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- Author or Editor: John R. Middleton x
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Abstract
Objective—To determine the prevalence of detectable serum IgG concentrations in calves prior to ingestion of colostrum and to assess whether a detectable IgG concentration was related to dam parity, calf birth weight, calf sex, season of calving, or infectious agents that can be transmitted transplacentally.
Animals—170 Holstein dairy calves.
Procedures—Serum samples were obtained from calves prior to ingestion of colostrum, and serologic testing for bovine viral diarrhea virus (BVDV) and Neospora caninum was performed. Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum and BVDV serologic testing were calculated. Logistic regression analysis was used to determine whether dam parity, calf sex, season of calving, and calf weight were associated with precolostral IgG concentration.
Results—90 (52.9%) calves had a detectable total serum IgG concentration (IgG ≥ 16 mg/dL). Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum serologic testing were 1.66, 0.34, 0.014, and 0.03, respectively. Calf sex, calf birth weight, and season of calving were not significant predictors for detection of serum IgG in precolostral samples.
Conclusions and Clinical Relevance—Prevalence of IgG concentrations in precolostral serum samples was higher than reported elsewhere. There was no apparent link between serum antibodies against common infectious agents that can be transmitted transplacentally and detection of measurable serum IgG concentrations.
Abstract
OBJECTIVE
To evaluate the time and number of laser beam passes required to make full-thickness skin incisions and extent of laser-induced tissue artifacts following use of a CO2 laser at various settings.
SAMPLE
24 skin specimens from six 5-month-old porcine carcasses.
PROCEDURES
4 full-thickness skin specimens were harvested from the flank regions of each carcass within 30 minutes after euthanasia and randomly assigned to 4 treatment groups. Three 5-cm-long incisions were made in each specimen with a CO2 laser (beam diameter, 0.4 mm) set to deliver a continuous wave of energy alone (groups 1 and 2) or in superpulse mode (groups 3 and 4) at 10 (groups 1 and 3) or 20 (groups 2 and 4) W of power. The time and number of passes required to achieve a full-thickness incision were recorded, and extent of laser-induced tissue artifact (as determined by histologic evaluation) was compared among the 4 groups.
RESULTS
Mean time required to make a full-thickness skin incision for groups 2 and 4 (power, 20 W) was significantly less than that for groups 1 and 3 (power, 10 W). Mean number of passes was lowest for group 2 (continuous wave at 20 W). Extent of laser-induced tissue artifact was greatest for group 4 (superpulse mode at 20 W).
CONCLUSIONS AND CLINICAL RELEVANCE
Results provided preliminary information regarding use of CO2 lasers to make skin incisions in veterinary patients. In vivo studies are necessary to evaluate the effect of various CO2 laser settings on tissue healing and patient outcome.
Abstract
Case Description—A 5-year-old castrated male Vietnamese pot-bellied pig (Sus scrofa) was evaluated because of anorexia, vomiting, diarrhea, and weight loss.
Clinical Findings—Hypermotile gastrointestinal sounds were noted on abdominal auscultation. An inflammatory leukogram, dehydration, prerenal azotemia, hyponatremia, hypochloremia, hyperproteinemia, hyperglobulinemia, hypomagnesemia, and high γ-glutamyl transpeptidase activity were identified. Transabdominal ultrasonography revealed distended loops of small intestine.
Treatment—IV fluid therapy and analgesic treatment were unsuccessful in the resolution of clinical signs. Exploratory laparotomy revealed an ileocecal intussusception involving the distal portion of the ileum. Distal ileal and cecal bypass were achieved via side-to-side anastomosis of the proximal portion of the ileum and spiral colon with a gastrointestinal anastomosis stapler. Ileal transection or occlusion was not performed. Postoperative complications were minimal, and the pig was clinically normal 15 months after surgery and required no special care or diet.
Clinical Relevance—Distal ileal and cecal bypass without ileal transection have not been described previously in Vietnamese pot-bellied pigs. Anastomosis of the proximal portion of the ileum to the spiral colon without major complications represents a novel, technically simple approach to bypass of the distal portion of the ileum and cecum.
Abstract
OBJECTIVE To compare the leak pressure and amount of time required to perform closure for 2 double-layer esophagotomy closure techniques.
SAMPLE 28 intrathoracic esophageal segments harvested from 38 porcine cadavers.
PROCEDURES Longitudinal 3-cm esophagotomy incisions made in porcine cadaveric esophagi were closed with 2 double-layer closure techniques. Fifteen incisions were closed with a simple interrupted pattern, and 13 incisions were closed with a simple continuous pattern. Leak pressure, bursting wall tension, and closure time were compared between suture patterns by use of a t test or Mann-Whitney rank sum test.
RESULTS Median leak pressures differed significantly between segments closed with the simple interrupted pattern (16.0 mm Hg; range, 5.4 to 54.9 mm Hg) and the simple continuous pattern (38.7 mm Hg; range, 11.3 to 81.9 mm Hg). Median bursting wall tension differed significantly between the simple interrupted pattern (0.63 × 105 dynes/cm; range, 0.16 × 105 dynes/cm to 2.89 × 105 dynes/cm) and the simple continuous pattern (1.79 × 105 dynes/cm; range, 0.44 × 105 dynes/cm to 4.70 × 105 dynes/cm). Mean ± SD closure time differed significantly between the simple interrupted pattern (19.2 ± 2.0 minutes) and the simple continuous pattern (14.7 ± 1.5 minutes).
CONCLUSIONS AND CLINICAL RELEVANCE In the study reported here, double-layer simple continuous closure resulted in a higher median postoperative leak pressure and higher median postoperative bursting wall tension and could be performed more rapidly than the double-layer simple interrupted closure on these porcine cadaveric specimens.
Abstract
OBJECTIVE To determine whether stored (cooled or frozen-thawed) jejunal segments can be used to obtain dependable leak pressure data after enterotomy closure.
SAMPLE 36 jejunal segments from 3 juvenile pigs.
PROCEDURES Jejunal segments were harvested from euthanized pigs and assigned to 1 of 3 treatment groups (n = 12 segments/group) as follows: fresh (used within 4 hours after collection), cooled (stored overnight at 5°C before use), and frozen-thawed (frozen at −12°C for 8 days and thawed at room temperature [23°C] for 1 hour before use). Jejunal segments were suspended and 2-cm enterotomy incisions were made on the antimesenteric border. Enterotomies were closed with a simple continuous suture pattern. Lactated Ringer solution was infused into each segment until failure at the suture line was detected. Leak pressure was measured by use of a digital transducer.
RESULTS Mean ± SD leak pressure for fresh, cooled, and frozen-thawed segments was 68.3 ± 23.7 mm Hg, 55.3 ± 28.1 mm Hg, and 14.4 ± 14.8 mm Hg, respectively. Overall, there were no significant differences in mean leak pressure among pigs, but a significant difference in mean leak pressure was detected among treatment groups. Mean leak pressure was significantly lower for frozen-thawed segments than for fresh or cooled segments, but mean leak pressure did not differ significantly between fresh and cooled segments.
CONCLUSIONS AND CLINICAL RELEVANCE Fresh porcine jejunal segments or segments cooled overnight may be used for determining intestinal leak pressure, but frozen-thawed segments should not be used.
Abstract
Objective—To compare the efficacy of a lacteal-derived colostrum replacer (LDCR) for the prevention of failure of passive transfer of immunity (FPT) in calves with that of pooled maternal colostrum (MC).
Design—Randomized field trial.
Animals—568 heifer calves from 1 California dairy.
Procedures—Calves were randomly allocated to 1 of 2 treatment groups and fed 2 doses (200 g of IgG) of an LDCR or 3.8 L of pooled MC. From each calf, blood samples were collected before and approximately 24 hours after treatment. Serum IgG and total protein (TP) concentrations were quantified with standard methods, and the apparent efficiency of IgG absorption was calculated.
Results—At 24 hours after treatment, mean serum TP and IgG concentrations were significantly lower for calves fed pooled MC (TP, 4.77 g/dL; IgG, 7.50 g/L), compared with those for calves fed the LDCR (TP, 5.50 g/dL; IgG, 15.15 g/L). Calves fed the LDCR were 95% less likely to develop FPT (OR, 0.05; 95% confidence interval, 0.03 to 0.08) than were calves fed pooled MC. However, the mean IgG concentration in the pooled MC fed during the study (21.1 g/L) was substantially lower than that (64.3 g/L) determined for representative samples of pooled MC from other southwestern US dairies during a national survey.
Conclusions and Clinical Relevance—Results indicated that, on this particular dairy, calves fed an LDCR were at less risk of developing FPT than were calves fed pooled MC. The LDCR evaluated was a viable alternative for the prevention of FPT in calves.
Abstract
Objective—To determine the pharmacokinetic disposition of IV administered caffeine in healthy Lama spp camelids.
Animals—4 adult male alpacas and 4 adult female llamas.
Procedures—Caffeine (3 mg/kg) was administered as an IV bolus. Plasma caffeine concentrations were determined by use of high-performance liquid chromatography in 6 animals and by use of liquid chromatography-mass spectrometry in 2 llamas.
Results—Median elimination half-life was 11 hours (range, 9.3 to 29.8 hours) in alpacas and 16 hours (range, 5.4 to 17 hours) in llamas. The volume of distribution at steady state was 0.60 L/kg (range, 0.45 to 0.93 L/kg) in alpacas and 0.75 L/kg (range, 0.68 to 1.15 L/kg) in llamas. Total plasma clearance was 44 mL/h/kg (range, 24 to 56 mL/h/kg) in alpacas and 42 mL/h/kg (range, 30 to 109 mL/h/kg) in llamas.
Conclusions and Clinical Relevance—High-performance liquid chromatography and liquid chromatography-mass spectrometry were suitable methods for determination of plasma caffeine concentrations in alpacas and llamas. Plasma caffeine concentration-time curves were best described by a 2-compartment model. Elimination half-lives, plasma clearance, volume of distribution at steady state, and mean residence time were not significantly different between alpacas and llamas. Intravenous administration of caffeine at a dose of 3 mg/kg did not induce clinical signs of excitement.
Abstract
Case Description—A 13-year-old llama was examined because of lethargy, inappetence, and syncope.
Clinical Findings—Physical examination revealed muffled heart and lung sounds and peripheral edema. Clinicopathologic abnormalities included lymphopenia, hyperglycemia, prerenal azotemia, mild hyponatremia, mild hypoalbuminemia, and high γ-glutamyltransferase and creatine kinase activities. On ultrasonography, the liver appeared hyperechoic and ascites and pleural effusion were seen. Echocardiography revealed severe dilatation of the right atrium, right ventricle, and pulmonary artery; severe tricuspid regurgitation; and high right ventricular systolic pressure consistent with right-sided heart failure secondary to pulmonary hypertension.
Treatment and Outcome—Treatment with furosemide was attempted, but because of failing health, the llama was euthanized 4 weeks later. Macronodular cirrhosis of the liver, glomerulonephritis, and intimal fibrosis and medial hypertrophy of muscular pulmonary arteries were seen on histologic examination of postmortem specimens.
Clinical Relevance—Findings in this case were similar to those reported for human patients with portopulmonary hypertension secondary to hepatic cirrhosis. Pulmonary hypertension secondary to hepatic disease should be considered in the differential diagnosis of right-sided heart failure.
