Birds of prey are found increasingly in captive situations. When sick, these animals show only very subtle signs of disease, making the detection of disease difficult. For this reason, the analysis of hematologic parameters is a very useful technique for the avian veterinarian. However, birds are most frequently transported to the veterinary clinic for a health check-up. This study investigates the effects of transport-related stress on heterophil and lymphocyte morphology and hematologic parameters of peregrine falcons (Falco peregrinus) and Harris's hawks (Parabuteo unicinctus). Twelve birds of each species, all adults, mixed males and females, were analyzed. Each group of 12 was comprised of 6 trained (accustomed to being transported) and 6 untrained birds. Samples of blood were taken from all birds in their place of origin and again 1 week later after 1 hour (35 km) of transport. Both samples were taken in similar conditions (eg, time of day, duration after feeding, environmental temperature, sample handling) so that any variation would be caused only by transport-related factors. Both untrained groups showed a significant (P < .05) increase in the heterophil/lymphocyte ratio (H/L). Whereas untrained peregrines showed no other significant change, untrained Harris's hawks had a significant leukopenia, lymphopenia, and eosinopenia. Trained Harris's hawks showed a significant monocytosis, whereas trained peregrines showed no significant change. Transport had no apparent influence on heterophil or lymphocyte morphology. Although the difference between pre- and posttransport was significant in some parameters, all values in the 4 groups remained within the reference ranges for the species. Therefore, we can conclude that 1-hour transport for trained or untrained members of these 2 species to a clinic need not be factor that requires the clinician's consideration when interpreting a hematologic sample. However, the 2 species reacted differently to transport. Further studies on other species are suggested. The H/L ratio is proposed as the most sensitive measure of stress response in the blood picture of raptors, and possible uses are suggested.

Ten sulphur-crested cockatoos (Cacatua galerita) were anesthetized twice, 2 weeks apart, to evaluate the effects on respiratory function of endotracheal (ET), caudal thoracic (CT) air sac, and clavicular air sac administration of isoflurane anesthesia. Four administration methods were evaluated by administering anesthetic gases through either the ET tube or the air sac as an open or closed system. Respiratory function was monitored by arterial and venous blood gas determination, gas-in-gas determination of both ET tube and air sac gases, and spirometry. Both ET tube and CT air sac administration provided a reliable method of maintaining anesthesia and resulted in minimal alteration in respiratory function. Blood pH, partial pressure of carbon dioxide (Pco₂), bicarbonate, total carbon dioxide, and base excess were not significantly altered by CT air sac administration. Increased partial pressure of oxygen and oxygen saturation were evidence of hyperoxia. CT air sac Pco₂ decreased to 12.7 ± 7.9 mm Hg with CT administration, and this was sufficient to maintain spontaneous respiratory movements. Spirometry demonstrated maintenance of tidal and minute volumes with each administration method despite apparent reduction in visible respiratory movements. Clavicular air sac administration was not successful in providing ventilation or maintaining anesthesia. Despite the demonstrated ability to flush a bolus of gas through this air sac and out the ET tube, no spontaneous ventilation was detected in this air sac in either an open or closed system, preventing delivery of sufficient isoflurane to maintain anesthesia.

Contrast radiography with positive-pressure insufflation (PPI) at 20 cm of water pressure was evaluated for safety and analyzed for potential diagnostic use in 6 male northern pintails (Anas acuta). Ducks were anesthetized for either 2 or 3 procedures, 1 week apart, then euthanized and necropsied after the final procedure. Air sac areas on survey and PPI radiographs were measured to calculate average percent increase of visible air sac area after PPI. No clinical complications resulted from PPI procedures. Birds recovered quickly without respiratory distress. No gross or microscopic respiratory lesions associated with PPI were identified at necropsy. Average percent increases in air sac areas resulting from PPI on lateral and ventrodorsal radiographs were 79% and 90%, respectively. As judged subjectively by attending clinical veterinarians, cardiohepatic, air sac, lung, renal, gastrointestinal, vertebral, and testicular margins and boundaries were more distinct as a result of PPI. PPI in an avian patient using air as a negative contrast medium is a safe, effective technique that potentially allows increased radiographic diagnostic capability.

Active warming of birds under general anesthesia is required to prevent hypothermia and its life-threatening consequences. The ability of a forced-air warming system to provide thermal homeostasis during isoflurane anesthesia of 10 Hispaniolan Amazon parrots (Amazona ventralis) was compared to a circulating-water blanket and an infrared heat emitter. Each bird was anesthetized once weekly for a 60-minute trial of each of 5 methods: no thermal support (control), surgical drape only, towel-covered circulating-water blanket and drape, infrared heat emitter and drape, and forced-air warmer and drape. An esophageal thermometer was used to measure the bird's core body temperature during each trial, and the temperature of the surgical area immediately adjacent to the bird as well as the ambient room temperature were also recorded. Time zero was 5 minutes after intubation. None of the warming methods prevented a significant decrease in core body temperature measured during the 60-minute trial period. A significant decrease in core body temperature was observed within 15 minutes with all warming methods except the forced-air warmer, which prevented a significant decrease in temperature before 30 minutes. Even though the forced-air warmer did not prevent a drop in core body temperature during the last 30 minutes of the trial, the temperature remained within the clinically acceptable range of 38.3–40.6°C. A significant increase occurred in the temperature of the surgical area immediately adjacent to each bird from 15 to 60 minutes for all warming methods, but the magnitude of the increase was not different among modalities. The forced-air warming system proved superior to traditional heating methods in restricting heat loss and is an effective modality for the prevention of hypothermia during isoflurane anesthesia of Hispaniolan Amazon parrots in clinical practice or a research setting.

This study reports the content of iron and selected minerals from food items commonly ingested by keel-billed toucans (Ramphastos sulfuratus) in their native habitat in Belize, Central America. These same minerals were analyzed and compared with those found in a commercially prepared diet that was formulated to be low in iron. Seven of the food items collected from the wild had a total iron content ≤ 50 μg/g, whereas the remaining food items were ≤150 μg/g (except for 1 plant item). In contrast, the low-iron diet contained 210 μg/g of iron on a dry-matter basis. This study suggests that iron overload from feeding a commercial diet may contribute to the development of iron storage (disease) in captive toucans and other iron-sensitive species.

The clinical and pathologic findings of 3 houbara bustards (Chlamydotis undulata macqueenii) with tarsometatarsal deformities are presented. These birds were hatched and reared at the National Avian Research Center in the United Arab Emirates as part of its captive breeding program. All 3 birds had short tarsometatarsal bones as a result of chondrodystrophy. Two of these birds developed varus deformities and fused tarsometatarsal trochleae that resulted in swollen intertarsal joints, luxated gastrocnemius tendons, and dislocated phalanges. One bird was euthanized, and the other 2 were excluded from the captive breeding program.

An adult female rainbow lorikeet (Trichoglossus haematodus haematodus) was presented with an acute onset of vomiting and melena. Fecal cytology and fecal Gram stain confirmed the presence of erythrocytes and bacteria morphologically similar to clostridia. Clostridium tertium was cultured from the feces. Leukocytosis with moderate absolute heteropenia, absolute lymphocytosis, and toxic immature heterophils was observed on the complete blood count. Plasma biochemistry analysis included mild hyperuricemia and metabolic alkalosis. The most significant radiographic abnormalities included proventricular filling defects, intestinal dilatation, and gas accumulation in the gastrointestinal tract. All radiographic changes were believed to be secondary to bacterial infection. Clostridial enteritis was tentatively diagnosed and successfully treated with antibiotics and supportive care. Clostridium tertium infection was hypothesized to have originated from the combination of a contaminated water source, a high carbohydrate diet, and a lack of adequate sanitation. No further clinical problem occurred after implementation of husbandry recommendations.

Seven psittacine birds from an aviary of 35 birds developed respiratory disease and died after the premises were cleaned with a commercial solution of undiluted sodium hypochlorite (5% chlorine bleach). Six birds died within 12 days postexposure, and clinical abnormalities were first observed at 6 days. All 7 birds were necropsied and had gross and histopathologic lesions of the trachea, including epithelial deciliation (7/7), ulceration (6/7), squamous metaplasia (5/7), and epithelial hyperplasia (5/7). These tracheal lesions were consistent with inhalation of a noxious agent. Death in these birds was considered to result from hypoxia secondary to blockage of the trachea or pulmonary congestion and, in some cases, sepsis secondary to invasion of bacteria through the altered tracheal mucosa.

A 6-year-old female red lory (Eos bornea) was presented with abdominal swelling and nesting behavior, which could be suggestive of hyperestrogenism. On physical examination, the bird was obese and had a firm palpable mass extending from the keel to the pubic bones. Elevated biochemical analytes included alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and cholesterol. A ventral midline abdominal hernia, severe hepatomegaly, and polyostotic hyperostosis were diagnosed on the basis of whole body radiographs and abdominal ultrasound. The abdominal hernia was reduced successfully through a ventral midline celiotomy. Severe and diffuse hepatic lipidosis with mild biliary hyperplasia was observed histologically from a liver biopsy. Postoperative management consisting of diet modification and increased exercise resulted in a significant decrease in liver size radiographically 6 months after surgery.