, Shin Oikawa (page 79)

The objective of this study was to evaluate the association between ketonemia and serum paraoxonase-1 (PON1), malondialdehyde (MDA), and other blood components in tail and mammary veins of dairy cows. Forty-two Holstein dairy cows with decreased feed intake were divided into HIGH (≥ 1.2 mM; n = 31) and LOW (< 1.2 mM; n = 11) groups based on the β-hydroxybutyrate concentration in plasma collected from the tail vein. The HIGH group had a significantly greater plasma non-esterified fatty acid (NEFA) concentration, but significantly lower serum PON1 activity and phospholipid concentration, and a tendency to have a lower cholesterol ester concentration than the LOW group. Serum PON1 activity was not correlated with the MDA concentration but was positively correlated with serum concentrations of cholesterol esters and phospholipids, and negatively correlated with the plasma NEFA concentration. These results suggest that serum PON1 activity is reduced by hyperketonemia and the relevance of PON1 to MDA seems to not be direct, though it is involved.