Table of Contents and AbstractsOctober 2018, Vol. 82, No. 4


Oscillometric and Doppler arterial blood pressure measurement in conscious goats

Olga Szalus-Jordanow, Michal Czopowicz, Anna Swierk, Oktawia Szpinda, Magdalena Garncarz, Marcin Mickiewicz, Agata Moroz, Emilia Bagnicka, Jaroslaw Kaba (page 244)

The objective of this study was to characterize arterial blood pressure (BP) measurements obtained by using 2 indirect methods, oscillometry and Doppler ultrasonic sphygmomanometry, in conscious goats. Agreement between systolic BP yielded by these 2 methods was then assessed. Sixty female dairy goats aged from 1.5 to 11.8 y (median: 5.5 y) were examined in a standing position with a cuff placed on the tail. All goats had a severe arthritic form of caprine arthritis-encephalitis. Three to 5 repeated measurements of each BP type were averaged for each goat and considered as a final measurement. With oscillometry, systolic blood pressure (O-SBP), diastolic blood pressure, and mean blood pressure, as well as heart rate (HR) were measured, while only systolic blood pressure was measured with Doppler (D-SBP). The O-SBP did not correlate with D-SBP [correlation coefficient (r) = 0.24, P = 0.067]; the mean difference (± standard deviation) was 24.5 ± 26.3 mmHg and limits of agreement were from −27.2 mmHg [95% confidence interval (CI): −39.0, −15.4 mmHg] to 76.1 mmHg (95% CI: 64.3, 87.9 mmHg). No significant linear correlation was found between any BPs and HR (r: −0.10 to 0.22) or age (r: −0.26 to 0.07) of the goats. The study showed that, while BP could be measured in conscious goats using both oscillometry and Doppler ultrasonic sphygmomanometry, the results obtained were so inconsistent that these methods could not be used interchangeably.

Salmonella fecal shedding in pigs from birth to market and its association with the presence of Salmonella in palatine tonsils and submandibular lymph nodes at slaughter

Margaret H. Ainslie-Garcia, Abdolvahab Farzan, Jane E. Newman, Robert M. Friendship, Brandon N. Lillie (page 249)

Salmonella is an important cause of foodborne illnesses in humans. Food-producing animals, including swine, are a major source of Salmonella in food products. This study investigated on farm Salmonella fecal shedding in pigs at different production stages — from weaning to marketing — and its association with the presence of Salmonella in tissues at slaughter. Fourteen groups from 8 commercial farrowing sources (N = 809 pigs) were monitored 5 times from birth to slaughter. Fecal and tissue samples were collected from pigs and cultured for Salmonella. A survey was conducted to collect farm management information. A multi-level mixed-effects logistic regression modelling method was used to analyze Salmonella shedding over time and the association between Salmonella shedding and the presence of Salmonella in tissue samples. Salmonella was recovered from 13% (421/3339) of fecal samples collected from 809 pigs over the course of the study. Overall, 35% (284) of pigs shed Salmonella at least once, while 12% (99) shed more than once. Salmonella shedding increased as pigs aged (P = 0.01) and increased in the summer months (P < 0.01). Salmonella was isolated from tissue samples collected from 23% (134/580) of pigs; however, the presence of Salmonella at slaughter was not associated with on farm shedding. The seasonal trend in Salmonella shedding and its association with age may be used to identify high-risk groups and implement more effective control measures accordingly. The identification of repeat shedders warrants interventions that target this source of infection on swine farms.

Molecular epidemiology, antimicrobial susceptibility, and pulsed-field gel electrophoresis genotyping of Pseudomonas aeruginosa isolates from mink

Yongda Zhao, Lili Guo, Jie Li, Binghu Fang, Xianhui Huang (page 256)

Pseudomonas aeruginosa is an important animal pathogen and contributes to hemorrhagic pneumonia in mink. Between April 2011 and December 2016, samples of lung, liver, and spleen were collected from mink with this disease on 11 mink farms in 5 Chinese provinces. From these samples, we obtained 98 isolates of P. aeruginosa that belonged to 5 serotypes: G (n = 58), I (n = 15), C (n = 8), M (n = 5), and B (n = 2); 10 isolates were not typeable (10/98). More than 90% of the isolates formed biofilms, and 85% produced slime. All 98 isolates were resistant to 10 antibiotics (oxacillin, ampicillin, penicillin G, amoxicillin, ceftriaxone, cefazolin, cefaclor, tilmicosin, tildipirosin, and sulfonamide). However, almost all were susceptible to gentamicin, polymyxin B, and amikacin. We identified 56 unique genotypes by pulsed-field gel electrophoresis. These findings have revealed genetic diversity and high antimicrobial resistance in P. aeruginosa isolated from mink with hemorrhagic pneumonia and will facilitate the prevention and control of this disease.

Use of platelet-rich plasma for the treatment of prostatic cysts in dogs

Enrico Bigliardi, Anna Maria Cantoni, Valeria De Cesaris, Laura Denti, Virna Conti, Mara Bertocchi, Francesco Di Ianni, Enrico Parmigiani, Stefano Grolli (page 264)

Abnormalities of the canine prostate gland, in particular, benign hyperplasia and cysts, are frequent in dogs over 5 years of age. Treatment strategies for dogs with prostatic cysts include ultrasound-guided percutaneous drainage with alcohol sclerotherapy, reduction surgery, and omentalization. The aim of this study was to evaluate the use of platelet-rich plasma (PRP) for the treatment of prostatic cysts in dogs. Ten mixed breed adult male dogs were included in the study. Percutaneous drainage was performed prior to ultrasound-guided PRP injection with a 21G spinal needle. The PRP dose contained half of the solution drained from the cyst. Follow-ups were performed 6, 12, 24, and 60 d after treatment. Ten prostatic cysts were successfully treated with PRP after the ultrasound-guided drainage of the cystic cavities. No side effects were observed during the procedures. After the introduction of PRP, cysts detected by ultrasound appeared hypoechoic. On the sixth day, the hypoechoic appearance was maintained and margins were still identifiable. At 24-day and 60-day follow-ups, cysts were no longer detectable by ultrasound. One of the ten dogs had to be euthanized because of the presence of a malignant mesenchymal neoplasm of the oral cavity (fibroblastic sarcoma) and histological examination of serial sections of the prostate gland was performed. Histologic evaluation 1 year after treatment showed a regression of the cystic lesion injected with PRP. The therapy, which uses PRP injection in combination with ultrasound-guided drainage, can be considered a safe and effective strategy for the treatment of prostatic cysts in dogs.

Comparison of saphenous and cephalic blood lactate concentrations in dogs with gastric dilatation and volvulus: 45 cases

Liron D. Oron, Sigal Klainbart, Yaron Bruchim, Jantina McMurray, Søren Boysen, Matan Saar, Efrat Kelmer (page 271)

Gastric dilatation and volvulus (GDV) is a life-threatening condition, suspected to result in differential tissue perfusion in different regions of the body. Lactate is a biomarker of hypoperfusion that correlates with treatment outcomes in dogs with GDV. This prospective observational study aimed to compare lactate between saphenous and cephalic venous samples in 45 client-owned dogs with GDV, to evaluate their association with treatment outcomes (survival, surgical complications, and duration of hospitalization) and to assess the correlation between lactate and other biochemical parameters.

Both saphenous and cephalic lactate concentrations were significantly higher in non-survivors (P = 0.01). No statistical difference was found between lactate concentrations in saphenous versus cephalic venous samples (P = 0.480). For each dog, the difference in lactate between saphenous and cephalic veins was calculated (Δlactate = saphenous − cephalic); it was not associated with survival (P = 0.198), surgical complications (P = 0.346), or duration of hospitalization (P = 0.803). Higher lactate and lower glucose (saphenous vein) were associated with lower PCV and higher creatinine, on presentation.

The results of this study failed to show an association between Δlactate concentrations and treatment outcomes in dogs with GDV; however, in agreement with previous studies, lower lactate was associated with a decreased mortality rate.

Effects of immunosuppressive prednisolone therapy on pancreatic tissue and concentration of canine pancreatic lipase immunoreactivity in healthy dogs

Hiroshi Ohta, Kazuki Kojima, Nozomu Yokoyama, Noboru Sasaki, Yumiko Kagawa, Kiwamu Hanazono, Tomohito Ishizuka, Keitaro Morishita, Kensuke Nakamura, Satoshi Takagi, Mitsuyoshi Takiguchi (page 278)

The objective of this study was to examine the effects of immunosuppressive prednisolone therapy on pancreatic tissue and the concentration of serum canine pancreatic lipase immunoreactivity (cPLI) in healthy dogs. Six healthy beagle dogs were subcutaneously administered an immunosuppressive dose of prednisolone [4 mg/kg body weight (BW)] once daily for either 2 or 3 weeks. Serum cPLI concentration was measured before and after treatment. Ultrasonographic examination of the pancreas and laparoscopic biopsy and histopathological examination of the right pancreatic lobe and the liver were also conducted before and after treatment. The expression of pancreatic lipase messenger ribonucleic acid (mRNA) in the pancreas and liver was examined by polymerase chain reaction (PCR). Although the serum cPLI concentration was significantly higher on day 14 and on the day of the second laparoscopy than before treatment, it was classified as normal (≤ 200 µg/L) in 5 dogs and as abnormal (≥ 400 µg/L) in only 1 dog. None of the 6 dogs showed clinical signs of pancreatitis during the study period. After treatment, ultrasonographic examination of the pancreas showed no changes except for a hypoechoic pancreas in 1 dog. Histopathological examination of the right pancreatic lobe in all dogs showed no evidence of pancreatitis after treatment. Pancreatic lipase mRNA expression was detected in the pancreas, but not in the liver, before and after treatment. The administration of 4 mg/kg BW per day of prednisolone for 2 or 3 weeks increased the serum cPLI concentration without clinical signs of pancreatitis, although an abnormal cPLI concentration (≥ 400 µg/L) was observed in only 1 dog. No ultrasonographic or histological evidence of pancreatitis was observed in any of the dogs.

Hematological and serum biochemical profile values in pregnant and non-pregnant mares

Babak Faramarzi, Lon J. Rich, Jolan Wu (page 287)

Pregnancy in many mammals, including mares, is associated with physiological changes that are reflected in hematological and biochemical profiles. Understanding those physiological changes and differentiating them from pathological changes is imperative for providing care and medical therapy in pregnant mares. Our objective was to compare normal hematological and biochemical profiles in healthy non-pregnant as well as healthy pregnant mares during the 1st and 2nd trimesters of pregnancy. Blood was collected by jugular venipuncture into ethylenediaminetetraacetic acid and serum tubes. Whole blood was analyzed using an ADVIA 120 hematologic analyzer and serum was analyzed using a Beckman Coulter AU5400. Statistical differences were detected using analysis of variance (ANOVA) and independent Student's t-test; P < 0.05 was considered significant. Results demonstrated higher red blood cell counts and hemoglobin concentrations and lower eosinophil counts (P < 0.001) in non-pregnant mares (n = 32) compared with pregnant mares at both 1st (n = 25) and 2nd (n = 17) trimesters. Biochemical analysis showed a significant decrease (P < 0.001) in albumin and blood urea nitrogen (P < 0.001) in the 2nd trimester and higher potassium levels (P = 0.03) in pregnant mares. Understanding such physiological changes is imperative to providing optimum care and medical treatment in mares. These data will assist clinicians to better evaluate and treat pregnant mares.

The effect of graded concentrations of dietary tryptophan on canine behavior in response to the approach of a familiar or unfamiliar individual

James R. Templeman, Gary M. Davenport, John P. Cant, Vern R. Osborne, Anna-Kate Shoveller (page 294)

Tryptophan (Trp) is an indispensable dietary amino acid that supports the modulation of mood and behavior in mammalian species through its role in the serotonergic pathway. This study assessed the behavior patterns of 36 healthy, female adult mixed-breed hound dogs fed a control diet (tryptophan = 0.18% as-fed) or 1 of several experimental diets with graded concentrations of tryptophan (0.05%, 0.1%, and 0.15% of the total diet) supplemented on top of the 0.18% basal level. At baseline, and every 8 weeks throughout the 24-week period, behavioral parameters were evaluated for each dog in response to the approach of an individual familiar to the dogs and another individual who was unfamiliar to the dogs. Differences in behavior scores (activity, P = 0.0197; distance, P = 0.0358; confidence, P < 0.0001; and ear position, P < 0.0001) between the unfamiliar and familiar individuals supported the efficacy of the behavioral ethogram used. No consistent and significant differences in behavior were observed, however, among dogs fed the control diet and those fed an experimental diet with any level of tryptophan supplementation. Future research should consider the tryptophan-to-large-neutral-amino-acid ratio and not just tryptophan concentrations, seek to understand the variation in tryptophan requirements among breeds, and look to utilize additional markers of serotonin status.

Correlation between transepidermal water loss (TEWL) and severity of clinical symptoms in cats with atopic dermatitis

Marcin P. Szczepanik, Piotr M Wilkolek, Lukasz R Adamek, Grzegorz Kalisz, Marcin Golynski, Wieslaw Sitkowski, Iwona Taszkun (page 306)

The aim of this study was to demonstrate whether there is a correlation between transepidermal water loss (TEWL) and the severity of skin lesions in cats with feline atopic dermatitis (AD). The severity of symptoms was determined by using 2 scoring systems for clinically assessing the skin lesions in cats: Scoring Feline Allergic Dermatitis (SCORFAD) and Feline Extent and Severity Index (FeDESI). Such a correlation between TEWL and systems for clinically evaluating symptoms has already been shown in humans and dogs. Measurements were taken in 18 European Shorthair cats: 11 females and 7 males. Scores were calculated using SCORFAD and FeDESI and TEWL was measured in 7 areas of the body. Correlations were calculated between SCORFAD and TEWL and between FeDESI and TEWL for each body region and the average TEWL was also calculated with each system. Positive correlations were found between SCORFAD and TEWL in 3 of the examined areas: thorax (r = 0.44, P = 0.02); axilla (r = 0.39, P = 0.04); and forelimb (r = 0.55, P = 0.02). A correlation was also found between the average TEWL and SCORFAD (r = 0.41, P = 0.03). In the case of FeDESI, a correlation was found in the forelimb (r = 0.53, P = 0.02), but no correlation was found between FeDESI and the average TEWL. The results obtained showed that TEWL can be used as an additional tool in clinically assessing atopic dermatitis in cats, although it seems to be less useful in cats than in humans.

Brief Communications

A method to detect Escherichia coli carrying the colistin-resistance genes mcr-1 and mcr-2 using a single real-time polymerase chain reaction and its application to chicken cecal and porcine fecal samples

Gabhan Chalmers, Kristin E. Davis, Zvonimir Poljak, Robert Friendship, Michael R. Mulvey, Anne E. Deckert, Richard J. Reid-Smith, Patrick Boerlin (page 312)

Colistin is one of the last-resort antibiotics for the treatment of multidrug-resistant infections in humans, but transmissible colistin-resistance genes have emerged in bacteria from animals. The rapid and sensitive detection among animals of colonization with bacteria carrying these genes is critical in helping to control further spread. Here we describe a method for broth enrichment of colistin-resistant Escherichia coli from animal fecal and cecal samples followed by real-time polymerase chain reaction (PCR) for the simultaneous detection of two of the main colistin-resistance genes, mcr-1 and mcr-2. The PCR uses a single set of nondegenerative primers, and mcr variants can be differentiated by melt-curve analysis. Overnight culture enrichment was effective for amplifying colistin-resistant E. coli, even when initially present in numbers as low as 10 bacteria per gram of sample. The mcr-1 and mcr-2 genes were not found in any of the Ontario swine and poultry samples investigated.

Competitive Luminex immunoassays for detection of antibodies to foot-and-mouth disease and vesicular stomatitis viruses in multiple susceptible hosts

Charles Nfon, Diana Lusansky, Melissa Goolia, Ming Yang, Kate Hole, Leanne McIntyre (page 316)

Foot-and-mouth disease (FMD) and vesicular stomatitis (VS) cause such similar clinical signs and lesions that laboratory tests are required to distinguish between infections caused by each virus. Using mouse anti-foot-and-mouth disease virus (FMDV) 3B monoclonal or polyclonal anti-vesicular stomatitis virus-New Jersey (VSV-NJ) antibodies and recombinant FMDV 3ABC or VSV-NJ glycoprotein (G) antigens coated to MagPlex beads, competitive Luminex immunoassays (cLIAs) were developed for FMDV and VSV-NJ, respectively. The cLIAs successfully detected antibodies to FMDV 3ABC and VSV-NJ G in sera from infected animals. The diagnostic sensitivity and specificity were 93% and 98%, respectively for FMDV and 93% and 95.4%, respectively for VSV-NJ. These cLIAs are potential alternatives for competitive enzyme-linked immunosorbent assays (cELISAs) and provide the opportunity for multiplexing to reduce time and the amount of serum required for testing.