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Prevalence and mutation analysis of the spike protein in feline enteric coronavirus and feline infectious peritonitis detected in household and shelter cats in western Canada Texto completo
2020
McKay, L. A. | Meachem, M. | Snead, E. | Brannen, T. | Mutlow, N. | Ruelle, L. | Davies, J. L. | Van der Meer, F.
Feline infectious peritonitis (FIP) is a fatal disease for which no simple antemortem diagnostic assay is available. A new polymerase chain reaction (PCR) test has recently been developed that targets the spike protein region of the FIP virus (FIPV) and can identify specific mutations (M1030L or S1032A), the presence of which indicates a shift from feline enteric coronavirus (FeCV) to FIPV. This test will only be useful in the geographical region of interest, however, if the FIP viruses contain these mutations. The primary objective of this study was to determine the presence of the M1030L or S1032A mutations in FeCV derived from stool samples from a selected group of healthy cats from households and shelters and determine how many of these cats excrete FeCV. The secondary objective was to evaluate how often these specific FIPV mutations were present in tissue samples derived from cats diagnosed with FIP at postmortem examination. Feline enteric coronavirus (FeCV) was detected in 46% of fecal samples (86/185), all were FeCV type 1, with no difference between household or shelter cats. Only 45% of the FIPV analyzed contained the previously reported M1030L or S1032A mutations. It should be noted that, as the pathological tissue samples were opportunistically obtained and not specifically obtained for PCR testing, caution is warranted in interpreting these data.
Mostrar más [+] Menos [-]Reliability of kinetic measurements of healthy dogs examined while walking on a treadmill Texto completo
2020
Pietsch, Sebastian | Steigmeier-Raith, Stephanie | Reese, Sven | Meyer-Lindenberg, Andrea
OBJECTIVE To investigate whether an actual improvement in gait could be differentiated from physiologic differences or habituation effects during gait analysis of dogs. ANIMALS 11 healthy dogs. PROCEDURES On 4 examination days, kinetic parameters were measured while dogs were walking on a treadmill. Differences in mean parameter values and habituation effects (ie, effect sizes) were quantified and compared among examination days. Coefficients of variation for repeated measurements were calculated to determine measurement reproducibility, and minimum differences were calculated to distinguish between physiologic fluctuation and an actual change in gait pattern. RESULTS Among the 4 examination days, mean absolute differences in peak vertical force and vertical impulse (VI) varied from 1.5% to 5.3% of body weight (BW) and 0.9% to 1.8% of BW·s, respectively. Mean absolute differences in the percentage of stance-phase duration (%SPD) and relative stride length (RSL) varied from 0.9% to 3.2% and 1.7% to 3.0%, respectively. Reproducibility of parameter measurements was good. Values for %SPD had the lowest amount of dispersion and largest effect size, suggesting a habituation effect for this parameter. Calculated minimum differences among the days for peak vertical force, VI, %SPD, and RSL did not exceed 9.9% of BW, 3.3% of BW·s, 5.8 percentage points, and 5.2 percentage points, respectively. CONCLUSIONS AND CLINICAL RELEVANCE The %SPD of healthy dogs walking on a treadmill was the most sensitive and diagnostically reliable of the measured kinetic parameters, in contrast to VI and RSL. Findings suggested that actual changes can be distinguished from random physiologic fluctuations during gait analysis of dogs.
Mostrar más [+] Menos [-]Stability of canine urine samples under different storage conditions Texto completo
2020
Neumann, Stephan | Fechner, Kim | Czerny, C.-P. (Claus-Peter)
The stability of canine urine samples is essential when the samples cannot be analyzed immediately. The objective of this study was to investigate the stability of canine urine samples at room temperature and under refrigerated conditions. Samples from 20 dogs were collected, divided, and stored at 4°C and 20°C. The samples were examined up to 48 h after collection for specific gravity, pH, protein, bilirubin, glucose, ketones, and sediment and at 4 h and 24 h for bacterial growth. Specific gravity and all chemistry parameters were stable for a minimum of 48 h in 90% of samples. The sediment was stable, apart from crystals. The bacterial growth of 3 bacterial species tested in vitro, as well as the clinical samples, was mostly constant over 24 h at the refrigerated temperature. In urine samples stored at room temperature, the total number of aerobic growing bacteria was increasing. The results of our study showed that routinely measured parameters were stable in unpreserved urine for a minimum of 4 h and up to 48 h in most cases. If it is not possible to culture urine immediately, it is recommended that urine samples be stored at 4°C for a period of up to 24 h.
Mostrar más [+] Menos [-]Antioxidative enzyme activity and total antioxidant capacity in serum of dogs with degenerative mitral valve disease Texto completo
2020
Michalek, M. | Tabis, A. | Noszcyk-Nowak, A.
This study was designed to evaluate the antioxidative status of serum by measuring its total antioxidant capacity, as well as the antioxidant enzyme activity (superoxide dismutase, catalase, and glutathione reductase), in dogs with various stages of degenerative mitral valve disease (DMVD) compared to healthy controls. In total, 71 client-owned dogs in different stages of DMVD, which included healthy controls, took part in the study. Following an anamnesis, clinical examination, standard transthoracic echocardiograpic examination, chest X-ray, complete blood (cell) count, and serum biochemistry, dogs were divided into 2 study groups. Blood was drawn from each dog once at the time of presentation and selected antioxidant parameters were measured using commercially available assay kits. The activity of superoxide dismutase gradually decreased in the more advanced stages of DMVD, while the activity of catalase was significantly higher in the group of dogs with asymptomatic DMVD compared to healthy controls and dogs with symptomatic DMVD. No significant changes were noted in total antioxidant capacity and the activity of glutathione reductase. Results suggested that DMVD has a significant impact on the activity of superoxide dismutase and catalase in the serum of the tested dogs. Knowledge of changes in the activity of antioxidative enzymes may warrant further studies, possibly to evaluate the potential role of compounds with antioxidative properties in the clinical outcome of dogs with DMVD.
Mostrar más [+] Menos [-]Correlation of Activity Data in Normal Dogs to Distance Traveled Texto completo
2020
Eskander, Bishoy S. | Barbar, Megan | Evans, Richard B. | Enomoto, Mastaka | Lascelles, B. Duncan X. | Conzemius, Michael G.
The objective of this study was to explore the mathematical relationships between independent variables (patient morphometrics and treadmill speed) and dependent variables (accelerometer or pedometer output) when evaluating data from accelerometers and pedometers in dogs. Twenty dogs took part in 3 randomized activities, consisting of exercise on a treadmill at 1.0, 1.5, and 2.0 m/s for a total distance of 1 km at each speed. Dogs simultaneously wore both an accelerometer and a pedometer. Statistical analysis used multiple regression models to discover the relationships between independent and dependent variables. A formula was developed to predict the distance traveled by a dog based on its morphometrics and activity monitor output. Shoulder height had stronger correlations to accelerometer and pedometer outputs than other morphometric variables. As shoulder height increased, all accelerometer and pedometer outputs decreased. As treadmill speed increased, both accelerometer and pedometer step counts decreased, while accelerometer activity counts increased. According to a formula derived to predict the total distance traveled using patient shoulder height and accelerometer or pedometer output, pedometer steps were the most accurate predictor of distance traveled. Accelerometer steps were less accurate when using the same model. Accelerometer activity counts did not reveal a meaningful predictive formula. The results of this study indicate that patient morphometrics and treadmill speed (as a measure of intensity) influenced accelerometer and pedometer data. The pedometer data more precisely and accurately estimated the distance traveled based on step counts and patient shoulder height. In normal dogs, accelerometer and pedometer steps may reasonably estimate distance traveled.
Mostrar más [+] Menos [-]Pharmacokinetics of hydromorphone hydrochloride after intramuscular and intravenous administration of a single dose to orange-winged Amazon parrots (Amazona amazonica) Texto completo
2020
Sanchez-Migallon Guzman, David | Knych, Heather | Douglas, Jamie | Paul-Murphy, Joanne R.
OBJECTIVE To evaluate the pharmacokinetics of hydromorphone hydrochloride after IM and IV administration to orange-winged Amazon parrots (Amazona amazonica). ANIMALS 8 orange-winged Amazon parrots (4 males and 4 females). PROCEDURES Hydromorphone (1 mg/kg) was administered once IM. Blood samples were collected 5 minutes and 0.5, 1.5, 2, 3, 6, and 9 hours after drug administration. Plasma hydromorphone concentrations were determined with liquid chromatography-tandem mass spectrometry, and pharmacokinetic parameters were calculated with a compartmental model. The experiment was repeated 1 month later with the same dose of hydromorphone administered IV. RESULTS Plasma hydromorphone concentrations were > 1 ng/mL for 6 hours in 8 of 8 and 6 of 7 parrots after IM and IV injection, respectively. After IM administration, mean bioavailability was 97.6%, and mean maximum plasma concentration was 179.1 ng/mL 17 minutes after injection. Mean volume of distribution and plasma drug clearance were 4.24 L/kg and 64.2 mL/min/kg, respectively, after IV administration. Mean elimination half-lives were 1.74 and 1.45 hours after IM and IV administration, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Hydromorphone hydrochloride had high bioavailability and rapid elimination after IM administration, with rapid plasma clearance and a large volume of distribution after IV administration in orange-winged Amazon parrots. Drug elimination half-lives were short. Further pharmacokinetic studies of hydromorphone and its metabolites, including investigation of multiple doses, different routes of administration, and sustained-release formulations, are recommended.
Mostrar más [+] Menos [-]Prevalence of feline herpesvirus-1, feline calicivirus, Chlamydia felis, and Bordetella bronchiseptica in a population of shelter cats on Prince Edward Island Texto completo
2020
Walter, Julie | Foley, Peter | Yason, Carmencita | Vanderstichel, Raphael | Muckle, Ann
The prevalence of the causative agents of feline upper respiratory tract disease (URTD) has been previously documented in many regions worldwide, but has yet to be reported in eastern Canada. The objectives of this study were to determine the prevalence of feline herpesvirus(-1) (FHV(-1)), feline calicivirus (FCV), Chlamydia felis (C. felis), and Bordetella bronchiseptica (B. bronchiseptica) in a population of shelter cats with clinical signs related to URTD on Prince Edward Island, Canada; to compare the prevalence of FHV(-1) and FCV as detected by polymerase chain reaction (PCR) and virus isolation (VI) in this population; and lastly, to determine whether factors, such as co-infections, time of year, concurrent feline leukemia virus (FeLV)- or feline immunodeficiency virus (FIV)-positive status, or clinical signs, were associated with prevalence of particular pathogens. Conjunctival, nasal mucosal, and oropharyngeal swabs were collected from 82 cats with clinical signs consistent with URTD. Samples were pooled in transport medium and PCR was used to detect FHV(-1), FCV, and C. felis and VI was also used to detect FHV(-1) and FCV. A separate swab was submitted for aerobic bacterial culture to detect B. bronchiseptica. Feline herpesvirus(-1) (FHV(-1)) was the most prevalent in this population, followed by C. felis, B. bronchiseptica, and FCV. Of the 4 cats that were positive for B. bronchiseptica, 3 were concurrently positive for FHV(-1). All positive B. bronchiseptica cultures were resistant to cefovecin. The prevalence for FHV(-1) was lowest in autumn (seasons P < 0.001) and was positively associated with the presence of nasal discharge (P = 0.018) and coughing (P = 0.043).
Mostrar más [+] Menos [-]A potential approach for assessing the quality of human and nonhuman adenoviral vector preparations Texto completo
2020
Sayedahmed, Ekramy E. | Mittal, Suresh K.
Various types of human and nonhuman adenoviral (AdV) vectors are being used as gene delivery vectors in preclinical and clinical investigations. The objective of this study was to determine the ratio between the 2 best assays that would effectively address the variability in the titration of various AdV vectors in different cell lines and help obtain consistent results in preclinical and clinical studies using different AdV vectors. Here, we compared plaque-forming units, tissue culture infectious dose 50, focus-forming units (FFU), virus particle (VP) count, and genome copy number (GCN) of purified preparations of human AdV type C5, bovine AdV type 3, and porcine AdV type 3 to determine a correlation between infectious and noninfectious virus particles. Our results suggest that a VP:FFU or a VP:GCN ratio could accurately reflect the quality of an AdV preparation and could serve as an indicator to control batch-to-batch variability.
Mostrar más [+] Menos [-]In-vitro effects of taurolidine alone and in combination with mitoxantrone and/or piroxicam on canine transitional cell carcinoma Texto completo
2020
Byer, Brittney | Schlein, Lisa J. | Rose, Barbara | Seguin, B. (Bernard)
The objective of this in-vitro study was to evaluate taurolidine as a therapy for transitional cell carcinomas in canine patients. Transitional cell carcinoma (TCC) is the most common cancer of the urinary bladder in dogs and accounts for approximately 2% of reported malignancies in this species. There is no cure for this neoplasm and most dogs are lost from complications associated with progression of the local disease. Taurolidine has been shown to have anti-tumor and antiangiogenic effects against a variety of neoplasms in human and animal models. Four canine TCC cell lines were treated with various concentrations of taurolidine, mitoxantrone, and piroxicam alone. In addition, combinations of taurolidine/mitoxantrone, taurolidine/piroxicam, mitoxantrone/piroxicam, and taurolidine/mitoxantrone/piroxicam were assessed. Susceptibility of the TCC cell lines was based on a 72-hour growth inhibition assay using resazurin with absorbance measured at 530/590. The ability of taurolidine to induce apoptosis was evaluated on 2 of the cell lines with an Annexin-V/propidium iodide assay. All cell lines were susceptible to treatment with taurolidine, mitoxantrone, and piroxicam alone. The results of the combination therapies of the 3 drugs were dependent on cell line and concentration and revealed no change in cell growth inhibition, a subadditive relationship, or a synergistic relationship. Taurolidine induced apoptosis in a concentration- and time-dependent fashion. Taurolidine alone showed significant effects on cell viability in vitro in canine TCC cell lines and these effects can be potentially enhanced with the addition of mitoxantrone and/or piroxicam.
Mostrar más [+] Menos [-]Efficacy of afoxolaner plus milbemycin oxime and afoxolaner alone as treatment for sarcoptic mange in naturally infested dogs Texto completo
2020
Romero Núñez, Camilo | Bautista-Gomez, Linda G. | Shienberg, Galia | Martin-Cordero, Alberto | Flores-Ortega, Ariadna | Heredia-Cardenas, Rafael
Sarcoptic mange is a pruritic, contagious, ectoparasitic skin disease that affects mammals, including the domestic dog. The objective of this study was to evaluate and compare the efficacy of afoxolaner plus milbemycin oxime (NexGard Spectra) and afoxolaner alone (NexGard) as treatments for sarcoptic mange in naturally infested dogs. A total of 142 dogs naturally infested with Sarcoptes scabiei was evaluated. The dogs were diagnosed by microscopic examinations of skin scrapings. The dogs were divided into 2 groups: 96 dogs were treated with a combined dosage of 2.50 to 5.36 mg/kg body weight (BW) of afoxolaner and 0.50 to 1.07 mg/kg BW of milbemycin oxime and 46 dogs were treated with 2.50 mg/kg BW of afoxolaner alone. The presence or absence of pruritus and lesions were evaluated using an analogous scale on days 7, 14, 21, 28, and 56 after receiving the treatment. Data obtained were analyzed by Student's t-test (P ≤ 0.05). The single oral treatment of afoxolaner plus milbemycin oxime resulted in a significant reduction in pruritus of 87.4% at 28 d after treatment (P ≤ 0.05). Resolution of the lesions after treatment was variable, with a significant decrease (P ≤ 0.05) observed within the first 14 d, although this parameter continued to improve until the end of the study on day 28, when a decrease of 96% was observed. By the end of the study, a single dose of either the afoxolaner alone or the afoxolaner combined with milbemycin oxime was effective in significantly reducing the signs associated with sarcoptic mange during a 56-day evaluation period.
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