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L-lactate in cerebrospinal fluid can be used as a biomarker of encephalitis in cattle Texte intégral
2020
Curti, Juliana M. | Queiroz, Gustavo R. | Pereira, Priscilla F. V. | Anjos, Mayara C. | Flaiban, Karina K. M. C. | Lisboa, Julio A. N.
Cerebrospinal fluid (CSF) changes are significant for antemortem diagnoses of some neurological diseases. The aim of this study was to evaluate if the concentration of L-lactate in CSF could be used to differentiate healthy from encephalitic cattle. Cerebrospinal fluid samples from healthy cattle (n = 10) and from those naturally affected by rabies (n = 15), bovine herpesvirus type 5 meningoencephalitis (n = 16), histophilosis (n = 6), or bacterial encephalitis (n = 4), including 1 case of listeriosis, were collected and analyzed. Physical, biochemical (i.e., protein and glucose), and cellular analyses were performed in fresh samples. L-lactate, electrolytes (sodium, potassium, and chloride), calcium, and magnesium concentrations were measured in CSF samples that were kept frozen. L-lactate concentrations were also measured in plasma. Analysis of variance was used for comparison between groups and receiver operating characteristic analysis was performed considering L-lactate in CSF of healthy versus encephalitic cattle. The CSF L-lactate concentration was significantly higher in cattle with bacterial encephalitis than in healthy cattle; however, it did not differ between viral and bacterial encephalitis. The calcium concentrations were lower in cattle with encephalitis. L-lactate concentration in CSF > 3.6 mmol/L can be accepted as a cut-off value to indicate encephalitis. Thus, L-lactate in CSF is important for the diagnosis of encephalitis in cattle. Despite the small number of cases of bacterial encephalitis, it is suggested that L-lactate was not important for the differentiation between viral and bacterial encephalitis. Additional studies with a greater number of observations are necessary to clarify this, specifically in cases of listeriosis.
Afficher plus [+] Moins [-]Effects of the monoacylglycerol lipase inhibitor JZL184 on chickens infected with avian pathogenic Escherichia coli O78: A preliminary pharmacokinetic and infection study Texte intégral
2020
Ho, Cherry P. | Borazjani, Abdolsamad | Ross, Matthew K. | Wang, Chinling
The endocannabinoid (eCB) system modulates the degree of injury caused by inflammation, while enhancing the activity of phagocytes that promote resolution of inflammation and tissue repair. In-vitro studies with the monoacylglycerol lipase (MAGL) inhibitor JZL184 have suggested that increased eCB signaling might enhance the ability of the host immune system to clear invading pathogens. Although the neurochemical effects of JZL184 on the eCB system in rodents are well-known, its immuneregulating effects are less clear, especially in chickens. The primary objective of this study was to explore whether modulating the eCB system affects immune responses in chickens. To do this, we administered JZL184 [10 and 40 mg/kg body weight (BW), intraperitoneal injection] into chickens prior to a challenge with avian pathogenic Escherichia coli (APEC) O78. Bacteria were isolated from livers, blood, air sacs, and hearts at 8, 28, and 56 h post-infection and the gross lesions in air sacs, livers, and hearts were also examined. Serum levels of JZL184 were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), which indicated that the drug was distributed systemically. The number of birds positive for airsacculitis after APEC O78 challenge was marginally higher in groups treated with JZL184 than in the control group (P = 0.064). Rather than augmenting host defense and enhancing pathogen clearance, these results suggested that JZL184 might have immunosuppressive effects that exacerbated APEC O78 infection in chickens.
Afficher plus [+] Moins [-]Evaluation of a multipump air pistol as a method for euthanizing young dairy goat kids Texte intégral
2020
Hempstead, Melissa N. | Fowler, Jennifer L. | Shearer, Jane K. | Plummer, Paul J.
OBJECTIVE To assess the extent of damage to the skull and brain of cadaveric dairy goat kids caused by a .22-caliber, 16-g pellet fired from a multipump air pistol at various power levels. SAMPLE Cadavers of 8 male and 7 female dairy goat kids ≤ 5 days old. PROCEDURES Each cadaver was positioned in sternal recumbency with the head and neck extended on a straw bale. A multipump air pistol was held with the barrel perpendicular to and 2.5 cm from the head at the intersection of 2 imaginary lines that extended from the lateral canthus of each eye to the middle of the contralateral ear base and fired at half (5 pumps; n = 2), intermediate (7 pumps; 2), or full (10 pumps; 11) power. The head and neck were removed from the carcass for CT imaging and gross sectioning to determine the location of the pellet and extent of damage caused to the skull and brain. RESULTS The pellet successfully penetrated the skull of all 13 heads shot at full or intermediate power and 1 of the 2 heads shot at half power. The pellet did not fragment after entering the skull of any cadaver and penetrated the brainstem (necessary for instantaneous death) in only 7 cadavers. CONCLUSIONS AND CLINICAL RELEVANCE The described technique was insufficient for use as a stand-alone method for euthanizing young dairy goat kids. Modification of the technique warrants further research to determine whether air pistols can be used to effectively euthanize young goat kids.
Afficher plus [+] Moins [-]Effectiveness of MB-102, a novel fluorescent tracer agent, for conducting ocular angiography in dogs Texte intégral
2020
Pirie, Christopher G. | Rogers, Thomas E. | Dorshow, Richard B.
OBJECTIVE To evaluate the effectiveness of a novel fluorescence tracer agent, MB-102, for conducting ocular angiography in dogs. ANIMALS 10 ophthalmologically normal dogs (2 to 4 years old) and 10 dogs with retinal degeneration or primary open-angle glaucoma (< 6 years old). PROCEDURES While anesthetized, all dogs received sodium fluorescein (20 mg/kg, IV) or MB-102 (20 or 40 mg/kg, IV) first and then the other dye in a second treatment session 2 days later in a randomized crossover design. Anterior fluorescence angiography was performed on one eye and posterior fluorescence angiography on the other. Imaging was performed with a full-spectrum camera and camera adaptor system. Filter sets that were tailored to match the excitation and emission characteristics of each angiographic fluorescent agent were used. RESULTS All phases and phase intervals during anterior and posterior segment angiography were identified, regardless of the dye used. However, agent fluorescence and visualization of the iridal blood vessels were hindered in some dogs, irrespective of agent, owing to the degree of iridal pigmentation present. No significant difference was noted between the 2 dyes in any phase or phase interval, and slight improvement in image contrast was observed with MB-102 during the venous phases owing to a reduction of vessel wall staining in both normal and diseased eyes. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that MB-102 would be useful for conducting ocular angiography in dogs.
Afficher plus [+] Moins [-]Effects of imidazoline and nonimidazoline α-adrenoceptor agonists and antagonists, including xylazine, medetomidine, dexmedetomidine, yohimbine, and atipamezole, on aggregation of feline platelets Texte intégral
2020
Matsukawa, Takuya | Hikasa, Yoshiaki
OBJECTIVE To examine the effects of imidazoline and nonimidazoline α-adrenergic agents on aggregation of feline platelets. SAMPLE Blood samples from 12 healthy adult cats. PROCEDURES In 7 experiments, the effects of 23 imidazoline and nonimidazoline α-adrenoceptor agonists or antagonists on aggregation and antiaggregation of feline platelets were determined via a turbidimetric method. Collagen and ADP were used to initiate aggregation. RESULTS Platelet aggregation was not induced by α-adrenoceptor agonists alone. Adrenaline and noradrenaline induced a dose-dependent potentiation of ADP- or collagen-induced aggregation. Oxymetazoline and xylometazoline also induced a small potentiation of ADP-stimulated aggregation, but other α-adrenoceptor agonists did not induce potentiation. The α2-adrenoceptor antagonists and certain imidazoline α-adrenergic agents including phentolamine, yohimbine, atipamezole, clonidine, medetomidine, and dexmedetomidine inhibited adrenaline-potentiated aggregation induced by ADP or collagen in a dose-dependent manner. The imidazoline compound antazoline inhibited adrenaline-potentiated aggregation in a dose-dependent manner. Conversely, α1-adrenoceptor antagonists and nonimidazoline α-adrenergic agents including xylazine and prazosin were ineffective or less effective for inhibiting adrenaline-potentiated aggregation. Moxonidine also was ineffective for inhibiting adrenaline-potentiated aggregation induced by collagen. Medetomidine and xylazine did not reverse the inhibitory effect of atipamezole and yohimbine on adrenaline-potentiated aggregation. CONCLUSIONS AND CLINICAL RELEVANCE Adrenaline-potentiated aggregation of feline platelets may be mediated by α2-adrenoceptors, whereas imidazoline agents may inhibit in vitro platelet aggregation via imidazoline receptors. Imidazoline α-adrenergic agents may have clinical use for conditions in which there is platelet reactivity to adrenaline. Xylazine, medetomidine, and dexmedetomidine may be used clinically in cats with minimal concerns for adverse effects on platelet function.
Afficher plus [+] Moins [-]Comparison of the use of a vessel-sealing device versus ligatures for occlusion of uterine tissues during ovariohysterectomy or ovariectomy in rabbits (Oryctolagus cuniculus) Texte intégral
2020
McLean, Euan J. | Woodward, Andrew P. | Ryan, Stewart D.
OBJECTIVE To compare the bursting strength of the uterine horns (UHs) and cervical-vestibule junction (CVJs) of rabbits following sealing with a vessel-sealing device (VSD) or encircling ligatures. SAMPLE UHs and CVJs collected from 30 rabbit (Oryctolagus cuniculus) cadavers. PROCEDURES UHs and CVJs were randomly assigned to sealing with encircling Miller knot ligatures (LIG; n = 10 CVJs and 20 UHs) or a VSD (12 CVJs and 24 UHs). Lumens were infused with saline (0.9% NaCl) solution under pressure until seals burst or to a maximum pressure of 300 mm Hg. RESULTS For CVJs, median (range) bursting pressure of the LIG and VSD groups was > 300 mm Hg (224 to > 300 mm Hg) and 35 mm Hg (0 to 60 mm Hg), respectively. Five of 12 CVJs in the VSD group failed at pressures < 33 mm Hg. For UHs, median (range) bursting pressure of the LIG and VSD groups was 255 mm Hg (120 to > 300 mm Hg) and 154 mm Hg (range, 44 to 202 mm Hg), respectively. CONCLUSION AND CLINICAL RELEVANCE The evaluated VSD was effective in sealing UHs at bursting pressures well in excess of expected physiologic pressures, indicating that the VSD may be useful for ovariectomy procedures in rabbits. However, CVJ seals created with the VSD were ineffective and could potentially burst at low pressures, which could predispose to urine entering the abdomen. Given these results, we do not recommend sealing of the CVJ with a VSD for ovariohysterectomy in rabbits.
Afficher plus [+] Moins [-]Investigation of the effects of an ultraviolet germicidal irradiation system on concentrations of aerosolized surrogates for common veterinary pathogens Texte intégral
2020
Pearce-Walker, Jennifer I. | Troup, Daniel J. | Streeter, Rebecca Ives | Ikner, Luisa A. | Rose, Joan B. | Kennedy, Melissa A. | Verhougstraete, Marc P.
OBJECTIVE To determine whether exposure to UV germicidal irradiation (UVGI) reduces concentrations of viable aerosolized microorganisms (attenuated strains of common veterinary pathogens) in a simulated heating, ventilation, and air conditioning (HVAC) system. SAMPLE 42 air samples seeded with bacteriophage MS2 or attenuated strains of Bordetella bronchiseptica, feline calicivirus, feline herpesvirus-1, canine parvovirus, or canine distemper virus (6/microorganism) or with no microorganisms added (6). PROCEDURES A simulated HVAC unit was built that included a nebulizer to aerosolize microorganisms suspended in phosphate-buffered water, a fan to produce airflow, 2 UVGI bulb systems, and an impinger for air sampling. Ten-minute trials (3 with UVGI, 3 without UVGI, and 1 negative control) were conducted for each microorganism. Impingers collected microorganisms into phosphate-buffered water for subsequent quantification with culture-based assays. Results for samples yielding no target microorganisms were recorded as the assay's lower limit of detection. Statistical analysis was not performed. RESULTS The UVGI treatment resulted in subjectively lower concentrations of viable MS2, B bronchiseptica, and canine distemper virus (arithmetic mean ± SD log10 microorganism reduction, 2.57 ± 0.47, ≥ 3.45 ± 0.24, and ≥ 1.50 ± 0.25, respectively) collected from air. Feline herpesvirus-1 was detected in only 1 sample without and no samples with UVGI treatment. Feline calicivirus and canine parvovirus were not detectable in any collected samples. CONCLUSIONS AND CLINICAL RELEVANCE Results for some surrogates of veterinary pathogens suggested a potential benefit to supplementing manual disinfection practices with UVGI-based air cleaning systems in animal care environments. Further research is needed to investigate the utility of UVGI in operating HVAC systems.
Afficher plus [+] Moins [-]Comparative study of the virulence of 3 major Korean porcine circovirus type 2 genotypes (a, b, and d) Texte intégral
2020
Cho, Hyejean | Kang, Ikaje | Oh, Taehwan | Yang, Siyeon | Park, Kee Hwan | Min, Kyung-Duk | Ham, Hee Jin | Chae, Chanhee
The objective of this study was to compare the virulence of 3 major Korean porcine circovirus type 2 (PCV2) genotypes in terms of clinical signs, PCV2 viremia and antibody titers, lymphoid lesions, and PCV2-antigen within lymphoid lesions in experimentally infected pigs. Pigs were infected at 7 weeks with PCV2a, PCV2b, and PCV2d strains and necropsied at 28 days post-infection. No statistical differences were observed in clinical signs, PCV2 viremia and antibody titers, lymphoid lesions scores, and numbers of PCV2 antigens among the 3 major Korean PCV2 genotypes. The results of this study indicate that the 3 major Korean PCV2 genotypes, PCV2a, PCV2b, and PCV2d, have similar virulence.
Afficher plus [+] Moins [-]Effects of treatment with lispro and neutral protamine Hagedorn insulins on serum fructosamine and postprandial blood glucose concentrations in dogs with clinically well-controlled diabetes mellitus and postprandial hyperglycemia Texte intégral
2020
Bertalan, Abigail V. | Drobatz, Kenneth J. | Hess, Rebecka S.
OBJECTIVE To assess effects of basal-bolus insulin treatment (BBIT) with lispro and neutral protamine Hagedorn (NPH) insulins, compared with NPH insulin alone, on serum fructosamine concentration (SFC) and postprandial blood glucose concentration (BGC) in dogs with clinically well-controlled diabetes mellitus and postprandial hyperglycemia fed a high insoluble fiber–content diet. ANIMALS 6 client-owned dogs with diabetes mellitus. PROCEDURES Blood samples were collected for BGC and SFC measurement in hospitalized dogs just before feeding and routine SC NPH insulin administration (time 0); samples were collected for BGC measurement every 30 minutes for 2 hours, then every 2 hours for up to 10 additional hours. Postprandial hyperglycemia was identified when BGC 30 minutes after insulin administration exceeded BGC at time 0 or the 1-hour time point. For BBIT, owners were instructed to continue NPH insulin administration at the usual dosage at home (q 12 h, with feeding) and to administer lispro insulin (0.1 U/Kg, SC) separately at the time of NPH injections. Two weeks later, SFC and BGC measurements were repeated; results at the start and end of the study were compared statistically. RESULTS Median SFC was significantly higher at the start (400 μmol/L) than at the end (390 μmol/L) of the study. Median 1-hour (313 mg/dL) and 1.5-hour (239 mg/dL) BGC measurements at the start of the study were significantly higher than those at the end of the study (117 and 94 mg/dL, respectively). CONCLUSIONS AND CLINICAL RELEVANCE In this sample of dogs with well-controlled diabetes mellitus, addition of lispro insulin to an existing treatment regimen of NPH insulin and dietary management significantly decreased postprandial BGCs. Further study of BBIT for dogs with diabetes mellitus is warranted.
Afficher plus [+] Moins [-]Pharmacokinetics of amantadine after oral administration of single and multiple doses to orange-winged Amazon parrots (Amazona amazonica) Texte intégral
2020
Berg, Kyra J. | Sanchez-Migallon Guzman, David | Knych, Heather K. | Drazenovich, Tracy L. | Paul-Murphy, Joanne R.
OBJECTIVE To determine the pharmacokinetics of amantadine after oral administration of single and multiple doses to orange-winged Amazon parrots (Amazona amazonica). ANIMALS 12 adult orange-winged Amazon parrots (6 males and 6 females). PROCEDURES A single dose of amantadine was orally administered to 6 birds at 5 mg/kg (n = 2), 10 mg/kg (2), and 20 mg/kg (2) in a preliminary trial. On the basis of the results, a single dose of amantadine (10 mg/kg, PO) was administered to 6 other birds. Two months later, multiple doses of amantadine (5 mg/kg, PO, q 24 h for 7 days) were administered to 8 birds. Heart rate, respiratory rate, behavior, and urofeces were monitored. Plasma concentrations of amantadine were measured via tandem liquid chromatography–mass spectrometry. Pharmacokinetic parameter estimates were determined via noncompartmental analysis. RESULTS Mean ± SD maximum plasma concentration, time to maximum plasma concentration, half-life, and area under the concentration-versus-time curve from the last dose to infinity were 1,174 ± 186 ng/mL, 3.8 ± 1.8 hours, 23.2 ± 2.9 hours, and 38.6 ± 7.4 μg·h/mL, respectively, after a single dose and 1,185 ± 270 ng/mL, 3.0 ± 2.4 hours, 21.5 ± 5.3 hours, and 26.3 ± 5.7 μg·h/mL, respectively, at steady state after multiple doses. No adverse effects were observed. CONCLUSIONS AND CLINICAL RELEVANCE Once-daily oral administration of amantadine at 5 mg/kg to orange-winged Amazon parrots maintained plasma concentrations above those considered to be therapeutic in dogs. Further studies evaluating safety and efficacy of amantadine in orange-winged Amazon parrots are warranted.
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