OBJECTIVE To compare security of continuous intradermal suture lines closed by use of barbed suture with 3 end-pass configurations or without an end-pass configuration. SAMPLE 40 full-thickness, 4-cm-long, parasagittal wounds in canine cadavers. PROCEDURES Each continuous intradermal closure was terminated with 1 of 3 end-pass techniques or without an end-pass configuration (control group). A servohydraulic machine applied tensile load perpendicular to the long axis of the suture line. A load-displacement curve was generated for each sample; maximum load, displacement, stiffness, mode of construct failure, and load at first suture slippage at termination (ie, terminal end of the suture line) were recorded. RESULTS Values for maximum load, displacement, and stiffness did not differ significantly among the 3 end-pass techniques, and load at first suture slippage at termination was not significantly different among the 4 groups. A 1-pass technique slipped in 5 of 9 samples; 3 of these 5 slips caused failure of wound closure. A 2-pass technique slipped in 3 of 9 samples, none of which caused failure of wound closure. Another 2-pass technique slipped in 4 of 10 samples; 2 of these 4 slips caused failure of wound closure. The control group had slippage in 10 of 10 samples; 9 of 10 slips caused failure of wound closure CONCLUSIONS AND CLINICAL RELEVANCE An end-pass anchor was necessary to terminate a continuous intradermal suture line, and all 3 end-pass anchor techniques were suitable to prevent wound disruption. The 2-pass technique for which none of the suture slippages caused wound closure failure provided the most reliable configuration.

OBJECTIVE To describe plasma pharmacokinetic parameters and tissue elimination of flunixin in veal calves. ANIMALS 20 unweaned Holstein calves between 3 and 6 weeks old. PROCEDURES Each calf received flunixin (2.2 mg/kg, IV, q 24 h) for 3 days. Blood samples were collected from all calves before the first dose and at predetermined times after the first and last doses. Beginning 24 hours after injection of the last dose, 4 calves were euthanized each day for 5 days. Plasma and tissue samples were analyzed by ultraperformance liquid chromatography. Pharmacokinetic parameters were calculated by compartmental and noncompartmental methods. RESULTS Mean ± SD plasma flunixin elimination half-life, residence time, and clearance were 1.32 ± 0.94 hours, 12.54 ± 10.96 hours, and 64.6 ± 40.7 mL/h/kg, respectively. Mean hepatic and muscle flunixin concentrations decreased to below FDA-established tolerance limits (0.125 and 0.025 μg/mL, respectively) for adult cattle by 3 and 2 days, respectively, after injection of the last dose of flunixin. Detectable flunixin concentrations were present in both the liver and muscle for at least 5 days after injection of the last dose. CONCLUSIONS AND CLINICAL RELEVANCE The labeled slaughter withdrawal interval for flunixin in adult cattle is 4 days. Because administration of flunixin to veal calves represents extralabel drug use, any detectable flunixin concentrations in edible tissues are considered a violation. Results indicated that a slaughter withdrawal interval of several weeks may be necessary to ensure that violative tissue residues of flunixin are not detected in veal calves treated with that drug.

OBJECTIVE To determine the ultrasonographic appearance of the major duodenal papilla (MDP) in dogs without evidence of hepatobiliary, pancreatic, or gastrointestinal tract disease.ANIMALS 40 adult client-owned dogs examined because of conditions that did not include hepatobiliary, pancreatic, or gastrointestinal tract disease. PROCEDURES Ultrasonographic examination of the MDP was performed. Each MDP was measured in 3 planes. Intraobserver reliability of measurements was determined, and associations between MDP dimensions and characteristics of the dogs were investigated. Histologic examination of longitudinal sections of the MDP was performed for 1 dog to compare the ultrasonographic and histologic appearance. RESULTS The MDP appeared as a layered structure with a hyperechoic outer layer, hypoechoic middle layer, and hyperechoic inner layer that corresponded to the duodenal serosa, duodenal muscularis, and duodenal submucosa, respectively. Layers visible during ultrasonographic examinations were consistent with layers identified histologically. Intraobserver reliability was substantial for each plane of measurement. Mean ± SD length, width, and height of the MDP were 15.2 ± 3.5 mm, 6.3 ± 1.6 mm, and 4.3 ± 1.0 mm, respectively. An increase in body weight of dogs was significantly associated with increased values for all measurements. CONCLUSIONS AND CLINICAL RELEVANCE The ultrasonographic appearance and approximate dimensions of the MDP of dogs without evidence of hepatobiliary, pancreatic, or gastrointestinal tract disease were determined. Additional studies are needed to evaluate possible ultrasonographic lesions of the MDP in dogs with hepatobiliary, pancreatic, or intestinal diseases and to investigate clinical implications of these lesions with regard to diagnosis and prognosis.

OBJECTIVE To characterize the extent and location of atelectasis in healthy anesthetized dogs positioned in lateral recumbency and to determine whether repositioning dogs in sternal recumbency would resolve atelectasis. ANIMALS 6 healthy adult Beagles. PROCEDURES Each dog was anesthetized and underwent a CT examination twice with a 2-week interval between examinations. Once anesthetized, each dog was positioned in sternal recumbency, and a breath-hold helical transverse thoracic CT scan was acquired. The dog was then positioned in lateral recumbency for 30 minutes, and images were obtained at 5 preselected sites at 3, 8, 13, 20, and 30 minutes after repositioning (phase 1). Then, the dog was repositioned in sternal recumbency, and CT images were obtained at the 5 preselected sites at 5, 10, and 20 minutes after repositioning (phase 2). The protocol for the second examination was the same as the first except the dog was positioned in the opposite lateral recumbency during phase 1. The attenuation and cross-sectional area of the lung lobes at the preselected sites were measured and compared over time. RESULTS Lateral recumbency did not cause atelectasis in any of the dogs. Patchy areas of abnormally increased attenuation were infrequently detected in the left cranial lung lobe when dogs were positioned in left lateral recumbency, and those areas failed to resolve when dogs were positioned in sternal recumbency. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the extent of lung attenuation changes was minimal in healthy anesthetized Beagles positioned in lateral recumbency and should not preclude CT examination.

OBJECTIVE To assess the pharmacokinetic properties of cefovecin in a cold-water teleost species. ANIMALS 10 healthy adult copper rockfish (Sebastes caurinus), sex unknown. PROCEDURES Cefovecin (16 mg/kg) was administered SC to the rockfish. Blood samples were collected at predetermined points for measurement of plasma cefovecin concentrations (3 samples/fish). Plasma cefovecin concentrations were measured via liquid chromatography with mass spectrometry. Pharmacokinetic analysis was performed by means of naïve pooled analysis and compartmental modeling. Plasma protein binding of cefovecin was determined by ultrafiltration. RESULTS Cefovecin administration appeared to be well tolerated by the rockfish. Pharmacokinetic analysis resulted in a maximum plasma concentration of 104.8 μg/mL at 2.07 hours after administration. Plasma terminal half-life was 32.5 hours, and area under the curve was 5,132 h·g/mL. Plasma protein binding was low (< 10%) for plasma concentrations of 10 and 100 μg of cefovecin/mL when assessed at 7.8° and 20°C. Plasma concentrations > 1 μg/mL persisted for the full 7-day follow-up period. CONCLUSIONS AND CLINICAL RELEVANCE SC administration of cefovecin to copper rockfish at a dose of 16 mg/kg yielded plasma concentrations > 1 μg/mL that persisted to 7 days, but some interindividual variability was observed. The low degree of plasma protein binding but high circulating concentration of free drug may allow an extended administration interval in rockfish. Studies are needed to assess the efficacy and safety of this dose in rockfish.

OBJECTIVE To determine pharmacodynamic and pharmacokinetic profiles of aminocaproic acid (ACA) by use of a thromboelastography (TEG)-based in vitro model of hyperfibrinolysis and high-performance liquid chromatography–mass spectrometry. ANIMALS 5 healthy adult dogs. PROCEDURES A single dose of injectable ACA (20, 50, or 100 mg/kg) or an ACA tablet (approximately 100 mg/kg) was administered orally. Blood samples were collected at 0, 15, 30, 45, 60, 90, 120, and 240 minutes after ACA administration for pharmacokinetic analysis. Samples were obtained at 0, 60, and 240 minutes for pharmacodynamic analysis by use of a TEG model of hyperfibrinolysis. RESULTS No adverse effects were detected. In the hyperfibrinolysis model, after all doses, a significantly higher TEG maximum amplitude (clot strength), compared with baseline, was detected at 60 and 240 minutes. Additionally, the percentage of fibrinolysis was reduced from the baseline value at 60 and 240 minutes, with the greatest reduction at 60 minutes. At 240 minutes, there was significantly less fibrinolysis for the 100 mg/kg dose than the 20 mg/kg dose. Maximum plasma ACA concentration was dose dependent. There was no significant difference in pharmacokinetic parameters between 100 mg/kg formulations. CONCLUSIONS AND CLINICAL RELEVANCE In an in vitro model of hyperfibrinolysis, ACA inhibited fibrinolysis at all doses tested. At 240 minutes after administration, the 100 mg/kg dose inhibited fibrinolysis more effectively than did the 20 mg/kg dose. Thus, ACA may be useful for in vivo prevention of fibrinolysis in dogs. IMPACT FOR HUMAN MEDICINE These data may improve research models of hyperfibrinolytic diseases.

OBJECTIVE To identify and evaluate 3 types of angiographic catheters for retrograde urinary bladder catheterization in healthy male goats. ANIMALS 12 sexually intact yearling Alpine-cross bucks. PROCEDURES Three 5F angiographic catheters of the same length (100 cm) and diameter (0.17 cm) but differing in curvature at the tip were labeled A (straight tip), B (tip bent in 1 place), and C (tip bent in 2 places). During a single anesthetic episode, attempts were made to blindly pass each catheter into the urinary bladder of each goat. Order of catheters used was randomized, and the veterinarian passing the catheter was blinded as to catheter identity. The total number of attempts at catheter passage and the total number of successful attempts were recorded. RESULTS Catheter A was unsuccessfully passed in all 12 goats, catheter B was successfully passed in 8 goats, and catheter C was successfully passed in 4 goats. The success rate for catheter B was significantly greater than that for catheter A; however, no significant difference was identified between catheters B and C or catheters A and C. CONCLUSIONS AND CLINICAL RELEVANCE 2 angiographic catheters were identified that could be successfully, blindly advanced in a retrograde direction into the urinary bladder of healthy sexually intact male goats. Such catheters may be useful for determining urethral patency, emptying the urinary bladder, and instilling chemolysing agents in goats with clinical obstructive urolithiasis.

OBJECTIVE To investigate the in vitro stability of atrial natriuretic peptide (ANP) in plasma samples under various storage conditions and the influence of anesthesia on plasma ANP concentration in cats. ANIMALS 1 cat with congestive heart failure and 5 healthy adult mixed-breed cats. PROCEDURES A plasma sample from the cat with heart failure was serially diluted, and dilutional parallelism of ANP concentration was evaluated. Plasma samples containing aprotinin or serum samples from the 5 healthy cats were kept at room temperature (27°C) for ≤ 12 hours. Plasma samples from the same healthy cats were stored at −70°, −20°, or 4°C for ≤ 14 days. Plasma samples were obtained from the healthy cats before and during isoflurane anesthesia. Plasma ANP concentrations were measured at a commercial laboratory by use of a human ANP chemiluminescence assay. RESULTS Intra- and interassay coefficients of variation were 1.5% and 2.5%, respectively, and dilutional parallelism was established. Although ANP concentration decreased by 82.4 ± 13.6% (mean ± SD) after sample storage for 12 hours at room temperature, this decrease was prevented by aprotinin. Plasma ANP concentrations were stable for 7 days at −20°C and for 14 days at −70°C. However, concentrations decreased markedly to 57.6 ± 6.9% at −20°C and to 18.0 ± 3.0% at 4°C after 14 days. Plasma ANP concentration decreased significantly in cats during anesthesia and was correlated with blood pressure. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that aprotinin should be added routinely in preparation of plasma samples from cats for measurement of ANP concentration, and those samples, if stored, should be frozen immediately at ≤ −20°C. General anesthesia or systemic blood pressure may affect plasma ANP concentration in cats.

OBJECTIVE To determine the locomotor response to the administration of fentanyl in horses with and without the G57C polymorphism of the μ-opioid receptor. ANIMALS 20 horses of various breeds and ages (10 horses heterozygous for the G57C polymorphism and 10 age-, breed-, and sex-matched horses that did not have the G57C polymorphism). PROCEDURES The number of steps each horse took was counted over consecutive 2-minute periods for 20 minutes to determine a baseline value. The horse then received a bolus of fentanyl (20 μg/kg, IV), and the number of steps was again counted during consecutive 2-minute periods for 60 minutes. The mean baseline value was subtracted from each 2-minute period after fentanyl administration; step counts with negative values were assigned a value of 0. Data were analyzed by use of a repeated-measures ANOVA. RESULTS Data for 19 of 20 horses (10 horses with the G57C polymorphism and 9 control horses without the G57C polymorphism) were included in the analysis. Horses with the G57C polymorphism had a significant increase in locomotor activity, compared with results for horses without the polymorphism. There was a significant group-by-time interaction. CONCLUSIONS AND CLINICAL RELEVANCE Horses heterozygous for the G57C polymorphism of the μ-opioid receptor had an increased locomotor response to fentanyl administration, compared with the response for horses without this polymorphism. The clinical impact of this finding should be investigated.

A cross-sectional study was conducted to assess cattle owners' awareness, perceptions, attitudes and drug-usage practices with regard to bovine dermatophilosis. Knowledge of these farmers' attributes is important for animal health policy makers in their endeavours to provide optimum disease control strategies that are acceptable to the communities. Data on cattle owner awareness of bovine dermatophilosis, causes, treatment practices, perceptions about its importance and potential dangers to humans were collected using an interviewer-administered questionnaire. A total of 185 stockowners and cattle herds were involved in the study, with bovine dermatophilosis determined clinically by veterinarians. The results showed that 45.4% of the herds were clinically positive for dermatophilosis, and most farmers (79.5%) were generally aware that dermatophilosis was a cattle disease. In the event of a dermatophilosis outbreak in a herd, 74.1% of the farmers treated their cattle using antibiotics; the proportion of farmers treating cattle did not differ (p > 0.05) across the diptanks. Fifty-two farmers (52/63) indicated that drugs had to be administered four to seven times before an animal recovered from infection. Tetracyclines were the antibiotics used by most farmers (79.3%) to treat dermatophilosis, with 19.1% using penicillins. Concerns were raised by farmers about the effectiveness of these drugs against bovine dermatophilosis. Across the study sites, 48.6% and 27.6% of the farmers perceived bovine dermatophilosis to be an important disease at the herd and area level, respectively. A small proportion (12.4%) of the farmers regarded bovine dermatophilosis as a potentially zoonotic disease. The high level of stockowners' general awareness, with regards to bovine dermatophilosis, sets ideal conditions for the mobilisation of farmers by animal health authorities in the control of the disease. However, further research needs to be undertaken to investigate effective antibiotic delivery protocols and the potential zoonotic impact of bovine dermatophilosis in a situation of high disease prevalence.