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Quantitative analysis of brain perfusion in healthy dogs by means of magnetic resonance imaging
2016
Hartmann, Antje | Driesen, Agnes | Lautenschlager, Ines E. | Scholz, Volkher B. | Schmidt, Martin J.
OBJECTIVE To determine values of perfusion parameters determined via MRI in the brains of healthy dogs. ANIMALS 10 healthy adult Beagles. PROCEDURES Each dog was anesthetized for MRI examination of the brain, including standard sequences and a perfusion-weighted sequence. Gadoteric acid (0.2 mmol/kg) was injected IV at a rate of 5 mL/s. A dedicated workstation was used to measure the times from contrast medium injection to arrival at an ROI (TO) and peak contrast enhancement (TTP), mean contrast medium transport time (MTT), and cerebral blood flow (CBF) in the caudate nucleus, thalamus, piriform lobe, hippocampus, semioval center, and temporal cerebral cortex. A simple mathematical model was used to compare parameter values among the various brain regions. RESULTS T0 and time to peak contrast enhancement had a significant linear relationship. A significant negative correlation was identified between T0 and CBF and, to a lesser extent, between MTT and CBF. Differences among brain regions were significant for MTT and CBF. The CBF was lowest in the semioval center, and the piriform lobe had almost 2-fold the CBF of that region. No significant differences were identified between hemispheres of the brain. CONCLUSIONS AND CLINICAL RELEVANCE Findings obtained in this study involving healthy dogs may serve as a reference for MRI perfusion measurements in specific brain regions and may help in the characterization of various brain diseases in dogs.
Afficher plus [+] Moins [-]Effects of ischemia and reperfusion on eosinophilic accumulation and distribution in mucosa of equine jejunum and colon
2016
Rotting, Anna K. | Freeman, David E. | Constable, Peter D. | Eurell, Jo Ann C. | Wallig, Matt A.
OBJECTIVE To evaluate the eosinophilic response in intestinal mucosa of horses with intestinal ischemia and reperfusion or with strangulation of the jejunum or colon. SAMPLE Mucosal samples from horses with naturally occurring strangulation (n = 24 horses) or distention (n = 6) of the jejunum or colon (11), with experimentally induced ischemia and reperfusion of the jejunum (6) or colon (15), or that were euthanized for reasons other than gastrointestinal tract disease (13). PROCEDURES Mucosal samples were collected and grouped by type of intestinal injury. Slides were stained with Luna eosinophil stain and histologically examined to determine eosinophil accumulation and distribution. Number of eosinophils per mm2 of mucosa was calculated as a measure of eosinophil accumulation. Additionally, mucosa was categorized into 5 regions; the percentage of eosinophils in each of the 5 regions, relative to the total eosinophil count in all regions, was determined. RESULTS Eosinophil migration toward and onto the luminal surface was evident in tissues after ischemia and reperfusion and after naturally occurring strangulating disease of the jejunum and colon, as indicated by a decrease in the number of eosinophils near the muscularis mucosa and an increase in the number of eosinophils on or near the luminal surface. Ischemia alone did not change eosinophil distribution in the jejunum or colon. CONCLUSIONS AND CLINICAL RELEVANCE Eosinophils responded to mucosal damage evoked by ischemia and reperfusion by migration toward and onto the luminal surface. This migration could represent an important component of the inflammatory response to injury in equine gastrointestinal mucosa.
Afficher plus [+] Moins [-]Effect of in ovo administration of an adult-derived microbiota on establishment of the intestinal microbiome in chickens
2016
Pedroso, Adriana A. | Batal, Amy B. | Lee, Margie D.
OBJECTIVE To determine effects of in ovo administration of a probiotic on development of the intestinal microbiota of 2 genetic lineages (modern and heritage) of chickens. SAMPLE 10 newly hatched chicks and 40 fertile eggs to determine intestinal microbiota at hatch, 900 fertile eggs to determine effects of probiotic on hatchability, and 1,560 chicks from treated or control eggs. PROCEDURES A probiotic competitive-exclusion product derived from adult microbiota was administered in ovo to fertile eggs of both genetic lineages. Cecal contents and tissues were collected from embryos, newly hatched chicks, and chicks. A PCR assay was used to detect bacteria present within the cecum of newly hatched chicks. Fluorescence in situ hybridization and vitality staining were used to detect viable bacteria within intestines of embryos. The intestinal microbiota was assessed by use of 16S pyrosequencing. RESULTS Microscopic evaluation of embryonic cecal contents and tissues subjected to differential staining techniques revealed viable bacteria in low numbers. Development of the intestinal microbiota of broiler chicks of both genetic lineages was enhanced by in ovo administration of adult microbiota. Although the treatment increased diversity and affected composition of the microbiota of chicks, most bacterial species present in the probiotic were transient colonizers. However, the treatment decreased the abundance of undesirable bacterial species within heritage lineage chicks. CONCLUSIONS AND CLINICAL RELEVANCE In ovo inoculation of a probiotic competitive-exclusion product derived from adult microbiota may be a viable method of managing development of the microbiota and reducing the prevalence of pathogenic bacteria in chickens.
Afficher plus [+] Moins [-]Distribution and activity levels of matrix metalloproteinase 2 and 9 in canine and feline osteosarcoma
2016
Gebhard, Christiane | Fuchs-Baumgartinger, Andrea | Razzazi-Fazeli, Ebrahim | Miller, Ingrid | Walter, Ingrid
Overexpression of matrix metalloproteinases (MMPs) has been associated with increased tumor aggressiveness and metastasis dissemination. We investigated whether the contrasting metastatic behavior of feline and canine osteosarcoma is related to levels and activities of MMP2 and MMP9. Zymography and immunohistochemistry were used to determine expression levels of MMP2 and MMP9 in canine and feline osteosarcoma. Using immunohistochemistry, increased MMP9 levels were identified in most canine osteosarcomas, whereas cat samples more often displayed moderate levels. High levels of pro-MMP9, pro-MMP2, and active MMP2 were detected by gelatin zymography in both species, with significantly higher values for active MMP2 in canine osteosarcoma. These findings indicate that MMP2 is probably involved in canine and feline osteosarcoma and their expression and activity could be associated with the different metastatic behavior of canine and feline osteosarcoma.
Afficher plus [+] Moins [-]Assessment of the expression of biomarkers of uremic inflammation in dogs with renal disease
2016
Nentwig, Alice | Schweighauser, Ariane | Maissen-Villiger, Carla | Bruckmaier, Rupert M. | Zurbriggen, Andreas | Dorland, H Anette van | Francey, Thierry
OBJECTIVE To assess the expression of inflammatory cytokines and enzymes in venous whole blood of dogs with impaired renal function attributable to various causes. ANIMALS 46 dogs with acute kidney injury (AKI), 8 dogs with chronic kidney disease (CKD), and 10 healthy dogs. PROCEDURES Dogs with AKI and CKD were prospectively enrolled during 2010 if they met inclusion criteria. Demographic and laboratory characteristics were evaluated for each dog, and expression of inflammatory cytokines (interleukin [IL]-1α, IL-1β, IL-8, tumor necrosis factor [TNF]-α, IL-10, and transforming growth factor [TGF]-β) and enzymes (inducible nitric oxide synthase [iNOS] and 5-lipoxygenase [5-LO]) was measured in venous whole blood obtained at initial evaluation. RESULTS Dogs with impaired renal function had markedly higher expression of the cytokines IL-1α, IL-1β, and TGF-β and the enzyme 5-LO, compared with expression in healthy dogs. Additionally, 17 of 46 AKI dogs (but none of the CKD dogs) had higher IL-8 mRNA expression and 3 of 8 CKD dogs (but only 2/46 AKI dogs) had higher TNF-α expression, compared with results for healthy dogs. No significant difference between renal disease groups was detected for inflammatory markers and laboratory variables, degree of azotemia, or cause of impaired renal function. CONCLUSIONS AND CLINICAL RELEVANCE In this study, expression of the cytokines IL-1α, IL-1β, and TGF-β and the enzyme 5-LO was clearly increased in dogs with renal disease, which suggested that these markers were part of an inflammatory response in animals with AKI or CKD.
Afficher plus [+] Moins [-]Efficacy of four commercially available multivalent modified-live virus vaccines against clinical disease, viremia, and viral shedding in early-weaned beef calves exposed simultaneously to cattle persistently infected with bovine viral diarrhea virus and cattle acutely infected with bovine herpesvirus 1
2016
Chamorro, Manuel F. | Walz, Paul H. | Passler, Thomas | Palomares, Roberto | Newcomer, Benjamin W. | Riddell, Kay P. | Gard, Julie | Zhang, Yijing | Galik, Patricia
OBJECTIVE To evaluate the efficacy of 4 commercially available multivalent modified-live virus vaccines against clinical disease, viremia, and viral shedding caused by bovine viral diarrhea virus (BVDV) and bovine herpesvirus 1 (BHV1) in early-weaned beef calves. ANIMALS 54 early-weaned beef steers (median age, 95 days). PROCEDURES Calves were randomly assigned to 1 of 5 groups and administered PBSS (group A [control]; n = 11) or 1 of 4 commercially available modified-live virus vaccines that contained antigens against BHV1, BVDV types 1 (BVDV1) and 2 (BVDV2), parainfluenza type 3 virus, and bovine respiratory syncytial virus (groups B [11], C [10], D [11], and E [11]). Forty-five days after vaccination, calves were exposed simultaneously to 6 cattle persistently infected with BVDV and 8 calves acutely infected with BHV1 for 28 days (challenge exposure). For each calf, serum antibody titers against BVDV and BHV1 were determined before vaccination and before and after challenge exposure. Virus isolation was performed on nasal secretions, serum, and WBCs at predetermined times during the 28-day challenge exposure. RESULTS None of the calves developed severe clinical disease or died. Mean serum anti-BHV1 antibody titers did not differ significantly among the treatment groups at any time and gradually declined during the study. Mean serum anti-BVDV antibody titers appeared to be negatively associated with the incidence of viremia and BVDV shedding. The unvaccinated group (A) had the lowest mean serum anti-BVDV antibody titers. The mean serum anti-BVDV antibody titers for group D were generally lower than those for groups B, C, and E. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated differences in vaccine efficacy for the prevention of BVDV viremia and shedding in early-weaned beef calves.
Afficher plus [+] Moins [-]Pharmacokinetics of bupivacaine after intraperitoneal administration to cats undergoing ovariohysterectomy
2016
Benito Fernández, Javier | Monteiro, Beatriz P. | Beaudry, Francis | Lavoie, Anne-Marie | Lascelles, B. Duncan X. | Steagall, Paulo V.
OBJECTIVE To evaluate pharmacokinetics of bupivacaine after IP administration to cats undergoing ovariohysterectomy. ANIMALS 8 healthy cats. PROCEDURES Anesthesia was induced with propofol and maintained with isoflurane. Buprenorphine (0.02 mg/kg, IV) and meloxicam (0.2 mg/kg, SC) were administered. A 20-gauge catheter was inserted into a jugular vein for blood sample collection. A ventral midline incision was made, and a solution of 0.5% bupivacaine (2 mg/kg) diluted with an equal volume of saline (0.9% NaCl) solution (final concentration, 0.25% bupivacaine) was injected into the peritoneal space over the right and left ovarian pedicles and caudal aspect of the uterus before ovariohysterectomy. Cats were monitored for signs of bupivacaine toxicosis. Venous blood samples (2 mL) were collected before (time 0) and 2, 5, 10, 15, 20, 30, 60, 120, and 240 minutes after bupivacaine administration. Plasma bupivacaine concentrations were determined with a liquid chromatography–tandem mass spectrometry method. Pharmacokinetic parameters were determined by data plotting followed by analysis with a noncompartmental model. RESULTS No signs of bupivacaine toxicosis were observed. Maximum bupivacaine plasma concentration was 1,030 ± 497.5 ng/mL at a mean ± SD value of 30 ± 24 minutes after administration. Mean elimination half-life was 4.79 ± 2.7 hours. Mean clearance indexed by bioavailability and volume of distribution indexed by bioavailability were 0.35 ± 0.18 L•h/kg and 2.10 ± 0.84 L/kg, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Intraperitoneal administration of bupivacaine resulted in concentrations that did not cause observable toxicosis. Studies to investigate analgesic effects for this technique in cats are warranted.
Afficher plus [+] Moins [-]Reinfection of adult cattle with rotavirus B during repeated outbreaks of epidemic diarrhea
2016
Hayashi, Michiko | Murakami, Toshiaki | Kuroda, Yoshizumi | Takai, Hikaru | Ide, Hisahiro | Awang, Ainani | Suzuki, Tohru | Miyazaki, Ayako | Nagai, Makoto | Tsunemitsu, Hiroshi
Rotavirus B (RVB) infection in cattle is poorly understood. The objective of this study was to describe the epidemiological features of repeated outbreaks of epidemic diarrhea due to RVB infection in adult cattle on a large dairy farm complex in Japan. In October 2002, approximately 550 adult cows and approximately 450 in February 2005 had acute watery diarrhea at several farms on the complex. Four months before the first outbreak, RVB antibody-positive rates at subsequently affected farms were significantly lower than at non-affected farms (30% to 32% versus 61% to 67%). During the acute phase of both outbreaks, RVB antibody-positive rates in diarrheal cows tested were as low as 15% to 26%. Most of the farms affected in the second outbreak were also involved in the first outbreak. Some adult cows with RVB diarrhea in the first outbreak showed not only RVB seroresponse, but also RVB shedding in the second outbreak, although none of these cows developed diarrhea. Nucleotide sequences of the VP7 and VP4 genes revealed a close relationship between RVB strains in both outbreaks. Taken together, these results indicate that outbreaks of epidemic RVB diarrhea in adult cows might be influenced by herd immunity and could occur repeatedly at the same farms over several years. To our knowledge, this is the first report on repeated RVB infections in the same cattle.
Afficher plus [+] Moins [-]An attempt to detect lameness in galloping horses by use of body-mounted inertial sensors
2016
Lopes, Marco A. F. | Dearo, Antonio C. O. | Lee, Allen D. | Reed, Shannon K. | Kramer, Joanne | Pai, Frank | Yonezawa, Yoshiharu | Maki, Hiromitchi | Morgan, Terry L. | Wilson, David A. | Keegan, Kevin G.
OBJECTIVE To evaluate head, pelvic, and limb movement to detect lameness in galloping horses. ANIMALS 12 Thoroughbreds. PROCEDURES Movement data were collected with inertial sensors mounted on the head, pelvis, and limbs of horses trotting and galloping in a straight line before and after induction of forelimb and hind limb lameness by use of sole pressure. Successful induction of lameness was determined by measurement of asymmetric vertical head and pelvic movement during trotting. Differences in gallop strides before and after induction of lameness were evaluated with paired-sample statistical analysis and neural network training and testing. Variables included maximum, minimum, range, and time indices of vertical head and pelvic acceleration, head rotation in the sagittal plane, pelvic rotation in the frontal plane, limb contact intervals, stride durations, and limb lead preference. Difference between median standardized gallop strides for each limb lead before and after induction of lameness was calculated as the sum of squared differences at each time index and assessed with a 2-way ANOVA. RESULTS Head and pelvic acceleration and rotation, limb timing, stride duration measurements, and limb lead preference during galloping were not significantly different before and after induction of lameness in the forelimb or hind limb. Differences between limb leads before induction of lameness were similar to or greater than differences within limb leads before and after lameness induction. CONCLUSIONS AND CLINICAL RELEVANCE Galloping horses maintained asymmetry of head, pelvic, and limb motion between limb leads that was unrelated to lameness.
Afficher plus [+] Moins [-]Assessment of novel digital and smartphone goniometers for measurement of canine stifle joint angles
2016
Freund, Kristin A. | Kieves, Nina R. | Hart, Juliette L. | Foster, Sasha A. | Jeffery, Unity | Duerr, Felix M.
OBJECTIVE To evaluate accuracy and reliability of 3 novel goniometers for measurement of canine stifle joint angles and compare the results with those obtained with a universal goniometer (UG). SAMPLE 8 pelvic limbs from 4 canine cadavers. PROCEDURES Each limb was secured to a wooden platform at 3 arbitrarily selected fixed stifle joint angles. Goniometry was performed with 2 smartphone-based applications (novel goniometers A and B), a digital goniometer (novel goniometer C), and a UG; 3 evaluators performed measurements in triplicate for each angle with each device. Results were compared with stifle joint angle measurements on radiographs (used as a gold standard). Accuracy was determined by calculation of bias and total error, coefficients of variation were calculated to estimate reliability, and strength of linear association between radiographic and goniometer measurements was assessed by calculation of correlation coefficients. RESULTS Mean coefficient of variation was lowest for the UG (4.88%), followed by novel goniometers B (7.37%), A (7.57%), and C (12.71%). Correlation with radiographic measurements was highest for the UG (r = 0.97), followed by novel goniometers B (0.93), A (0.90), and C (0.78). Constant bias was present for all devices except novel goniometer B. The UG and novel goniometer A had positive constant bias; novel goniometer C had negative constant bias. Total error at 50° and 100° angles was > 5% for all devices. CONCLUSIONS AND CLINICAL RELEVANCE None of the devices accurately represented radiographically measured stifle joint angles. Additional veterinary studies are indicated prior to the use of novel goniometers in dogs.
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