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Abstract

Objective—To determine whether corn snakes exposed to UVB radiation have increased plasma 25-hydroxyvitamin D3 concentrations, compared with control snakes.

Animals—12 corn snakes (Elaphe guttata).

Procedures—After an acclimation period in individual enclosures, a blood sample was collected from each snake for assessment of plasma 25-hydroxyvitamin D3 concentration. Six snakes were provided with no supplemental lighting, and 6 snakes were exposed to light from 2 full-spectrum coil bulbs. By use of a radiometer-photometer, the UVA and UVB radiation generated by the bulbs were measured in each light-treated enclosure at 3 positions at the basking surface and at 2.54 cm (1 inch) below each bulb surface; the arithmetic mean values for the 3 positions at the basking surface and each individual bulb surface were calculated immediately after the start of the study and at weekly intervals thereafter. At the end of the study (day 28), another blood sample was collected from each snake to determine plasma 25-hydroxyvitamin D3 concentration.

Results—Mean ± SD plasma concentration of 25-hydroxyvitamin D3 in snakes that were provided with supplemental lighting (196 ± 16.73 nmol/L) differed significantly from the value in control snakes (57.17 ± 15.28 nmol/L). Mean exposure to UVA or UVB did not alter during the 4-week study period, although the amount of UVA recorded near the bulb surfaces did change significantly.

Clinical Relevance—These findings have provided important insight into the appropriate UV radiation requirements for corn snakes. Further investigation will be needed before exact husbandry requirements can be determined.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate agreement of blood glucose concentrations measured in juvenile white-tailed deer (Odocoileus virginianus) by use of 2 point-of-care (POC) blood glucose meters and 1 portable chemistry analyzer with values obtained in serum by use of a standard laboratory chemistry analyzer, and to evaluate agreement between results obtained with the 2 POC meters.

Design—Prospective evaluation study.

Sample—14 venous blood samples from 14 healthy white-tailed deer fawns.

Procedures—Blood glucose concentration was measured with each of 2 POC meters. The remainder of the sample was divided into 2 tubes (1 that contained lithium heparin and 1 with no anticoagulant). Glucose concentration in anticoagulated whole blood was measured with the portable analyzer. Serum was collected from the remaining sample for measurement of glucose concentrations with the laboratory analyzer. Bland-Altman plots were used to assess agreement.

Results—Agreement between POC blood glucose meters and the laboratory analyzer was poor; mean values for bias were 2.9 mg/dL (95% limits of agreement [LOA], −70.2 to 76.0 mg/dL) and −30.8 mg/dL (95% LOA, −111.6 to 49.9 mg/dL), respectively. Agreement between the 2 POC meters was also poor (bias, 31.0 mg/dL; 95% LOA, −47.2 to 109.2 mg/dL). Agreement between the portable analyzer and the laboratory analyzer was good (bias, −1.6 mg/dL; 95% LOA, −15.3 to 12.1 mg/dL).

Conclusions and Clinical Relevance—Results suggested that the POC blood glucose meters used in this study are not appropriate for measurement of blood glucose concentrations in juvenile white-tailed deer.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the correlation between plasma iron concentrations and gastric pH in a population of captive Atlantic bottlenose dolphins (Tursiops truncatus).

Animals—6 adult female dolphins that ranged from 16 to 30 years of age.

Procedures—Blood and gastric samples were collected from each dolphin to allow measurement of plasma iron concentrations and gastric pH, respectively. Samples were collected each month for 12 months.

Results—Within each dolphin, plasma iron concentrations and gastric pH did not differ significantly over time. There was a strong negative correlation (r = −0.85) between plasma iron concentration and gastric pH, which suggested that dolphins with a lower gastric pH had a higher plasma iron concentration.

Conclusions and Clinical Relevance—Analysis of results reported here suggested that gastric pH may play an important role in iron absorption in dolphins.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the safety, efficacy, and effects on hemolymph gas analysis variables of sevoflurane anesthesia in Chilean rose tarantulas (Grammostola rosea).

Animals—12 subadult Chilean rose tarantulas of unknown sex.

Procedures—Spiders were anesthetized in a custom chamber with sevoflurane (5% in oxygen [1.0 L/min]), then allowed to recover in 100% oxygen. Righting reflex was evaluated every 3 minutes during anesthesia to determine time to anesthetic induction and recovery. Hemolymph samples were collected from an intracardiac location prior to and after induction of anesthesia and evaluated to determine various gas analysis variables.

Results—Mean ± SD induction and recovery times were 16 ± 5.91 minutes and 29 ± 21.34 minutes, respectively. Significant differences were detected for Po 2, base excess, and glucose and ionized magnesium concentrations between hemolymph samples obtained before anesthesia and those obtained after induction of anesthesia.

Conclusions and Clinical Relevance—Results of this study suggested that the use of sevoflurane as an anesthetic agent for Chilean rose tarantulas was safe and effective. Various hemolymph sample gas analysis values changed during anesthesia.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the effects of recumbency on air sac volume, lung volume, and lung densities in CT images of healthy, conscious and anesthetized spontaneously breathing Humboldt penguins (Spheniscus humboldti).

Animals—25 adult (13 male and 12 female) Humboldt penguins.

Procedures—CT images of conscious penguins in ventral recumbency and anesthetized penguins in dorsal, ventral, and right lateral recumbency were obtained. Air sac volume, lung volume, and lung densities in CT images were calculated. A paired samples t test was used to determine whether right and left lung densities differed among recumbencies. Repeated-measures ANOVA (controlled for sex and order of recumbencies during CT) was used to determine whether air sac or lung volumes differed among recumbencies.

Results—Recumbency had a significant effect on air sac volume but not lung volume. Air sac volume was largest in conscious penguins in ventral recumbency (mean ± SD, 347.2 ± 103.1 cm3) and lowest in anesthetized penguins in dorsal recumbency (median, 202.0 cm3; 10th to 90th percentile, 129.2 to 280.3 cm3). Lung densities were highest in anesthetized penguins in dorsal recumbency (right lung median, 0.522 g/cm3; left lung median, 0.511 g/cm3) and lowest in anesthetized penguins in ventral recumbency (right lung median, 0.488 g/cm3; left lung median, 0.482 g/cm3).

Conclusions and Clinical Relevance—Results indicated that anesthetized Humboldt penguins had the lowest air sac volume and highest lung densities in dorsal recumbency. Therefore, this recumbency may not be recommended. Minimal changes in lung volume were detected among recumbencies or between conscious and anesthetized penguins.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To evaluate effects of alfaxalone on heart rate (HR), opercular rate (OpR), results of blood gas analysis, and responses to noxious stimuli in oscar fish (Astronotus ocellatus).

ANIMALS 6 healthy subadult oscar fish.

PROCEDURES Each fish was immersed in water containing 5 mg of alfaxalone/L. Water temperature was maintained at 25.1°C, and water quality was appropriate for this species. The HR, OpR, response to noxious stimuli, and positioning in the tank were evaluated, and blood samples for blood gas analysis were collected before (baseline), during, and after anesthesia.

RESULTS Immersion anesthesia of oscar fish with alfaxalone (5 mg/L) was sufficient for collection of diagnostic samples in all fish. Mean ± SD induction time was 11 ± 3.8 minutes (minimum, 5 minutes; maximum, 15 minutes), and mean recovery time was 37.5 ± 13.7 minutes (minimum, 20 minutes; maximum, 55 minutes). There was a significant difference in OpR over time, with respiratory rates significantly decreasing between baseline and anesthesia and then significantly increasing between anesthesia and recovery. There was no significant difference in HR over time. Median lactate concentrations were significantly increased in all anesthetized fish. Other physiologic or blood gas variables did not change significantly.

CONCLUSIONS AND CLINICAL RELEVANCE Alfaxalone should be considered as a readily available and easy-to-use anesthetic for oscar fish. Because it is more likely to be found in veterinary hospitals than other traditional anesthetics for fish, its value as an anesthetic for other species of fish should also be considered.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To determine tear film concentrations of doxycycline in ophthalmologically normal dogs following oral doxycycline administration.

DESIGN Crossover study.

ANIMALS 10 privately owned dolichocephalic or mesaticephalic dogs free of ophthalmic disease.

PROCEDURES Dogs were randomly assigned to receive doxycycline hyclate first at 5 mg/kg (2.3 mg/lb) or 10 mg/kg (4.5 mg/lb), PO, every 12 hours for 5 days, beginning on day 1. Doxycycline was administered 1 hour prior to feeding. Tear samples were collected from days 1 through 10 approximately 3 hours after the morning dose was administered. Following a 3-week washout period, dogs received the alternative dose in the same conditions. Doxycycline concentration in tear samples from 1 eye (same eye used for both sessions) was measured via liquid chromatography–mass spectrometry and compared between the 2 doxycycline doses.

RESULTS Doxycycline was detected in tear samples of all dogs from days 1 through 10 for both doxycycline doses. Median peak doxycycline concentrations for the 5 mg/kg and 10 mg/kg doses were 2.19 ng/mL on day 3 and 4.32 ng/mL on day 4, respectively. Concentrations differed significantly with time, but this difference was not influenced by dose, dose order, or eye. A significant positive correlation was identified between doxycycline concentration and body weight (r = 0.22).

CONCLUSIONS AND CLINICAL RELEVANCE Detectable doxycycline concentrations were achieved in the tear film of ophthalmologically normal dogs following oral administration of doxycycline at 5 or 10 mg/kg, every 12 hours. Dose had no significant effect on tear film concentration of the drug.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To determine mortality rates for dogs with severe anaphylaxis and identify potential prognostic factors.

ANIMALS

67 dogs with suspected anaphylaxis graded as severe.

PROCEDURES

Dogs were classified on the basis of outcome as survivors and nonsurvivors. Medical records were reviewed, and data were extracted including signalment, examination findings, time to hospital admission from onset of clinical signs, CBC results, serum biochemical analysis results, coagulation testing results, and findings on abdominal ultrasonography. Initial treatment within the first 6 hours after hospital admission was recorded for analysis, specifically including the use of epinephrine, diphenhydramine, corticosteroids, antimicrobials, fresh-frozen plasma, and supplemental dextrose.

RESULTS

The overall mortality rate was 14.9% (10/67) for dogs with anaphylaxis graded as severe. Serum phosphorus concentration and prothrombin time (PT) were significantly higher in nonsurvivors, compared with survivors. Nonsurvivors had lower presenting body temperatures than survivors. Serum phosphorus concentration ≥ 12.0 mmol/L, hypoglycemia within 6 hours after hospital admission, high PT value, concurrently high PT and partial thromboplastin time (PTT) values > 50% above the reference range limit, and the need for supplemental dextrose were associated with death. The incidences of coagulopathy and peritoneal effusion were unexpectedly high (85.2% and 65.5% of dogs, respectively) but were not indicative of survival.

CONCLUSIONS AND CLINICAL RELEVANCE

Despite the poor presenting clinical condition seen in dogs with severe anaphylaxis, the rate of survival with treatment was fairly high. Coagulopathy and the presence of peritoneal effusion were common findings in dogs with severe anaphylaxis. Serum phosphorus concentration ≥ 12.0 mmol/L, high PT value, concurrent increases of PT and PTT values > 50% above reference range limits, hypoglycemia within 6 hours after hospital admission, and the need for supplemental dextrose were associated with death.

Restricted access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine plasma osmolality in healthy adult Hispaniolan Amazon parrots (Amazona ventralis) and validate osmolality equations in these parrots.

Animals—20 healthy adult Hispaniolan Amazon parrots.

Procedures—A blood sample (0.5 mL) was collected from the right jugular vein of each parrot and placed into a lithium heparin microtainer tube. Samples were centrifuged, and plasma was harvested and frozen at −30°C. Samples were thawed, and plasma osmolality was measured in duplicate with a freezing-point depression osmometer. The mean value was calculated for the 2 osmolality measurements.

Results—Plasma osmolality values were normally distributed, with a mean ± SD of 326.0 ± 6.878 mOsm/kg. The equations (2 × [Na+ + K+]) + (glucose/18), which resulted in bias of 2.3333 mOsm/kg and limits of agreement of −7.0940 to 11.7606 mOsm/kg, and (2 × [Na+ + K+]) + (uric acid concentration/16.8) + (glucose concentration/18), which resulted in bias of 5.8117 mOsm/kg and limits of agreement of −14.6640 to 3.0406 mOsm/kg, yielded calculated values that were in good agreement with the measured osmolality.

Conclusions and Clinical Relevance—IV administration of large amounts of hypotonic fluids can have catastrophic consequences. Osmolality of the plasma from parrots in this study was significantly higher than that of commercially available prepackaged fluids. Therefore, such fluids should be used with caution in Hispaniolan Amazon parrots as well as other psittacines. Additional studies are needed to determine whether the estimation of osmolality has the same clinical value in psittacines as it does in other animals.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the degree of agreement between 3 commercially available point-of-care blood glucose meters and a laboratory analyzer for measurement of blood glucose concentrations in Hispaniolan Amazon parrots (Amazona ventralis).

Animals—20 healthy adult Hispaniolan Amazon parrots.

Procedures—A 26-gauge needle and 3-mL syringe were used to obtain a blood sample (approx 0.5 mL) from a jugular vein of each parrot. Small volumes of blood (0.6 to 1.5 μL) were used to operate each of the blood glucose meters, and the remainder was placed into lithium heparin microtubes and centrifuged. Plasma was harvested and frozen at −30°C. Within 5 days after collection, plasma samples were thawed and plasma glucose concen-trations were measured by means of the laboratory analyzer. Agreement between pairs of blood glucose meters and between each blood glucose meter and the laboratory analyzer was evaluated by means of the Bland-Altman method, and limits of agreement (LOA) were calculated.

Results—None of the results of the 3 blood glucose meters agreed with results of the laboratory analyzer. Each point-of-care blood glucose meter underestimated the blood glucose concentration, and the degree of negative bias was not consistent (meter A bias, −94.9 mg/dL [LOA, −148.0 to −41.7 mg/dL]; meter B bias, −52 mg/dL [LOA, −107.5 to 3.5 mg/dL]; and meter C bias, −78.9 mg/dL [LOA, −137.2 to −20.6 mg/dL]).

Conclusions and Clinical Relevance—On the basis of these results, use of handheld blood glucose meters in the diagnosis or treatment of Hispaniolan Amazon parrots and other psittacines cannot be recommended.

Full access
in American Journal of Veterinary Research