Wetlands have long been suspected to be an important reservoir for Pasteurella multocida and therefore the likely source of avian cholera outbreaks. During the fall of 1995–98 we collected sediment and water samples from 44 wetlands where avian cholera epizootics occurred the previous winter or spring. We attempted to isolate P. multocida in sediment and surface water samples from 10 locations distributed throughout each wetland. We were not able to isolate P. multocida from any of the 440 water and 440 sediment samples collected from these wetlands. In contrast, during other investigations of avian cholera we isolated P. multocida from 20 of 44 wetlands, including 7% of the water and 4.5% of the sediment samples collected during or shortly following epizootic events. Our results indicate that wetlands are an unlikely reservoir for the bacteria that causes avian cholera.

An outbreak of epizootic hemorrhagic disease virus, serotype 2 (EHDV-2) was responsible for localized white-tailed deer (Odocoileus virginianus) mortality in Hardy and Hampshire counties, West Virginia (USA), in the summer and fall of 1993. Using available historical data on regional herd immunity, data opportunistically collected during the epizootic, and postepizootic sampling of hunter-harvested deer, we grossly estimate certain epidemiologic parameters and compare findings to a hypothesis about hemorrhagic disease outbreaks in the Appalachian Mountains. During the epizootic, 57.9 km² were actively searched and 228 dead deer were found. Epizootic hemorrhagic disease virus, serotype 2 was isolated from seven of nine deer sampled in Hardy and Hampshire counties. Preepizootic exposure of deer to EHD viruses was unknown, but available data suggest that it was negligible. The geographic distribution of the outbreak was defined by plotting the locations of dead deer found during the outbreak, as well as the locations of deer harvested by hunters after the outbreak that had antibodies to EHDV-2 on a map sectioned into 16.65 km² rectangular sections. Sections that included one or more dead deer or hunter-harvested deer with antibodies to EHDV-2 were included in the defined outbreak area. Postoutbreak sampling revealed monospecific EHDV-2 antibodies in 12% of deer harvested by hunters within the defined outbreak area. Based on the available data and accepting certain assumptions, gross calculations suggest that this outbreak appears to have been isolated and probably killed a high percentage of the deer that were infected. This is consistent with the hypothesis that sporadic hemorrhagic disease outbreaks in the Appalachian Mountains are usually localized and severe.

Owing to the rapid decline of the European mink (Mustela lutreola) in France, a national conservation action plan has been initiated, in which scientific research to improve understanding of the causes of the decline is one of the primary objectives. In order to investigate the possible role of Aleutian disease parvovirus (ADV) in decline of the species, a serologic survey was conducted from March 1996 to March 2002 in 420 free-ranging individuals of six species of small carnivores distributed in eight départements of southwestern France. Antibodies to ADV were detected in 17 of 75 American mink (Mustela vison), 12 of 99 European mink, 16 of 145 polecats (Mustela putorius), four of 17 stone martens (Martes foina), one of 16 pine martens (Martes martes), and three of 68 common genets (Genetta genetta). Seroprevalence was significantly higher in American mink than in other species. Seropositive individuals with gamma globulin levels >20% were observed in four European mink, four American mink, two stone martens, and one pine marten. Geographic distribution of positive animals indicates the virus has spread to all areas where European mink are found. Furthermore, a trend of increasing prevalence seems to appear in Mustela sp. sympatric with American mink. Although further investigations are necessary to evaluate the role of ADV in decline of European mink, evidence of the virus in the wild at the levels found in our study has implications for conservation of this species.

Our research has focused on the ecology of commensal populations of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado (USA), in relation to rabies virus (RV) transmission. We captured 35 big brown bats (Eptesicus fuscus) in late summer 2001 and held them captive for 4.8 mo. The bats were initially placed in an indoor cage for 1 mo then segregated into groups of two to six per cage. Two of the bats succumbed to rabies virus (RV) within the first month of capture. Despite group housing, all of the remaining bats were healthy over the course of the investigation; none developed rabies, although one of the rabid bats was observed to bite her cage mates. Reverse transcription–polymerase chain reaction (RT-PCR) and Taqman^® real-time PCR analysis of the RNA derived from the brain tissue, salivary glands, and oral swab samples confirmed RV infection in the dead bats. Rabies virus was also isolated from the brain tissue upon passage in mouse neuroblastoma cells. Nucleotide sequence analysis of the RV nucleoprotein (N) gene showed 100% identity with the N gene sequence of a 1985 E. fuscus isolate from El Paso County, Colorado. Bat sera obtained six times throughout the study were assayed for RV neutralizing antibodies using the rapid fluorescent focus inhibition test. The RV neutralizing activity in the serum was associated with the IgG component, which was purified by binding to protein G Sepharose. Five bats were RV seropositive prior to their capture and maintained titers throughout captivity. Two adult bats seroconverted during captivity. Two volant juvenile bats had detectable RV antibody titers at the first serum collection but were negative thereafter. Four seronegative bats responded to a RV vaccine administration with high titers of RV antibodies. A serologic survey of big brown bats in the roost from which one of the captive rabid bats had originated showed a significant rise in seroprevalence during 2002.

Tilapia (Oreochromis mossambicus) have been implicated as the source of type C toxin in avian botulism outbreaks in pelicans (Pelecanus erythrorhynchos, Pelecanus occidentalis californicus) at the Salton Sea in southern California (USA). We collected sick, dead, and healthy fish from various sites throughout the Sea during the summers of 1999 through 2001 and tested them for the presence of Clostridium botulinum type C cells by polymerase chain reaction targeting the C1 neurotoxin gene. Four of 96 (4%), 57 of 664 (9%), and five of 355 (1%) tilapia tested were positive for C. botulinum type C toxin gene in 1999, 2000, and 2001, respectively. The total number of positive fish was significantly greater in 2000 than in 2001 (P<0.0001). No difference in numbers of positives was detected between sick and dead fish compared with live fish. In 2000, no significant relationships were revealed among the variables studied, such as location and date of collection.

Chytridiomycosis caused by Batrachochytrium dendrobatidis (Chytridiomycota) has been implicated in declines of amphibian populations on four continents. We have developed a sensitive and specific polymerase chain reaction–based assay to detect this pathogen. We isolated B. dendrobatidis from captive and wild amphibians collected across North America and sequenced the internal transcribed spacer regions of the rDNA cassette of multiple isolates. We identified two primers (Bd1a and Bd2a) that are specific to B. dendrobatidis under amplification conditions described in this study. DNA amplification with Bd1a/Bd2a primers produced a fragment of approximately 300 bp from B. dendrobatidis DNA but not from DNA of other species of chytrids or common soil fungi. The assay detected 10 zoospores or 10 pg of DNA from B. dendrobatidis and detected infections in skin samples from a tiger salamander (Ambystoma tigrinum), boreal toads (Bufo boreas), Wyoming toads (Bufo baxteri), and smooth-sided toads (Bufo guttatus). This assay required only small samples of skin and can be used to process a large number of samples.

In two studies conducted from October 1999 to March 2000 and December 2000 to April 2001, adult black bears (Ursus americanus) were orally inoculated with 1.4–3.1×10¹⁰ colony-forming units (CFU) of Brucella abortus strain RB51 (SRB51, n =12) or 2 ml of 0.15 M NaCl solution (saline, n = 11). We did not detect a difference (P>0.05) in antibody titers to SRB51 in serum obtained before vaccination, at 8 wk after vaccination, or at necropsy at 21 or 23 wk after vaccination between SRB51-vaccinated and nonvaccinated bears. The SRB51 vaccine strain was recovered from tissues obtained at necropsy from one of six SRB51-vaccinated bears in study 1, but none of the six SRB51-vaccinated bears in study 2. Vaccination of black bears with SRB51 did not appear to influence (P>0.05) reproductive performance.

Since 1997, numerous Columbian black-tailed deer (Odocoileus hemionus columbianus) in western Washington (USA) have developed a hair loss syndrome that often preceded emaciation, debilitation, pneumonia, and death. To study this syndrome, eight affected free-ranging Columbian black-tailed deer fawns were captured from western Washington in February 1999 to determine the effect of ivermectin treatment. Fecal examinations indicated that the internal parasites were Dictyocaulus viviparus, Parelaphostrongylus sp., Trichuris sp., Moniezia sp., Eimeria spp., and gastrointestinal strongyles. Biting lice (Tricholipeurus parallelus) were observed on all deer, with up to 5 lice/cm² on the index areas counted. Three deer were treated with ivermectin subcutaneously at doses between 0.2 and 1.3 mg/kg of body weight monthly for four consecutive months, and five control deer received no anthelmintic treatment. Complete blood counts, parasite evaluations, weight gains, and hair loss evaluations were used to assess effectiveness of treatment. Two untreated deer died during the experiment compared with no deaths among the three treated deer. Treated deer gained significantly more weight (P<0.05) than the untreated deer (22.4 vs. 12.6 kg, respectively) that survived the experiment, had significantly fewer parasite eggs and larvae (P<0.05) in feces and significantly fewer nematodes (P<0.05) at necropsy, and regrew their hair at a faster rate than untreated deer. Lice and all nematode eggs and larval stages in feces were eliminated or greatly reduced following treatment. On the basis of these data, excessive louse populations, gastrointestinal nematodes, and the lungworms Parelaphostrongylus sp. and D. viviparus, might be important predisposing factors for this hair loss condition and death of affected animals.

Overwinter fawn mortality associated with hair loss syndrome (HLS) is anecdotally thought to be important in declines of Columbian black-tailed deer (Odocoileus hemionus columbianus) populations in Washington and Oregon (USA). We determined prevalence of HLS in black-tailed deer, September and April fawn:doe ratios, and minimum overwinter survival rates of fawns for selected game management units (GMUs) in western Washington from 1999 to 2001. Prevalence of HLS ranged from 6% to 74% in fawns and 4% to 33% in does. Minimum fawn survival ranged from 0.56 to 0.83 and was unrelated to prevalence of HLS in either does (r=0.005, P = 0.991) or fawns (r=−0.215, P=0.608). The prevalence of HLS in either does or fawns was also unrelated to either fall fawn:doe ratios (HLS does: r= −0.132, P = 0.779; HLS fawns: r=0.130, P = 0.760) or spring fawn:doe ratios (HLS does: r=−0.173, P = 0.711; HLS fawns: r=−0.020, P = 0.963). However, the prevalence of HLS in does and fawns was strongly related (r=0.942, P = 0.002), and GMUs with high prevalence of HLS had lower deer population densities (fawns: r=−0.752, P = 0.031; does: r=−0.813, P = 0.026). Increased overwinter mortality of fawns because of HLS was not supported by our data. Decreased production of fawns, increased summer mortality of fawns, or both were seen in six of eight study GMU–year combinations. Observed rates of productivity and minimum fawn survival were inadequate to maintain population size in five of eight study GMU–year combinations, assuming an annual doe survival rate of 0.75. The influence of deer condition and population health on adult survival, fawn production, preweaning fawn survival, parasitism, and prevalence of HLS in both fawns and adults need to be clarified to identify what factors are limiting black-tailed deer productivity.

Marten (Martes americana) carcasses were collected from trappers in three regions of Alaska. Stomachs were examined for the nematode parasite Soboliphyme baturini. Both prevalence and intensity of infection exhibited an increase from north to south. Prevalence was higher in adults (compared with juveniles) from the two mainland study areas. Prevalences in these two age classes were similar for the southeastern region. There were no sex-specific differences in prevalence. No pathologic changes were observed in the gastrointestinal tract. Impact of the parasite on either individual animals or populations was not detected.

The nonindigenous Barbary sheep population (Ammotragus lervia) of the Sierra Es back. The density of Barbary sheep in the Sierra puña Regional Park (Murcia, Spain) suffered an outbreak of sarcoptic mange between 1991 and 1995, which contributed to a population decrease of 86%. This study presents the results of two population surveys conducted in 1994 and 1999 based on the fixed point and itineraries method (FPI) and the excrement count (EC) method, as well as data from demographic estimates and clinical observations conducted by the Regional Administration of Murcia. Results of surveillance for mange are given between 1992 and 1995, because no animals were observed with sarcoptic mange in 1999. Prevalence of mange peaked in 1994 and then declined. During the regression phase of the epidemic, there was a higher infection rate in males (21.9%) than in females (16.6%) or young animals (5.1%). Males over 5 yr old were the worst affected age group, followed by subadults of both sexes. Few animals had generalized lesions of mange (7%), and most individuals (72%) had lesions of moderate severity. The most common locations of lesions were the neck, head, and back. The density of Barbary sheep in the Sierra Espuña Regional Park increased from introduction in 1972 until it peaked at 13 animals/km in 1991, the year when the first case of sarcoptic mange was detected. After 2 yr of the mange epidemic, the average estimated density was 1.7 animals/km² in 1994, which increased to 5.0 animals/km² in 1999. The average group size also increased from 7.9 to 19.2 animals/group between 1994 and 1999. The sex ratio, expressed as the proportion of females in the total population observed, decreased from 0.61 in 1994 to 0.49 in 1999. The reproduction rate (kids per females per year) was essentially stable (0.59 in 1994 to 0.65 in 1999). Between 1994 and 1999 the population aged, with the number of young animals (<18 mo of age) decreasing from 45.3% to 36.6% from 1994 to 1999. In the same period, the proportion of males increased 21.4% to 32.6%. We believe sarcoptic mange acted as one of the regulating factors of population density after 1991 and that currently, although no sarcoptic mange lesions were observed in the 1999 survey, there is a demographic imbalance in sex ratio, age structure, and density.

Immunoglobulin (Ig) binding patterns of Pacific harbor seals (PHS, Phoca vitulina richardsi) and northern elephant seals (NES, Mirounga angustirostris) to tissues of adult Otostrongylus circumlitus were examined by immunoblotting to investigate the role of age in the unusual response of juvenile NES to infection with O. circumlitus. Serum was taken from NES between March 1997 and March 2001 and from PHS between May 1996 and August 1999. The serum of seals infected with O. circumlitus contained antibodies that bound to all nematode tissues examined. Intensity of band staining on Western blots suggested that there were higher levels of antibody recognizing the excretory-secretory (ES) glands in the serum of NES that were 1 yr and older and in the majority of PHS compared with that in 2- to 9-mo-old NES. All juvenile NES infected with O. circumlitus and a proportion of the PHS and older NES infected with O. circumlitus contained Ig specific to a 28 kDa protein band that was dominant in the female reproductive tract of the nematode. The Ig binding patterns of NES and PHS to adult Parafilaroides sp., larval Pseudoterranova sp., and larval and adult Anisakis sp. differed sufficiently from that of O. circumlitus that immunoblotting for the 28 kDa protein could be useful for diagnosis of this parasite in juvenile NES. The banding patterns suggest that O. circumlitus nematodes die and disintegrate in PHS and NES and that NES of 1 yr and older and most PHS respond differently to the ES glands than 2- to 9-mo-old NES.

Avian vacuolar myelinopathy (AVM) was first recognized as a cause of bald eagle (Haliaeetus leucocephalus) mortality in 1994 in Arkansas (USA) and has since caused over 90 bald eagle and numerous American coot (Fulica americana) mortalities in five southeastern states. The cause of AVM remains undetermined but is suspected to be a biotoxin. Naturally occurring AVM has been limited to wild waterbirds, raptors, and one species of shorebird, and has been reproduced experimentally in red-tailed hawks (Buteo jamaicensis). In this study, chickens and swine were evaluated for susceptibility to vacuolar myelinopathy with the intent of developing animal models for research and to identify specific tissues in affected coots that contain the causative agent. Additionally, submerged, aquatic vegetation, primarily hydrilla (Hydrilla verticillata), and associated material collected from a reservoir during an AVM outbreak was fed to chickens in an effort to reproduce the disease. In two separate experiments, six 4-wk-old leghorn chickens and ten 5-wk-old leghorn chickens were fed coot tissues. In a third experiment, five 3-mo-old domestic swine and one red-tailed hawk, serving as a positive control, were fed coot tissues. In these experiments, treatment animals received tissues (brain, fat, intestinal tract, kidney, liver, and/or muscle) from coots with AVM lesions collected at a lake during an AVM outbreak. Negative control chickens and one pig received tissues from coots without AVM lesions that had been collected at a lake where AVM has never been documented. In a fourth experiment, eight 3-wk-old leghorn chickens were fed aquatic vegetation material. Four chickens received material from the same lake from which coots with AVM lesions were collected for the previous experiments, and four control chickens were fed material from the lake where AVM has never been documented. Blood was collected and physical and neurologic exams were conducted on animals before and once per week during the trials. All animals were sacrificed and necropsies were performed on Day 29 of feeding, with the exception of one treated chicken that was sacrificed and necropsied on Day 15 of feeding. Microscopic lesions of vacuolar myelinopathy were present in the red-tailed hawk and five chickens that received a mixture of all tissues and two chickens that received only gastrointestinal tissues of coots with AVM lesions. Three of four treated chickens in the aquatic vegetation trial developed vacuolar lesions. None of four treatment pigs or any of the negative control animals developed vacuolar lesions. Chickens are susceptible to AVM and may serve as a useful animal model for future studies. Swine may be refractory to AVM or not affected by AVM at the same dose as are chickens and red-tailed hawks. The causative agent of AVM in affected coots is associated with the gastrointestinal tissues. Furthermore, AVM can be reproduced in chickens via ingestion of aquatic vegetation and associated materials collected from a lake during an AVM outbreak. The cause of AVM is most likely present in the materials associated with submerged vegetation because the vegetation itself (hydrilla) was the same at our AVM-positive and AVM-negative sites.

Avian vacuolar myelinopathy (AVM) is a neurologic disease primarily affecting bald eagles (Haliaeetus leucocephalus) and American coots (Fulica americana). The disease was first characterized in bald eagles in Arkansas in 1994 and then in American coots in 1996. To date, AVM has been confirmed in six additional avian species. Attempts to identify the etiology of AVM have been unsuccessful to date. The objective of this study was to evaluate dermal and oral routes of exposure of birds to hydrilla (Hydrilla verticillata) and associated materials to evaluate their ability to induce AVM. Mallards (Anas platyrhynchos) were used in all trials; bobwhite quail (Colinus virginianus) also were used in one fresh hydrilla material exposure trial. Five trials were conducted, including two fresh hydrilla material exposure trials, two cyanobacteria exposure trials, and a frozen hydrilla material exposure trial. The cyanobacteria exposure trials and frozen hydrilla material trial involved gavaging mallards with either Pseudanabaena catenata (live culture), Hapalosiphon fontinalis, or frozen hydrilla material with both cyanobacteria species present. With the exception of one fresh hydrilla exposure trial, results were negative or inconclusive. In the 2002 hydrilla material exposure trial, six of nine treated ducks had histologic lesions of AVM. This established the first cause-effect link between aquatic vegetation and AVM and provided evidence supporting an aquatic source for the causal agent.

Recent studies examined the utility of the chorioallantoic membrane (CAM) as a nonlethal, noninvasive indicator of environmental contaminant exposure in oviparous wildlife. The CAM is a highly vascularized extraembryonic membrane that functions as a site for respiration, nutrient transport, and waste storage during embryonic development. After hatching, the CAM is usually discarded with the eggshell and can be used for chemical residue analysis. Chorioallantoic membranes have been used successfully to examine contaminant exposure and predict chemical concentrations in multiple species of birds and reptiles. In this study, we examined organochlorine (OC) pesticide concentrations in CAMs from eggs of Morelet's crocodiles (Crocodylus moreletii) from northern Belize. Multiple OCs were detected in crocodile CAMs, including aldrin, dieldrin, endrin, dichlorodiphenyltrichloroethane, dichlorodiphenyldichloroethane, dichlorodiphenyldichloroethylene (DDE), heptachlor, lindane, and methoxychlor. Number and concentrations of OC compounds in CAMs were variable. The most prevalent contaminant detected was DDE, which occurred in 69% of CAMs, with concentrations ranging from 0.3 parts per billion (ppb) to 17.0 ppb. The OC burdens in crocodile CAMs confirm contamination of eggs and suggest exposure in embryos and maternal females. These results further support the use of CAMs as qualitative indicators of OC exposure in oviparous wildlife. The efficacy of this sampling technique in the field will depend on the logistics and cost associated with CAM collection and the specific life history traits of the wildlife species.

The purpose of this research was to evaluate persistent organic pollutant (POP) and mercury concentrations in tissues of African fish eagles (Haliaeetus vocifer) and Nile tilapia (Oreochromis niloticus) from Lake Victoria near Entebbe and Lake Mburo, Uganda. Marabou stork (Leptoptilos crumeniferus) nestlings from urban Kampala (40 km from Entebbe) also were sampled for POPs and mercury. Total mercury was measured in the breast feathers of eight nestling and 10 adult African fish eagles from Lake Mburo, 10 nestling and five adult African fish eagles from Lake Victoria near Entebbe, and 20 nestling marabou storks from Kampala from June 2002 through January 2003. Mercury concentrations in all samples were below levels associated with adverse effects in similar species. Mercury concentrations were significantly higher in eagle adults and nestlings from Entebbe than in adults and nestlings from Lake Mburo (P≤0.05). No significant differences (P≥0.05) were found in mercury concentrations between sexes or between the entire fish eagle population sampled at Entebbe and marabou stork nestlings sampled at nearby Kampala. Plasma samples from the same birds were analyzed for 1,1,1-trichloro-2,2-bis(4-chlo-rophenyl)ethane, aldrin, hexachlorocyclohexane (α-HCH), dieldrin, endrin, heptachlor and their metabolites, as well as total polychlorinated biphenyls (PCBs). Nile tilapia whole-body cross sections collected from Lake Mburo (n=3) and Lake Victoria near Entebbe (n=8) also were analyzed for these POPs and mercury. No samples contained POPs or PCBs at the limits of detection except for 4,4′-1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene in five adult eagle plasma samples (0.0026±0.0015 ppm wet weight) and five Nile tilapia samples (0.002±0.001 ppm wet weight) from Entebbe.

Metabolic bone disease has been reported in free-living red squirrels (Sciurus vulgaris) in the United Kingdom but the prevalence of this disease is unknown. In this study the bone quality of free-living red squirrels in the UK was assessed by radiology and bone densitometry. The study comprised 20 red squirrels found dead and submitted to the Zoological Society of London (UK) between 1997 and 1998, 10 were from the Isle of Wight (IoW), where gray squirrels (Sciurus carolinensis) are absent, and 10 were from Cumbria (Cu), where gray squirrels are present. Gray squirrels are considered potential competitors for red squirrels. Radiologic evaluation of humerus, femur, tibia, radius, and ilium revealed a slightly lower bone density and thinner cortices in red squirrels from the IoW when compared with those from Cu. Dual-energy X-ray absorptiometry was used to measure bone mineral content and density of the isolated right humerus and femur of 19 of the 20 red squirrels. The bone densitometry study reinforced the radiographic findings. The IoW specimens had lower bone mineral density values, although statistical significance (P<0.05) between animals from the IoW and Cu was only reached for the proximal epiphysis of the femur and between males from the IoW and males from Cu for the proximal epiphysis of the humerus. A highly positive correlation (r>0.94) was found when the bone mineral content and density between the femur and the humerus among groups and within each group were compared, showing a uniform level of mineralization between upper and lower limbs. These findings suggested generalized bone loss for the IoW red squirrels that may be compatible with some degree of osteopenia. Within the wide range of causes that lead to osteopenia, malnutrition (especially protein deficiency), calcium and copper deficiencies, and genetic factors remain as possible etiologies.

Packed cell volumes (PCVs) and plasma chemistry parameters were measured in 15 adult and 18 nestling African fish eagles (Haliaeetus vocifer) sampled from June 2002 through January 2003 in Uganda. Morphologic measurements were obtained from 15 adult eagles. All eagles were examined for blood parasites and sexed by examination of DNA from red blood cells. Ten adults and eight nestlings were sampled from Lake Mburo and five adults and 10 nestlings were sampled from Lake Victoria near Entebbe, Uganda. Analysis of variance was conducted to assess the association between site, age, sex, and plasma chemistry parameters and the association between sex and morphologic characteristics. Plasma chemistry values for nestling and adult African fish eagles were similar to those reported for other captive and free-ranging eagle species. Packed cell volumes for nestling African fish eagles were markedly lower than values reported for nestlings of other eagle species, although the mean estimated age of nestlings sampled also was lower. A significant association (P≤0.05) was found between PCV of nestling eagles and study site (lower at Lake Mburo) but no association was found between PCV and nestling body weight (P≥0.05). An unidentified Plasmodium sp. was present in erythrocytes of three nestlings from Lake Mburo. No other blood parasites were seen. There was significant variation (P≤0.05) in PCV, calcium, phosphorous, potassium, cholesterol concentrations, and creatine kinase activity between adults and nestlings; all were lower in adults. Aspartate transaminase activity was higher in adults. Like other Haliaeetus sp., body weight, bill depth, culmen length, footpad length, and hallux length as well as bill depth measurements were significantly (P≤0.05) greater for females than males. The objective of the study was to provide baseline biologic and physiologic information that may prove useful in the management and study of captive and wild populations of African fish eagles.

A combination of tiletamine-zolazepam/xylazine (TZ/X) is effective in the chemical immobilization of white-tailed deer (Odocoileus virginianus); however, the lengthy duration of immobilization may limit its usefulness. From October to November 2002, 21 captive female deer were assigned randomly to an α₂ antagonist treatment to reverse xylazine-induced sedation (seven does per group). All deer were given 220 mg of TZ (4.5±0.4 mg/kg) and 110 mg of X (2.2±0.2 mg/kg) intramuscularly (IM). Antagonist treatments were either 200 mg of tolazoline (4.0±0.4 mg/kg), 11 mg of atipamezole (0.23±0.02 mg/kg), or 15 mg of yohimbine (0.30±0.02 mg/kg) injected, half intravenously and half subcutaneously, 45 min after the IM TZ/X injection. In addition, 10 other deer (five per group) were immobilized as before and then given tolazoline (200 mg) after 45 min, with either a carrier (dimethyl sulfoxide [DMSO]) or carrier (DMSO) plus flumazenil (5 mg) to reverse the zolazepam portion of TZ. Mean times from antagonist injection until a deer raised its head were different for α₂ antagonist treatments (P = 0.02). Times were longer for yohimbine (62.3±42.7 min) than for either atipamezole (24.3±17.1 min) or tolazoline (21.3±14.3 min). Mean times from antagonist injection until standing were not different (P=0.15) among yohimbine (112.0±56.4 min), atipamezole (89.7±62.8 min), or tolazoline (52.6±37.2 min). A sedation score based on behavioral criteria was assigned to each deer every 30 min for 5 hr. On the basis of sedation scores, tolazoline resulted in a faster and more complete reversal of immobilization. Flumazenil treatment did not affect recovery.

An outbreak of West Nile virus (WNV) infection occurred at a captive breeding facility for the endangered eastern loggerhead shrike (Lanius ludovicianus migrans) in August 2002. Within 10 d, five birds died; two were found dead, and the others died shortly after showing neurologic signs. West Nile virus was detected in all organs examined using immunohistochemistry, and its viral genome was amplified from brain and kidney samples using reverse transcription–polymerase chain reaction. None of the remaining birds in the colony had antibodies against WNV, which suggests a mortality rate of 100%. After vaccination with a commercial equine WNV vaccine 31 of 37 (84%) of the birds had WNV neutralizing antibodies.

Ectoparasites were collected from chemically immobilized swift foxes (Vulpes velox) in the Texas Panhandle (USA). Three species of fleas (Pulex irritans, Dactylopsylla percernis, and Euhoplopsyllus affinis) and one species of tick (Ixodes sculptus) were found. Pulex irritans was the only abundant ectoparasite; it occurred on all 23 foxes brushed in 1999–2000 and all but one of 34 hosts examined in 2000–01. Otherwise, this swift fox population had a depauperate ectoparasite fauna; the remainder of the ectoparasites only occurred on a few (≤5%) of the hosts. Because of previous taxonomic confusion between P. irritans and the closely related P. simulans, the zoogeographic distribution of these two species in many areas of western North America needs to be verified. Apparently, only the human flea P. irritans occurs on wild canids in the Texas Panhandle. However, there are previous records of P. simulans on other carnivores in western and central Texas. Some of these specimens were reexamined, and their identifications were reconfirmed. Also, the recent literature on the controversial taxonomic status of these two flea species is reviewed. The male terminal aedeagal sexual apparatus is the only means currently available to separate P. irritans and P. simulans.

We studied gastric Helicobacter spp. in five red foxes (Vulpes vulpes). Samples of stomach from the cardia, corpus, pyloric antrum, and duodenum were subjected to histopathologic, immunohistochemical, and transmission electron microscopy (TEM) examination for the presence of Helicobacter and gastritis. All foxes had gastric Helicobacter-like organisms (GHLOs) on examination by light microscopy and TEM. Gastric Helicobacter-like organisms were present in all areas of the stomachs. Chronic mild or moderate gastric inflammation was associated with infection by GHLOs in one or more regions of the stomach, but there was no correlation between inflammation and infection. It is not clear whether the organisms were causing the minimal histologic lesions observed, but the gastric mucosa of free-living foxes appears to be commonly colonized with GHLOs. The frequent colonization of free-living foxes with distinct GHLOs possibly reflects their special characteristic in feeding and/or social behavior or the potential commensal nature of the bacteria in free-ranging foxes.

Birds from the Area de Conservación Guanacaste in northwestern Costa Rica were surveyed for blood parasites in June 2001 and December 2001–January 2002. Of 354 birds examined, representing 141 species of 35 families and 15 orders, 44 (12.4%) were infected with blood parasites. Species of Haemoproteus (4.8% prevalence), Plasmodium (0.6%), Leucocytozoon (0.3%), Trypanosoma (2.0%), and microfilariae (7.6%) were recorded. Twelve species of birds in this survey were examined for blood parasites for the first time. Several new host-parasite associations were identified.

Forty free-ranging elk (Cervus elaphus manitobensis) were captured by net gun in Riding Mountain National Park (Manitoba, Canada) during February 2002 and were administered either saline (control) or xylazine by the intranasal route, to evaluate the efficacy and benefit of intranasal xylazine to reduce stress. Elk that received xylazine had higher relaxation scores than control elk, and the onset of sedation occurred quickly, often <1 min. Serum concentrations of cortisol, creatine kinase, and γ-glutamyltransferase were lower in elk that received xylazine than in control elk. At the conclusion of handling, the intravenous administration of yohimbine quickly abolished the sedative effect of xylazine, which allowed elk to be released without concern of physical injury due to ataxia. The intranasal administration of xylazine can be used to reduce stress in wild animals under situations where they are being handled while physically restrained.

The Salmonella serotypes S. Cerro and S. Newport were isolated from New Zealand sea lions (Phocarctos hookeri) and feral pigs on the Auckland Islands in the New Zealand subantarctic region. The isolates were typed by pulsed-field gel electrophoresis using Xba1 as the restriction enzyme. The isolates were indistinguishable, which suggests that Salmonella infection cycles between sea lions and pigs in this environment. Apart from a previous isolation from a single New Zealand fur seal (Arctocephalus forsteri), S. Newport has not been recorded in any animals from New Zealand, but it is associated with gastroenteritis in humans. Contamination of the marine environment by human waste is a possible source of infection for marine mammals and warrants further investigation.

From 23 to 25 July 2002, 98–103 newly hatched black-bellied whistling ducks (Dendrocygna autumnalis) were observed alive at an inland saline lake (La Sal Vieja) in Willacy County, Texas (USA). Seventy-one (71%) died after showing signs indicative of sodium toxicity within 5 hr of entering the water; some died within minutes. Six carcasses were sent to the United States Geological Survey, National Wildlife Health Center (Madison, Wisconsin, USA) for analysis, and brain sodium levels of all ducklings were above 2,000 parts per million wet weight. More black-bellied whistling duck ducklings are likely to have been affected, but they were not observed after hatching.

We immobilized individuals of four free-ranging felid species, leopard cat (Prionailurus bengalensis), clouded leopard (Neofelis nebulosa), Asiatic golden cat (Catopuma temminckii), and marbled cat (Pardofelis marmorata) with ketamine hydrochloride and xylazine hydrochloride (KH-XH) and with tiletamine hydrochloride and zolazepam hydrochloride (TH-ZH) between March 1998 and July 2002. Mean (±SD) dose of KH and XH was 26.51±5.71 mg/kg and 1.89±0.43 mg/kg, respectively (n=25), and mean dose of TH-ZH was 11.61±3.39 mg/kg (n=28). Dose was significantly correlated with induction time (P<0.001) and duration of anesthesia (P<0.05), but not with recovery time. There were significant differences between the drug combinations in time to induction (P<0.03) and time to anesthesia (P<0.01); recovery times were not significantly different. We conclude that immobilization of these felids with TH-ZH and KH-XH is effective and safe, but TH-ZH is preferred because of the smaller volume of drug necessary for sedation, faster time to induction, and absence of prolonged muscle rigidity during anesthesia.

Within North America, northern (Glaucomys sabrinus) and southern (Glaucomys volans) flying squirrels occupy distinct ranges with limited overlap. Sympatry in northern latitudes coincides with northern hardwood vegetation from Minnesota to New England. Strongyloides robustus is an intestinal parasite that infects both species but appears to be deleterious only to northern flying squirrels. As a result, S. robustus could be a critical determinant of flying squirrel population characteristics in at least some areas of sympatry. However, cold weather could potentially limit the distribution of S. robustus in northern climates. Therefore, we assessed fecal samples from both flying squirrel species to determine the presence of the nematode in Wisconsin. Strongyloides robustus was found in 12 flying squirrel scat samples and infected 52% of southern flying squirrels and 11% of northern flying squirrels. Prevalence of S. robustus infection for northern flying squirrels was substantially lower than previously reported from more southern regions. This is the northernmost documentation of S. robustus in flying squirrels and the first documentation of S. robustus parasitizing flying squirrels in Wisconsin.

Rare species with small population sizes are vulnerable to perturbations such as disease, inbreeding, or random events. The threat arising from microbial pathogens could be large and other species could act as reservoirs for pathogens. We report finding three enteric bacterial species, Salmonella Amager, Campylobacter jejuni, and urease-positive ther-mophilic Campylobacter, in nestling free-flying peregrine falcons (Falco peregrinus) in Sweden in 2000. Campylobacter jejuni isolates exhibited marked genetic similarities to an isolate from a human, providing a possible association between a human-associated strain of this bacterium and peregrine falcons.

Massive urolithiasis of the penile urethra was observed in an adult pygmy sperm whale (Kogia breviceps) stranded on Topsail Island, North Carolina, USA. Calculi occupied the urethra from just distal to the sigmoid flexure to the tip of the penis for a length of 43 cm. A urethral diverticulum was present proximal to the calculi. The major portion of the multinodular urolith weighed 208 g and was 16 cm long × 3.7 cm diameter at the widest point. The urolith was composed of 100% struvite (magnesium ammonium phosphate) and on culture yielded Klebsiella oxytoca, a ureasepositive bacterium occasionally associated with struvite urolith formation in domestic animals. Reaction to the calculi was characterized histologically by moderate multifocal to coalescing plasmacytic balanitis and penile urethritis. Role of the urethrolithiasis in the whale's stranding is speculative but could have involved pain or metabolic perturbations such as uremia or hyperammonemia.

Packed cell volumes (PCV) and plasma chemistry parameters were measured in 20 nestling marabou storks (Leptoptilos crumeniferus) in January 2003 that were a part of a colony located in the center of the city of Kampala, Uganda. There were no significant differences (P≥0.05) in plasma chemistry values or PCV between sexes with the exception of globulin and total plasma protein values, which were higher in females. There were significant differences (P≤0.05) in blood glucose, creatine kinase, and globulin levels between birds of different body weight. Total plasma protein, uric acid, phosphorous, and creatine kinase were generally higher relative to published data on other avian species, including nestling white storks (Ciconia ciconia).

Lead poisoning, associated with ingestion of spent lead shot, was diagnosed in an adult female Pacific loon (Gavia pacifica) observed with partial paralysis on 13 June 2002 and found dead on 16 June 2002 on Kigigak Island, Yukon Delta National Wildlife Refuge, western Alaska, USA. A necropsy revealed three pellets of ingested lead shot in the loon's gizzard and a lead liver concentration of 31 ppm wet weight, which was consistent with metallic lead poisoning. This is the first report of lead poisoning in a Pacific loon and is the only account of lead toxicosis associated with ingestion of lead shot in any loon species breeding in Alaska.

A cardiac rhabdomyoma is described in a 6-wk-old captive fallow deer (Dama dama) that died suddenly without previous clinical signs. The tumor was characterized by multiple nodules composed of large atypical vacuolated myoblastic cells. As previously reported in humans and other animal species, there is compelling evidence that the cardiac rhabdomyoma is a congenital developmental anomaly rather than a true neoplasm. To our knowledge, this is the first report of a cardiac tumor and a rhabdomyoma in a cervid species.

We describe foot infection associated with Arcanobacterium pyogenes in three adult male free-living fallow deer (Dama dama) from Sueve Regional Hunting Reserve (Principality of Asturias, Spain). Affected fallow deer were culled in November 1997 and 1998 during the hunting season. Necropsy, radiography, and microbiologic analysis were carried out for each animal. Unilateral swelling of one extremity at the coronary band was observed in all three cases. Areas of bone loss, severe periosteal reaction, and soft tissue swelling were seen on radiography. Lead fragments were observed in one fallow deer. Seven bacterial species were isolated, but only Arcanobacterium pyogenes was routinely found. Weather conditions in the area (mild temperatures and high humidity), the land (alternating pasture land and rock), the animal population density (both fallow deer and domestic herds of cows, horses, sheep, and goats, live side by side in the same areas), and hunting activities could be related to the frequency of these infections.