Christal G. Pollock

Single and Multiple-Dose Pharmacokinetics of Meloxicam After Oral Administration to the Rabbit (Oryctolagus cuniculus)

Abstract The nonsteroidal anti-inflammatory drug (NSAID) meloxicam is a very popular anti-inflammatory, analgesic, and antipyretic agent used in veterinary medicine. To determine the pharmacokinetics of this NSAID in rabbits following a single dose and 10-day period of dosing, eight clinically normal, 8-mo-old New Zealand white rabbits (Oryctolagus cuniculus) were administered 0.2 mg/kg meloxicam p.o. daily. Pharmacokinetic analysis of the meloxicam was determined via noncompartmental analysis. After oral administration, mean ± standard deviation values for area under the curve were 1.8 ± 0.50 and 2.1 ± 0.55 µg × h/ml, and maximum plasma concentrations were 0.17 ± 0.06 and 0.24 ± 0.07 µg/ml for Day 1 and Day 10, respectively. The half-life was approximately 8 hr. Administration of meloxicam at a dosage of 0.2 to 0.3 mg/kg p.o. every 24 hr is suggested. Although a higher dose may be required for optimum effects, this would require efficacy and safety studies in this species. Meloxicam administered at 0.2 mg/kg p.o. daily for 10 day was well tolerated by the rabbits.

FUNGAL DERMATITIS IN CAPTIVE PINNIPEDS

Abstract Fungal dermatitis was diagnosed in two captive gray seals (Halichoerus grypus) and four harbor seals (Phoca vitulina) between 1992 and 1994. Trichophyton mentagrophytes, Malassezia spp., and Yarrowia (Candida) lipolytica were isolated. Erythematous, thickened, alopecic skin lesions were present on the face and on the flippers, particularly around the nail bed. The two most important environmental factors associated with development of fungal dermatitis appeared to be excessive chlorination of pool water and warm water temperature.

Sedative Effects of Medetomidine in Pigeons (Columba livia)

Abstract The sedative effects of medetomidine administered alone or in combination with ketamine or midazolam were evaluated in 20 adult pigeons (Columba livia). Six to 12 pigeons were randomly assigned to each of 5 treatment groups. Medetomidine administered alone (80, 150, or 200 μg/kg IM) caused effects ranging from ataxia to sternal recumbency, but the righting reflex was always retained. The level of sedation resulting from medetomidine (80 μg/kg IM) in combination with either ketamine (5 mg/kg IM) or midazolam (0.5 mg/kg IM) was variable; birds exhibited signs ranging from mild to heavy sedation. Heavy sedation was defined as loss of the righting reflex and profound muscle relaxation. Medetomidine-ketamine resulted in heavy sedation in 3 of 9 birds, whereas 5 of 12 birds were heavily sedated with medetomidine-midazolam. Atipamizole (0.5 mg/kg IM) was administered to reverse the effects of medetomidine. The length of time (mean ± SD) from atipamizole injection until loss of ataxia and return of full responsiveness ranged from 10 ± 4.0 to 17 ± 5.0 minutes with medetomidine alone. Birds sedated with medetomidine-ketamine recovered within 20 ± 12.0 minutes, and those sedated with medetomidine-midazolam recovered within 38 ± 11.0 minutes. Atipamizole was given 30 minutes after administration of medetomidine alone and medetomidine-ketamine, whereas birds given medetomidine-midazolam received atipamizole 50 minutes after administration. Medetomidine used alone or in combination with ketamine or midazolam cannot be recommended for sedation of pigeons at the dosages described in this study. Used alone, medetomidine was inadequate for restraint, and when administered with ketamine or midazolam, sedative effects were unpredictable.

TYZZER'S DISEASE IN A RED PANDA {AILURUS FULGENS FULGENS)

Abstract A debilitated 9-yr-old female red panda (Ailurus fulgens fulgens) with a recent history of corticosteroid administration displayed anorexia, depression, and diarrhea for 2 days. Blood work revealed a moderate nonregenerative anemia, leukocytosis, hypokalemia, hyperbilirubinemia, and mildly elevated alanine aminotransferase and aspartate aminotransferase. Serology was negative for occult heartworm, Toxoplasma gondii, feline leukemia virus, feline infectious peritonitis, feline immunodeficiency virus, and canine distemper virus. Electron microscopy of the feces demonstrated corona-like virus particles. The panda died 3 days after initial presentation. Histologic findings included multifocal, acute, hepatic necrosis and diffuse, necrotizing colitis. Liver and colon lesions contained intracellular, curved, spore-forming, gram-negative, silver-positive rods morphologically consistent with Clostridium piliforme. This panda most likely contracted Tyzzers disease subsequent to having a compromised immune system after corticosteroid administration and concurrent disease.

West Nile Virus in the Americas

ABSTRACT West Nile virus causes sporadic disease in the Eastern hemisphere that is often asymptomatic or mild, whereas in the Western hemisphere, West Nile virus has been associated with illness and profound mortality in many avian species. West Nile virus might have been transported to North America by an infected mosquito or the virus could have entered within a vertebrate host like a bird. Although the most important method of West Nile virus transmission is by Culex species mosquitoes, additional modes of transmission have been identified. West Nile virus has been isolated from almost 300 species of Western birds. The long-term effects on common species such as corvids, sparrows, grackles, finches, hawks, and robins are still being debated. However the potential effect of West Nile virus on small populations or species with limited geographic distribution, such as Hawaiian avifauna, could be much more catastrophic.

Single- and multiple-dose pharmacokinetics of marbofloxacin after oral administration to rabbits.

OBJECTIVE-To determine the pharmacokinetics of marbofloxacin after oral administration every 24 hours to rabbits during a 10-day period. ANIMALS-8 healthy 9-month-old female New Zealand White rabbits. PROCEDURES-Marbofloxacin (5 mg/kg) was administered orally every 24 hours to 8 rabbits for 10 days. The first day of administration was designated as day 1. Blood samples were obtained at 0, 0.17, 0.33, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6, 8, 12, and 24 hours on days 1 and 10 of marbofloxacin administration. Plasma marbofloxacin concentrations were quantitated by use of a validated liquid chromatography-mass spectrometry assay. Pharmacokinetic analysis of marbofloxacin was analyzed via noncompartmental methods. RESULTS-After oral administration, mean +/- SD area under the curve was 10.50 +/- 2.00 microg.h/mL and 10.90 +/- 2.45 microg.h/mL, maximum plasma concentration was 1.73 +/- 0.35 microg/mL and 2.56 +/- 0.71 microg/mL, and harmonic mean terminal half-life was 8.0 hours and 3.9 hours for days 0 and 10, respectively. CONCLUSIONS AND CLINICAL RELEVANCE-Marbofloxacin administered orally every 24 hours for 10 days appeared to be absorbed well and tolerated by rabbits. Administration of marbofloxacin at a dosage of 5 mg/kg, PO, every 24 hours is recommended for rabbits to control infections attributable to susceptible bacteria.

Encephalitis Caused by Sarcocystis falcatula-like Organisms in a White Cockatoo (Cacatua alba)

Abstract A 23-year-old white cockatoo (Cacatua alba) was examined because of severe muscle wasting and acute onset of ataxia and right head tilt. Results of diagnostic tests were inconclusive, and the bird died despite supportive care and empirical treatment. Results of necropsy and histopathologic examination revealed cysts within skeletal and cardiac muscle, meronts (schizonts) within cerebellar tissue, and encephalitis caused by infection with Sarcocystis falcatula-like organisms.

Cardiopulmonary and anesthetic effects of medetomidine-ketamine-butorphanol and antagonism with atipamezole in servals (Felis serval).

Abstract Seven (three male and four female) 4–7-yr old captive servals (Felis serval) weighing 13.7 ± 2.3 kg were used to evaluate the cardiopulmonary and anesthetic effects of combined intramuscular injections of medetomidine (47.4 ± 10.3 µg/kg), ketamine (1.0 ± 0.2 mg/kg), and butorphanol (0.2 ± 0.03 mg/kg). Inductions were smooth and rapid (11.7 ± 4.3 min) and resulted in good muscle relaxation. Significant decreases in heart rate (85 ± 12 beats/min) at 10 min after injection and respiratory rate (27 ± 10 breaths/min) at 5 min after injection continued throughout the immobilization period. Rectal temperature and arterial blood pressure did not change significantly. The Pao2 decreased significantly, and Paco2 increased significantly during immobilization but remained within clinically acceptable limits. Hypoxemia (Pao2 < 60 mm Hg) was not noted, and arterial blood oxygen saturation (Sao2) was greater than 90% at all times. Relative arterial oxygen saturation (Spo2) values, indicated by pulse oximetry, were lower than Sao2 values. All animals could be safely handled while sedated. Administration of atipamezole (236.8 ± 51.2 µg/kg half i.v. and half s.c.), an α2 antagonist, resulted in rapid (4.1 ± 3 min to standing) and smooth recoveries.

SERIAL IMMOBILIZATION OF A BRAZILIAN TAPIR (TAPIRUS TERRESTRUS) WITH ORAL DETOMIDINE AND ORAL CARFENTANIL

Abstract Detomidine (0.17 ± 0.03 mg/kg, p.o.) followed in 20 min by carfentanil (7.88 ± 1.85 μg/kg, p.o.) reliably restrained an adult Brazilian tapir (Tapirus terrestrus) eight times for short medical procedures. Detomidine caused head droop, sawhorse stance, ataxia or head pressing (or both). Sternal or lateral recumbency was reached within 10.75 ± 7.6 min of carfentanil administration. Recoveries after i.v. and s.c. administration of yohimbine and naltrexone were smooth and rapid, with the tapir standing within 2–5 min.

Companion birds in early America

Historically, bird keeping in Europe was principally for royalty and clergymen. During the Age of Exploration in the 15th and 16th centuries, Europeans were introduced to the plentiful bird life of the New World. In fact, parrots were the first animals exported to the Old World. When Europeans began to explore the Canary Islands, they also returned to Europe with a small exotic passerine bird: the canary (Serinus canaria). Canaries and New World parrots were initially sold to European aristocracy, but, over time, merchants and other wealthy individuals began to acquire these birds. When Europeans immigrated to North America in the 17th century, they brought with them the practice of bird keeping. By the 19th and early 20th centuries, birds were the most popular indoor pets in the United States. The popularity of pet birds crossed class lines as well as racial and ethnic barriers. Solitary caged birds were common in working-class households, whereas wealthy families often kept a variety of birds in aviaries. Like the televisions and radios of present day, birds brought beautiful song and a cheerful level of noise that was welcome in quiet, early American homes. Songbirds were also considered exemplary examples of monogamy and devoted parenting, which made them ideal role models for middleclass family life.