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Immunogenicity of a plasmid DNA vaccine encoding G1 epitope of bovine ephemeral fever virus G glycoprotein in mice
2018
Pasandideh, Reza(Natural Resources University Department of Animal Science, Khuzestan Agricultural Sciences) | Shapouri, Masoud Reza Seyfi Abad(Shahid Chamran University of Ahvaz Department of Pathobiology) | Nassiri, Mohammad Taghi Beigi(Natural Resources University Department of Animal Science, Khuzestan Agricultural Sciences)
The aim of this study was to investigate the immunogenicity of a plasmid deoxyribonucleic acid (DNA) vaccine encoding the G1 epitope of bovine ephemeral fever virus (BEFV) G glycoprotein in mice. A plasmid DNA carrying the G1 gene was constructed and designated as pcDNA3.1-G1. The expression of the target gene was confirmed in human embryonic kidney 293 (HEK 293) cells transfected with pcDNA3.1-G1 by indirect immunofluorescent staining. Immunisation experiments were intramuscularly carried out by vaccinating 6-week-old female mice in four groups, including the pcDNA3.1-G1 construct, pcDNA3.1 (+) plasmid alone, BEF-inactivated vaccine and phosphate-buffered saline (PBS) (1X) three times with 2-week intervals. Fourteen days after the last immunisation, the animals were bled and the resulting sera were tested for anti-G1-specific antibodies by immunoblotting analysis, indirect enzyme-linked immunosorbent assay (ELISA) and virus neutralisation (VN) test. Serological assays showed that the pcDNA3.1-G1 construct expressing G1 protein was able to elicit specific antibodies against this antigen. Virus neutralisation test showed that pcDNA3.1-G1 could induce anti-BEFV-neutralising antibodies in mice. Our findings indicated that a new dimension can be added to vaccine studies for bovine ephemeral fever (BEF) using eukaryotic expression plasmids encoding the G1 antigen in the future.
Показать больше [+] Меньше [-]Prevalence of canine Babesia and Ehrlichia co-infection and the predictive value of haematology
2018
Rautenbach, Yolandi(University of Pretoria Department of Companion Animal Clinical Studies) | Schoeman, Johan(University of Pretoria Department of Companion Animal Clinical Studies) | Goddard, Amelia(University of Pretoria Department of Companion Animal Clinical Studies)
Canine babesiosis and ehrlichiosis are important tick-borne infections in South Africa. Many South African general veterinary practitioners perceive co-infection with Ehrlichia spp. as a common occurrence in dogs with babesiosis. Studies about the prevalence of co-infection in South African dogs are lacking. This retrospective study aimed to determine the prevalence of Ehrlichia co-infection in dogs with babesiosis. Additionally, the predicative value of specific haematological variables for co-infection was evaluated. The study population consisted of 205 dogs diagnosed with canine babesiosis presented to the Onderstepoort Veterinary Academic Hospital (OVAH) in 2006 and between 2011 and 2013. The Babesia-infected dogs were grouped based on presence or absence of an Ehrlichia spp. co-infection. Ehrlichia spp. co-infection was confirmed using polymerase chain reaction. Positive and negative predictive values (PPVs and NPVs) of leukopenia or thrombocytopenia for co-infection were also calculated. The prevalence of Babesia spp. and Ehrlichia spp. co-infection in this cohort of dogs was 2%. In the babesiosis dogs, the PPV of leukopenia for co-infection with Ehrlichia spp. was 1.3%, and the NPV 97.4%. Similarly, the PPV and NPVs of thrombocytopenia for co-infection were 2.1% and 100%, respectively. Co-infection with Ehrlichia spp. was a rare occurrence in dogs with babesiosis presented to the OVAH. Normal leukocyte or platelet counts confidently ruled out the presence of concurrent ehrlichiosis in this cohort of dogs. However, the diagnosis of Ehrlichia co-infection based on the presence of thrombocytopenia or leukopenia would have been associated with false positive results in more than 97.4% of cases.
Показать больше [+] Меньше [-]Amphistome infections in domestic and wild ruminants in East and Southern Africa: A review
2018
Pfukenyi, Davies M.(University of Zimbabwe Faculty of Veterinary Science ,University of KwaZulu-Natal School of Life Sciences) | Mukaratirwa, Samson(University of KwaZulu-Natal School of Life Sciences)
In this article, the main amphistome species infecting domestic and wild ruminants in East and Southern Africa, their snail intermediate hosts and epidemiological features are reviewed and discussed. Twenty-six amphistome species belonging to nine genera from three families occur in domestic and wild ruminants in the region under review and over 70% of them belong to the genera Calicophoron, Carmyerius and Cotylophoron. Of the amphistome species, 76.9% are shared between domestic and wild ruminant hosts - an important observation when considering the different options for control. Seven freshwater snail species belonging to four genera from two families act as intermediate hosts of the identified amphistome species, with the genus Bulinus contributing 57% of the snail species. Some of the snails are intermediate hosts of amphistome species belonging to the same genus or to different genera; a phenomenon not yet fully elucidated as some snails are reported to be naturally infected with amphistome cercariae of unidentified species. Only nine (34.6%, 9/26) of the amphistome species have known snail intermediate hosts, while most (65.4%, 17/26) have unknown hosts. Species of intermediate hosts and the potential of the flukes to infect these hosts, the biological potential of the snail hosts, the definitive hosts management systems and their grazing habits are considered to be the main factors influencing the epidemiology of amphistomosis. Based on the epidemiological features of amphistome infections, various practical control options are discussed. Further research is necessary to determine amphistome-snail associations, develop diagnostic tests that can detect prepatent infections in the definitive host, determine the burden and economic importance of amphistomosis in domestic and wild ruminants and the efficacy of different anthelmintics in the treatment of patent infections.
Показать больше [+] Меньше [-]Comparison of the percentage of the C3-C7 vertebral canal occupied by the spinal cord in small-breed dogs with that in Doberman Pinschers and Great Danes with and without cervical spondylomyelopathy
2018
Bonelli, Marilia de A. | Da Costa, Ronaldo C.
OBJECTIVE To compare the percentage of the C3-C7 vertebral canal occupied by the spinal cord in small-breed dogs with that in Doberman Pinschers and Great Danes with and without cervical spondylomyelopathy (CSM). ANIMALS 30 small-breed dogs (body weight, < 15 kg), 15 clinically normal Doberman Pinschers, 15 Doberman Pinschers with CSM, 15 clinically normal Great Danes, and 15 Great Danes with CSM. PROCEDURES In a retrospective study, sagittal and transverse T2-weighted MRI images of the cervical (C3 to C7) vertebral column obtained from dogs that met study criteria and were free of extensive abnormalities that could affect the spinal cord diameter between January 2005 and February 2015 were reviewed. The area and height of the vertebral column and spinal cord were measured at the cranial and caudal aspect of each vertebra from C3 to C7, and the percentage of the vertebral canal occupied by the spinal cord at each location was calculated and compared among groups of dogs. RESULTS Mean percentage of the vertebral canal occupied by the spinal cord was greatest for small-breed dogs and lowest for Great Danes, but did not differ between Doberman Pinschers and small-breed dogs at approximately half of the locations evaluated or between Doberman Pinschers with and without CSM or between Great Danes with and without CSM. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the percentage of the vertebral canal occupied by the spinal cord, although expected to increase with vertebral canal stenosis, may not have a primary role in the pathogenesis of CSM.
Показать больше [+] Меньше [-]Comparison of angiographic dyes and injection techniques for ocular anterior segment angiography in horses
2018
Pirie, Chris G. | LoPinto, Alexander J. | Tenney, Wade A.
OBJECTIVE To assess and compare 2 injection techniques for conducting ocular anterior segment indocyanine green angiography (ASICGA) and sodium fluorescein (SF) angiography in horses. ANIMALS 3 healthy adult female horses (age range, 19 to 25 years). PROCEDURES Horses were sedated, jugular catheters were placed, and manual restraint was used to ensure proper positioning for the angiography procedure. Two injection techniques (IV and intra-arterial) were performed for each horse 1 week apart. Intravenous injections of 0.25% indocyanine green (ICG; 50 mg) and 10% SF (10 mg/kg) were administered via the jugular catheter. Intra-arterial injections of ICG (1 mg) and SF (1 mg/kg) were administered into the common carotid artery with ultrasound guidance. Angiography was performed by use of an adaptor system comprised of a modified digital single-lens reflex camera, camera adaptor, and lens. Imaging was performed at a rate of 3 images/s for 60 seconds immediately following ICG injection, then at 2, 3, 4, and 5 minutes after injection. The SF was injected 5 minutes thereafter. RESULTS ASICGA allowed visual identification of the arterial, capillary, and venous phases of angiography. Intra-arterial administration provided superior dye fluorescence, sharper contrast, and faster dye passage than IV administration. Visibility of the iris vasculature was limited with SF, and extravasation of SF was noted. No clinically important adverse events were detected. CONCLUSIONS AND CLINICAL RELEVANCE ASICGA images were obtainable with both injection techniques; however, visibility of the iris vasculature was better with intra-arterial administration of ICG. The ASICGA technique may serve as a viable ocular imaging modality for horses.
Показать больше [+] Меньше [-]Hyaluronic acid synthase-2 gene transfer into the joints of Beagles by use of recombinant adeno-associated viral vectors
2018
Kyostio-Moore, Sirkka | Berthelette, Patricia | Cornell, Cathleen Sookdeo | Nambiar, Bindu | Figueiredo, Monica Dias
OBJECTIVE To evaluate gene transfer of recombinant adeno-associated viral (rAAV) vectors with AAV2 or AAV5 capsid and encoding hyaluronic acid (HA) synthase-2 (HAS2) into joints of healthy dogs. ANIMALS 22 purpose-bred Beagles. PROCEDURES Plasmid expression cassettes encoding canine HAS2 (cHAS2) were assessed in vitro for concentration and molecular size of secreted HA. Thereafter, rAAV2-cHAS2 vectors at 3 concentrations and rAAV5-cHAS2 vectors at 1 concentration were each administered intra-articularly into the left stifle joint of 5 dogs; 2 dogs received PBS solution instead. Synovial fluid HA concentration and serum and synovial fluid titers of neutralizing antibodies against AAV capsids were measured at various points. Dogs were euthanized 28 days after treatment, and cartilage and synovium samples were collected for vector DNA and mRNA quantification and histologic examination. RESULTS Cell transfection with plasmids encoding cHAS2 resulted in an increase in production and secretion of HA in vitro. In vivo, the rAAV5-cHAS2 vector yielded uniform genome transfer and cHAS2 expression in collected synovium and cartilage samples. In contrast, rAAV2-cHAS2 vectors were detected inconsistently in synovium and cartilage samples and failed to produce clear dose-related responses. Histologic examination revealed minimal synovial inflammation in joints injected with rAAV vectors. Neutralizing antibodies against AAV capsids were detected in serum and synovial fluid samples from all vector-treated dogs. CONCLUSIONS AND CLINICAL RELEVANCE rAAV5-mediated transfer of the gene for cHAS2 into healthy joints of dogs by intra-articular injection appeared safe and resulted in vector-derived cHAS2 production by synoviocytes and chondrocytes. Whether this treatment may increase HA production by synoviocytes and chondrocytes in osteoarthritic joints remains to be determined.
Показать больше [+] Меньше [-]Pharmacokinetics of fentanyl after intravenous administration in isoflurane-anesthetized red-tailed hawks (Buteo jamaicensis) and Hispaniolan Amazon parrots (Amazona ventralis)
2018
Pascoe, Peter J. | Pypendop, Bruno H. | Pavez Phillips, Juan C. | DiMaio Kynch, Heather K. | Sanchez-Migallon Guzman, David | Hawkins, Michelle G.
OBJECTIVE To compare the disposition of fentanyl citrate after a single IV injection in isoflurane-anesthetized red-tailed hawks (Buteo jamaicensis) and Hispaniolan Amazon parrots (Amazona ventralis). ANIMALS 6 adult red-tailed hawks and 6 adult Hispaniolan Amazon parrots. PROCEDURES Anesthesia was induced and maintained with isoflurane; intermittent positive-pressure ventilation was provided. The minimum alveolar concentration of isoflurane was determined for each bird by use of the bracketing method and a supramaximal electrical stimulus. Fentanyl (20 μg/kg) was administered IV. Arterial (red-tailed hawks) or jugular venous (Hispaniolan Amazon parrots) blood samples were obtained immediately before and 1, 2, 4, 8, 15, 30, 60, 120, 180, 240, and 480 minutes (red-tailed hawks) and 1, 5, 10, 15, 30, 60, 120, and 180 minutes (Hispaniolan Amazon parrots) after fentanyl administration. RESULTS A 3-compartment and a 2-compartment model best described fentanyl pharmacokinetics in red-tailed hawks and Hispaniolan Amazon parrots, respectively. Median apparent volume of the central compartment and volume of distribution at steady state were 222 mL/kg and 987 mL/kg, respectively, for the red-tailed hawks and 5,108 mL/kg and 13,079 mL/kg, respectively, for the Hispaniolan Amazon parrots. Median clearance and elimination half-life were 8.9 mL/min/kg and 90.22 minutes, respectively, for the red-tailed hawks and 198.8 mL/min/kg and 51.18 minutes, respectively, for the Hispaniolan Amazon parrots. CONCLUSIONS AND CLINICAL RELEVANCE Pharmacokinetic results for fentanyl in isoflurane-anesthetized red-tailed hawks and Hispaniolan Amazon parrots indicated large differences and should strongly discourage extrapolation of doses between these 2 species.
Показать больше [+] Меньше [-]The biological characteristics of sheep umbilical cord mesenchymal stem cells
2018
Chen, F. | Zhao, C. | Zhao, Y. | Li, L. | Liu, S. | Zhu, Z. | Guan, W.
Although mesenchymal stem cells (MSCs) are now regarded as a promising cell resource for tissue repair and regeneration, the optimal source of MSCs has not yet been determined. The objective of this study was to provide a theoretical basis for the clinical application of umbilical cord mesenchymal stem cells (UCMSCs) in the future. Umbilical cord is an easily obtainable tissue resource, which is one reason that it has become a candidate resource for mesenchymal stem cells. In this study, we analyzed the biological characteristics of UCMSCs, such as their multiple differentiation and clone-forming ability, through morphological observation, reverse transcription polymerase chain reaction (RT-PCR), growth curve, positive rate test, and immunophenotype. Umbilical cord MSCs were successfully isolated and passaged to 29 generations. The results from RT-PCR showed that UCMSCs were positive for CD29, CD44, CD73, but negative for CD34. The expression of the stem cell marker nucleostemin and tenocyte-related markers showed similar positive results with CD44, CD73, and CD90. In addition, UCMSCs can be induced to differentiate into osteoblasts, adipocytes, or chondrocytes. Our study showed that UCMSCs not only have the ability to self-renew, but also have the potential to differentiate into multiple lineages. In general, we concluded that UCMSCs are a reliable source for use in cell therapy.
Показать больше [+] Меньше [-]Comparison of tensile strength and time to closure between an intermittent Aberdeen suture pattern and conventional methods of closure for the body wall of dogs
2018
Bula, Edyta | Upchurch, David A. | Wang, Yuheng | Chen, Sheng | Roccabianca, Sara
OBJECTIVE To compare tensile strength and time to completion of body wall closure among 3 suture patterns. SAMPLE Eighteen 5 × 5-cm leather specimens and sixty-eight 5 × 5-cm full-thickness tissue specimens from the ventral portion of the abdominal body wall of 17 canine cadavers. PROCEDURES During experiment 1 of a 2-experiment study, each leather specimen was cut in half and sutured with a simple interrupted or simple continuous pattern or continuous pattern with intermittent Aberdeen knots (intermittent Aberdeen pattern). During experiment 2, 4 tissue specimens were obtained from each cadaver; the linea alba of 3 specimens was incised and closed with 1 of the 3 suture patterns evaluated in experiment 1, and the fourth specimen was left intact as a control. All leather and tissue specimens underwent mechanical testing. Time to completion, mode of failure, and maximum force at failure (Fmax) were compared among the suture patterns. RESULTS In experiment 1, the mean Fmax for the simple continuous and intermittent Aberdeen patterns was significantly greater than that for the simple interrupted pattern. In experiment 2, the mean Fmax for specimens obtained cranial to the umbilicus was greater than that for specimens obtained caudal to the umbilicus, and the mean time to completion for both continuous suture patterns was significantly less than that for the simple interrupted pattern. Most (34/51) sutured tissue specimens failed because the suture cut through the tissue at the suture-tissue interface. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the intermittent Aberdeen pattern may be an alternative for body wall closure in dogs.
Показать больше [+] Меньше [-]Cyclooxygenase-2 expression in the eyes of cats with and without uveitis
2018
Sim, Zhi Hui | Pinard, Chantale L. | Plattner, Brandon L. | Bienzle, Dorothee
OBJECTIVE To characterize the distribution and intensity of cyclooxygenase (COX)-2 expression in the eyes of cats with and without uveitis and to determine whether COX-2 expression is correlated with severity of inflammation. SAMPLES Archived ocular tissue specimens from 51 cats with and 10 cats without ocular disease. PROCEDURES Specimens from only 1 eye were evaluated for each cat. Specimens were stained with H&E stain or immunohistochemical stain for detection of COX-2 and reviewed. For each eye, the type, severity, and distribution of inflammation and the distribution and intensity of COX-2 expression were determined for the uvea and other ocular tissues. Correlation between COX-2 expression and inflammation severity was also assessed. RESULTS COX-2 was not expressed in any nondiseased eye. Of the 51 diseased eyes, 20 had histologic evidence of lymphocytic-plasmacytic uveitis, 13 had neutrophilic uveitis, 11 had diffuse iris melanoma with uveitis, and 7 had diffuse iris melanoma without uveitis. Of the 44 eyes with uveitis, COX-2 was detected in the uvea of 16, including 11 eyes with lymphocytic-plasmacytic uveitis, 4 with neutrophilic uveitis, and 1 with diffuse iris melanoma–induced uveitis. Inflammation was severe, moderate, or mild in 10, 5, and 1 of those eyes, respectively. Cyclooxygenase-2 was detected in the cornea of 21 eyes with uveitis and 1 eye with diffuse iris melanoma without uveitis. Uveitis severity was positively correlated with COX-2 expression in both the uvea and cornea. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that COX-2 is an inflammatory mediator in feline uveitis but not diffuse iris melanoma.
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