The objective of this study was to evaluate the association between ketonemia and serum paraoxonase-1 (PON1), malondialdehyde (MDA), and other blood components in tail and mammary veins of dairy cows. Forty-two Holstein dairy cows with decreased feed intake were divided into HIGH (≥ 1.2 mM; n = 31) and LOW (< 1.2 mM; n = 11) groups based on the β-hydroxybutyrate concentration in plasma collected from the tail vein. The HIGH group had a significantly greater plasma non-esterified fatty acid (NEFA) concentration, but significantly lower serum PON1 activity and phospholipid concentration, and a tendency to have a lower cholesterol ester concentration than the LOW group. Serum PON1 activity was not correlated with the MDA concentration but was positively correlated with serum concentrations of cholesterol esters and phospholipids, and negatively correlated with the plasma NEFA concentration. These results suggest that serum PON1 activity is reduced by hyperketonemia and the relevance of PON1 to MDA seems to not be direct, though it is involved.

OBJECTIVE To evaluate the feasibility of contrast-enhanced CT for assessment of pancreatic perfusion in healthy dogs. ANIMALS 6 healthy purpose-bred female Treeing Walker Coonhounds. PROCEDURES Contrast-enhanced CT of the cranial part of the abdomen was performed with 3-mm slice thickness. Postprocessing computer software designed for evaluation of human patients was used to calculate perfusion data for the pancreas and liver by use of 3-mm and reformatted 6-mm slices. Differences in perfusion variables between the pancreas and liver and differences in liver-specific data of interest were evaluated with the Friedman test. RESULTS Multiple pancreatic perfusion variables were determined, including perfusion, peak enhancement index, time to peak enhancement, and blood volume. The same variables as well as arterial, portal, and total perfusion and hepatic perfusion index were determined for the liver. Values for 6-mm slices appeared similar to those for 3-mm slices. The liver had significantly greater median perfusion and peak enhancement index, compared with the pancreas. CONCLUSIONS AND CLINICAL RELEVANCE Measurement of pancreatic perfusion with contrast-enhanced CT was feasible in this group of dogs. Hepatic arterial and pancreatic perfusion values were similar to previously published findings for dogs, but hepatic portal and hepatic total perfusion measurements were not. These discrepancies might have been attributable to physiologic differences between dogs and people and related limitations of the CT software intended for evaluation of human patients. Further research is warranted to assess reliability of perfusion variables and applicability of the method for assessment of canine patients with pancreatic abnormalities.

Concentrations of 64% to 70% nitrous oxide (N(2)O) provide intra-operative analgesia. Clinically, pulse oximeter estimation (SpO(2)) of oxygen (O(2)) hemoglobin saturation (SaO(2)) was observed to decrease with N2O. Absorption atelectasis from breathing O2 was thought to decrease arterial partial pressure of O2 (PaO(2)) below 70 mmHg and reduce SaO(2) and SpO(2) when N(2)O was used. Administering N(2)O from the beginning of the anesthesia might prevent atelectasis development and low PaO(2).The study was done in 2 parts (P, 0.05). In Part 1, isoflurane-anesthetized dogs undergoing ovariohysterectomy (n = 15 each group) breathed N(2)O from anesthesia start (N(2)O early) or 1 hour later (N2Olate). SpO(2), CO-oximetry values, and PaO(2) were compared to dogs breathing O(2) throughout anesthesia (control). Timing of N(2)O introduction did not affect PaO(2) (lowest = 94 mmHg), SaO(2), or SpO(2). With N(2)O, the lowest SpO(2) value was 91% and corresponded to a PaO2 of 151 mmHg. Carboxyhemoglobin increased (highest = 2.7%) and SaO(2) decreased with N2O (lowest = 96.7%). In Part 2, to replicate findings, 10 isoflurane-anesthetized dogs breathed N(2)O, then O(2). With N2O, SaO2 did not decrease, but carboxyhemoglobin increased and returned to baseline once N2O was discontinued. The dog with the highest carboxyhemoglobin (2%) had an SaO(2) of 96.8% (PaO(2) = 93 mmHg). Carboxyhemoglobin and SaO(2) changes were not clinically significant. Pulse oximetry did not reliably estimate SaO(2) but N(2)O was not always a factor.

OBJECTIVE To evaluate the effects of 3 electrolyte solutions administered SC to experimentally dehydrated inland bearded dragons (Pogona vitticeps). ANIMALS 9 inland bearded dragons. PROCEDURES In a randomized, complete crossover study, experimental dehydration was induced by means of furosemide (10 mg/kg, SC, q 12 h for 4 doses), and then lactated Ringer solution, Plasma-Lyte A, or reptile Ringer solution (RRS; 1:1 mixture of 5% dextrose solution and isotonic crystalloid solution) was administered SC in a single 50-mL/kg dose in 3 treatments sessions separated by a minimum of 14 days. Food and water were withheld during treatment sessions. Plasma biochemical values, PCV, blood total solids and lactate concentrations, and plasma osmolarity were measured prior to (baseline) and 4 and 24 hours after fluid administration. RESULTS Administration of RRS resulted in severe hyperglycemia (mean ± SD plasma glucose concentration, 420 ± 62 mg/dL), compared with baseline values (190 ± 32 mg/dL), and this hyperglycemia persisted for at least 24 hours. It also resulted in significant reductions in plasma osmolarity and sodium and phosphorus concentrations, which were not observed after administration of the other 2 solutions. Administration of lactated Ringer solution caused no significant increase in blood lactate concentration. CONCLUSIONS AND CLINICAL RELEVANCE The changes in plasma glucose, sodium, and phosphorus concentrations and plasma osmolarity observed after SC administration of a single dose of RRS suggested this type of electrolyte solution should not be used for rehydration of bearded dragons. Rather, lactated Ringer solution or Plasma-Lyte A should be considered instead.

OBJECTIVE To characterize the patterns associated with Lorenz plots (LPs) or Poincaré plots derived from the Holter recordings of dogs with various cardiac rhythms. ANIMALS 77 dogs with 24-hour Holter recordings. PROCEDURES A 1-hour period from the Holter recordings from each of 20 dogs without arrhythmias and from each of 57 dogs with arrhythmias (10 each with supraventricular premature complexes, complex supraventricular ectopy, ventricular premature complexes, complex ventricular ectopy, and atrial fibrillation, and 7 with high-grade second-degree atrioventricular block) were used to generate the LPs. Patterns depicted in the LPs were described. RESULTS Arrhythmia-free Holter recordings yielded LPs with a Y-shaped pattern and variable silent zones. Recordings with single premature complexes yielded LPs with double side and triple side lobes. Complex ectopy was denoted by dots clustered in the lower left corner of the LPs. The LPs of recordings with atrial fibrillation had fan patterns consistent with a nonlinear relationship between atrial electrical impulses and atrioventricular nodal conduction. The recordings with atrioventricular block yielded LPs with island patterns consistent with variable atrioventricular nodal conduction. CONCLUSIONS AND CLINICAL RELEVANCE Distinct LP patterns were identified for common cardiac rhythms of dogs, supportive of nonrandom mechanisms as the cause of most rhythms. Visual interpretation of an LP generated from a Holter recording may aid in determining the arrhythmia type and understanding the arrhythmia's mechanism in dogs and other species.

OBJECTIVE To determine whether jejunal serosal patches could securely seal large, open defects in duodenal segments harvested from canine cadavers and to compare intraluminal pressures at which leakage first occurred and maximal intraluminal pressures for repaired duodenal segments between 2 suture patterns. SAMPLE Duodenal and jejunal segments from 9 canine cadavers. PROCEDURES 20 constructs were created through repair of large, open duodenal defects with circumferential suturing of an intact jejunal segment (jejunal serosal patch). Constructs were randomly assigned to have the serosal patch anastomosed to the duodenal segment by a simple continuous or simple interrupted suture pattern. The pressure at which the first leakage was observed and the maximum pressure obtained during testing were recorded and compared between suture patterns. RESULTS Initial leakage pressure was significantly higher with the simple interrupted pattern (mean ± SD, 68.89 ± 5.62 mm Hg), compared with the simple continuous pattern (59.8 ± 20.03 mm Hg). Maximum intraluminal pressures did not significantly differ between the simple interrupted (91 ± 8.27 mm Hg) and simple continuous patterns (90.7 ± 16.91 mm Hg). All constructs, regardless of suture pattern, withstood supraphysiologic pressures. CONCLUSIONS AND CLINICAL RELEVANCE Jejunal serosal patches adequately sealed large, open duodenal defects and prevented leakage in these constructs. Constructs with simple continuous or simple interrupted suture patterns withstood physiologic and supraphysiologic intraluminal pressures, although constructs with a simple interrupted suture pattern initially leaked at higher pressures.

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.

Immunohistochemistry has been used extensively to evaluate protein expression in clinical and research settings. However, immunohistochemistry is not always successful in veterinary medicine due to the lack of reliable antibody options, poor tissue preservation, labor-intensive staining, and antigen-retrieval optimization processes. RNAscope in-situ hybridization (ISH) is a powerful technology that uses a specific sequence probe to identify targeted mRNA. In this study, we demonstrate RNAscope ISH in 4 common canine malignancies, which are traditionally diagnosed by histopathology and immunohistochemistry. Probes were designed for commonly targeted mRNA markers of neoplastic tumors; these included c-kit in mast cell tumor, microphthalmia-associated transcription factor in malignant melanoma, ionized calcium-binding adapter molecule(-1) in histiocytic sarcoma, and alkaline phosphatase in osteosarcoma. A strong staining signal was obtained by these 4 targets in each canine malignancy. These results support the use of RNAscope ISH for definitive diagnosis in canine malignancies.

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.

OBJECTIVE To compare load-to-failure results for laparoscopic absorbable fixation straps (AFSs) deployed at various angles and for AFSs versus absorbable knotless (barbed) suture when used in simulated total laparoscopic gastropexy (TLG) in specimens from cadaveric dogs. SAMPLE 30 stomach and abdominal body wall specimens. PROCEDURES Specimens were assigned to 1 of 3 groups for use in simulated TLG constructs for comparisons of load-to-failure results for single AFSs deployed at 30°, 60°, or 90° (AFS-angle group; n = 10) or for a gastropexy span of 4 to 5 cm achieved with 3-0 absorbable knotless (barbed) monofilament suture applied in a simple continuous pattern (TLG-1; 10) versus 8 AFSs applied with a deployment angle > 30° (TLG-2; 10). A 1-way ANOVA was used to compare results among AFS deployment angles (30°, 60°, or 90°) and between TLG-1 and TLG-2. RESULTS Mean ± SD load to failure for the AFS-angle group was significantly higher for the AFS deployment angles of 60° (8.00 ± 3.90 N) and 90° (12.71 ± 8.00 N), compared with 30° (5.17 ± 1.90 N). However, no substantial difference was detected in the mean ± SD load to failure for TLG-1 (39.18 ± 7.1 N) versus TLG-2 (31.43 ± 10.86 N). CONCLUSIONS AND CLINICAL RELEVANCE Results of the present study supported the potential use of AFSs in gastropexy in dogs; however, prospective clinical research with adequate long-term follow-up is warranted before recommendations can be made.