Pharmacokinetics and safety of zonisamide after oral administration of single and multiple doses to Hispaniolan Amazon parrots (Amazona ventralis).

OBJECTIVE To determine pharmacokinetics after oral administration of single and multiple doses and to assess the safety of zonisamide in Hispaniolan Amazon parrots (Amazona ventralis). ANIMALS 12 adult Hispaniolan Amazon parrots. PROCEDURES Zonisamide (30 mg/kg, PO) was administered once to 6 parrots in a single-dose trial. Six months later, a multiple-dose trial was performed in which 8 parrots received zonisamide (20 mg/kg, PO, q 12 h for 10 days) and 4 parrots served as control birds. Safety was assessed through monitoring of body weight, attitude, and urofeces and comparison of those variables and results of CBC and biochemical analyses between control and treatment groups. RESULTS Mean ± SD maximum plasma concentration of zonisamide for the single- and multiple-dose trials was 21.19 ± 3.42 µg/mL at 4.75 hours and 25.11 ± 1.81 µg/mL at 2.25 hours after administration, respectively. Mean plasma elimination half-life for the single- and multiple-dose trials was 13.34 ± 2.10 hours and 9.76 ± 0.93 hours, respectively. Pharmacokinetic values supported accumulation in the multiple-dose trial. There were no significant differences in body weight, appearance of urofeces, or appetite between treated and control birds. Although treated birds had several significant differences in hematologic and biochemical variables, all variables remained within reference values for this species. CONCLUSIONS AND CLINICAL RELEVANCE Twice-daily oral administration of zonisamide to Hispaniolan Amazon parrots resulted in plasma concentrations known to be therapeutic in dogs without evidence of adverse effects on body weight, attitude, and urofeces or clinically relevant changes to hematologic and biochemical variables.

Identification of a novel nidovirus in an outbreak of fatal respiratory disease in ball pythons (Python regius).

BACKGROUND: Respiratory infections are important causes of morbidity and mortality in reptiles; however, the causative agents are only infrequently identified. FINDINGS: Pneumonia, tracheitis and esophagitis were reported in a collection of ball pythons (Python regius). Eight of 12 snakes had evidence of bacterial pneumonia. High-throughput sequencing of total extracted nucleic acids from lung, esophagus and spleen revealed a novel nidovirus. PCR indicated the presence of viral RNA in lung, trachea, esophagus, liver, and spleen. In situ hybridization confirmed the presence of intracellular, intracytoplasmic viral nucleic acids in the lungs of infected snakes. Phylogenetic analysis based on a 1,136 amino acid segment of the polyprotein suggests that this virus may represent a new species in the subfamily Torovirinae. CONCLUSIONS: This report of a novel nidovirus in ball pythons may provide insight into the pathogenesis of respiratory disease in this species and enhances our knowledge of the diversity of nidoviruses.

Suspected primary hypoparathyroidism in a domestic ferret (Mustela putorius furo).

CASE DESCRIPTION: A 4-year-old castrated male domestic ferret (Mustela putorius furo) was examined because of a 3-week history of intermittent seizures, signs of depression, hypocalcemia, and hyperphosphatemia. CLINICAL FINDINGS: Plasma biochemical analysis confirmed hyperphosphatemia (17.7 mg/dL) and low concentrations of total (4.3 mg/dL) and ionized (0.49 mmol/L) calcium. Serum parathyroid hormone concentration (2.30 pmol/L) was low or in the low part of the reference interval. TREATMENT AND OUTCOME: Calcium gluconate was administered (2.0 mg/kg/h [0.9 mg/lb/h], IV), followed by a transition to administration of calcium carbonate (53 mg/kg [24.1 mg/lb], PO, q 12 h) and dihydrotachysterol (0.02 mg/kg/d [0.009 mg/lb/d], PO). Attitude of the ferret improved and seizures ceased as blood calcium concentrations increased. The ferret was reexamined because of seizures approximately 1 year after oral maintenance administration of dihydrotachysterol and calcium was initiated. The ferret responded well to emergency and long-term treatment but then was lost to follow-up monitoring. The ferret died approximately 2 years after the initial evaluation and treatment. Hypertrophic cardiomyopathy was diagnosed during necropsy, but the parathyroid glands could not be identified. CLINICAL RELEVANCE: To the authors' knowledge, primary hypoparathyroidism has not previously been reported in a ferret. The condition should be considered for ferrets with hypocalcemia and hyperphosphatemia without azotemia. Treatment with dihydrotachysterol and oral supplementation of calcium appeared to be a viable option for long-term management.