This investigation assessed the cardiopulmonary performance, core body temperatures, and arterial blood gases of Hispaniolan Amazon parrots (Amazona ventralis) during 60 minutes of isoflurane anesthesia, using the Hallowell EMC Anesthesia WorkStation (AWS) in combination with controlled intermittent positive pressure ventilation (C-IPPV) or a nonrebreathing system (Bain circuit) with spontaneous ventilation (SV) (n = 6 birds/group). Direct arterial blood pressures, arterial blood gases, end-tidal carbon dioxide (ETco₂), end-tidal isoflurane concentration, heart rates, respiratory rates, and esophageal temperatures were monitored during a 60-minute period of isoflurane anesthesia. Compared with baseline measurements and SV, C-IPPV significantly decreased Paco₂ and increased pHa but did not significantly reduce mean arterial blood pressure. No significant difference in esophageal temperature was observed between the birds receiving C-IPPV and those breathing spontaneously on the Bain circuit. The PaCO₂-ETco₂ gradient was significantly greater in birds receiving SV compared with birds receiving C-IPPV. According to the measured parameters, there were neither deleterious effects nor any apparent advantages associated with positive pressure ventilation. The Hallowell EMC AWS appears to be safe and effective when anesthetizing small birds and will be particularly useful during anesthetic periods when positive pressure ventilation is indicated.

Screening methods are needed for immediate field assessment of affected seabirds during oil spills. We compared the accuracies of 4 handheld blood glucose monitors—Accu-Chek Advantage, Glucometer Elite, Precision QID, and Sure Step—with that of Chemstrip bG for blood glucose determination in seabirds. Study subjects were 44 healthy, adult rhinoceros auklets (Cerorhinca monocerata) housed at a wildlife health center. Handheld monitors were at least as accurate as the commonly used Chemstrip bG method in estimating plasma blood glucose concentrations, although the glucose measurements were significantly lower (P < .05), averaging 33% lower, than those determined by the chemistry reference laboratory. Costs of monitors and test strips were similar, but the Accu-Chek Advantage and Precision QID monitors were the easiest to use and gave reliable glucose measurements (coefficients of variation, <7%). These 2 monitors were used in subsequent evaluations of the effect of anticoagulants and the effect of time interval between sample collection and blood glucose determination. Storage of blood in heparin was preferable to ethylenediamine tetra-acetic acid because it did not significantly (P > .05) alter blood glucose values. Storage of blood for up to 4 hours in a heparinized Microtainer tube at room temperature also produced minimal changes in glucose concentration. We found that electronic, handheld blood glucose monitors underestimate blood glucose concentrations of rhinoceros auklets by 33% in comparison with reference values. However, these monitors are reliable, give results comparable with the Chemstrip bG, and are potentially useful tools for screening purposes in the field during an oil spill.

Enrofloxacin is commonly used to treat bacterial infections in psittacine birds. Enrofloxacin is most effective if dosed per os or by injection, but can be delivered via medicated drinking water. The purpose of this project was to measure the plasma concentrations of enrofloxacin achieved by offering drinking water medicated with an injectable enrofloxacin formulation at 200 mg/L to 16 psittacine birds for 10 days. The birds included 6 cockatoos (Cacatua species), 4 conures (Aratinga species), 2 Senegal parrots (Poicephalus senegalus), 2 red-shouldered macaws (Ara nobilis), and 2 grey parrots (Psittacus erithacus). The injectable formulation was selected because it is readily available in most veterinary hospitals. Blood samples for plasma enrofloxacin and ciprofloxacin assay were collected at 1600–1730 hours on treatment days 2 and 4 and 0830–1000 hours on days 6 and 8. Mean plasma enrofloxacin concentrations (± SD) ranged from 0.11 ± 0.05 to 2.00 ± 1.43 μg/ml for each bird and were 0.40 μg/ml or less for 14 of 16 birds. Ciprofloxacin concentrations were below the limits of detection for all but 2 samples. This study shows that water medicated with the injectable formulation of enrofloxacin at 200 mg/L maintains plasma concentrations in psittacine birds that are adequate only for treating systemic infections caused by highly susceptible bacteria.

This paper reports on the anesthesia and liver biopsy techniques used in adult and nestling pigeon guillemots (Cepphus columba) to test for continued exposure to residual crude oil in the marine environment. Populations of pigeon guillemots have declined significantly in Prince William Sound, Alaska, USA, possibly because of residual effects of crude oil in the environment after the Exxon Valdez oil spill in March 1989. Measurement of hepatic cytochrome P450 1A (CYP1A) is currently the best way to assess crude oil exposure from food sources; however, lethal sampling to obtain adequate liver tissue was not desirable in this declining population of birds. As part of a larger study to identify factors limiting the recovery of pigeon guillemots and other seabird populations, we surgically collected liver samples from adult and nestling guillemots to provide samples for measurement of hepatic CYP1A concentrations. Results from the larger study were reported elsewhere. Liver samples were taken from 26 nestling (1998) and 24 adult (1999) guillemots from a previously oiled site (Naked Island; 12 chicks, 13 adults) and from a nonoiled site (Jackpot Island/Icy Bay; 14 chicks, 11 adults). The birds were anesthetized with isoflurane. No surgical complications occurred with any of the birds and all adult and nestling birds survived after surgery to the point of release or return to the nest. Thirteen out of 14 chicks from the Jackpot Island/Icy Bay and 8 out of 12 chicks from Naked Island fledged. Four chicks at Naked Island were depredated before fledging. All adults abandoned their nests after surgery, so the study sites were revisited the following summer (2000) in an attempt to assess overwinter survival of the adults. All but 1 adult biopsied bird at the nonoiled site (Icy Bay) was found renesting, whereas only 2 birds at the previously oiled site (Naked Island) were similarly observed. The percent of 1999 breeders at Naked Island that returned to their nest sites to breed again in 2000 was low at nests of biopsied birds and nonbiopsied birds alike, suggesting that factors other than the surgical procedure were responsible for the low return rate among this group. These survival results provide strong support for using experienced veterinarians for nonlethal invasive sample collection from birds to document exposure to crude oil in the marine environment.

A 16-year-old male cockatiel (Nymphicus hollandicus) was diagnosed with liver disease on the basis of clinical signs, results of biochemical analyses, and radiographic evidence of hepatomegaly. The bird died shortly after a plasma transfusion while it was anesthetized for a liver biopsy. Postmortem examination revealed ascites, which was localized to the right and left ventral hepatic peritoneal cavities, forming discrete fluid-filled sacs around each lobe of the liver. This fluid had mimicked hepatomegaly radiographically; the liver was actually discolored, firm, and shrunken. Light microscopic findings were consistent with hepatic cirrhosis. The etiology of the hepatic cirrhosis was not determined.

A captive, 18-year-old male Nicobar pigeon (Caloenas nicobarica) with a history of intermittent lameness associated with osteoarthritis in the left tarsometatarsal joint was found dead in its enclosure and submitted for postmortem examination. On gross examination, the left adrenal gland was enlarged and histologically was confirmed as a pheochromocytoma (chromaffin cell tumor). When functionally active, pheochromocytomas can cause nonspecific clinical signs associated with the cardiovascular, nervous, urinary, respiratory, and digestive systems. The majority of clinical signs in animals with this tumor are vague and nonspecific, making antemortem diagnosis challenging. Pheochromocytomas are rare tumors in humans (occurring in 0.20–0.04% of all tumors) and even rarer in animals. Only 2 other cases of this tumor in avian species, a budgerigar (Melopsittacus undulatus) and a 14-week-old chicken (suspected case), have been reported.

An oviductal adenocarcinoma containing foci of osseous and myeloid metaplasia occurred in a 6-year-old female cockatiel (Nymphicus hollandicus). The tumor was also associated with medullary and subperiosteal hyperostosis and cyst formation involving the sternum.