Eight captive ostriches (Struthio camelus), ranging in age from 9 to 11 months, were given a combination of medetomidine and ketamine, administered intramuscularly, and propofol, administered intravenously, for induction and maintenance of anesthesia. Medetomidine (80 μg/kg IM) and ketamine (2 mg/kg IM) resulted in profound sedation and sternal recumbency within a mean time of 14.6 ± 10.0 minutes in 6 birds. Two birds remained standing but were moderately sedated. Propofol, used for induction (3 mg/kg IV) and maintenance (0.2 mg/kg/min constant rate infusion) of anesthesia, enabled intubation and provided muscle relaxation sufficient for restraint lasting 30 minutes. Apnea was observed after propofol administration, but spontaneous ventilation resumed within 60 to 90 seconds. All birds were bradycardic throughout the anesthetic event. Both the heart rate and the cloacal body temperature decreased significantly at 25 and 30 minutes, respectively, after induction. By 5 minutes after induction, the respiratory rate increased significantly and remained high throughout the remainder of the 30-minute evaluation period. During the anesthetic period, systolic, mean, and diastolic blood pressures, as well as arterial pH, arterial oxygen and carbon dioxide partial pressures, and end tidal carbon dioxide partial pressure showed no significant changes. The relative arterial oxygen saturation (SpO₂) was significantly elevated at 15, 25, and 30 minutes after induction. The SpO₂ was less than 90% at 2, 5, 10, and 20 minutes after induction; however, arterial blood gas analysis indicated adequate arterial oxygenation. Anesthetic reversal with the α₂-antagonist atipamezole (400 μg/kg, one half IV and one half SC) was smooth and resulted in a mean recovery time of 21.0 ± 7.3 minutes. The combination of IM medetomidine-ketamine and IV propofol used in this study proved to be effective for sedation as well as the induction and maintenance of anesthesia in captive ostriches.

In mammals, medetomidine causes reliable sedation and can be quickly and smoothly antagonized by atipamezole, allowing smooth and rapid recovery. However, doses of up to 1 mg/kg of medetomidine reportedly do not immobilize avian species. In this study, the sedative and cardiopulmonary effects of medetomidine administered intramuscularly was evaluated in 2 dosage groups (1.5 mg/kg and 2 mg/kg) of 4 domestic pigeons (Columba livia) each and 2 dosage groups (1.5 mg/kg and 2 mg/kg) of 2 yellow-crowned Amazon parrots (Amazona ochrocephala ochrocephala) each. Ten minutes after medetomidine injection, the reflex score of anesthetic level was determined in each bird, and the heart and respiratory rates were measured while birds were manually restrained. Results were compared with values obtained before sedation and 5 minutes after atipamezole injection. Although all birds showed signs of sedation, a desired reflex score for sedation was not obtained in all birds. The reflex score of sedation in domestic pigeons receiving 2 mg/kg medetomidine was not significantly lower than that of birds receiving 1.5 mg/kg, indicating no increase in sedation with the higher dose. However, the Amazon parrots that received the higher dose had a significantly lower reflex score than those that received the lower dose, indicating an increase in sedation with the higher dose. In both species and at both doses, a decrease in heart rate and in respiratory rate were observed, with no significant differences between the groups. Antagonism with atipamezole at both 2.5 and 5 times the medetomidine dose caused a smooth, rapid, and complete recovery. In these 2 species, although medetomidine did have a sedative effect and was reliably antagonized, it did not reliably induce a desirable state of sedation, even at the high doses investigated. Therefore, medetomidine alone as an anesthetic agent is not recommended for routine use in avian practice.

The pharmacokinetic disposition of itraconazole in plasma and tissues was evaluated in a multiple dose study using 11 nonreleasable red-tailed hawks (Buteo jamaicensis). An itraconazole solution was administered by gavage at a dosage of 5 mg/kg in 4 hawks and 10 mg/kg in 7 hawks once daily for 15 days. On days 1 and 14, blood samples were obtained at 1, 8, 16, and 24 hours after itraconazole administration. The hawks were killed on day 15, and samples of air sac, brain, kidney, liver, lung, and small intestine were retrieved. High-pressure liquid chromatography was used to measure the concentration of the parent drug, itraconazole, and its active metabolite, hydroxyitraconazole, in plasma and tissues of each hawk. Concentrations represent point-in-time values. Results suggest that hawks gavaged with itraconazole at 10 mg/kg once daily will reach steady state plasma concentrations of itraconazole and hydroxyitraconazole within 2 weeks. Although plasma concentrations were lower than those reported in parrots and pigeons, concentrations of both itraconazole and hydroxyitraconazole in organs other than the brain were comparable among species of birds.

Chlamydiosis is an important cause of morbidity and mortality in cockatiels (Nymphicus hollandicus); however, little published information is available regarding effective treatment options for this species. This preliminary study was conducted to determine if adequate plasma concentrations of doxycycline, the antibiotic of choice for treating chlamydiosis in pet birds, could be achieved in cockatiels by using different methods of administration. Doxycycline hyclate was administered to 5 groups comprising 3 to 6 birds each by intramuscular injection (100 mg/kg IM every 10 days for 5 injections) or by mixing with drinking water (0.28 or 0.83 mg/ml), seeds (500 mg/kg wet weight), or mash (1000 mg/kg). Three additional groups of birds received unmedicated food and water and served as controls. Plasma doxycycline concentrations were measured periodically during the 45-day trial. Birds given doxycycline by intramuscular injection had variable, localized tissue reactions and a mean trial plasma concentration <1 μg/ml, the value considered therapeutic for treating chlamydiosis. Birds that received doxycycline in drinking water and in seeds maintained group mean doxycycline concentrations >1 μg/ml. Birds that received doxycycline in mash had high plasma doxycycline concentrations and showed severe clinical illness, suggesting doxycycline toxicosis; drug administration was discontinued on day 3. Therefore, in this study, drinking water and seeds were effective vehicles for doxycycline administration to clinically healthy cockatiels under controlled conditions. However, mash combined with doxycycline resulted in severe toxicosis, whereas doxycycline hyclate by intramuscular injection did not achieve desired therapeutic plasma concentrations. Further studies are needed to examine efficacy and safety of food- and water-based doxycycline regimens in clinically ill birds and those housed under different environmental conditions.

A ring-necked pheasant (Phasianus colchicus), a rock dove (Columba livia), and a red-tailed hawk (Buteo jamaicensis) were each presented with a large soft tissue wound on the head with exposed skull. Each bird was treated with wound debridement, removal of necrotic bone, and grafting of a single pedicle advancement flap from the adjacent dorsal cervical skin. Wounds in the pheasant and hawk healed without complication. In the rock dove, the initial flap necrosed, but a second single pedicle advancement flap, elevated from the dorsal cervical skin, was successful. The final result in all 3 birds was complete coverage of the defect with full-thickness skin. In birds, use of single pedicle advancement flaps mobilized from dorsal cervical skin may expedite healing of large soft tissue wounds of the head, especially when the skull is exposed.

A syndrome of sudden death in captive orange-bellied parrots (Neophema chrysogaster) was associated with zinc toxicosis. A total of 77 birds was examined, with most being found dead in good flesh with no histologic lesions. Affected birds had a mean zinc level of 154.3 μg/g in the kidneys, 289.8 μg/g in the liver, and 723.6 μg/g in the pancreas. These values were compared with a mean zinc level of 65.3 μg/g in kidneys of unaffected birds. Additionally, the fertility rate in this population of captive parrots was 54% in 1995–96, 59% in 1996–97, and 66% in 1997–98. After all galvanized wire was replaced with nylon mesh before the 1998–99 breeding season, the fertility rate increased to 86%. Ingestion of zinc can affect the central nervous system, and birds with neurologic signs may have died as a result of colliding with walls or structures in the aviaries. The absence of histologic lesions usually associated with zinc toxicosis in affected birds may have been related to acute head trauma as the cause of death.

Infections with filarial nematodes are well documented in numerous orders of birds worldwide. The filarial nematode Paronchocerca ciconarum has been found within the heart and pulmonary vessels of saddle-billed storks (Ephippiorhynchus senegalensis), as well as other species of African storks. Until now, identification of microfilariae on direct smears of circulating blood has been the only antemortem method reported to successfully diagnose cardiovascular filarial infections in birds. We report the use of a commercial test kit for canine heartworm (Dirofilaria immitis) antigen to aid in detecting adult P ciconarum infection in 2 saddle-billed storks, 1 at necropsy and 1 antemortem. Results of this test were positive for both birds. Direct blood smears and blood filtration tests were also used to identify circulating microfilariae. Both birds died because of separate, unrelated causes but had adult P ciconarum filariae in the pulmonary arteries and, in 1 stork, the right ventricle. On the basis of our findings in these 2 storks, testing for canine heartworm antigen, in conjunction with a blood filtration test and stained blood smear of peripheral blood, may improve detection of cardiovascular filarial infections in birds.

A black-masked blue lovebird (Agapornis personata) was presented because of lethargy and poor feathering. Examination revealed multiple firm swellings of the wings and sternum. Because of the bird's general condition and the number and size of the bony lesions, successful treatment was unlikely, and the bird was euthanatized. Result of histopathologic examination revealed the masses to be multiple exostoses.