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Phylogenetic analysis of a partial L1 gene from bovine papillomavirus type 1 isolated from naturally occurring papilloma cases in the northwestern region of Turkey
2017
Timurkan, M. Ozkan(Atatürk University Department of Virology) | Alcigir, M. Eray(Ankara University Department of Pathology)
This study was aimed at the molecular characterisation of bovine papillomavirus type 1 (BPV-1) isolated from papilloma cases in the northwestern region of Turkey. BPV-1 is a widely occurring oncogenic virus in cattle and is associated with benign epithelial neoplasia which causes significant economic losses in dairy and beef cattle because of treatment costs. In this study, 29 suspected papilloma specimens were collected from cattle in northwestern Turkey. These samples underwent molecular characterisation via the polymerase chain reaction (PCR) and sequencing analysis as well as macroscopic and histopathological examination. The histopathological examinations confirmed papilloma as the main lesion type in the specimens. Of the 29 papilloma-like tissue samples that were collected, 11 (i.e. 37.93%) were detected as positive and determined as containing BPV-1 (11 of 11, 100%). Using a partial sequence for the L1 gene acquired from GenBank, phylogenetic analysis confirmed the presence of BPV-1 and revealed that the infection might have originated in cross bred domestic and imported cattle. This study provides potentially useful information on the origin and spread of this disease. Its results can potentially aid in the development of appropriate control measures and therapeutic or vaccination strategies against the BPV-1 strain of bovine papillomatosis.
显示更多 [+] 显示较少 [-]Geigerin-induced cytotoxicity in a murine myoblast cell line (C2C12)
2017
Botha, Christo J.(University of Pretoria Department of Paraclinical Sciences) | Clift, Sarah J.(University of Pretoria Department of Paraclinical Sciences) | Ferreira, Gezina C.H.(University of Pretoria Department of Paraclinical Sciences) | Masango, Mxolisi G.(Agricultural Research Council-Onderstepoort Veterinary Institute Food, Feed and Veterinary Public Health)
Geigeria poisoning in sheep, locally known as 'vermeersiekte', is an economically important plant poisoning in southern Africa. The toxic principles contained by the toxic plants are believed to be several sesquiterpene lactones, such as geigerin, vermeeric acid and vermeerin, which cause striated muscle lesions in small stock. Because of ethical issues surrounding the use of live animals in toxicity studies, there is currently a dire need to establish an in vitro model that can be used to replace traditional animal experimentation. The objective of this study was to determine the cytotoxicity of geigerin in a murine myoblast cell line (C2C12) using methyl-thiazol-tetrazolium (MTT) and lactate dehydrogenase (LDH) assays, annexin V and propidium iodide (PI) flow cytometry and transmission electron microscopy (TEM). Mouse myoblasts were exposed to 2.0 mM, 2.5 mM and 5.0 mM geigerin for 24, 48 and 72 h. A concentration-dependent cytotoxic response was observed. Apoptosis was detected by means of annexin V flow cytometry during the first 24 h and apoptotic bodies were also visible on TEM. According to the LDH and PI flow cytometry results, myoblast cell membranes were not injured. We concluded that the murine myoblast cell line (C2C12) is a suitable model for future studies planned to evaluate the cytotoxicity of other and combinations of sesquiterpene lactones, with and without metabolic activation, implicated in 'vermeersiekte' and to elucidate the subcellular effects of these myotoxins on cultured myoblasts.
显示更多 [+] 显示较少 [-]Somatic cell count thresholds in composite and quarter milk samples as indicator of bovine intramammary infection status
2017
Petzer, Inge-Marié(University of Pretoria Department of Production Animal Studies) | Karzis, Joanne(University of Pretoria Department of Production Animal Studies) | Donkin, Edward F.(University of Pretoria Department of Animal and Wildlife Sciences) | Webb, Edward C.(University of Pretoria Department of Animal and Wildlife Sciences) | Etter, Eric M.C.(University of Pretoria Department of Production Animal Studies ,French Agricultural Research Centre for International Development Department Environment and Societies)
The objective of the study was to establish an operational somatic cell count (SCC) threshold to predict the presence of intramammary infection (IMI) in composite milk samples and compare findings with those in quarter milk samples. South African dairy producers now preferred composite milk samples for herd udder health analysis because of increasing cow numbers, convenience of sampling and lower cost. A retrospective study was conducted on 345 461 composite and 89 638 quarter milk samples from South African herds. Variance estimates for the proportion of quarter samples testing positive were adjusted to account for the lack of their independence within individual cows. The IMI at SCC thresholds of 150 000 cells/mL and 200 000 cells/mL differed only by 3.26% in composite milk samples. Youden's index indicated the optimum SCC thresholds for composite and quarter milk samples as 150 000 cells/mL and 200 000 cells/mL, respectively. At 150 000 cells/mL, sensitivity (95% confidence intervals [CI]) in composite milk samples was 65.3% (64.0%, 66.6%) and specificity was 66.8% (65.7%, 67.9%); and in quarter milk samples, sensitivity at 200 000 cells/mL was 70.8% (69.5%, 72.0%) and specificity was 63.6% (62.4%, 64.8%). The likelihood of infection for udders and quarters, respectively, was 1.034 and 1.327 at an SCC threshold of 150 000 cells/mL and 0.864 cells/mL and 1.177 cells/mL at 200 000 cells/mL. The area under the curve of the receiver operating characteristics graph was 0.7084 and 0.7277 for composite and quarter samples, respectively, indicating that the SCC test could be considered as a good indicator of IMI in both sample types.
显示更多 [+] 显示较少 [-]Oxidative stress and food supplementation with antioxidants in therapy dogs
2017
Sechi, S. | Fiore, F. | Chiavolelli, F. | Dimauro, C. | Nudda, A. | Cocco, R.
The objective of this study was to evaluate the ability of a long-term antioxidant-supplemented diet to regulate the oxidative stress and general health status of dogs involved in animal-assisted intervention (AAI) programs. Oxidative stress is a consequence of the accumulation of reactive oxygen species (ROS). Exercise-induced oxidative stress can increase muscle fatigue and fiber damage and eventually leads to impairment of the immune system. A randomized, placebo-controlled, crossover clinical evaluation was conducted with 11 healthy therapy dogs: 6 females and 5 males of different breeds and with a mean age of 2.7 ± 0.8 y (mean ± SEM). The dogs were divided into 2 groups, 1 fed a high quality commercial diet without antioxidants (CD) and the other a high quality commercial diet supplemented with antioxidants (SD) for 18 wk. After the first 18 wk, metabolic parameters, reactive oxygen metabolite-derivatives (d-ROMs), and biological antioxidant potential (BAP) levels were monitored and showed a significant reduction of d-ROMs, triglycerides, and creatinine values in the SD group (P < 0.05) and a significant increase in amylase values in the CD group (P < 0.01). At the end of this period, groups were crossed over and fed for another 18 wk. A significant decrease in amylase and glutamate pyruvate transaminase (GPT) values was observed in the CD and SD group, respectively (P < 0.05). In conclusion, a controlled, balanced antioxidant diet may be a valid approach to restoring good cell metabolism and neutralizing excess free radicals in therapy dogs.
显示更多 [+] 显示较少 [-]Evaluation of gastric emptying time, gastrointestinal transit time, sedation score, and nausea score associated with intravenous constant rate infusion of lidocaine hydrochloride in clinically normal dogs
2017
Johnson, Rebecca A. | Kierski, Katharine R. | Jones, B. G.
OBJECTIVE To quantify nausea and sedation scores, gastric emptying time, and gastrointestinal transit time after IV administration of a lidocaine hydrochloride bolus followed by a constant rate infusion (CRI) in clinically normal dogs. ANIMALS 6 Beagles. PROCEDURES In a crossover study, dogs were fed thirty 1.5-mm barium-impregnated spheres (BIPS) and received a saline (0.9% NaCl) solution bolus (0.05 mL/kg) IV (time 0) followed by a CRI at 10 mL/h, a lidocaine bolus (1 mg/kg) IV followed by a CRI at 25 μg/kg/min, or a lidocaine bolus (1 mg/kg) IV followed by a CRI at 50 μg/kg/min; CRIs were for 12 hours. Nausea and sedation scores were assessed and abdominal radiographs obtained immediately after feeding of BIPS and every hour for 12 hours and again 16 hours after CRI start. Percentage of BIPSs in the small and large intestines, gastric emptying time, and gastrointestinal transit time were assessed. RESULTS Gastric emptying time did not differ significantly among treatments. Significantly more BIPS were in the large intestine 4 to 7 hours after treatment start for the 50-μg/kg/min treatment than for the other 2 treatments. Six hours after treatment start, significantly more BIPS were in the large intestine for the 25-μg/kg/min treatment than for the saline solution treatment. Higher sedation and nausea scores were associated with the 50-μg/kg/min CRI. CONCLUSIONS AND CLINICAL RELEVANCE In clinically normal dogs, lidocaine CRI did not significantly affect gastric emptying. However, gastrointestinal transit time was mildly decreased and sedation and nausea scores increased in dogs administered a lidocaine CRI at clinically used doses.
显示更多 [+] 显示较少 [-]Evaluation of the effects of a 4.7-mg deslorelin acetate implant on egg laying in cockatiels (Nymphicus hollandicus)
2017
Summa, Noemie M. | Sanchez-Migallon Guzman, David | Wils-Plotz, Emma L. | Riedl, Nerisa E. | Kass, Philip H. | Hawkins, Michelle G.
OBJECTIVE To evaluate effects of administration of a 4.7-mg deslorelin acetate implant on egg laying in healthy cockatiels (Nymphicus hollandicus). ANIMALS 52 cockatiels. PROCEDURES 26 breeding pairs (a female and its respective male in each pair) were selected on the basis of their history of egg laying. Female birds were sedated and received a 4.7-mg deslorelin acetate implant (n = 13) or placebo implant (13) in the subcutaneous tissues between the scapulae. Male and female birds of each breeding pair were placed in separate but adjacent cages. Birds were exposed to 16 hours of light and 8 hours of darkness. A nest box was placed in cages of female birds to stimulate reproductive activity. Egg production and quality were monitored daily for 365 days. RESULTS Deslorelin acetate implants significantly suppressed egg laying in cockatiels, compared with effects for the placebo implants. Eleven of 13 placeboimplanted birds laid eggs between 12 and 42 days after implantation. None of the deslorelin-implanted birds laid eggs within 180 days after implantation, and only 5 of 13 deslorelin-implanted birds laid an egg during the study period (first egg laid between 192 and 230 days after implantation). No differences in egg quality or number of eggs per clutch were observed between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Insertion of a 4.7-mg deslorelin acetate implant suppressed egg laying in healthy cockatiels for at least 180 days. Studies are necessary to evaluate effects of a deslorelin acetate implant in other avian species or in association with reproductive disorders.
显示更多 [+] 显示较少 [-]Assessment of regional left ventricular systolic function by strain imaging echocardiography in phenotypically normal and abnormal Maine coon cats tested for the A31P mutation in the MYBPC3 gene
2017
Pellegrino, Arine | Daniel, Alexandre G. T. | Pereira, Gulherme G. | Itikawa, Paula H. | Larsson, Maria Helena M. A.
Myocardial dysfunction occurs in cats with hypertrophic cardiomyopathy (HCM), but little is known about the early stages of the disease. Strain imaging echocardiography is a method that enables the quantitative assessment of myocardial function and deformity, allowing the characterization of systolic dysfunction. The objective of this study was to assess systolic function using strain imaging echocardiography in Maine coon cats genetically tested for the A31P mutation in the MYBPC3 gene, with and without ventricular hypertrophy. For this purpose, 57 Maine coon cats of both genders, with an unknown status regarding the mutation at inclusion, were included prospectively and evaluated by conventional and strain imaging echocardiography. Comparisons were made among cats without hypertrophy (n = 45), suspect cats (n = 7), and cats with hypertrophic cardiomyopathy (n = 5), and also between the heterozygous for the mutation group (n = 26) and the negative for the mutation group (n = 28). Finally, in the group of phenotypically normal cats, heterozygous cats carrying the mutation were compared to cats without the mutation. Strain values were compared among the groups (blinded prospective study). While echocardiography demonstrated normal contractility, strain values (middle of the septum) were lower in HCM cats. Strain values (base of anterior wall of the left ventricle) were lower in heterozygous than in negative cats, even before hypertrophy. Negative correlation was observed between some values of myocardial strain and thickness. While strain imaging echocardiography was able to detect systolic abnormalities, despite apparent normality on conventional echocardiography, it was not able to identify cats that carry the A31P mutation in the MYBPC3 gene. Strain imaging echocardiography could be a useful tool, however, for detecting systolic alterations in HCM cats with an apparently normal systolic function or for detecting alterations in normal carriers of the MYBPC3 gene mutation.
显示更多 [+] 显示较少 [-]Texture analysis of magnetic resonance images to predict histologic grade of meningiomas in dogs
2017
Banzato, Tommaso | Bernardini, Marco | Cherubini, Giunio B. | Zotti, Alessandro
OBJECTIVE To predict histologic grade of meningiomas in dogs via texture analysis (TA) of MRI scans of the brain and spinal cord. SAMPLE 58 sets of MRI scans of the brain and spinal cord of dogs with histologically diagnosed meningioma. PROCEDURES MRI sequences were divided into a training set and a test set, and results of histologic assessment were obtained. Tumors were histologically grouped as benign (stage I) or atypical-anaplastic (stage II or III). Texture analysis was performed by use of specialized software on T2-weighted (T2W) and pre- and postcontrast T1-weighted (T1W) images. A set of 30 texture features that provided the highest discriminating power between the 2 histologic classes in the training set was automatically selected by the TA software. Linear discriminant analysis was performed, and the most discriminant factor (MDF) was calculated. The previously selected texture features were then used for linear discriminant analysis of the test set data, and the MDF was calculated. RESULTS For the training set, TA of precontrast T1W images provided the best diagnostic accuracy; a cutoff MDF of < 0.0057 resulted in a sensitivity of 97.4% and specificity of 95.0% for discriminating benign from atypical-anaplastic meningiomas. Use of postcontrast T1W and T2W images yielded poorer diagnostic performances. Application of the MDF cutoff calculated with the training set to the MDF calculated with the test set provided a correct classification rate of 96.8% for precontrast T1W images, 92.0% for postcontrast T1W images, and 78.9% for T2W images. CONCLUSIONS AND CLINICAL RELEVANCE Findings supported the potential clinical usefulness of TA of MRI scans for the grading of meningiomas in dogs.
显示更多 [+] 显示较少 [-]Phylogenetic analysis of Escherichia coli isolated from broilers with colibacillosis based on gyrA gene sequences
2017
Shamsi, H. | Mardani, K. | Ownagh, A.
Escherichia coli isolates from chickens with colibacillosis were assigned to phylogenetic groups based on multiplex polymerase chain reaction (PCR) and antibacterial resistance of E. coli belonging to these groups was examined. Furthermore, the gyrA gene of isolates was sequenced and a phylogenetic tree was generated. A total of 84 E. coli isolates were grouped using multiplex PCR of TSPE4.C2, chuA, yjaA, and gadA molecular markers. Four phylogenetic groups were identified with strains divided as follows: 16 in group A (19.05%), 17 in group B1 (20.24%), 23 in group B2 (27.38%), and 28 in group D (33.33%). Escherichia coli isolates belonging to phylogenetic groups B2 and D were resistant to Soltrim and Flumequine unlike the majority of E. coli isolates that belonged to groups A and B1, and which were susceptible to these antibiotics. The phylogenetic results based on gyrA gene sequences from multiplex PCR revealed that E. coli phylogenetic grouping was in accordance with the clusters obtained in the phylogenetic tree. In conclusion, the comparative sequence analysis of gyrA sequences provides a firm framework for an accurate classification of E. coli and related taxa and may constitute a pertinent phylogenetic marker for E. coli.
显示更多 [+] 显示较少 [-]Maternal and fetal effects of dexmedetomidine infusion in pregnant ewes anesthetized with sevoflurane
2017
Lepiz, Mauricio Loria | Sayre, Rebecca | Sawant, Onkar | Barr, James | Pashmakova, Medora | Washburn, K. (Kevin) | Washburn, Shannon
OBJECTIVE To characterize the maternal and fetal cardiopulmonary effects of a low-dose infusion of dexmedetomidine without a loading dose in pregnant ewes anesthetized with sevoflurane. ANIMALS 11 pregnant ewes. PROCEDURES Anesthesia was induced with propofol and maintained with sevoflurane. Ewes and fetuses were instrumented with arterial and venous catheters, and thermodilution–pulmonary arterial catheters were placed in the ewes. Baseline measurements were obtained at an end-tidal sevoflurane concentration of 3.4%, then dexmedetomidine (2 μg/kg/h, IV) was infused for 90 minutes without a loading dose. Cardiovascular and blood gas variables were measured at predetermined time points. RESULTS Dexmedetomidine infusion resulted in approximately 30% decreases in maternal systemic vascular resistance, blood pressure, and heart rate. Maternal cardiac index, oxygenation variables, and acid-base status remained unchanged, whereas pulmonary arterial pressure, pulmonary vascular resistance, and stroke volume increased, compared with baseline values. Uterine blood flow decreased by approximately 30% to 36%. Fetal heart rate and blood pressure remained unchanged, but significant increases in fetal plasma glucose and lactate concentrations were detected. CONCLUSIONS AND CLINICAL RELEVANCE Pregnant ewes receiving a combination of sevoflurane and an infusion of dexmedetomidine without a loading dose had cardiac index in acceptable ranges and maintained normoxia. This balanced anesthesia did not produce significant changes in fetal blood pressure or heart rate. However, the increase in fetal plasma lactate concentration and changes in maternal pulmonary vascular resistance and uterine blood flow require further investigation to better elucidate these effects.
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