Between March 1981 and June 1995, a neurological disease characterized histologically by spongiform encephalopathy was diagnosed in 49 free-ranging cervids from northcentral Colorado (USA). Mule deer (Odocoileus hemionus) were the primary species affected and accounted for 41 (84%) of the 49 cases, but six Rocky Mountain elk (Cervus elaphus nelsoni) and two white-tailed deer (Odocoileus virginianus) were also affected. Clinical signs included emaciation, excessive salivation, behavioral changes, ataxia, and weakness. Emaciation with total loss of subcutaneous and abdominal adipose tissue and serous atrophy of remaining fat depots were the only consistent gross findings. Spongiform encephalopathy characterized by microcavitation of gray matter, intraneuronal vacuolation and neuronal degeneration was observed microscopically in all cases. Scrapie-associated prion protein or an antigenically indistinguishable protein was demonstrated in brains from 26 affected animals, 10 using an immunohistochemical staining procedure, nine using electron microscopy, and seven using Western blot. Clinical signs, gross and microscopic lesions and ancillary test findings in affected deer and elk were indistinguishable from those reported in chronic wasting disease of captive cervids. Prevalence estimates, transmissibility, host range, distribution, origins, and management implications of spongiform encephalopathy in free-ranging deer and elk remain undetermined.

Using a virus neutralization technique, we found phocine distemper virus (PDV) antibody in 130 (83% of 157) harp seals (Phoca groenlandica) from the western North Atlantic sampled between 1988 and 1993 inclusive. In contrast, only 44 (24% of 185) hooded seals (Cystophora cristata) had antibodies against PDV even though they were sympatric with harp seals and were sampled over a similar period, from 1989 to 1994 inclusive. Antibodies occurred in 106 (41%) of 259 ringed seals (Phoca hispida); this prevalence was higher than expected given the solitary behavior and territoriality characteristic of this species. Seropositive ringed seals were found at each of seven locations across Arctic Canada from Baffin Bay to Amundsen Gulf at which samples were collected between 1992 and 1994. However, the prevalence of infection was highest where ringed seals are sympatric with harp seals in the eastern Canadian Arctic.

Between 1985 and 1994, 368 cases of rabies in rodents (95% of reports) and lagomorphs (5%) were reported to the Centers for Disease Control and Prevention, Atlanta, Georgia (USA), from 22 states. This was a 354% increase from the period 1971 to 1984. Most reports were cases of rabies in woodchucks (Marmota monax) (n = 317), primarily from the eastern United States, which has been recently experiencing an epizootic of raccoon (Procyon lotor) rabies. Cases of rabies in woodchucks were temporally and spatially associated with reports of raccoon rabies. Antigenic or genetic characterization of variants of rabies viruses from rodents and woodchucks corresponded to the variants associated with the major terrestrial wildlife reservoir within the geographic region of specimen origin. Although rodents and lagomorphs are infrequently infected with rabies and human contact with these animals rarely requires postexposure treatment, appropriate health authorities need to evaluate individual circumstances surrounding potential exposures.

Raccoons (Procyon lotor) were live-trapped and examined for ticks from July 1990 to July 1993 in the coastal plain of North Carolina on Marine Corps Base, Camp Lejeune, North Carolina (USA). Five species of ixodid ticks were found on 351 (78%) of 449 raccoons. Amblyomma americanum was the most abundant tick found on raccoons. Dermacentor variabilis, Ixodes texanus, and Ixodes scapularis were frequently collected, while Ixodes cookei were rarely collected from raccoons. Tick burdens were not affected by the age, sex, or trap location of captured raccoons. Ticks parasitizing raccoons had varying seasonal patterns of abundance. Amblyomma americanum were generally collected from raccoons year around, but infestation intensities were greatest in summer from June to September. Dermacentor variabilis adults were most abundant in mid-summer while peak numbers of larvae were collected in the fall. Infestation intensities of Ixodes texanus larvae were greatest in fall and winter months while nymphs were most abundant in winter and spring. No males were collected from raccoons, but females were most frequently collected in the spring and declined in abundance in the summer with no specimens collected in the fall or winter. Numbers of I. scapularis adults appeared to reach peak numbers in the fall while larvae and nymphs were most abundant on raccoons in winter. Spirochetes, Borrelia burgdorferi, were identified in a small percentage (0.2%) of host-seeking A. americanum nymphs and adults, and I. scapularis adults by immunofluorescent antibody assays. Similarly, a small percentage (1.9%) of host-associated A. americanum, D. variabilis, I. texanus and I. cookei contained B. burgdorferi. Borrelia burgdorferi spirochetes were cultured from the blood of 23 (26%) of 87 raccoons.

The role of the eastern chipmunk (Tamias striatus) in the epizootiology of Lyme borreliosis was evaluated in Castle Rock State Park, Illinois (USA), an enzootic region, from June to August 1993. Prevalence, intensity, and molting rate of immature Ixodes scapularis were determined for chipmunks, white footed mice (Peromyscus leucopus), and raccoons (Procyon lotor). Chipmunks were the primary host for I. scapularis nymphs and an important secondary host for I. scapularis larvae. Based upon ear punch biopsy analysis, B. burgdorferi prevalence in chipmunks was similar to that of mice in August and greater than that of mice in June and July. Thus we propose that chipmunks are the primary source of B. burgdorferi infection for I. scapularis nymphs and an important secondary source of infection for larvae.

From October 1989 to June 1993, we captured and sampled 110 coyotes (Canis latrans) for various diseases in Yellowstone National Park, Wyoming (USA). Prevalence of antibodies against canine parvovirus (CPV) was 100% for adults (>24 months old), 100% for yearlings (12 to 24 months old), and 100% for old pups (4 to 12 months old); 0% of the young pups (<3 months old) had antibodies against CPV Presence of antibodies against canine distemper virus (CDV) was associated with the age of the coyote, with 88%, 54%, 23%, and 0% prevalence among adults, yearlings, old pups, and young pups, respectively. Prevalence of CDV antibodies declined over time from 100% in 1989 to 33% in 1992. The prevalence of canine infectious hepatitis (ICH) virus antibodies was 97%, 82%, 54%, and 33%, for adults, yearlings, old pups, and young pups, respectively. The percentage of coyotes with ICH virus antibodies also declined overtime from a high of 100% in 1989 to 31% in 1992, and 42% in 1993. Prevalence of antibodies against Yersinia pestis was 86%, 33%, 80%, and 7%, for adults, yearlings, old pups, and young pups, respectively, and changed over time from 57% in 1991 to 0% in 1993. The prevalence of antibodies against Francisella tularensis was 21%, 17%, 10%, and 20%, for adults, yearlings, old pups, and young pups, respectively. No coyotes had serologic evidence of exposure to brucellosis, either Brucella abortus or Brucella canis. No coyotes were seropositive to Leptospira interrogans (serovars canicola, hardjo, and icterohemorrhagiae). Prevalence of antibodies against L. interrogans serovar pomona was 7%, 0%, 0%, and 9%, for adults, yearlings, old pups, and young pups, respectively. Antibodies against L. interrogans serovar grippotyphosa were present in 17% of adults and 0% of yearlings, old pups, and young pups. Many infectious canine pathogens (CPV, CDV, ICH virus) are prevalent in coyotes in Yellowstone National Park, with CPV influencing coyote pup survival during the first 3 months of life; eight of 21 transmitted pups died of CPV infection in 1992. The potential impact of these canine pathogens on wolves (C. lupus) reintroduced to Yellowstone National Park remains to be documented.

We collected mallards (Anas platyrhynchos) from bottomland hardwood habitats on the Bayou Meto Wildlife Management Area and the White River National Wildlife Refuge, Arkansas County, Arkansas during the winter of 1990 to 1991 to determine if measures of physiological condition could be predicted from structural size, serum metabolite levels, or from direct measures of carcass composition. Serum triglyceride levels were correlated (r = 0.57, P = 0.007) with total body fat in males and slightly increased the value (from R² = 0.64 to 0.76) of intact body mass alone for predicting total body fat in males. Overall, however, serum metabolites appeared to be poor indicators of the magnitude of nutrient masses in mallards. Three potential indices of nutritional status were developed from carcass composition data: protein/total ash, fat/total ash, and fat/fat-free body mass. Protein masses of male mallards changed over winter (P = 0.02). Consequently, fat-free masses are not constant and represent poor indicators of structural size for mallards wintering in the Mississippi Alluvial Valley.

We evaluated the plasma concentration of the acute phase protein haptoglobin (Hp) from Steller sea lions (Eumetopias jubatus) and harbor seals (Phoca vitulina) in regions of Alaska (USA) where the populations of these pinnipeds were declining and compared the values with concentrations of Hp from the same species in areas where the populations were stable. Samples were collected from 1992 through 1994 at sites in Southeast Alaska, Prince William Sound, the Gulf of Alaska, and the Aleutian Islands. Significantly higher levels of Hp were found in the samples from the areas of decline compared to those from stable populations. Based on these findings, we propose that one may be able to distinguish these compromised pinniped populations using Hp as a biomedical indicator.

Twenty free-ranging adult African elephants (Loxodonta africana) in northern Botswana were immobilized with a mean (±SD) of 9.5 ± 0.5 mg etorphine hydrochloride and 2,000 IU hyaluronidase by intramuscular (IM) dart. The mean time to recumbency was 8.7 ± 2.4 min. All animals were maintained in lateral recumbency. The anesthesia monitoring protocol included cardiothoracic auscultation; palpation of auricular pulse for quality and regularity; checking of rectal temperature, and monitoring of respiratory and heart rates. Results of basic physiologic measurements were similar to those of previous field studies of African elephants immobilized with etorphine or etorphine-hyaluronidase. In addition, continuous real-time pulse rate and percent oxygen saturation of hemoglobin (SpO₂) readings were obtained on 16 elephants with a portable pulse oximeter. Duration of pulse oximetry monitoring ranged from 3 to 24 min (mean ±SD = 8.2 ± 4.8 min). Differences between minimum and maximum SpO₂ values for any given elephant ranged from 1 to 6 percentage points, evidence for relatively stable trends. The SpO₂ readings ranged from 70% to 96% among the 16 elephants, with a mean of 87.3 ± 2.8%. Fifteen of 16 elephants monitored with a pulse oximeter had mean SpO₂ values ≥81 ± 2.4%, with 11 having mean Sp SpO₂ values ≥85 ± 1.5%. All 20 animals recovered uneventfully following reversal: diprenorphine at 23.3 ± 1.5 mg intravenous (IV) with 11.7 ± 0.5 mg IM, or 24 mg diprenorphine given all IV.

A disfiguring shell disease was detected in river cooters (Pseudemys concinna) and yellow-bellied turtles (Trachemys scripta) from Lake Blackshear, Georgia (USA). The turtles used were part of a mark-recapture study conducted from September 1991 to June 1993. Histologic changes on four turtles included acute segmental necrosis of the epidermis, followed by ulceration, necrosis of the underlying dermis and dermal bone, and exaggerated remodeling of bone. Additional findings included visceral inflammatory lesions and bacterial infection, sepsis, and marked trematode ova granulomatosis. The cause of the shell lesions was not determined.

Clinical signs of impaired vision or neurological disease occurred in seven of 74 free-living moose (Alces alces) from Saskatchewan, Canada, submitted for necropsy between 1969 and 1994. Several lesions were found in each eye, including retinal degeneration (seven cases), cataract (six cases), lymphocytic-plasmacytic anterior uveitis (six cases), corneal scars (six cases), keratitis (four cases), and microphthalmia (one case), but their cause was not determined. Moraxella bovis was isolated from the cornea of one moose. Lesions in the brain and spinal cord were mild or absent.

High prevalences of hindlimb deformities were recorded in wild-caught green frogs (Rana clamitans), northern leopard frogs (Rana pipiens), American toads (Bufo americanus), and bullfrogs (Rana catesbeiana) from agricultural sites exposed to pesticide runoff in the St. Lawrence River Valley of Québec, Canada, between July and September 1992 and 1993. Of 853 metamorphosing anurans examined in 14 farmland habitats, 106 (12%; range 0 to 69%) had severe degrees of ectromelia and ectrodactyly, compared to only two (0.7%; range 0 to 7.7%) of 271 in 12 control sites. However, the variation in the proportion of deformities among sites was too large to conclude that there was a significant difference between control and pesticide-exposed habitats. Clinical signs varied and were characterized by segmental hypoplasia or agenesis of affected limbs. Conspicuous abnormalities interfered with swimming and hopping, and likely constituted a survival handicap. Because of circumstances and the frequency of these malformations in nine distinct habitats, and in three different species from one of our study sites, we propose a teratogenic action of exogenous factors. Despite the fact that many biotic and abiotic agents are potentially harmful to limb development, agricultural contaminants were suspected as primary aggressors. Thus, clinical examination and frequency of deformities in anurans might be an economical screening tool to assess ecosystem health and the presence of environmental contaminants.

The gross and microscopic pathology of a fungal septicaemia caused by the zygomycete, Mucor amphibiorum in 27 free-ranging cane toads, Bufo marinus, in Australia is described. Seven of the 27 toads had clinical signs of illness when discovered and five of these seven were moribund. Multiple granulomas were found in many organs, and in massive infections granulomas tended to coalesce. Liver, spleen, kidneys, urinary bladder, heart and lung were most commonly involved, but granulomas also occurred in subcutaneous lymph spaces, skin, gastrointestinal tract, voluntary muscle, bone, cranial cavity and the oral cavity. Single lesions appeared grossly as a lemon coloured nodule ≤5 mm in diameter. Histologically, the primary lesion was a granuloma composed of multinucleate giant cells, macrophages, occasional lymphocytes and eosinophils surrounding the distinctive sphaerules of M. amphibiorum. Fibroblasts occurred in greater numbers at the periphery and collagen formed a dense fibrous capsule around some nodules. A less common lesion resembled a microabscess and consisted of mononuclear cells, neutrophils and eosinophils surrounded by macrophages. Many of the centrally placed mixed inflammatory cells appeared necrotic. This reaction appeared to be more acute. Both types of lesions sometimes occurred concurrently, but the latter was less common. The pattern of lesions and natural history of M. amphibiorum suggested that ingestion of contaminated soil may have been the route of infection.

We evaluated the response of white-tailed deer (WTD) (Odocoileus virginianus) to dietary aflatoxin. Fourteen 4-to-5-mo-old WTD were used in this 8-wk study, conducted between November 1993 and January 1994. Seven animals received a ration containing 800 parts per billion (ppb) total aflatoxin (AF). Seven control animals received the same ration without AF. At 0, 1, 3, 6 and 8 wk, feed consumption, feed conversion, liver enzymes, bile acid levels, and immune function via lymphocyte proliferation assays and delayed type hypersensitivity reactions were determined. At the conclusion of the 8-wk feeding trial, deer were euthanized and necropsied. Clinical illness was not evident in any of the animals, but by the end of the study, AF-fed deer had reduced feed consumption and body weight as compared to control deer; the differences were not statistically significant. The AF-exposed group had a significant increase (P = 0.03) in serum bile acid concentration as compared to control deer. Two AF-exposed deer had gross and histologic hepatic lesions indicative of a mild degenerative hepatopathy. Residues of an aflatoxin metabolite, aflatoxin M₁, were found in the livers of all treated animals. No differences in immune function were detected between the two groups. We conclude that consumption of 800 ppb AF in the diet of young WTD over an 8-wk period can produce subclinical hepatic injury.

Ten muskrats (Ondatra zibethicus) each were infected with 17,000 eggs (long-term study) and eight muskrats each were infected with 8,000 eggs (short-term study) of Capillaria hepatica (Nematoda). Food intake, body weight, and selected clinicopathological parameters were measured every 2 days for 28 days in the short-term study and every 14 days for 184 days in the long-term study. Muskrats in the short-term study had moderate to severe necrotizing granulomatous hepatitis associated with mild anorexia and weight loss, varying degrees of leukocytosis with eosinophilia and elevation of serum alanine and aspartate aminotransferases. No significant changes in packed cell volume, hemoglobin, total plasma protein, albumin, blood urea nitrogen, bilirubin, lactate dehydrogenase or alkaline phosphatase were found among animals from the short-term study. Muskrats in the long-term study had severe necrotizing granulomatous hepatitis associated with marked anorexia, weight loss and 60% mortality over 39 days post-inoculation (PI); animals that survived for 184 days did not return to pre-inoculation body weights despite returning to normal food intake. Hepatic lesions at 184 days PI consisted of minimal to severe liver replacement by C. hepatica eggs. No statistically significant differences in values of clinical parameters between inoculated animals and a non-inoculated control group from the long term study were found.

During November 1992 to March 1993, and November 1993 to February 1994, 106 greater flamingos (Phoenicopterus ruber) were collected dead or moribund in the wetlands of El Fondo and Salinas de Santa Pola, eastern Spain. Birds still alive were emaciated and had a bile-stained diarrhea. On necropsy, they had liquid in the upper digestive tract and the walls of their gizzards were stained dark green. Fifty-three (93%) of 57 gizzards examined contained lead shot (range one to 277 shot), and fifty-five (96%) of 57 livers contained levels of lead greater than 5 μg/g dry weight (DW) (median = 192.3 μg/g DW, range <2.5 to 992.2 μg/g DW).

A captive bottlenose dolphin (Tursiops truncatus) in a dolphinarium in Tel Aviv, Israel, had signs of anorexia, weight loss and a reluctance to train over a 4-week period in June 1995 and died shortly thereafter. On necropsy, it had an enlarged, yellow discolored liver, and about 55 air gun pellets in the second stomach. The pellets were composed of 40% lead. Samples of liver and kidney cortex contained 3.6 and 4.2 μg/g lead, respectively. There was hemosiderosis in the liver and kidneys, status spongiosus in the brain, and vacuolization in the optic nerve; acid-fast intranuclear inclusion bodies were seen in the kidneys. We propose that chronic lead toxicosis had been induced after the gradual dissolution of the lead-based pellets in the acid environment of the stomach.

In November 1995, a malignant mast cell tumor (mastocytoma) was diagnosed in an adult African hedgehog (Atelerix albiventris) from a zoological park (West Lafayette, Indiana, USA). The primary mast cell tumor presented as a firm subcutaneous mass along the ventrum of the neck. Metastasis to the right submandibular lymph node occurred.

The blood-containing fluids in the thoracic cavity or blood from the heart from 177 red foxes (Vulpes vulpes) in Slovenia were evaluated for rabies antibodies by rapid fluorescent focus inhibition test (RFFIT) and an adapted indirect immunofluorescent test (IIF) in 1994. We evaluated the usefulness of anti-dog fluorescein-isothiocyanate (FITC) conjugate instead of anti-fox FITC conjugate in detection of antibodies against rabies virus in fox sera. In the RFFIT test, 92 (52%) of the fox samples were positive and 70 (40%) samples were negative for rabies antibodies; 15 (8.5%) samples were not suitable for examination in this test. In the IIF test, 98 (55%) fox samples were positive and 79 (45%) sera were negative. The IIF test was suitable for the rapid detection of antibodies against rabies virus in foxes, as often required for vaccine efficacy trials.

From August 1993 to June 1994, 3 month-old bison (Bison bison) were vaccinated with Brucella abortus strain RB51 (SRB51, n = 6), strain 19 (S19, n = 3), or with saline (n = 1) and serologic responses and persistence of vaccine strains within lymph nodes were monitored. Bison vaccinated with S19 had granulomatous lymphadenitis and greater peak numbers of B. abortus than those vaccinated with SRB51. Bison vaccinated with RB51 had similar histological lesions and B. abortus were still present in lymph nodes at 16 weeks. Although antibodies against RB51 were produced, standard tube agglutination test responses of RB51-vaccinates remained negative. The histological lesions of B. abortus infections in bison were similar to those observed in cattle, but bison did not clear SRB51 as rapidly as cattle.

Ninety-five (97%) of 98 black siskins (Carduelis atrata) died within 2 months of arrival in Italy from South America with the following clinical signs: rapid weight loss, breast muscle atrophy, congested and distended abdomen, diarrhea, and lethargy. Macroscopically we observed hepato-splenomegaly, pulmonary congestion, and thickening of the interstinal wall. Histologically, lymphomonocytic transmural enteritis, interstitial mononuclear cell infiltrates in the lungs and in the liver, as well as activation of splenic follicles were common features. Large numbers of protozoa belonging to Isospora sp. were observed in various stages of their life-cycle in the intestinal epithelium, and some zoites were found in the extra-intestinal cellular infiltrate as well. No viral or bacterial pathogens were found.

During a telemetry study conducted between 1993 and 1995 in east-central Kansas (USA) on northern bobwhite (Colinus virginianus) populations, a wild adult male quail was found with signs of disorientation and torticollis in August 1994 in Lyon County, Kansas. Based on histological and parasitological examination, it was determined that the bird was infected with larval nematodes of the genus Baylisascaris spp. This is the first known recorded case of Baylisascaris sp. in a wild game bird species.

A 1:1 mg mixture of Telazol® and xylazine hydrochloride (100 mg of Telazol® and 100 mg of xylazine per ml) was used to immohilize wild collared peccaries (Tayassu tajacu) and feral hogs (Sus scrofa); mean (±SD) intramuscular dosage rate was 4.73 ± 0.86 mg/kg and 4.35 ± 0.68 mg/kg for peccaries (n = 107) and hogs (n = 49), respectively. Mean (±SD) induction time (time from injection until complete immobilization) was 4.6 ± 2.5 minutes for collared peccaries and 4.4 ± 1.9 for hogs. Peccaries became conscious at 64 ± 29 minutes and first stood at 92 ± 33 minutes after initial injection. Hogs became conscious at 54 ± 26 minutes and first stood at 78 ± 38 minutes after initial injection. A 1:1 mg mixture of Telazol® and xylazine provided an effective and safe method to immobilize both species and provided adequate analgesia and anesthesia for short surgical procedures.

A combination of ketamine hydrochloride and xylazine hydrochloride at doses of 50 mg/kg and 5 mg/kg, respectively, was used to immobilize 48 muskrats (Ondatra zibethicus) from October 1993 to November 1994 in Tennessee (USA). Mean (±SD) time for induction was 2.97 ± 1.1 min. After a mean (±SD) duration of 27.2 ± 3.5 min intramuscular yohimbine hydrochloride at a dose of 0.125 mg/kg was administered. Mean (±SD) recovery time was 48.1 ± 21.6 min. All anesthetic inductions were smooth and sufficient depth of anesthesia was achieved to allow surgical collection of adipose tissue. Recovery times were more variable than expected. There was a significant (P ≤ 0.05) drop in heart rate, respiratory rate, and body temperature during anesthesia. One animal died during recover).