Ten juvenile green pythons (Chondropython viridis) died or were euthanized shortly after having been illegally imported into Australia from Indonesia in 1998. Histologic examination of two of the three snakes that died revealed moderately severe chronic ulceration of the nasal mucosa and focal or periacinar degeneration and necrosis of the liver. In addition there was severe necrotizing inflammation of the pharyngeal submucosa accompanied by numerous macrophages, heterophils, and edema. An iridovirus was isolated in culture from several tissues and characterized by immunohistochemistry, electron microscopy, enzyme-linked immunosorbent Assay, polyacrylamide gel electrophoresis, polymerase chain reaction and sequence analysis, restriction endonuclease digestion, and DNA hybridization. This is the first report of a systemic ranavirus infection in any species of snake and is a new member of the genus, Ranavirus.

Enzootic stability, potentially associated with acquired resistance and subsequent transfer of maternal antibodies, innate resistance, or both, has been hypothesized to explain the lack of reports of hemorrhagic disease (HD) in white-tailed deer (Odocoileus virginianus) from Texas. The objectives of this research were to determine the following: how long maternal antibodies to epizootic hemorrhagic disease (EHD) and bluetongue (BT) viruses persist; whether fawns from an enzootic site are naturally exposed to EHD and BT viruses while maternal antibodies are present; and whether field-challenged fawns develop clinical disease. Twelve of 52 fawns from Texas were moved to an indoor facility. All 12 (100%) were positive for maternal antibodies to EHD or BT viruses by agar gel immunodiffusion (AGID) and serum neutralization (SN) tests. Weekly monitoring demonstrated that precipitating antibodies disappeared by 23 wk of age and serum neutralizing antibodies disappeared by 17–18 wk of age. Fawns that remained outdoors in Texas were not observed with signs of HD. At 14–21 wk of age (October), 39 of 40 (98%) fawns that had remained outdoors were positive for EHD and/or BT virus antibodies by AGID and 32 (80%) had SN antibody titers to one or more of five viruses (EHDV-1, EHDV-2, BTV-10, BTV-11, BTV-17). Antibody titers to EHDV-1, EHDV-2, and BTV-11 all exceeded titers of same-age indoor fawns, suggesting recent exposure. Epizootic hemorrhagic disease viruses were isolated from seven (18%) of the outdoor fawns and all 40 remained clinically normal. Natural exposure of deer to EHD and BT viruses occurred at this site in the presence of maternal antibodies without causing disease. This may be due to acquired immunity and the subsequent transfer of maternal antibodies, but it does not exclude innate resistance as a possible factor in the enzootic stability of EHD and BT viruses at this location.

Two young black and white ruffed lemurs (Varecia variegata variegata) died at the San Diego Zoo (San Diego, California, USA) with extensive liver lesions suggestive of acute viral infection. Immunoassays performed to detect hepatitis B virus (HBV) markers were negative. Polymerase chain reaction (PCR) primers overlapping the HBV core gene produced an amplicon of approximately 411 base pairs (bp) from serum DNA of a HBV-positive western lowland gorilla (Gorilla gorilla gorilla) but not from serum DNA of either lemur. Cesium chloride gradient fractions of liver homogenates from both lemurs contained a peak protein fraction with a density of 1.18 g/cm³. Electron microscopic analysis of fraction contents, concentrated by ultracentrifugation, revealed numerous pleomorphic, spherical particles varying in diameter from 16–25 nm. In one of the lemurs, this peak fraction also contained a double-shelled virus-like particle 47–50 nm in diameter. The size, morphology, and density of these particles suggest they are members of the Hepadnaviridae, a group of hepatotropic DNA-genome viruses for which HBV is the prototype.

Tuberculosis due to Mycobacterium bovis infection is endemic in white-tailed deer (Odocoileus virginianus) in the northeastern portion of the lower Michigan peninsula (USA). Various wild carnivores and omnivores, including raccoons (Procyon lotor), are infected with M. bovis within the endemic area. To investigate the pathogenesis of tuberculosis in raccoons and the likelihood of M. bovis transmission from infected raccoons to other susceptible hosts, we experimentally inoculated raccoons with single oral doses of M. bovis (ranging from 30 to 1.7 × 10⁵ colony forming units [CFU]), five daily oral doses of M. bovis (ranging from 10 to 1 × 10⁵ CFU), or a single intravenous (IV) dose of 1 × 10⁵ CFU of M. bovis, from November 1998 through December 2000. Granulomatous lesions consistent with tuberculosis, or tissue colonization with M. bovis, were seen in one of five raccoons in the single low oral dose group, one of five raccoons in the multiple low oral dose group, two of five raccoons in the multiple medium oral dose group, five of five raccoons in the multiple high oral dose group, and five of five raccoons in the IV inoculated group. In orally inoculated raccoons, lesions were most common in the tracheobronchial and mesenteric lymph nodes and lung. Excretion of M. bovis in saliva or nasal secretions was noted in all IV inoculated raccoons and two of five multiple low oral dose raccoons. Mycobacterium bovis was not isolated from urine or feces from any experimentally inoculated raccoons. The need for multiple large oral doses to establish infection, and the low number of orally inoculated raccoons that excreted M. bovis in nasal secretions or saliva, suggest that widespread tuberculosis among raccoons is unlikely.

Eight North American opossums (Didelphis virginiana) were inoculated with 1 × 10⁵ colony forming units of Mycobacterium bovis to investigate their potential as reservoir hosts for bovine tuberculosis in Michigan. Four animals received this dose orally and four were inoculated intramuscularly (IM). In each group, two animals were euthanized 1 mo postinoculation (PI) and two at 2 mo PI. Four control animals were housed separately and sacrificed in the same manner as those inoculated. One of four orally inoculated opossums and three of four IM-inoculated opossums were positive for M. bovis by culture of tissues obtained at necropsy. The oral recipient had positive cultures from intestine and pooled lymphoid samples. Pooled lymphoid samples were positive in three IM-inoculated animals and two of these also had positive liver and lung cultures. One animal with gross and histologic lesions compatible with tuberculosis had negative tissue cultures. The findings suggest that opossums are susceptible to M. bovis infection by multiple routes, although their relative susceptibility compared to true reservoir hosts appears to be low.

Since 1994 an epidemic of mycoplasmal conjunctivitis has spread throughout the eastern house finch (Carpodacus mexicanus) population leading to a significant decline in this population. The infection has not yet been reported from house finch populations west of the Great Plains. We hypothesized that the western population, like the eastern population, is susceptible to infection, and we tested this hypothesis by experimentally infecting house finches from Missoula, Montana (USA) with the house finch strain of Mycoplasma gallisepticum (MG). We compared the response of finches from Montana infected with MG to that of finches from Auburn, Alabama (USA) (October 1999–February 2000). Fifteen house finches from Montana were shipped to Auburn and quarantined for 6 wk at the Auburn University aviary. All birds were negative for MG antibodies when tested by serum plate agglutination assay and MG could not be detected in any bird by polymerase chain reaction. We tested two methods of inoculation, ocular inoculation and contact exposure to an infected finch. Seven house finches from Montana and four house finches from Alabama were infected by bilateral ocular inoculation with 20 μl of a culture containing 1 × 10⁶ color changing units of the house finch strain of MG. The remaining eight house finches from Montana were co-housed with a house finch from Alabama exhibiting mycoplasmal conjunctivitis. After exposure to the pathogen, all house finches became infected, regardless of origin or method of exposure, and all developed conjunctivitis. All birds seroconverted, and evidence of infection could be detected in every bird at some point during the course of disease. Our results suggest that house finches from the western United States are highly susceptible to infection with the house finch strain of MG.

Brucella ovis was isolated for the first time in Italy in 1994 from the genital organs of two domestic rams. In subsequent years bacteriologic and serologic investigations demonstrated an increasing distribution of this disease in domestic sheep. Mouflon (Ovis musimon) occur in several hilly and mountainous areas of Italy where they can potentially contact domestic sheep. To determine if this species may have a role in the epidemiology of B. ovis, four male and four female mouflon, serologically negative for B. ovis and other Brucella spp., were infected intraconjunctivally with B. ovis strain BG1/94. Physical examinations, including collection of blood samples for serology and bacteriology, were performed weekly. The animals were euthanized 8 mo postinoculation (p.i.). Samples of retropharyngeal, parotid, and iliac lymph nodes; bone marrow; kidneys; spleen; epididymis; testicle; bulbourethral glands; seminal vesicles; uterus; and oviducts were collected from each animal as appropriate for histopathology and bacteriology. At the time of euthanasia none of the animals exhibited obvious clinical signs of brucellosis. The animals seroconverted 2 wk p.i. and became seronegative 24 wk p.i. Bacterial cultures, including hemocultures, were negative. No lesions due to B. ovis infection were revealed by histologic examinations. Brucella ovis probably did not infect mouflon and this wild sheep is not likely to play a role in the epidemiology of contagious epididymitis caused by B. ovis.

In January 1998 and 1999, two mass strandings of dolphins occurred in Wellfleet, Massachusetts. The strandings were composed of 97 and 53 animals, respectively. Tissues from 35 Atlantic white-sided dolphins (Lagenorhynchus acutus) from the 1998 stranding and 52 from the 1999 stranding were examined histologically. In the 1998 stranding, unidentified protozoal tissue cysts were seen in skeletal muscle from 11 of 28 (39%) dolphins. In addition, two dolphins had a protozoal tissue cyst in cardiac muscle. In the 1999 stranding, nine of 23 (39%) dolphins had the same protozoal tissue cysts in skeletal muscle. The identification of these protozoal tissue cysts as Sarcocystis sp. was confirmed by light and transmission electron microscopy. The high prevalence of sarcocysts in these dolphins suggests that they are likely intermediate hosts for previously undescribed Sarcocystis spp. The ultrastructure of the sarcocyst walls suggests that more than one species of Sarcocystis are present in dolphins.

The occurrence of infectious keratoconjunctivitis (IKC) was assessed in alpine chamois (Rupicapra rupicapra rupicapra) in Grisons (Switzerland) from 1950 to 1999. The first IKC outbreaks were reported in the 1950's. Since then, the number of affected subpopulations constantly increased and, by 1999, IKC outbreaks were reported in 39 of 51 (77%) chamois sub-populations. From 1992-99, a total of 243 chamois which died of the consequences of IKC were recorded. The number of cases differed between years, and a distinct seasonal trend was observed. Infectious keratoconjunctivitis was more common during summer and autumn, with 48% of the cases recorded in August–October. Juveniles (<4 yr of age) were mostly represented. To verify the presence of Mycoplasma conjunctivae in chamois we analyzed conjunctival swabs taken from animals affected with IKC. Among a sample of 28 affected chamois, M. conjunctivae was identified 14 times (50%). An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect specific M. conjunctivae antibodies in sera of alpine chamois with IKC. We performed a serologic investigation to assess whether M. conjunctivae infection is self-maintained in the chamois population in Grisons. In subpopulations with IKC oubreaks, seroprevalence was low (8%). Seroprevalence was even lower in subpopulations with recent IKC outbreaks (3%). We concluded that the M. conjunctivae infection is not self-maintained in alpine chamois in Grisons. The agent may originate in domestic sheep living in proximity to chamois during summer. Control of IKC in chamois should consider immunoprophylaxis in sheep or limiting interspecific transmission of M. conjunctivae.

Beginning in the fall of 1998 and extending into the spring and early summer of 1999 there was a large epizootic of squirrel fibromatosis in squirrels in seven counties in peninsular Florida. Hundreds of gray squirrels (Sciurus carolinensis) with multiple cutaneous tumors were submitted or reported to biologists, veterinary hospitals, and private wildlife rehabilitators. Most squirrels died or were euthanized soon after submission. Twenty squirrels were submitted for necropsy. The majority of the squirrels examined were adults (12/20) and male (15/20). The number and location of tumors varied widely among the affected squirrels; however, a consistent finding was involvement of the eyelids (20/20). Histopathology revealed a proliferative population of mesenchymal cells within the dermis and marked ballooning degeneration of keratinocytes in the overlying epidermis. Intracytoplasmic viral inclusions were present in the neoplastic mesenchymal cell population and the degenerating keratinocytes. Ulceration and necrosis of the surface of the tumors or associated tissues was present in 14 of the 20 squirrels. Virions consistent with poxvirus were observed via electron microscopy in samples collected from a representative tumor. Death of the squirrels was attributed to emaciation, tissue damage, and severe negative energy balance associated with poxvirus infection and massive tumor growth. The underlying cause of this unusual epizootic of fibromatosis in gray squirrels remains unknown.

Intra- and interspecific contact rates of 12 adult (five females, seven males) raccoons (Procyon lotor) were recorded while these animals fed at a rural garbage dump 40 km north of Kingston, Ontario, Canada from 15 June to 5 September 1995. While raccoons were being observed, they bit, and were bitten, by their conspecifics an average of 0.99 (±0.21) and 1.28 (±0.21) times per hour, respectively, while feeding. Based on mean nightly contact rates (which included time when raccoons were not observed), raccoons bit one of their conspecifics once every 3 nights while feeding. The mean rate of bites made and received per hour for males was not significantly different from lactating females. There was no detectable difference between the mean rate of bites made and received per hour for raccoons which regularly versus occasionally fed at the dump. No interspecific contacts were observed, though raccoons and striped skunks (Mephitis mephitis) often fed at the dump concurrently. The contact rates in this study are the first to be calculated for raccoons directly from field data and will be useful as a point of reference for modeling rabies spread in raccoons in areas with similar site characteristics.

From December, 1997, through November, 2000, 306 deaths were documented among adult and subadult American alligators (Alligator mississippiensis) of Lake Griffin, Florida (USA). Some live alligators were lethargic and unresponsive to approach. To determine the cause, we examined ten alligators captured from Lake Griffin between December 1997 and June 1999. Initially, four alligators, three of which were clinically unresponsive, were sacrificed for routine diagnostic necropsy. The other six Lake Griffin alligators, and five control alligators captured from Lake Woodruff National Wildlife Refuge, Florida, where mortality was negligible, were studied extensively by clinical neurologic examination, electromyography, hematology, serum chemical analyses, and blood culture, then sacrificed and necropsied. Samples of brain, spinal cord, peripheral nerves, skeletal muscle, and major internal organs were examined by light microscopy for abnormalities. Samples of nervous tissue also were examined by electron microscopy, and samples of various tissues were collected for toxicologic analyses. Clinical signs included swimming in circles, inability to submerge, lethargy, weakness, unresponsiveness, slow reflexes, dragging the dorsal surfaces of the hind feet, head tilt, and anisocoria. Lake Griffin alligators had significantly lower distal sciatic nerve conduction velocities than Lake Woodruff alligators, and the most severely affected alligators had the lowest velocities; but morphologic abnormalities in peripheral nerves were not evident in most cases. Three severely affected alligators had acute focal necrosis of the torus semicircularis in the midbrain, two had skeletal myofiber atrophy, another had diffuse nonsuppurative encephalomyelitis, and one mildly affected alligator had skeletal myodegeneration. The cause or causes have not yet been identified.

White-tailed deer (Odocoileus virginianus) are reservoirs for Mycobacterium bovis in northeast Michigan, USA. Production of nitric oxide (NO) by activated macrophages is a potent mechanism of mycobacterial killing. The capacity of macrophages to produce NO, however, varies among mammalian species. The objective of this study was to determine if mononuclear cells from white-tailed deer produce nitrite as an indication of NO production and, if so, is NO produced in response to stimulation with M. bovis antigens. Supernatants were harvested from adherent peripheral blood mononuclear cell (PBMC) cultures that had been stimulated with either Mannheimia haemolytica lipopolysaccharide (LPS) or media alone (i.e., no stimulation). Nitrite levels within M. haemolytica LPS-stimulated culture supernatants exceeded (P < 0.05) those detected within supernatants from non-stimulated cultures as well as those detected within supernatants from cultures receiving an inhibitor of NO synthase in addition to M. haemolytica LPS. In response to stimulation with M. bovis antigens, nitrite production by PBMC from M. bovis-infected deer exceeded (P < 0.05) the production by PBMC from non-infected deer. The response of PBMC from infected deer to M. bovis antigens exceeded (P < 0.05) the response of parallel cultures from the same deer receiving no stimulation. The response of PBMC from M. bovis-infected deer to M. avium antigens did not differ from that of PBMC from M. bovis-infected deer to no stimulation or from that of PBMC from non-infected deer to M. avium antigens. These findings indicate that adherent PBMC from white-tailed deer are capable of NO production and that mononuclear cells isolated from M. bovis-infected white-tailed deer produce NO in an antigen-specific recall response.

Elk (Cervus elaphus) are reservoirs for Brucella abortus, Mycobacterium bovis, and Mycobacterium avium subsp. paratuberculosis, each a serious pathogen of domestic livestock. An understanding of the basic immune responsiveness of elk would aid efforts to develop methods to diagnose and prevent these diseases of elk. Peripheral blood mononuclear cells (PBMC) isolated from captive elk were examined for phenotype, lymphocyte subset proliferative capacity, and ability to produce nitric oxide (NO) upon pokeweed mitogen (PWM) stimulation. Although γδ TCR cells represented a high percentage of the peripheral blood lymphocyte pool, these cells responded poorly to PWM stimulation. B cells (i.e., sIgM cells), conversely, were responsive to PWM stimulation. Addition of PWM to PBMC cultures also resulted in a significant production of nitrite, the stable oxidation product of NO. Similar to other ruminant species, the majority of elk peripheral blood sIgM cells co-expressed MHC class II and B-B4, a B cell lineage marker that varies in expression during B cell development. Findings from the present study provide basic information on several parameters of cellular immunity of elk.

The objective of the study was to develop a bait and baiting system capable of delivering one effective dose of oral rabies vaccine to each member of a free-ranging African wild dog (Lycaon pictus) pack. Trials were conducted between June and October 2000. The results of cafeteria-style bait preference trials testing seven candidate baits in captive wild dogs revealed a significant preference for chicken heads (June trials: P = 0.023, September trials: P = 0.021). Trials using a topical biomarker (rhodamine B) showed that chicken head baits were sufficiently chewed on most occasions to rupture the vaccine container. Free-ranging wild dogs and young pups ingested chicken head baits. Significant dominance of bait intake by a single individual was seen in four of six study packs and in the three packs in which an alpha pair could be distinguished, the dominant feeder was an alpha animal. Pattern of bait distribution and degree of satiation had no effect on pack coverage (proportion of pack ingesting at least one bait). Pack coverage was significantly related to trial number (r = 0.71, P < 0.001), with pack coverage increasing with increased exposure of the pack to the baits. During 46 hr of diurnal observations of free-ranging wild dogs only two baits were lost to non-target species. A baiting system for the oral vaccination of captive and free-ranging wild dogs is proposed.

Research was conducted during 1996–2000 to develop baits for delivering an oral rabies vaccine to raccoons (Procyon lotor) and coyotes (Canis latrans). A bait was sought that: (1) was attractive to the target species, (2) could be distributed by aircraft, (3) was as effective (or more so) than the currently used fish meal polymer bait, and (4) could be produced in large numbers by automated procedures and could be purchased by user groups at substantially lower cost.

Ten field trials were conducted to document raccoons' bait flavor preferences, evaluate a new vaccine sachet bait coated with various attractants, and determine if the sachet bait would effectively deliver Raboral V-RG® oral rabies vaccine (Merial Limited, Athens, Georgia, USA) to this species. Raccoons preferred fish and crustacean-based flavors over those derived from plant materials. Raccoon visits to tracking stations, frequency of bait removals, and percent of sachets discarded by this species that were emptied of placebo vaccine indicated efficacy of the new bait was equal or superior to the currently used fish meal polymer bait. A field trial conducted in fall 1998 compared aerially distributed vaccine-laden sachet and polymer baits and showed there was no difference between the percent of raccoons from the test and reference areas subsequently found positive for rabies antibody.

Four bait trials to determine coyote response to sachet baits were conducted in 1997–98. The propensity for canids to gulp or bolt smaller food items is well known. Thus, a first trial involved offering fish-flavored sachet baits of different sizes to 30 captive coyotes to determine if smaller size baits were more frequently swallowed intact. Two field trials were also conducted in fall 1997 to determine if free-ranging coyotes discriminated among sachet baits coated with different attractants. Finally, Raboral V-RG®-laden poultry-flavored sachet baits were aerially dropped and the percent of seropositive coyotes was compared with coyotes from surrounding areas where fish meal polymer vaccine baits had been distributed.

Captive coyotes did not swallow sachet baits intact, regardless of size. Bait preference field trials indicated that coyotes preferred poultry, cheese/beef tallow, and fish-flavored sachet baits and that such baits were taken at the same rate as polymer baits. A sample of coyotes from the area baited with vaccine-laden sachet baits had a markedly higher (P = 0.01) seropositivity rate than coyotes from areas where vaccine was distributed in polymer baits.

Sachet bait production could be facilitated by automated technology and sachet baits used either as an alternative vaccine delivery device or in combination with the fish meal polymer bait.

A field study was carried out on Little Island (County Waterford, Ireland) in June 2000 to evaluate the potential of a bait-marking system for use in European badgers (Meles meles). Two oral biomarkers, sulfadimethoxine (SDM) and rhodamine B, were incorporated into fishmeal baits and distributed by hand at main setts in five test territories for 3 consecutive days. In parallel, non-biomarked baits were distributed at a single control territory. The objectives of the study were to: (1) assess the effects of SDM and rhodamine B on palatability and thus bait acceptance, and (2) investigate the marking capacity of SDM and rhodamine B in serum and hair samples taken from badgers. Trapping was carried out in each territory for 5 consecutive days immediately after bait distribution. Analysis of data revealed that 90–100% of baits were removed in four of the test territories and from the control territory. In the fifth test territory, 61% of baits were removed. Of the badgers (n = 26) trapped in the test territories, 18 (69%) were positive when tested for both biomarkers. In contrast, the remaining eight animals and those captured in the control territory (n = 6 badgers) were negative. In the marked animals, the highest levels of SDM were recorded in serum samples taken soon after bait distribution. Thereafter, the levels declined in each badger over the course of the study. In contrast, rhodamine B was readily detectable by fluorescence microscopy of hair samples throughout the period of study. The results indicate that SDM and rhodamine B act as systemic markers in badgers and have potential future applications for monitoring of oral vaccine uptake.

In the summers of 1996 and 1997, 60 wild pigs (Sus scrofa) were necropsied from three sites in south Texas (USA) to test the hypothesis that serum and whole blood parameters vary significantly (P ≤ 0.05) with the prevalence and intensity of parasites infecting wild pigs. We found ten parasite species: five nematodes (Metastrongylus salmi, Metastrongylus pudentotectus, Stephanurus dentatus, Oesophagostomum dentatum, and Physocephalus sexalatus); four ixodid ticks (Amblyomma cajennense, Amblyomma maculatum, Amblyomma americanum, and Dermacentor variabilis); and one trematode (Fascioloides magna). Among juvenile pigs, the intensity of the four species of ticks, collectively, was negatively correlated (P ≤ 0.05) with whole blood principal component number one (PC-1); this factor was positively associated with lymphocytes and eosinophils. Lungworm intensity (Metastrongylus spp.) among adult pigs was negatively correlated (P ≤ 0.05) with whole blood PC-2; this factor was negatively associated with segmented neutrophils and monocytes. There were no significant correlations found between parasite prevalences and either serum or whole blood principal component factors. The correlations observed between parasite intensities and serum and whole blood parameters generally were weak. Thus, we found no strong evidence that serum and whole blood parameters provided good predictive information on parasite infections in wild pigs for most practical management decisions.

Prevalence of egg-laying disorders and hematology and blood chemical parameters were analyzed in free-ranging common chameleons (Chamaeleo chamaeleon) from southern Spain. During four reproductive seasons oviposition failures occurred only during dry years. Egg binding appeared to be an important cause of mortality. Oviductal eggs of dystocic females were longer and wider than those of females with normal oviposition. Blood cell counts, white blood cell differentials, hematocrit, and concentration of hemoglobin, total plasma protein, glucose, uric acid, aspartate aminotransferase, and creatinine phosphokinase in blood were determined for eight apparently healthy post-reproductive females and considered as reference values. These chameleons differed from other reptiles in high concentrations of glucose in blood, averaging 362 mg/dl, and in high numbers of heterophils. Females with dystocia differed from reference values in an increase in monocytes and in the high concentrations of aspartate aminotransferase probably associated with tissue trauma.

Several disease syndromes in captive rhinoceroses have been linked to low vitamin status. Blood samples from captive and free-ranging black (Diceros bicornis) and white rhinoceros (Ceratotherium simum) and tissue samples of captive individuals from four rhinoceros species were analysed for vitamins A and E. Circulating vitamin A levels measured as retinol for free-ranging versus captive black and white rhinoceros were 0.04 (±0.03 SD) vs. 0.08 (±0.08) and 0.07 (±0.04) vs. 0.06 (±0.02) μg/ml, respectively. Circulating vitamin E levels measured as α-tocopherol were 0.58 (±0.30) vs. 0.84 (±0.96) and 0.62 (±0.48) vs. 0.77 (±0.32) μg/ml, respectively. In contrast to earlier findings, there was no significant difference in vitamin E concentration between captive and free-ranging black rhinoceros. When the samples of captive black rhinoceros were grouped into those taken before 1990 and after 1990, however, those collected before 1990 had significantly lower (P < 0.001) vitamin E levels (0.46 ± 0.83 μg/ml) and those collected in 1990 or later significantly higher (P < 0.001) vitamin E levels (1.03 ± 1.04 μg/ml) than the captive population as a whole. This is probably due to increased dietary supplementation. There were significant differences in circulating vitamin concentrations in black rhinoceroses from different regions in the wild. Serum 25-hydroxy (OH) vitamin D₃ averaged 55.7 ng/ml in free-ranging rhinoceroses; no carotenoids were detected in any blood samples. Captive black and white rhinoceroses appear to be adequately supplemented in vitamin A and E. Captive Indian rhinoceroses (Rhinoceros unicornis) had significantly lower vitamin A concentrations in blood (P < 0.001) and higher vitamin A concentrations in liver tissue samples (P < 0.001) than other rhinoceros species. Equine requirements are not recommended as a model for rhinoceros vitamin requirements.

Vitamin E (measured as α-tocopherol) and cholesterol concentrations were determined in plasma samples collected from 86 clinically healthy captive adult bustards of six species and 23 captive juveniles (6–12 mo old) of two of these species. Adult houbara bustards (Chlamydotis undulata macqueenii) had higher plasma α-tocopherol concentrations than juveniles (adult: mean ± SE, 11.07 ± 0.41 μg/ml, n = 32; juvenile: 6.33 ± 0.48, n = 12) and higher α-tocopherol : cholesterol ratios (adult: 6.09 ± 0.44, n = 12; juvenile: 2.94 ± 0.22, n = 11). No age difference was evident for kori bustard (Ardeotis kori) plasma α-tocopherol concentrations (adult: 4.43 ± 0.42, n = 21; juvenile: 4.46 ± 0.26, n = 11) or α-tocopherol : cholesterol ratios (adult: 3.67 ± 0.44, n = 20; juvenile: 3.71 ± 0.36, n = 11). Adult houbara bustards had significantly higher (P < 0.01) α-tocopherol concentrations compared with adult rufouscrested (Eupodotis ruficrista; 6.64 ± 0.33, n = 19) and white-bellied (Eupodotis senegalensis; 7.75 ± 0.81, n = 8) bustards, but similar α-tocopherol : cholesterol ratios (rufouscrested: 5.56 ± 0.32, n = 18; white-bellied: 5.83 ± 0.43, n = 8). Juvenile houbara bustards had higher plasma α-tocopherol concentrations than juvenile kori bustards but similar α-tocopherol : cholesterol ratios. Adult houbara bustard plasma α-tocopherol levels and α-tocopherol : cholesterol ratios did not differ significantly between sexes. The vitamin E status of adult bustards appeared to be influenced by environmental conditions that varied due to species-specific husbandry regimes, but no clear relationship was seen with dietary vitamin E levels. Juvenile bustards did not have higher vitamin E levels than adults, despite being maintained on four-fold dietary vitamin E concentrations and in similar environmental conditions. This paper presents the first published data for plasma vitamin E concentrations in bustards. The plasma α-tocopherol and cholesterol concentrations and α-tocopherol : cholesterol ratios of captive bustards were similar to those previously reported for omnivorous avian species. Further research is required to determine which components of the identified environmental conditions affect bustard vitamin E status and to confirm whether differences exist between species independent of the variation in their management regimes.

Raccoons and skunks are major rabies reservoirs in North America. Oral vaccination is one method to consider for disease control in these carnivores. Under field conditions in the USA, only one oral rabies vaccine has been used. It is efficacious in wildlife such as raccoons (Procyon lotor), coyotes (Canis latrans), and foxes (Vulpes vulpes) but not in skunks (Mephitis mephitis). The objectives of this study were to evaluate an attenuated SAG-2 rabies virus vaccine for safety, immunogenicity, and efficacy by the oral route in skunks and raccoons. Two of five skunks and three of five raccoons developed virus neutralizing antibodies (VNA) by day 14 following oral administration of SAG-2 vaccine. All animals remained healthy. Upon challenge, naive controls succumbed to rabies. Among vaccinated animals, four of five skunks and all five raccoons had VNA on day 7 post-challenge and all survived. Given these results, SAG-2 is a promising candidate vaccine that may satisfy both safety and efficacy concerns for oral rabies immunization of major North American rabies reservoirs.

Safety of the modified live rabies virus vaccine, SAD B19, was studied in striped skunks (Mephitis mephitis). Seven skunks received 10^7.9 foci formatting units by direct oral administration. In four cages, a vaccinated animal was placed with a control animal, the other three vaccinated skunks were housed individually. Saliva and nasal swabs were collected 1, 2, 4, 24, 48, and 72 hr post-vaccination. From all vaccinated and control animals (n = 11) blood samples were collected 0, 28, 56, 84, and 296 days post-vaccination. Three of seven vaccinated skunks seroconverted. None of the control animals had detectable levels of rabies virus neutralizing antibodies. Also no vaccine virus was isolated from the nasal and saliva swabs collected from any animal. Thus, SAD B19 was innocuous for skunks in our study after direct oral administration at field concentration.

Sarcocystis sp. schizonts were found in the cerebellum of a northern gannet (Morus bassanus), exhibiting neurologic signs, found on the Florida (USA) east coast. Based upon molecular characterization of DNA isolated from the brain of the gannet, this Sarcocystis sp. appeared to be closely related, if not identical, to an unnamed Sarcocystis sp. typified by isolates 1085 and 1086 collected from feces of a Virginia opossum (Didelphis virginiana) on the east coast of Florida. Because the life cycle of this parasite appears to be land based, urban waste discharge to marine/estuarine environments may be a source of infection for marine species.

A large commercial flock of Hungarian partridge (Perdix perdix) experienced elevated mortality associated with a wasting disease in May 1998. Postmortem examination of females consistently revealed a distended crop and abnormal gray-white tissue infiltrating the wall of the crop and thoracic esophagus. Neoplasia in male partridge was observed in the liver. Microscopic examination of the crop and thoracic esophagus revealed transmural masses of immature lymphocytes with frequent mitotic figures. Similar cells were observed in the liver of affected males. Virus particles consistent in size and morphology with reticuloendotheliosis virions were observed in neoplastic lymphoid cells via electron microscopy. Reticuloendotheliosis virus was isolated from each of four blood samples. This disease has not previously been reported in Hungarian partridges. Hungarian partridge may represent a potential reservoir of infection for other gamebirds, including prairie chickens.

Sixteen brown skuas (Catharacta antarctica lonnbergi) and seven South Polar skuas (C. maccormicki) were found dead near Boekella Lake, Hope Bay, Antarctica, in February 1997. Postmortem examination revealed conspicuous caseous, deep yellow fungal/mycelial mats or cores in the trachea of nine of 19 carcasses that were examined. These mycelial cores, highly suggestive of aspergillomas, completely occluded the tracheal lumen in four of these nine carcasses. Thelebolus microsporus, a psychrophilic ascomycetous fungus commonly isolated from skua dung and skua nesting material, was isolated in pure culture from these tracheal plugs. Awareness of pseudolesions resulting from Thelebolus microsporus profuse postmortem growth in the trachea of dead skuas will minimize potential confusion with aspergillosis when investigating causes of epornithics in Antarctica.

A natural infection of the meningeal worm, Parelaphostrongylus tenuis, persisted for at least 3.7 yr in a white-tailed deer (Odocoileus virginianus). The deer was 5–7 yr old and was shedding dorsal-spined nematode larvae at the time of quarantine. Larvae were extracted from all fecal samples collected up to 730 days post-quarantine (dpq) and thereafter only at 862 dpq and at necropsy (1,350 dpq). Live adults of P. tenuis, one male and one female, were recovered from the cranium at necropsy. Parelaphostrongylus tenuis infections are long lived and latent periods may be extended. Our findings reaffirm the need for reliable antemortem diagnosis to identify non-patent P. tenuis infections to prevent inadvertent introduction of infected animals to non-endemic areas.

The nematode, Abbreviata terrapenis (Physalopteridae) was found in 16 (6%) of 267 banded rock rattlesnakes (Crotalus lepidus klauberi) from Arizona and New Mexico. Abbreviata terrapenis in C. lepidus represents an accidental parasite in that “infection” was acquired by the ingestion of lizard prey. Feeding captive snakes on wild-caught lizards poses a risk of introducing nematodes to the snakes.

A dose range was determined for anesthesia of recently bomacaptured Lichtenstein's hartebeest (Sigmoceros lichtensteinii) (n = 13) with the synthetic opiate thiafentanil (THIA) (formerly called A3080) combined with medetomidine (MED) and ketamine (KET) in the Kasungu National Park, Malawi on 4 to 5 September 1999. The dose range of 11–26 μg/ kg THIA (mean ± SD = 21 ± 4 μg/kg) combined with 5–10 mg/kg MED (8 ± 1 μg/kg) plus 0.7–1.4 mg/kg KET (1.1 ± 0.2 mg/kg) was found to be safe and effective for the field conditions associated with this study. The anesthesia produced by this drug combination was very predictable and characterized by a short induction time (3:34 ± 1:20 min : sec), good muscle relaxation, and acceptable physiologic parameters for anesthesia periods ranging from 22:30–35:00 min : sec (31:14 ± 2:50). Within the range of doses used in this study, times to onset of initial effects and recumbency were not dependent on THAI, MED, or KET doses. Anesthesia was rapidly and completely reversed by intravenous injections of naltrexone at 30 times the THAI dosage (0.69 ± 0.19 mg/kg) and atipamezole at about four times the MED dosage (38 ± 14 μg/kg). There was no residual effect from ketamine noted following reversal of THIA and MED and no mortality or morbidity was associated with this anesthetic regimen.

Members of the genus Basidiobolus, a saprophytic fungus, have been associated with the digestive tracts of a wide variety of amphibians and reptiles. To elucidate the relationship of Basidiobolus sp. with amphibians in central Florida (USA), we document the occurrence of the fungus in the digestive tracts of Bufo terrestris, Buffo quercicus, Hyla femoralis, Hyla cinerea, Hyla gratiosa, Hyla squirella, Osteopilus septentrionalis, and Rana utricularia. Species that occupy terrestrial habitats (B. terrestris, B. quercicus, and R. utricularis) were found to harbor Basidiobolus spp. more frequently (83, 78, and 91%, respectively) than those that occupied a more arboreal habitat (H. cinerea, H. squirella, H. femoralis, H. gratiosa, and O. septentrionalis (50, 56, 55, 56, and 70%, respectively).

This study evaluated partial antagonism of tiletamine-zolazepam (TZ) anesthesia in cheetahs (Acinonyx jubatus) and differences between two benzodiazepine antagonists, flumazenil and sarmazenil, in this species. Four cheetahs were anesthetized three times at an interval of 14 days with an average intramuscular dose of 4.2 mg/kg TZ. In trials 2 and 3 flumazenil at 0.031 mg/kg and sarmazenil at 0.1 mg/kg, respectively, were applied intramuscularly 30 min after initial TZ injection. There was a highly significant difference between the duration of TZ anesthesia with and without antagonist. Use of the antagonists significantly shortened duration and recovery and eliminated excitatory behavior during the recovery phase. No significant differences could be determined between the two antagonists. We recommend the use of sarmazenil and flumazenil to antagonize TZ anesthesia in cheetahs.

This is the first report of an epicaridean isopod infecting cephalopods. Three cryptoniscus larvae (Isopoda, Epicaridea) were recognized externally and found entirely embedded in the oral bulb at the beginning of the esophagus of two female Patagonian squid (Loligo gahi) sampled in North Peruvian and South Chilean waters, respectively. There was an extremely low prevalence (<2%) and mean intensity (one) of infection which we believe indicated an accidental infection. However, the tissue location indicated successful penetration and colonization of the squid host.

Previous work demonstrated that Ixodes spinipalpis ticks maintained an enzootic cycle of Borrelia bissettii and the agent of human granulocytic ehrlichiosis (aoHGE) within woodrats (Neotoma mexicana) and deer mice (Peromyscus maniculatus) in northern Colorado (USA). Because I. spinipalpis is the only known vector of B. bissettii and aoHGE in Colorado, this study was designed to determine the reservoir status of other hosts of I. spinipalpis in five distinct ecological zones along the front range and foothills of Colorado. One hundred and twelve rodents of nine species were examined and 11 (10%) were polymerase chain reaction (PCR) positive for aoHGE; 37 (33%) were culture positive for B. bissettii, and five (4%) were coinfected with both organisms based on PCR and culture. Of these, three chipmunk species (Tamias minimus, T. quadrivittatus, and T. umbrinus) were culture positive for B. bissettii, with a single T. minimus coinfected with B. bissettii and aoHGE. In addition, one golden-mantled ground squirrel (Spermophilus lateralis) was positive for both B. bissettii and aoHGE. This is the first report of a golden-mantled ground squirrel harboring either B. bissettii or aoHGE and the initial observation that chipmunks may be a reservoir for B. bissettii in Colorado.