CVMA | Table of Contents and Abstracts

Table of Contents and AbstractsJuly 2021, Vol. 85, No. 3


CD34 protein is expressed in murine, canine, and porcine lungs

Gurpreet K. Aulakh, Sushmita Maltare, Le Nguyen Phuong Khanh, Baljit Singh (page 161)

The cell surface protein CD34 is expressed in various human tissues and cells, including hematopoietic stem cells, vascular endothelial cells, mucosal dendritic cells, mast cells, eosinophils, microglia, fibrocytes, muscle satellite cells, and platelets. There is a lack of data on the expression of CD34 in canine and porcine tissues. Therefore, we designed a series of immunoblotting, immunohistochemistry, and immunofluorescence experiments to observe CD34 expression in murine, canine, and porcine lungs. We used a rabbit antibody (clone EP373Y) to target the conserved human CD34 C-terminal region and validated its immunoreactivity against mouse lung homogenates. The data showed diffuse bronchiolar and alveolar epithelial localization of CD34 protein in normal murine, canine, and porcine lungs. At 9 or 24 h after bacterial endotoxin exposure, murine CD34 protein shifted to specific bronchoalveolar cells with a punctate pattern, as quantified by CD34 fluorescence. Specific porcine bronchoalveolar cells and leukocytes had significant CD34-positive immunostaining after H3N1 influenza infection. Thus, our study provides fundamental data on the expression of CD34 in lungs and validates an antibody for use in further experiments in these animal species.

Light and electron-microscopic localization of CD9 and surfactant protein A and D in normal lungs of the horse

Tara Bocking, Baljit Singh (page 170)

The lung is a complex organ, and its physiology and immunology are regulated by various immune molecules and cells. Lung surfactant, a mixture of phospholipids and proteins produced by the bronchiolar and type II alveolar epithelial cells, is one such important player in lung physiology. Compared to knowledge about the biology of the surfactant in rodents and humans, only limited data are available on the surfactant in the horse. Although there are data linking levels of surfactant proteins with respiratory disease in the horse, there are no data on the cellular localization of surfactant protein A (SP-A) and surfactant protein D (SP-D). A member of the tetraspanin family of proteins, CD9 is a cell-signaling and adhesion protein and its expression has been detected in both normal and cancer cells, including those in the lung. Because there are no immunolocalization data on SP-A, SP-D, and CD9 in the normal lungs of the horse, our objective was to conduct a light and electron microscopic immunocytochemical study on normal lungs of the horse. The data showed SP-A and SP-D in bronchiolar epithelial and type II alveolar epithelial cells. These proteins were also localized in type I alveolar epithelial cells, pulmonary intravascular macrophages, and neutrophils, which is likely an outcome of endocytosis of the proteins by these cells. CD9 was present in the airway and vascular smooth muscle cells, endothelium, and blood cells, but not in the airway epithelium. These new data provide a baseline to further examine the expression and functions of SP-A, SP-D, and CD9 proteins in inflammation associated with respiratory diseases in the horse.

Anti-obesity effects of Celastrus orbiculatus extract containing celastrol on canine adipocytes

Cho-Won Kim, Ryeo-Eun Go, Hong Kyu Lee, Byeong-Teck Kang, Woo Jae Cho, Kyung-Chul Choi (page 177)

From 50 to 60% of companion animals in the United States are overweight or obese and this obesity rate is rising. As obesity is associated with a number of health problems, an agent that can help weight loss in pets and assist in clinically managing obesity through veterinary prescription foods and medication would be beneficial. Many studies have shown that celastrol, a phytochemical compound found in Celastrus orbiculatus extract (COE), has anti-obesity and anti-inflammatory effects, although these effects have not yet been determined in canine or canine-derived cells. The objective of this study was to investigate the effects of celastrol on the adipogenic differentiation and lipolysis of canine adipocytes. Primary preadipocytes were isolated from the gluteal region of a beagle dog and the primary adipocytes were differentiated into mature adipocytes by adipocyte differentiation media containing isobutylmethylxanthine, dexamethasone, and insulin. In a water-soluble tetrazolium (WST) assay, the cell viability of mature adipocytes was decreased after treatment with COE (0, 0.93, 2.32, and 4.64 nM celastrol) in a concentration-dependent manner, although preadipocytes were not affected. Oil Red O (ORO) staining revealed that COE inhibited the differentiation into mature adipocytes and lipid accumulation in adipocytes. In addition, treatment with COE significantly reduced triglyceride content and increased lipolytic activities by 1.5-fold in canine adipocytes. Overall, it was concluded that COE may enhance anti-obesity activity in canine adipocytes by inhibiting lipid accumulation and increasing lipolytic activity.

Evaluation of reproductive traits and ovarian and uterine morphology of sows with different genotypes for the estrogen receptor, prolactin receptor, and follicle-stimulating hormone subunit beta genes

Alena Yurina, Evgeny Skovorodin, Irina Dolmatova (page 186)

The purpose of this study was to analyze the morpho-functional features of the ovaries and uterus of sows with different genotypes for the estrogen receptor (ESR), prolactin receptor (PRLR), and follicle-stimulating hormone subunit beta (FSHβ) genes associated with reproductive traits. Healthy Large White sows were studied. The genotypic status of the ESR, PRLR, and FSHβ genes was detected by polymerase chain reaction-restriction fragment length polymorphism. The structure of the ovaries and uterus was studied using quantitative assessment of organs and histological research. Sows with the ESRBB genotype significantly exceeded animals with the ESRAA genotype in milk yield (by 0.3 kg) and in the number of piglets at birth (by 0.9 animals) and at weaning (by 0.7 animals).

Sows with the ESRAB genotype were midway between those with ESRBB and ESRAA genotypes in terms of these reproductive traits. Animals with the PRLRAA genotype significantly exceeded those with the PRLRBB genotype in the number of piglets born (P < 0.05); the differences in litter weight at birth were not significant. Compared to other genotypes, sows with genotypes ESRBB (P < 0.05) and PRLRAA (AB) (P < 0.05) had larger uteruses and more yellow bodies, tertiary follicles, and primordial follicles in their ovaries. Animals with the FSHβBB genotype significantly exceeded animals with the FSHβAB genotype in the length of uterus by 21 cm (P < 0.05).

Effect of anesthesia duration on the quality of recovery in horses undergoing elective and emergency surgeries using the same anesthetic protocol

Hanna Vermedal, Alexander Valverde, William Sears (page 193)

The objective of this study was to investigate the effect of anesthesia duration on the quality of recovery in horses. The medical records of horses that were anesthetized and underwent surgery for elective and emergency soft tissue and orthopedic conditions from 2013 to 2019 were reviewed. Horses included in the study (N = 305) fulfilled the following requirements: all had the same premedication/induction protocol and the same balanced anesthesia for maintenance and were anesthetized by the same, experienced Board-certified anesthesiologist. A standardized anesthetic recovery score was completed for all horses to evaluate their recovery and the following interactions were assessed: age, body weight, breed, sex, American Society of Anesthesiologists status, type of surgical procedure, occurrence of hypotension, use of dobutamine, number of additional doses of xylazine/ketamine after isoflurane discontinuation, anesthesia duration, post-anesthetic sedation, and end-tidal isoflurane concentration during maintenance and at the time of transfer to the recovery room. These interactions were assessed based on the quality of recovery score using logistic regression. Duration of anesthesia (P = 0.021) and age (P = 0.003) negatively affected the quality of recovery. The odds of a worse recovery score were increased by 1.20-fold (1.03, 1.41; lower and upper limits) for every additional 30 min of anesthesia duration, while the odds of a worse recovery score were increased by 1.09-fold (1.03, 1.16) for every additional 1 y of age. In conclusion, the results of this retrospective study indicate that increasing the anesthesia duration negatively affects the quality of recovery in horses undergoing routine and emergency surgical procedures.

Topical N-palmitoyl serinol, a commensal bacterial metabolite, prevents the development of epidermal permeability barrier dysfunction in a murine model of atopic dermatitis-like skin

Si Wen, Li Ye, Dan Liu, Bin Yang, Mao-Qiang Man (page 201)

Recent studies have demonstrated that commensal bacterial metabolites benefit human health. Because of the crucial role of the epidermal permeability barrier in cutaneous and extracutaneous function, we assessed whether the topical applications of N-palmitoyl serinol (NPS) would improve the epidermal permeability barrier in murine skin. Our results show that the topical application of 0.5% NPS in ethanol twice daily for 1 week lowered basal transepidermal water loss rates and accelerated barrier recovery in normal mice. Moreover, topical NPS prevented the emergence of epidermal permeability barrier dysfunction in a murine model of allergic contact dermatitis. These results suggest that topical NPS could be used to prevent or treat skin disorders characterized by inflammation and an abnormal epidermal permeability barrier.

The accuracy of tactile assessment of canine nose temperature to identify rectal hyperthermia and hypothermia in dogs presenting on an emergency basis

Christopher R. Kennedy, Jonathan M. Babyak, Elizabeth A. Rozanski (page 205)

The goals of this study were to evaluate whether touch can identify a warm nose as opposed to a cold nose, to examine the correlation between thermographically measured nose temperatures and rectal temperatures, and to calculate the accuracy of tactile assessment of nose temperature in detecting rectal hyperthermia and hypothermia in dogs. A total of 100 dogs presenting to an emergency room was prospectively enrolled. Tactile nose assessment was carried out on triage. Noses were subjectively categorized as warm, cold, or intermediate (neither warm nor cold). Thermographic nose temperatures were recorded using a thermal imaging camera. Tactile assessment categorized noses as warm, intermediate, or cold (P < 0.01). There was no correlation between thermographically measured nose temperature and rectal temperature (r = 0.02). Tactile assessment of noses as warm had a sensitivity of 29.4% and a specificity of 79.5% for detecting rectal hyperthermia; calculated test accuracy was 71%. Tactile assessment of noses as cold had a sensitivity of 54.5% and a specificity of 62.9%; calculated test accuracy was 62%. It was concluded that nose temperatures do not correlate with rectal temperatures. Tactile assessment of nose temperature is inaccurate for identifying rectal hyperthermia or hypothermia.

The effect of an energy additive on the metabolism of cattle

Elina Nafikova, Irina Mironova, Igor Gazeev, Dmitry Blagov, Azat Nigmatiyanov (page 210)

The objective of this study was to determine the effect of an energy additive on the metabolism of cattle. This article provides information on the analysis of the diet of young cattle calculated for when the animals were both indoors and outdoors. The ration was prepared for 40 heifers, divided into 4 groups consisting of 10 animals in each group. Three of these groups were fed different amounts of a high-energy additive, which was not fed to the control group. The effectiveness of the additive was analyzed according to the balance experiment and by calculating digestibility coefficients. It was determined that the percentage of nitrogen use in young animals was higher in the groups that were fed the additive than in the control group. Increasing the dose of the additive increased the level of nitrogen use. Comparative analysis of live weight indicated intergroup differences in favor of heifers in the groups that were fed the additive of 1.34% to 2.41% at the age of 9 mo; 2.51% to 4.16% at 12 mo; 3.14% to 5.46% at 15 mo; and 3.57% to 6.30% at 18 mo. The average daily growth dynamics indicated a gradual increase in all animals up to 15 mo, with a slight decrease by 18 mo of age. The difference among the groups ranged from 5.08% to 8.85% at 6 to 9 mo of age; 7.08% to 10.79% at 9 to 12 mo; 5.64% to 10.97% at 12 to 15 mo; and 6.05% to 11.11% at 18 mo. It was concluded that feeding the energy additive Tanrem to heifers increased their metabolism so that nitrogen use was improved, and feed was digested more efficiently, which in turn improved the growth of animals. Using an energy additive at the mid-range dose of 500 g a day per animal is recommended, since the effect was similar at the mid-range and maximum dosages.

Brief Communications

Whole genome sequencing of methicillin-resistant and methicillin-sensitive Staphylococcus aureus isolated from 4 horses in a veterinary teaching hospital and its ambulatory service

Paloma Morice, Marion Allano, Chantale Provost, Julie-Hélène Fairbrother, Carl A. Gagnon, Frédéric Sauvé (page 218)

Genomic characterization was conducted on 2 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from 2 horses hospitalized during an overlapping period of time and 2 methicillin-sensitive S. aureus (MSSA) strains isolated from 2 distinct horses. Phylogenetic proximity was traced and the genotypic and phenotypic characteristics of the antimicrobial resistance of the strains were compared.

Whole genome sequencing of MRSA strains for this report was similar but differed from whole genome sequencing of MSSA strains. The MRSA strains were closely related, belonging to sequence type (ST) 612, spa type t1257, and SCCmec type IVd2B. The MSSA strains were also closely related, belonging to ST1660, spa type t3043, and having no detectable staphylococcal cassette chromosome mec elements. All MSRA and MSSA strains were Panton-Valentine leukocidin negative. There were discrepancies in the genotypic analysis and the antimicrobial susceptibility testing (phenotypic analysis) of MRSA strains for rifampin, trimethoprim-sulfamethoxazole, gentamicin, amikacin, and enrofloxacin.

Emergence of a novel recombinant USA/GBI29/2015-like strain of Seneca Valley virus in Guangdong Province, 2018

Jianguo Dong, Dan Rao, Shuhai He, Fengchao Jiao, Benchi Yi, Bin Chen, Chaoliang Leng, Li Huang (page 224)

Since June 2017, several outbreaks of a Seneca Valley virus (SVV) USA/GBI29/2015-like strain have emerged in pigs in China. In our study, we successfully isolated the SVV strain CH-GDZQ-2018, confirmed by immunofluorescence and Western blot assays. Phylogenetic and recombinant analyses showed that the USA/GBI29/2015-like CH-GDZQ-2018 strain was the result of recombination between epidemic strains local to Guangdong, showing that SVV has undergone evolution in China.

Beekeeping management practices in southwestern Quebec

Gabrielle Claing, Pascal Dubreuil, Julie Ferland, Martine Bernier, Julie Arsenault (page 229)

The growing number of honey bee colonies and beekeepers in Canada has led to a great diversity of beekeeping practices. All beekeeping operations, however, need to implement consistent management measures for the control of diseases. The objective of this study was to document the actual disease management practices of beekeeping productions in southwestern Quebec, Canada. A survey was conducted to describe management practices used by 15 beekeepers who own 1824 colonies in that area. Data were obtained by telephone interviews. When infectious diseases were suspected, beekeepers generally avoided using potentially toxic acaricides and chemical treatments associated with antimicrobial resistance and instead used preventive, physical or management methods, although laboratory diagnosis was rarely used. This study highlights the wide variety of operation sizes, activities, and disease management strategies among beekeepers in southwestern Quebec. It identifies the need to encourage the use of services available to them and to propose a standardized preventive medical approach for field veterinarians to avoid the spread of infectious diseases.

Establishment of a canine lens epithelial cell line

Akira Matsuda, Yuki Shimizu, Teppei Kanda, Akihiro Ohnishi, Noritaka Maeta, Masahiro Miyabe, Kaori Saeki, Yoshiki Itoh (page 236)

Some immortalized lens epithelial cell lines have been established and are useful for molecular analysis. The establishment of additional cell lines must, however, enable a variety of in-vitro examinations. The objective of this study was to establish a new canine lens epithelial cell line by isolating CLC-1 cells from the lens tissue of a dog with cataracts. In CLC-1 cells, transforming growth factor beta (TGF-β) treatment significantly decreased gene expression of an epithelial marker and elevated that of mesenchymal markers; these characteristics are similar to those of a human lens epithelial cell line. Interestingly, CLC-1 cells exhibited lower expression of an epithelial marker and higher expression of mesenchymal markers than an anterior lens capsule. These results suggest that CLC-1 cells were derived from a cell population that was committed to epithelial-mesenchymal transition in cataract lens tissue. In conclusion, CLC-1 cells could be useful for analyzing molecular pathogenesis in canine cataracts.