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Abstract

OBJECTIVE

To identify environmental and other variables associated with a diagnosis of granulomatous meningoencephalomyelitis (GME) in dogs.

DESIGN

Case-control study.

ANIMALS

31 dogs that received a histologic diagnosis of GME (case dogs) from January 2003 to January 2014 and 91 age- and breed-matched dogs.

PROCEDURES

Data were obtained from each dog's medical records regarding home address, signalment, body weight, body condition score (BCS), vaccination history, and date of diagnosis (case dogs) or visit (control dogs). Home address data were used to determine the human population density in each dog's geographic region. Seasonal distributions of GME diagnoses in the case group were evaluated for differences. Case and control dogs were compared with respect to the remaining variables.

RESULTS

For case dogs, no significant difference was identified among seasons in the distribution of GME diagnoses; however, such diagnoses were more common in the spring than in other seasons. No significant differences were identified between case and control dogs in age, body weight, BCS, human population density, season of diagnosis or visit, or time of last vaccination. Although females appeared more likely than males to have a GME diagnosis, this association was not significant and did not change when BCS, time since last vaccination, or human population density was considered.

CONCLUSIONS AND CLINICAL RELEVANCE

None of the evaluated factors, including investigated environmental triggers, were associated with a GME diagnosis in the dogs of this study. Additional research is warranted involving dogs from a broader geographic area.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate the antinociceptive effects and duration of action of nalbuphine HCl administered IM on thermal thresholds in Hispaniolan Amazon parrots (Amazona ventralis).

Animals—14 healthy adult Hispaniolan Amazon parrots of unknown sex.

Procedures—3 doses of nalbuphine (12.5, 25, and 50 mg/kg, IM) and saline (0.9% NaCl) solution (control treatment) were evaluated in a blinded complete crossover experimental design by use of foot withdrawal threshold to a noxious thermal stimulus. Baseline data on thermal threshold were generated 1 hour before administration of nalbuphine or saline solution; thermal threshold measurements were obtained 0.5, 1.5, 3, and 6 hours after administration.

Results—Nalbuphine administered IM at 12.5 mg/kg significantly increased the thermal threshold (mean change, 2.4°C), compared with results for the control treatment, and significantly changed thermal threshold for up to 3 hours, compared with baseline results (mean change, 2.6° to 3.8°C). Higher doses of nalbuphine did not significantly change thermal thresholds, compared with results for the control treatment, but had a significant effect, compared with baseline results, for up to 3 and 1.5 hours after administration, respectively.

Conclusions and Clinical Relevance—Nalbuphine administered IM at 12.5 mg/kg significantly increased the foot withdrawal threshold to a thermal noxious stimulus in Hispaniolan Amazon parrots. Higher doses of nalbuphine did not result in significantly increased thermal thresholds or a longer duration of action and would be expected to result in less analgesic effect than lower doses. Further studies are needed to fully evaluate the analgesic effects of nalbuphine in psittacine species.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the antinociceptive and sedative effects of tramadol in Hispaniolan Amazon parrots (Amazona ventralis) following IV administration.

Animals—11 healthy Hispaniolan Amazon parrots of unknown sex.

Procedures—Tramadol hydrochloride (5 mg/kg, IV) and an equivalent volume (≤ 0.34 mL) of saline (0.9% NaCl) solution were administered to parrots in a complete crossover study design. Foot withdrawal response to a thermal stimulus was determined 30 to 60 minutes before (baseline) and 15, 30, 60, 120, and 240 minutes after treatment administration; agitation-sedation scores were determined for parrots at each of those times.

Results—The estimated mean changes in temperature from the baseline value that elicited a foot withdrawal response were 1.65° and −1.08°C after administration of tramadol and saline solution, respectively. Temperatures at which a foot withdrawal response was elicited were significantly higher than baseline values at all 5 evaluation times after administration of tramadol and were significantly lower than baseline values at 30, 120, and 240 minutes after administration of saline solution. No sedation, agitation, or other adverse effects were observed in any of the parrots after administration of tramadol.

Conclusions and Clinical Relevance—Tramadol hydrochloride (5 mg/kg, IV) significantly increased the thermal nociception threshold for Hispaniolan Amazon parrots in the present study. Sedation and adverse effects were not observed. These results are consistent with results of other studies in which the antinociceptive effects of tramadol after oral administration to parrots were determined.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate the analgesic efficacy of meloxicam in parrots with experimentally induced arthritis, with extent of weight bearing and rotational perch walking used as outcome measures.

Animals—15 adult Hispaniolan parrots (Amazona ventralis).

Procedures—Arthritis was experimentally induced via intra-articular injection of microcrystalline sodium urate suspension (MSU) into 1 intertarsal joint. Parrots were treated in a crossover design. Five treatments were compared as follows: meloxicam (4 dosages) at 0.05, 0.1, 0.5, and 1.0 mg/kg (IM, q 12 h, 3 times) and 0.03 mL of saline (0.9% NaCl) solution (IM, q 12 h, 3 times). The first treatment was given 6 hours following MSU administration. Lameness was assessed by use of a biomechanical perch to record weight-bearing load and a rotational perch to determine dexterity. Feces were collected to assay for occult blood.

Results—Parrots treated with meloxicam at 1.0 mg/kg had significantly better return to normal (baseline) weight bearing on the arthritic pelvic limb, compared with control parrots or parrots treated with meloxicam at 0.05, 0.1, and 0.5 mg/kg. All fecal samples collected from parrots following induction of arthritis and treatment with meloxicam had negative results for occult blood.

Conclusions and Clinical Relevance—Meloxicam administered at 1.0 mg/kg, IM, every 12 hours effectively relieved arthritic pain in parrots.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate antinociceptive effects on thermal thresholds after oral administration of tramadol hydrochloride to Hispaniolan Amazon parrots (Amazona ventralis).

Animals—15 healthy adult Hispaniolan Amazon parrots.

Procedures—2 crossover experiments were conducted. In the first experiment, 15 parrots received 3 treatments (tramadol at 2 doses [10 and 20 mg/kg] and a control suspension) administered orally. In the second experiment, 11 parrots received 2 treatments (tramadol hydrochloride [30 mg/kg] and a control suspension) administered orally. Baseline thermal foot withdrawal threshold was measured 1 hour before drug or control suspension administration; thermal foot withdrawal threshold was measured after administration at 0.5, 1.5, 3, and 6 hours (both experiments) and also at 9 hours (second experiment only).

Results—For the first experiment, there were no overall effects of treatment, hour, period, or any interactions. For the second experiment, there was an overall effect of treatment, with a significant difference between tramadol hydrochloride and control suspension (mean change from baseline, 2.00° and −0.09°C, respectively). There also was a significant change from baseline for tramadol hydrochloride at 0.5, 1.5, and 6 hours after administration but not at 3 or 9 hours after administration.

Conclusions and Clinical Relevance—Tramadol at a dose of 30 mg/kg, PO, induced thermal antinociception in Hispaniolan Amazon parrots. This dose was necessary for induction of significant and sustained analgesic effects, with duration of action up to 6 hours. Further studies with other types of noxious stimulation, dosages, and intervals are needed to fully evaluate the analgesic effects of tramadol hydrochloride in psittacines.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate serial blood gas values and lactate concentrations in 3 fish species undergoing surgery and to compare blood lactate concentrations between fish that survived and those that died during the short-term postoperative period.

Design—Prospective cohort study.

Animals—10 yellow perch, 5 walleye pike, and 8 koi.

Procedures—Blood samples were collected from each fish at 3 time points: before anesthesia, during anesthesia, and immediately after surgery. Blood gas values and blood lactate concentrations were measured. Fish were monitored for 2 weeks postoperatively.

Results—All walleye and koi survived, but 2 perch died. Blood pH significantly decreased in perch from before to during anesthesia, but increased back to preanesthesia baseline values after surgery. Blood Pco 2 decreased significantly in perch from before anesthesia to immediately after surgery, and also from during anesthesia to immediately after surgery, whereas blood Pco 2 decreased significantly in koi from before to during anesthesia. Blood Po 2 increased significantly in both perch and koi from before to during anesthesia, and also in koi from before anesthesia to immediately after surgery. For all 3 species, blood lactate concentrations increased significantly from before anesthesia to immediately after surgery. Blood lactate concentration (mean ± SD) immediately after surgery for the 8 surviving perch was 6.06 ± 1.47 mmol/L, which was significantly lower than blood lactate concentrations in the 2 nonsurviving perch (10.58 and 10.72 mmol/L).

Conclusions and Clinical Relevance—High blood lactate concentrations following surgery in fish may be predictive of a poor short-term postoperative survival rate.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate the microcrystalline sodium urate (MSU) method for inducing arthritis in parrots and to compare the analgesic efficacy of long-acting liposome-encapsulated butorphanol (LEBT), carprofen, or a combination of both.

Animals—20 Hispaniolan parrots.

Procedures—MSU was injected into a tibiotarsal-tarsometatarsal (intertarsal) joint to induce arthritis (time 0). Four treatments were compared (LEBT [15 mg/kg, SC] administered once at time 0; injections of carprofen [3 mg/kg, IM, q 12 h] starting at time 0; administration of LEBT plus carprofen; and a control treatment of saline [0.9% NaCl] solution). Weight load testing and behavioral scoring were conducted at 0, 2, 6, 26, and 30 hours.

Results—Injection of MSU into the intertarsal joint induced arthritis, which resolved within 30 hours. Treatment with LEBT or LEBT plus carprofen resulted in significantly greater weight-bearing load on the limb with induced arthritis, compared with the control treatment. Treatment with carprofen alone caused a slight but nonsignificant improvement in weight-bearing load on the arthritic limb, compared with the control treatment. Behaviors associated with motor activity and weight bearing differed between the control and analgesic treatments.

Conclusions and Clinical Relevance—Butorphanol was an effective treatment for pain associated with arthritis, but carprofen administered every 12 hours was insufficient. Injection of MSU to induce arthritis in a single joint was a good method for evaluating tonic pain in parrots, and measurement of the weight-bearing load was accurate for assessment of arthritic pain; however, behavioral changes associated with pain were subtle.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate injection of microcrystalline sodium urate (MSU) for inducing articular pain in green-cheeked conures (Pyrrhura molinae) and the analgesic efficacy of liposome-encapsulated butorphanol tartrate (LEBT) by use of weight load data, behavioral scores, and fecal corticosterone concentration.

Animals—8 conures.

Procedures—In a crossover study, conures were randomly assigned to receive LEBT (15 mg/kg) or liposomal vehicle subsequent to experimental induction of arthritis or sham injection. The MSU was injected into 1 tibiotarsal-tarsometatarsal (intertarsal) joint to induce arthritis (time 0). Weight-bearing load and behavioral scores were determined at 0, 2, 6, 26, and 30 hours.

Results—MSU injection into 1 intertarsal joint caused a temporary decrease in weight bearing on the affected limb. Treatment of arthritic conures with LEBT resulted in significantly more weight bearing on the arthritic limb than treatment with vehicle. Administration of vehicle to arthritic conures caused a decrease in activity and feeding behaviors during the induction phase of arthritis, but as the arthritis resolved, there was a significant increase in voluntary activity at 30 hours and feeding behaviors at 26 and 30 hours, compared with results for LEBT treatment of arthritic birds. Treatment with LEBT or vehicle in conures without arthritis resulted in similar measurements for weight bearing and voluntary and motivated behaviors.

Conclusions and Clinical Relevance—Experimental induction of arthritis in conures was a good method for evaluating tonic pain. Weight-bearing load was the most sensitive measure of pain associated with induced arthritis. Pain associated with MSU-induced arthritis was alleviated by administration of LEBT.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate the thermal antinociceptive effects and duration of action of nalbuphine decanoate after IM administration to Hispaniolan Amazon parrots (Amazona ventralis).

Animals—10 healthy adult Hispaniolan Amazon parrots of unknown sex.

Procedures—Nalbuphine decanoate (33.7 mg/kg) or saline (0.9% NaCl) solution was administered IM in a randomized complete crossover experimental design (periods 1 and 2). Foot withdrawal threshold to a noxious thermal stimulus was used to evaluate responses. Baseline thermal withdrawal threshold was recorded 1 hour before drug or saline solution administration, and thermal foot withdrawal threshold measurements were repeated 1, 2, 3, 6, 12, 24, 48, and 72 hours after drug administration.

Results—Nalbuphine decanoate administered IM at a dose of 33.7 mg/kg significantly increased thermal foot withdrawal threshold, compared with results after administration of saline solution during period 2, and also caused a significant change in withdrawal threshold for up to 12 hours, compared with baseline values.

Conclusions and Clinical Relevance—Nalbuphine decanoate increased the foot withdrawal threshold to a noxious thermal stimulus in Hispaniolan Amazon parrots for up to 12 hours and provided a longer duration of action than has been reported for other nalbuphine formulations. Further studies with other types of nociceptive stimulation, dosages, and dosing intervals as well as clinical trials are needed to fully evaluate the analgesic effects of nalbuphine decanoate in psittacine birds.

Full access
in American Journal of Veterinary Research