Florina S. Tseng

PHARMACOKINETICS OF BUPRENORPHINE AFTER SINGLE DOSE SUBCUTANEOUS ADMINISTRATION IN RED-EARED SLIDERS (TRACHEMYS SCRIPTA ELEGANS)

Abstract Buprenorphine, a μ opioid receptor agonist, is expected to be a suitable analgesic drug for use in reptiles. However, to date, dosage recommendations have been based on anecdotal observations. The aim of this study was to provide baseline pharmacokinetic data in red-eared sliders (Trachemys scripta elegans) targeting a plasma level of 1 ng/ml reported effective for analgesia in humans. Serial blood samples were taken after subcutaneous injection of buprenorphine, and plasma buprenorphine levels were measured by radioimmunoassay. Pharmacokinetic parameters of a lower dose (0.02 mg/kg) injected into the forelimb were compared with a higher dose (0.05 mg/kg) given in the same forelimb as well as a lower dose (0.02 mg/kg) given in the hind limb of the same animals with 2 wk between studies. After administration of 0.05 mg/kg in the front limb, 85% of animals maintained the minimum effective plasma level for 24 hr, while only 43% of animals maintained this level after 0.02 mg/kg. After hind limb injection at 0.02 mg/kg, maximum plasma concentrations and areas under the buprenorphine concentration-time curve were less than 20% and 70%, respectively, of values after forelimb injection, consistent with substantial first pass extraction by the liver. Furthermore, a secondary rise in the buprenorphine level was found after having only a hind limb injection, probably from enterohepatic recirculation of glucuronidated drug. In conclusion, buprenorphine dosages of at least 0.075 mg/kg s.i.d. should be appropriate for evaluation of analgesia efficacy, and front limb administration may be preferable to hind limb administration for optimal drug exposure.

An experimental soft-release of oil-spill rehabilitated American coots (Fulica americana): II. Effects on health and blood parameters

The Unocal-Metrolink oil spill of 21 February 1995 resulted in approximately 7800 barrels of San Joaquin crude oil being deposited into the San Gabriel River in Huntington Beach, CA, USA. In order to determine long-term pathological effects of oil exposure and rehabilitation, hematological and serum biochemical parameters for both rehabilitated (RHB) American coots (Fulica americana) and reference (REF) coots were examined every 3-4 weeks (56, 81, 108 and 140 days post oil exposure) after birds were cleaned, rehabilitated and soft-released. Most significant differences in monthly comparisons between RHB and REF birds occurred 56 days following oil exposure. Total white blood cell (WBC) count, albumin:globulin (A:G) ratio and calcium concentration were higher in RHB birds compared to REF birds 56 days post oil exposure. In addition, mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase and creatine kinase activities, and creatinine, total protein (TP) and globulin concentrations were lower in RHB birds. Blood results from 56 days post oil exposure for RHB coots which subsequently died were compared to blood results from days 108 and 140 for REF coots which survived. Oiled and rehabilitated birds which died had significantly higher WBCs, packed cell volume, TP and globulin concentrations, and lower A:G ratio, MCH, MCHC, glucose and sodium concentrations compared to REF birds which survived. Blood result differences detected at 3-4-week intervals between RHB and REF survivors, and differences detected between RHB coots which died and REF coots which survived, suggested that RHB coots developed an inflammatory response (infectious or non-septic) and, concurrently, may have experienced decreased immune responsiveness. Additionally, RHB coots experienced either an iron (Fe) utilization or Fe metabolism problem. These pathophysiological mechanisms were consistent with increased hemosiderin (stored Fe) present in the liver, spleen and kidney of necropsied RHB birds, and may have contributed to RHB coot mortality. When blood parameter differences were examined for their impact on survival time, it was determined that RHB coots had shorter survival times if they had very high cholesterol (> or =449 mg/dl) or chloride (> or =110 MEQ/l) concentrations on day 56 post oil exposure. Interestingly, the lack of differences between RHB and REF coots from day 81 through day 140 suggested that, from a hematologic and clinical chemistry perspective, coots which were oiled, rehabilitated, released and survived at least 3.5 months could not be differentiated from wild (REF) coots. From these findings it appears that blood analysis, coupled with post-release survival data, may help discern reasons for increased mortality of oiled and rehabilitated birds, compared to non-oiled reference birds.

Advances in Oiled Bird Emergency Medicine and Management

Abstract Oil spills affect aquatic birds on individual, population, and ecosystem levels. Communities have responded to environmental accidents and have cared for oiled birds for as long as the damaging effects of oil exposure have been realized. Not until the Exxon Valdez disaster occurred, however, was there the political climate necessary to facilitate and fund organized oiled wildlife responses in the United States. Federal and California law now supports the infrastructure necessary to respond rapidly and efficiently to oil spills affecting wildlife. This improved infrastructure has resulted in access to appropriately designed and equipped facilities, trained staff and volunteers, and research improving medical management and bird survival.

Diagnosis and Treatment of Secondary Anticoagulant Rodenticide Toxicosis in a Red-tailed Hawk (Buteo jamaicensis)

ABSTRACT Anticoagulant rodenticides inhibit the activation of vitamin K–dependent clotting factors, resulting in fatal hemorrhage. Nontarget species are exposed to these rodenticides primarily by direct consumption of baits or secondarily by consumption of poisoned prey. The diagnosis of anticoagulant rodenticide toxicosis is more challenging in birds than in mammals because of the limited availability of laboratory tests to evaluate avian coagulation. In addition, the presenting signs in birds may differ from those commonly seen in mammals. Treatment for acute blood loss and therapy with vitamin K1 can result in a favorable outcome in birds. This report describes the presenting signs, diagnosis, and successful treatment of a red-tailed hawk (Buteo jamaicensis) with secondary anticoagulant rodenticide toxicosis.

Description of Novel Babesia Species and Associated Lesions from Common Murres (Uria aalge) from California

Abstract A novel Babesia species is described from blood collected from 3 common murres (also known as common guillemots) (Uria aalge) from California. This is the first report of a Babesia species from the Alcidae and the second from the Charadriiformes. Babesia uriae n. sp. is morphologically similar to several other avian Babesia species but can be differentiated from Babesia bennetti, the only other species from a host in the Charadriiformes, by size of round and amoeboid forms. Phylogenetic analysis of near–full length 18S rRNA, ITS-1, 5.8S rRNA, and ITS-2 sequences indicated that the Babesia sp. from the common murre is closely related to Babesia poelea, a parasite of brown boobies (Sula leucogaster).

Considerations in Care for Birds Affected by Oil Spills

Oil spills occur on a worldwide basis from a variety of sources, including tanker ruptures, pipeline breaks, and oil well explosions. In addition to these large-scale events, a smaller number of birds are affected on a daily basis from both petroleum and vegetable oil sources. The external effects of oil on wildlife include feather contamination resulting in loss of insulation, loss of buoyancy in water, and loss of flight ability, as well as skin and ocular burns of varying severity. Internal effects result from inhalation and ingestion of toxic components that lead to pneumonia, gastrointestinal disturbances, hemolytic anemia, immune suppression, and organopathy. The rehabilitation of oiled wildlife involves field stabilization, correction of underlying physiological abnormalities before washing, proper washing and rinsing of all contaminants, and assessment of set criteria before release. All wildlife care during an oil spill response is conducted in cooperation with state and federal trustee agencies and includes the collection of appropriate samples for legal documentation of affected individuals.

BASELINE HEALTH PARAMETERS AND SPECIES COMPARISONS AMONG FREE-RANGING ATLANTIC SHARPNOSE (RHIZOPRIONODON TERRAENOVAE), BONNETHEAD (SPHYRNA TIBURO), AND SPINY DOGFISH (SQUALUS ACANTHIAS) SHARKS IN GEORGIA, FLORIDA, AND WASHINGTON, USA

Sharks are of commercial, research, conservation, and exhibition importance but we know little regarding health parameters and population status for many species. Here we present health indicators and species comparisons for adults of three common wild-caught species: 30 Atlantic sharpnose sharks (Rhizoprionodon terraenovae) and 31 bonnethead sharks (Sphyrna tiburo) from the western Atlantic, and 30 spiny dogfish sharks (Squalus acanthias) from the eastern Pacific. All animals were captured during June–July 2009 and 2010. Median values and preliminary reference intervals were calculated for hematology, plasma biochemistry, trace nutrients, and vitamin A, E, and D concentrations. Significant differences, attributable to physiologic differences among the species, were found in the basic hematologic and plasma biochemistry variables. Significant species differences in arsenic and selenium plasma concentrations were found and appear to coincide with diet and habitat variability among these three species. Vitamin E was significantly higher in the bonnethead shark, again related to the foraging ecology and ingestion of plant material by this species. The Atlantic sharpnose had significantly higher vitamin A concentrations, supported by the higher proportion of teleosts in the diet. Vitamin D was below the limit of quantification in all three species. These preliminary reference intervals for health variables can be used to assess and monitor the population health and serve as indicators of nutritional status in these populations of wild elasmobranchs.

Sepsis and disseminated intravascular coagulation in an eastern spiny softshell turtle (Apalone spinifera spinifera) with acute mycobacteriosis.

Abstract An adult, captive eastern spiny softshell turtle (Apalone spinifera spinifera) was examined for a 4-day history of lethargy and plastron discoloration. The turtle was obtunded and had pale mucous membranes, hemorrhagic nasal discharge, and petechiae on all limbs. The turtle was euthanized due to its grave condition. Necropsy revealed hemorrhagic coelomic effusion, petechiae on the serosal surfaces of the intestinal tract, and bilaterally hemorrhagic lungs. Histologic examination revealed numerous emboli of bacteria associated with fibrinocellular thrombi throughout the blood vessels of multiple tissues. The bacteria in the thrombi were slender bacilli that stained intensely acid fast. Culture of the coelomic fluid yielded Mycobacterium chelonae. Although mycobacteriosis in reptiles is typically a chronic, granulomatous disease, this case demonstrates that mycobacteriosis should be considered in reptiles presenting with acute, nongranulomatous disease. This case also describes clinically apparent hemorrhage due to disseminated intravascular coagulation, which is rarely described in chelonians.

Decreased Hematocrits in Common Terns (Sterna hirundo) Exposed to Oil: Distinguishing Oil Effects from Natural Variation

Abstract. Hematocrits were measured in Common Terns (Sterna hirundo) (n = 75) that were exposed to oil from a spill in Buzzards Bay, Massachusetts, USA, in 2003, and that laid eggs 17–39 days following the spill. Comparative data were obtained in three pre- and two post-spill years and from three unoiled reference sites. In non-spill years, annual means of hematocrit varied in parallel with breeding performance. Hematocrits were lower (mean 45.3, n = 75) and more variable in the oil spill year than in non-spill years, and 20% of birds sampled were anemic (hematocrit < 41.7). However, hematocrits were almost as low (mean 46.4, n = 44) in 2002, a year with naturally adverse conditions. In 2002, hematocrits and body-masses were depressed following two storms and recovered in parallel following the storms; hematocrits were positively correlated with body-mass and ambient temperature and negatively correlated with wind speed. In contrast, in 2003 hematocrits were negatively correlated with body-mass and temperature and positively correlated with wind speed. Hematocrits were very low (mean 39.8, n = 15) when birds were first sampled 20–23 days after the spill and recovered toward normal levels by day 39 (mean 49.4, n = 14). Reduced hematocrits can be a useful indicator of sublethal oil intoxication, especially in females, provided that they are not associated with low body-masses or adverse weather. Measuring hematocrits could be useful for rapid screening of populations sublethally exposed to oil.

A Technique for Evisceration as an Alternative to Enucleation in Birds of Prey: 19 Cases

Abstract: Ocular trauma is common in birds of prey presented to wildlife clinics and rehabilitation centers. Enucleation is the procedure most commonly described for treatment of end-stage ocular disease or chronically painful eyes in birds; however, there are several disadvantages and risks to this procedure. While evisceration has been suggested as an alternative, it has not been described for multiple cases or with long-term follow-up data in birds of prey. This report details an evisceration technique performed in 5 captive birds of prey of 4 different species (1 eastern screech owl [Megascops asio], 1 great horned owl [Bubo virginianus], 2 red-tailed hawks [Buteo jamaicensis], and 1 bald eagle [Haliaeetus leucocephalus]) with long-term follow-up information. In addition, this report describes 14 cases of free-living owls of 3 different species (1 great horned owl, 4 barred owls [Strix varia], and 9 eastern screech owls) on which this technique was performed from 2004 to 2011 and which were subsequently released to the wild. Because of the limited risk of complications and the less-severe disruption of facial symmetry, which may be particularly important in owls that are candidates for release to the wild, evisceration should be considered over enucleation in birds of prey that require surgical intervention for the management of severe sequelae to ocular trauma.