Canadian journal of veterinary research = Revue canadienne de recherche veterinaire最新文献

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 ESR ^BB genotype significantly exceeded animals with the ESR ^AA 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 ESR ^AB genotype were midway between those with ESR ^BB and ESR ^AA genotypes in terms of these reproductive traits. Animals with the PRLR ^AA genotype significantly exceeded those with the PRLR ^BB 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 ESR ^BB (P < 0.05) and PRLR ^{AA (AB)} (P < 0.05) had larger uteruses and more yellow bodies, tertiary follicles, and primordial follicles in their ovaries. Animals with the FSHβ ^BB genotype significantly exceeded animals with the FSHβ ^AB genotype in the length of uterus by 21 cm (P < 0.05).

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.

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.

The effects of head position on internal carotid artery (ICA) and external carotid artery (ECA) pressures in standing sedated horses were evaluated in this study. The common carotid artery (CCA) was catheterized in 6 horses using an ultrasound-guided technique to facilitate placement of a pressure transducer within the ICA and ECA at the level of the guttural pouch. Transducer position was confirmed by endoscopic visualization. Mean arterial pressure (MAP) was measured with horses in both a head-up and head-down position. The dorsal metatarsal artery was catheterized as a control. Maintaining a head-up position decreased MAP in both the ICA (median: 75.21 mmHg) and ECA (median: 79.43 mmHg), relative to the head-down position (ICA median: 104.65 mmHg; ECA median: 102.26 mmHg). Mean arterial pressure in the dorsal metatarsal artery was not affected by head position. The head-up position resulted in lower arterial pressures in both the ICA and ECA (P = 0.03) compared with the head-down position in standing sedated horses.

Decreased neutrophil function following administration of chemotherapy has been reported in dogs with lymphoma. The first objective of our study was to determine if neutrophil oxidative burst and phagocytic activity are affected by chemotherapy 7 to 10 days following initiation of treatment in dogs with lymphoma and non-lymphoma malignancies. The second objective was to determine if there is a correlation between neutrophil numbers and neutrophil function before or after initiation of chemotherapy. Flow cytometric assessment of neutrophil oxidative burst and phagocytosis following stimulation with Escherichia coli was performed in 9 dogs diagnosed with lymphoma and 17 non-lymphoma tumor-bearing dogs pre- and post-chemotherapy, as well as 14 tumor-free control dogs. Spearman rank correlation was performed to determine if blood neutrophil numbers and neutrophil function were significantly correlated. Lymphoma patients showed significantly reduced percentage neutrophil oxidative burst post-chemotherapy compared to healthy controls as well as compared to pre-chemotherapy values (P = 0.0022 and P = 0.0020, respectively). Lymphoma patients also exhibited significantly reduced neutrophil phagocytosis activity post-chemotherapy compared to controls and pre-chemotherapy values (P = 0.0016 and P = 0.014, respectively). Dogs with non-lymphoma malignancies also showed a significant decrease in both percentage oxidative burst and phagocytosis post-chemotherapy compared to pre-chemotherapy values (P = 0.00040 and P = 0.029, respectively). Neutrophil numbers and function were not significantly correlated. The results of the study suggest that chemotherapeutic treatment decreases neutrophil oxidative burst and phagocytic activity 7 to 10 days post-treatment in dogs with various malignancies. Furthermore, neutrophil numbers cannot be used to predict neutrophil function.

The popularity and availability of echocardiography in veterinary practice for companion animals have substantially increased in recent years. The results obtained during the procedure are compared to reference values established for the general dog population or to standards developed for a specific dog breed. The aim of this study was to determine whether individual dog traits, such as body weight, chest structure, and level of physical activity and performance, affect the reference values for echocardiographic parameters. Published reference values for echocardiographic examination parameters for 32 dog breeds were analyzed and the relationship between individual echocardiographic parameters and body weight, chest structure, and level of physical activity and performance was then statistically analyzed. It was found that echocardiographic parameters are affected by the dog's weight and physical activity. There was no significant relationship between heart size and chest structure. The great variety of dog breeds means that echocardiographic findings should be individually interpreted rather than establishing reference ranges for each breed in population studies. This will allow for a more accurate interpretation of the results obtained in the echocardiographic examination and consequently lead to earlier diagnosis of changes in myocardial morphology.

Disinfection is key for controlling microbial contamination and ensuring the safe production of milk and dairy products. In this study, we developed a new disinfection method using quaternary ammonium surfactant N-dodecyl-2-(pyridin-1-yl) acetamide chloride as the main component to form a bactericidal complex with either chlorhexidine acetate or glutaraldehyde, and we evaluated the bactericidal effects, safety, and clinical application value of the compound disinfectants. An in vivo acute oral toxicity assay in mice showed an LD₅₀ > 5000 mg/kg body weight without abnormality in pathological tissue sections. Comparison with commercially available products also showed that they have outstanding bactericidal effects. Clinical trials proved that the compound disinfectants have excellent bactericidal effects on the air and ground of the dairy farm and on the skin of cattle, especially in a dairy farm environment. Our findings confirm that the new compound disinfectants have excellent bactericidal performance and are safe to use as disinfectants to prevent mastitis and contamination of the cattle farm environment.

Urinary liver-type fatty acid-binding protein (uL-FABP) is a clinically useful biomarker for monitoring chronic kidney disease (CKD) in humans. However, long-term monitoring of uL-FABP in CKD cats has not been reported. The objective of this preliminary study was to investigate whether the urinary excretion of L-FABP could predict the deterioration of renal function in 2 CKD model cats. Urinary liver-type fatty acid-binding protein (uL-FABP) increased before standard renal biomarkers, including serum creatinine, blood urea nitrogen, and symmetric dimethylarginine, in 1 cat with deteriorating renal function, but remained low and relatively stable in another cat with stable renal function. Our results suggest that uL-FABP is a potential clinical biomarker for predicting the progression of CKD in cats, as it is in humans.

The purpose of this retrospective analysis was to determine if fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) could potentially be an accurate staging tool for detecting metastatic lymph nodes in dogs with appendicular osteosarcoma based on the quantitative measurement of the maximum standard uptake value (SUV_max) of lymph nodes. A total of 53 dogs were identified that presented for staging via ¹⁸F-FDG PET/CT for primary appendicular osteosarcoma. Patients were categorized according to lymph node status of having either metastatic or non-metastatic nodes based on cytological or histological analysis. Maximum standard uptake (SUV_max) values of the sampled lymph node(s) were recorded and 3/77 (3.9%) of sampled lymph nodes were confirmed metastatic. A Mann-Whitney test revealed a statistical difference in the SUV_max of the metastatic versus non-metastatic lymph nodes [median: 6.6 to 95% confidence interval (CI): 2.56 to 14.37 versus 2.18 95% CI: 2.32 to 3.17, respectively, P-value = 0.05]. This retrospective analysis revealed a significant difference in the SUV_max as measured on ¹⁸F-FDG PET/CT between metastatic lymph nodes and non-metastatic lymph nodes in canine patients afflicted with appendicular osteosarcoma, in spite of the small numbers analyzed. While these results are promising, they should be interpreted with caution and further studies are justified.

In humans and other mammals, general anesthesia impairs thermoregulation, leading to warm core blood redistributing to the periphery. This redistribution is an important contributor to hypothermia that can be reduced with pre-warming before anesthesia. Additionally, sedation following premedication has been associated with hypothermia in dogs. In a prospective, randomized, cross-over study, 8 adult male and female rats (weighing 388 to 755 g) were sedated with intramuscular ketamine-midazolam-hydromorphone, then placed in an unwarmed cage or warmed box for 14 minutes, followed by 30 minutes of isoflurane anesthesia with active warming. Core body temperature was monitored throughout. After sedation, warmed rats gained 0.28°C ± 0.13°C and unwarmed rats lost 0.19°C ± 0.43°C, a significant difference between groups (P = 0.004). After anesthesia, warmed rats maintained higher core temperatures (P < 0.0001) with 2/8 and 6/8 of warmed and unwarmed rats becoming hypothermic, respectively. Pre-warming during sedation and active warming during general anesthesia is effective in minimizing hypothermia.