Long-term anticonvulsive treatments have been poorly described in birds, and few pharmacokinetic studies have been performed, with mixed results. Levetiracetam, a new anticonvulsive drug, has shown good efficacy for monotherapy or adjunctive treatment of seizures in both human and veterinary medicine. To determine pharmacokinetics of levetiracetam in Hispaniolan Amazon parrots (Amazona ventralis), 20 healthy birds were randomly divided into 2 groups and administered either a 50 mg/kg (n = 10) or a 100 mg/kg (n = 10) oral dose of levetiracetam with no observable adverse effects. Blood samples were collected at baseline and at 12 time intervals (6 per group) for 16 hours. The concentration–time profiles resembled characteristic absorption, with maximum plasma concentrations of 61.0 μg/mL and 95.1 μg/mL at 60 minutes; terminal half-lives at 2.38 and 2.37 hours; volumes of distribution of 0.807 and 0.773 L/kg, with an area under the curve at 14 100 and 28 820 mg × min/L; and clearance rates of 3.65 and 3.60 mL/min per kg, respectively. Plasma concentrations were greater than 5.5 mg/L for up to 9.4 and 12 hours, suggesting an 8- and 12-hour oral dosing at 50 and 100 mg/kg, respectively, would be sufficient to maintain targeted values. Clinically, doses and frequencies may need escalation based on differences in species and individuals, and drug levels should be monitored.

Voriconazole is effective for treatment of aspergillosis, a common disease in captive red-tailed hawks (Buteo jamaicensis). To determine the disposition and safety of voriconazole after single and multiple, oral doses, 12 adult red-tailed hawks were studied in 2 phases. In phase 1, each bird received a single dose of voriconazole solution (10 mg/kg) by gavage. Blood samples were collected at 0, 0.5, 1, 3, 6, 9, 12, 16, 24, and 36 hours after treatment. In phase 2, each of 8 birds received voriconazole oral solution at 10 mg/kg PO q12h for 14 days. Plasma samples were collected on days 0, 5, and 10 and after the final dose and were processed as in phase 1. Plasma samples were submitted for analysis of voriconazole levels by high-performance liquid chromatography and ultraviolet spectrophotometry and for measurement of selected plasma biochemical parameters. After single dosing, voriconazole concentrations reached a (mean ± SD) peak (C_max) of 4.7 ± 1.3 μg/mL at 2.0 ± 1.2 hours. The disappearance half-life (t_1/2) was 2.8 ± 0.7 hours, and the mean residence time (MRT) was 4.6 ± 0.9 hours. After the last dose at 14 days, the mean C_max of voriconazole was 4.5 ± 2.7 μg/mL at 2.4 ± 1.1 hours. The t_1/2 was 2.1 ± 0.8 hours, and the MRT was 3.5 ± 1.1 hours. Although concentrations of several plasma biochemical parameters were significantly different at study end compared with prestudy concentrations, only plasma creatine kinase activity was outside the reference range. No adverse reactions were observed in any of the birds. After both single and multiple dosing at 10 mg/kg, voriconazole concentrations exceeded the minimum inhibitory concentration to inhibit 90% (MIC₉₀) of Aspergillus species (1 μg/mL) by at least fourfold and remained above the MIC₉₀ for 8.8 ± 1.1 hours after single dosing versus 6.5 ± 1.5 hours after multiple dosing (P = .003). This difference suggests that more frequent dosing (eg, up to q8h) may be necessary to maintain target concentrations during prolonged therapy.

The lipoprotein panel is a useful diagnostic tool that allows clinicians to evaluate blood lipoprotein fractions. It is a standard diagnostic test in human medicine but is poorly understood in avian medicine. Amazon parrots (Amazona species) are popular pets that frequently lead a sedentary lifestyle and are customarily fed high-fat diets. Similar to people with comparable diets and lifestyles, Amazon parrots are prone to obesity and atherosclerosis. In human medicine, these conditions are typically correlated with abnormalities in the lipoprotein panel. To establish reference intervals for the lipoprotein panel in Amazon parrots, plasma samples from 31 captive Amazon parrots were analyzed for concentrations of cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL). The data were also grouped according to sex, diet, body condition score, and age. Aside from HDL levels, which were significantly different between male and female parrots, no intergroup differences were found for any of the lipoprotein fractions.

The American oystercatcher (Haematopus palliatus palliatus) is currently listed as a species of high concern by the United States Shorebird Conservation Plan. Because nutritional status directly impacts overall health and reproduction of individuals and populations, adequate management of a wildlife population requires intimate knowledge of a species' diet and nutrient requirements. Fat-soluble vitamin concentrations in blood plasma obtained from American oystercatchers and proximate, vitamin, and mineral composition of various oystercatcher prey species were determined as baseline data to assess nutritional status and nutrient supply. Bird and prey species samples were collected from the Cape Romain region, South Carolina, USA, and the Altamaha River delta islands, Georgia, USA, where breeding populations appear relatively stable in recent years. Vitamin A levels in blood samples were higher than ranges reported as normal for domestic avian species, and vitamin D concentrations were lower than anticipated based on values observed in poultry. Vitamin E levels were within ranges previously reported for avian groups with broadly similar feeding niches such as herons, gulls, and terns (eg, aquatic/estuarine/marine). Prey species (oysters, mussels, clams, blood arks [Anadara ovalis], whelks [Busycon carica], false angel wings [Petricola pholadiformis]) were similar in water content to vertebrate prey, moderate to high in protein, and moderate to low in crude fat. Ash and macronutrient concentrations in prey species were high compared with requirements of carnivores or avian species. Prey items analyzed appear to meet nutritional requirements for oystercatchers, as estimated by extrapolation from domestic carnivores and poultry species; excesses, imbalances, and toxicities—particularly of minerals and fat-soluble vitamins—may warrant further investigation.

The prevalence of atherosclerosis is high in the captive psittacine population and increases with age and female sex. The genera Psittacus, Amazona, and Nymphicus are predisposed to atherosclerosis, whereas the genera Cacatua and Ara are less susceptible. Plasma cholesterol and lipoprotein abnormalities have been suggested as risk factors in the development of atherosclerosis as observed in mammals. To investigate whether the psittacine genera susceptibility to atherosclerosis and the known risk factors of age and sex could be associated with differences in the lipid profile, a retrospective analysis was conducted on blood lipid values from 5625 birds. Prevalence values were obtained from a previously published, large, case-control study and were compared with identified trends in plasma lipid profiles. Genus-specific differences were identified in plasma total cholesterol values that corresponded to observed trends in the prevalence of clinically important atherosclerotic lesions, which were also highly correlated. The effect of age was significant but was mild and may not account for the dramatic increase in atherosclerosis prevalence observed with age. In addition, Quaker parrots (Myiopsitta monachus), which were used as experimental models for psittacine atherosclerosis and dyslipidemia, were found to have the highest values in all lipid profile parameters. The results of this study suggest that the differences observed in prevalence among species of the psittacine genera may partly be explained by differences in plasma total cholesterol levels. Results also support the use of Quaker parrots as models for studying atherosclerosis and dyslipidemia.

A 16-year-old female umbrella cockatoo (Cacatua alba) was presented for a fluctuant, right-sided cervical mass that extended from the caudolateral edge of the right mandible to the coelomic inlet. Results of initial diagnostic tests were consistent with a cystic mass containing hemorrhage. Surgical exploration and removal of the mass was done, but because the hyoid apparatus was incorporated in the base of the cyst, complete surgical excision was not possible. Histopathologic results were consistent with a branchial cyst with carcinoma. Five months after surgery, the cockatoo exhibited intermittent periorbital swelling and epistaxis, and cytologic results of a fluid aspirate from the right infraorbital sinus were consistent with carcinoma. Results of magnetic resonance imaging revealed extensive abnormal T2 and short-tau inversion-recovery hyperintense tissue associated with the right side of the head and neck, infiltrating between muscle planes and extending into the right retro-orbital tissue and nasal cavity. At 7 months after surgery, the bird was severely dyspneic and was euthanatized. To our knowledge, this is the first report describing the diagnosis, management, and histologic characteristics associated with a branchial cyst with carcinoma in an animal.

A juvenile racing pigeon (Columba livia) was presented with drooping of the wing and inability to fly. On physical examination, the right shoulder joint was swollen. The pigeon was euthanatized and submitted for necropsy. An excessive amount of fibrin was present in the canalis triosseus with severe arthritis of the affected shoulder joint. A pure growth of Mycoplasma-like colonies was obtained on microbiological culture of the shoulder joint. A 16S ribosomal RNA gene-specific polymerase chain reaction assay was performed on the isolate and revealed 100% similarity with Mycoplasma columbinum. Although infectious arthritis in homing pigeons is primarily associated with paratyphoid and Streptococcus gallolyticus infection, clinical practitioners should consider the potential role of Mycoplasma columbinum in arthritis in pigeons.

A 28-year-old, female umbrella cockatoo (Cacatua alba) was evaluated because of lethargy, anorexia, regurgitation, and coelomic swelling of 6 month's duration, which corresponded to cessation of egg laying. Radiographs and ultrasound examination demonstrated extensive deposits of coelomic fat and an enlarged oviduct. Exploratory celiotomy demonstrated copious amounts of firm, nodular fat completely surrounding the gastrointestinal tract, resulting in extensive chronic adhesions between intestinal loops. Free yolk was present in the cranial left coelom, yolk coelomitis was diagnosed, and a salpingohysterectomy was performed. Two days after surgery, the bird stopped passing feces and began regurgitating after eating, and a colonic obstruction was demonstrated via contrast radiography. Euthanasia was elected, and necropsy revealed an obstruction of the distal colon caused by extraluminal compression by adhesions of firm, nodular fat. Histologic examination demonstrated extensive fat necrosis with granulomatous inflammation, characterized by cords of necrotic fat surrounded by multinucleated giant cells and epithelioid macrophages with scattered lymphocytes and plasma cells and rare heterophils. The clinical signs, gross lesions, and histologic lesions are characteristic of massive fat necrosis (lipogranulomatosis) in ruminants and mesenteric panniculitis in humans and companion mammals. This is the first report, to our knowledge, of this disease in psittacine birds.