In a series of three experiments, isolates of Pasteurella haemolytica biotype A, serotype 2, ribotype reference WSU-1, from healthy domestic sheep, were inoculated intratracheally into eight bighorn sheep (Ovis canadensis canadensis) and seven domestic sheep with doses of bacteria ranging from 5.3 × 10⁸ to 8.6 × 10¹¹ colony forming units. Seven of eight inoculated bighorn sheep died from acute pneumonia within 48 hr of inoculation, whereas all seven domestic sheep inoculated with comparable or greater doses of bacteria remained healthy. One contact control bighorn sheep also died 6 days after its penmates received P. haemolytica. Three other noncontact control bighorn sheep remained healthy during the experiments. Pasteurella haemolytica biotype A, serotype 2, ribotype reference WSU-1 in the inocula was recovered from one or more tissues from all bighorns that died; whereas, it was not detected in any bighorn sheep before inoculation. Three different ribotypes of P. haemolytica A2 were recovered from bighorn sheep; however, only the ribotype reference WSU-1 in the domestic sheep-origin inoculum was recovered from all dead bighorn sheep, and was not recovered from bighorn sheep that survived the experiments. Thus, a relatively nonpathogenic and common isolate of P. haemolytica from healthy domestic sheep was lethal in bighorn sheep under experimental conditions.

Four white-tailed deer (Odocoileus virginianus) were experimentally inoculated with Borrelia burgdorferi to determine serologic response by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Deer had antibodies by ELISA by 2 to 3 wk post inoculation (PI) and remained positive for 10 wk. Deer demonstrated immunoblotting reactivity between 10 and 14 days PI and consistently showed antibody response to nine B. burgdorferi antigens. Attempts were made to recover the spirochete from blood and tissues; B. burgdorferi was isolated from an ear punch biopsy from one of the inoculated deer.

We evaluated the susceptibility of laboratory reared adult and infant white-footed mice (Peromyscus leucopus) to a known pathogenic isolate of Borrelia burgdorferi (N40). Two-month-old and 3-day-old Peromyscus were inoculated intradermally with 10⁶ to 10⁷ spirochetes. At 21 days for adults or 30 days for infants post inoculation, mice were killed, and tissues were cultured for spirochetes and examined microscopically. Based on serology and culture, adult mice became infected but did not have any gross or microscopic lesions. Mice inoculated as infants became infected, and also developed carditis and multifocal arthritis. Contact transmission between inoculated infants and their naive mothers was not observed. Age at inoculation appeared to be a critical factor in inducing Lyme borreliosis lesions in Peromyscus leucopus, as in other species.

We determined the antibody prevalence to Ehrlichia spp., in white-tailed deer (Odocoileus virginianus) and the geographic distribution of seropositive animals in 84 counties in Alabama, Arkansas, Florida, Georgia, Illinois, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia (USA). Using an indirect fluorescent antibody test we detected antibodies (≥ 1:128) to this bacterium in 544 (43%) of 1269 deer. Presence of antibodies to Ehrlichia spp. was related to a southerly latitude, low elevation, and resulting milder climatic conditions. It appears that white-tailed deer were naturally infected with Ehrlichia spp.; the infection was widely distributed throughout the southeastern United States. Based on these data, we propose that white-tailed deer play a role in the natural history of Ehrlichia spp. infection in the United States.

Inclusions characteristic of an infection caused by Toddia sp. were found in the erythrocytes and erythroblasts of 15 of 26 northern water snakes (Nerodia sipedon sipedon) collected near Kingston, Ontario, Canada. Erythrocytes contained translucent inclusions, small acidophilic bodies, and square-shaped crystalloid structures. Erythrocytes infected with Toddia sp. were more rounded than uninfected erythrocytes and had pycnotic nuclei. We observed icosahedral virus particles measuring 195 to 210 nm formed from a membrane-bounded viral assembly site in the cytoplasm of the host erythrocyte. As a result of the viral identity of this parasite, we recommend that the etiologic agent of Toddia sp. infections from this and other species of North American snakes be renamed Snake Erythrocytic Virus.

The first known epizootic of rabbit hemorrhagic disease (RHD) occurred in two free-living wild rabbit (Oryctolagus cuniculus) populations at Doñana National Park, Spain. Rabbit population density was not correlated to RHD mortality. Only adult animals were affected; males and females had similar mortality rates.

Pseudorabies virus was isolated in cell culture from the brain tissue of a 3.5-year-old male Florida panther (Felis concolor coryi). The virus was not isolated from other tissues collected at necropsy. Based upon a nested polymerase chain reaction (PCR), the virus was determined to have the classical wild-type virulent genotype, glycoprotein I (gl ) and thymidine kinase (TK ).

Eight field trials were conducted in 1989 and 1990 in Georgia (USA) and Maryland (USA) to evaluate baits and baiting strategies for delivering oral rabies vaccines to raccoons (Procyon lotor). Bait packets consisting of corn meal and egg batter-based baits enclosed in plastic bags were placed at 1.0-m diameter, raked tracking stations and checked daily. Packets were well accepted by raccoons; they visited 31 to 44% of the tracking stations where they removed 69 to 90% of the packets within 4 to 5 days. All or nearly all baits were removed from plastic bags and less than 1% of the baits were found only partially eaten. No rejection of water-filled paraffin ampules in baits was observed. The use of an odor attractant on bait packets did not appear to enhance bait discovery when packets were placed on raccoon travel routes. An attractant did enhance discovery when baits were placed off-road in a simulated aerial baiting test. Nontarget species comprised 31 to 53% of all visits to the stations; they took 28 to 55% of the baits but did not appear to adversely affect bait availability for raccoons. A total of 2,300 baits, each containing a wax ampule holding 10 mg of a physiological marker (iophenoxic acid), were distributed at a rate of 82 baits/km² on 2,800 ha of Sapelo Island, Georgia. Thirty-five (65%) of 54 raccoons collected following bait placement had eaten one or more baits as indicated by elevated levels of iodine in the blood serum.

A Babesia species isolated from a captive caribou (Rangifer tarandus caribou) with clinical signs of babesiosis and a circulating parasitemia was cultured in vitro. Normal adult caribou erythrocytes supported the growth of the Babesia sp., as did erythrocytes from white-tailed deer (Odocoileus virginianus). Two basal media (M-199 and RPMI-1640) and a defined medium (HL-1) each supplemented with adult bovine serum were compared. The most favorable growth of the parasite occurred in HL-1 medium with 20% adult bovine serum. The morphology of this Babesia sp. isolate shared some characteristics with B. odocoilei and B. divergens.

Serum samples from 176 brown hares (Lepus europaeus P.) shot in three areas of south and central Sweden during 1984 and 1985 were analyzed for antibodies to the protozoan parasite Toxoplasma gondii using several serological assays. No toxoplasma antibodies were detected in any of the sera, either by direct agglutination test or by ELISA, and selected sera were also negative in the IFAT and the Sabin Feldman dye test. Based on the high incidence of acute fatal toxoplasmosis in hares in Scandinavia, we propose that the brown hare is exceptionally susceptible to primary T. gondii infection.

Serum samples from 58 mountain lions (Felis concolor) in California (USA) were collected between April 1987 and February 1990. Nineteen serum samples were used for serum biochemistry determinations; the ranges were similar to reference values in domestic cats, captive exotic felidae and free-ranging mountain lions. A serological survey was conducted to determine whether antibodies were present against selected infectious agents. Fifty-four (93%) of 58 sera had antibodies against feline panleukopenia virus. Fifteen (68%) of 22, 16 (28%) of 58, 11 (19%) of 58, and 10 (17%) of 58 had serum antibodies against feline reovirus, feline coronavirus, feline herpes virus, and feline calicivirus, respectively. Twenty-three (40%) of 58 and 21 (58%) of 36 had serum antibodies against Yersinia pestis and Toxoplasma gondii, respectively. Only one of 22 sera had antibodies against the somatic antigen of Dirofilaria immitis. Feline leukemia virus and feline immunodeficiency virus antigens were not detected in any mountain lion's sera. All 58 sera samples were negative for antibodies to feline immunodeficiency virus and Chlamydia psittaci

Sera from 360 ciconiform and pelecaniform birds collected in Florida (USA) from 1974 to 1990 were tested for serum neutralizing (SN) antibodies to eastern equine encephalitis (EEE), St. Louis encephalitis (SLE), and Everglades (EVE) viruses. Serum neutralizing antibodies to EEE virus were detected in 2%, to SLE virus in 7%, and to EVE virus in none of the samples. Pelecaniform birds (16%) had a higher antibody prevalence (P < 0.02) for SLE virus than did ciconiform birds (5%). Virus could not be isolated from 67 samples. Nestling birds with SN antibodies to both EEE and SLE viruses were found in both fresh water and marine colonies. Antibodies were more prevalent in adult and fledged juvenile birds than in nestlings.

Avocets (Recurvirostra americana) hatched from eggs collected from the south Central Valley of California (USA) were studied to determine the impact of elevated concentrations of selenium, arsenic, and boron on the immune system and growth to maturity. Corcoran ponds were the reference site with low selenium (1.2 ppb) and arsenic (29 ppb) (boron not measured). Westfarmers Pond had elevated concentrations of selenium (319 ppb), arsenic (127 ppb), and boron (109 ppm). Pryse ponds also had elevated selenium, arsenic, and boron concentrations (13.9 ppb, 1,100 ppb, and 29.4 ppm, respectively). Size at hatch was significantly reduced (P < 0.05) in birds from Westfarmers and Pryse ponds. The growth rate was faster, but mean adult size was reduced in birds from Pryse ponds. Avocet chicks from Pryse and Westfarmers ponds exposed solely through in ovo transfer of these elements had significantly increased heterophil: lymphocyte ratios. The phagocytic activity of macrophages also was significantly reduced in these birds, and Pryse Pond birds had an increased proliferative ability of lymphocytes in the presence of concanavalin A, a T-cell mitogen. Avocet chicks (≤5 wk old) were captured from the various ponds and the same morphometric and immune function measurements made. The birds that were most severely impacted by exposure to these compounds were those that were collected from Pryse ponds.

A method to determine erythrocyte cholinesterase (ChE) activity was modified for use in wild mammals. Erythrocyte ChE of California voles (Microtus californicus) was primarily acetylcholinesterase (AChE), which was similar to the brain and unlike plasma which was primarily butyrylcholinesterase (BChE). Triplicate erythrocyte AChE analyses from individual animals of several species of wild rodents revealed a mean coefficient of variation of 8.7% (SD = 4.3%). Erythrocyte ChE activity of several wild mammals of California revealed that mule deer (Odocoileus hemionus) had the highest erythrocyte AChE activity (1,514.5 mU/ml) and dusky-footed woodrats (Neotoma fuscipes) had the lowest activity (524.3 mU/ml). No ChE activity was found in erythrocytes of several species of birds and fish.

Silastic implants containing levonorgestrel (LNG) were evaluated as a contraceptive in captive white-tailed deer (Odocoileus virginianus). Six adult females and six female fawns received either six or nine implants in autumn. Each implant contained 36 mg of LNG. Blood was analyzed by radioimmunoassay to determine LNG release profile for 5 mo post-implantation. Serum LNG concentrations rose significantly (P = 0.0005) 3 days post-implantation, leveled off after 7 days, and did not change (P = 0.5913) during the remaining 5 mo. Mean (±SE) LNG concentrations for all months were higher (P = 0.0377) in adult and fawn females implanted with nine versus six rods (138.1 ± 14.4 versus 56.7 ± 12.3 pg/ml, respectively). Serum LNG levels did not differ between adults and fawns. Five of the six implanted adult females had normal estrous cyclicity; three of these five adult females became pregnant in the first year. Four implanted females (two yearlings and two adults) were monitored during a second year, and housed with a fertile buck; three of them became pregnant. We do not recommend the use of LNG in deer.

We examined the effect of progressive nutritional restriction on acid-base balance in seven captive, adult white-tailed deer (Odocoileus virginianus) from 4 February to 5 May 1988 in north central Minnesota (USA). Metabolic acidosis was indicated by low mean blood pH (7.25 to 7.33) in deer throughout the study. Mean urinary pH values declined (P = 0.020) from a mean (±SE) baseline of 8.3 ± 0.1 to 6.7 ± 0.3 as restriction progressed. Acidemia and aciduria were associated with significant variations in mean blood CO₂ (P = 0.006) and pO₂ (P = 0.032), serum potassium (P = 0.004) concentrations, and with a significant (P = 0.104) handling date × group interaction in urinary potassium : creatinine values. Mean bicarbonate : carbonic acid ratios were consistently below 20:1 during nutritional restriction. Mean packed cell volume increased (P = 0.019) and serum total protein decreased (P = 0.001); thus there was evidence for progressive dehydration and net protein catabolism, respectively. Blood pCO₂, serum sodium, and urinary sodium : creatinine were stable throughout the study. We propose that acidosis and aciduria are metabolic complications associated with nutritional restriction of white-tailed deer.

Free-ranging passerine birds banded at the Mai Po Nature Reserve, Hong Kong, were affected with a skin disease characterized by crusty, proliferative lesions on legs, feet and beaks. Based on retrospective examination of 1990 to 1992 banding records, 83 of 16,353 birds and 5 of 161 species banded at Mai Po were identified as having these lesions. Eurasian tree sparrows (Passer montanus) were most commonly affected (58 of 411 birds) although 19 of 428 black-faced buntings (Emberiza spodocephala), 1 of 43 little buntings (Emberiza pusilla), 3 of 92 spotted doves (Streptopelia chinensis), and 2 of 616 eastern great reed warblers (Acrocephalus orientalis) also had clinical signs of infestation. Adult Eurasian tree sparrows were affected more often than juveniles and males were affected more often than females. Lesions on juveniles usually were on the feet while on adults lesions also were found on legs and beak. The effects of this parasitic infestation on body weight of wild Eurasian tree sparrows was not significant.

Dermatitis associated with natural infestation of a yellow-footed rock wallaby (Petrogale xanthopus xanthopus) with larvae of the chigger mite, Odontacarus (Leogonius) adelaideae is described. This record extends the known host range of O. adelaideae and is the first from a native animal in southern Australia.

A captured gazelle kid (Gazella gazella) held in a mixed herd of sheep and goats in Israel developed the characteristic lesions of contagious ecthyma. Clinical diagnosis was confirmed by electron microscopy and histopathology examinations of infected tissue.

We compared three transport methods for the recovery of Pasteurella haemolytica from pharyngeal swabs collected under field conditions from 42 bighorn sheep (Ovis canadensis) in one captive and three free-ranging populations. Transport methods included: Amies medium with charcoal, transported on ice, and cultured on blood agar within 24 hr; direct plating on blood agar, transported on heating pads, and incubated at 37 C within 8 hr of collection; and phosphate buffered glycerol (PBG), transported on dry ice, and stored at − 70 C for 10 days before culture. Isolates of P. haemolytica were recovered from all 42 bighorn sheep with a mean (±SE) of 1.2 ± 0.1 (Amies), 1.3 ± 0.1 (blood agar), and 1.3 ± 0.1 (PBG) isolates per swab. No statistical differences (P > 0.05) were observed in the recovery of P. haemolytica isolates among the transport methods. However, based on our experience and results of this study, we recommend that if submission of samples to the laboratory is likely to be delayed, pharyngeal swabs be transported in PBG on dry ice and kept frozen until they are cultured. Viable samples can be maintained in PBG at − 70 C for several years.

Four Eimeria species have been reported from American bison (Bison bison): E. auburnensis, E. bovis, E. brasiliensis, and E. canadensis. We report on finding two additional species: E. ellipsoidalis and E. zuernii. In 1993, the prevalence of these six species in 31 yearling bison in a recently-established herd on private ranchland in Montana (USA) was: E. bovis, 97%; E. canadensis, 90%; E. zuernii, 32%; E. ellipsoidalis, 32%; E. auburnensis, 9.7%; and E. brasiliensis, 3.2%. Eimerian oocysts also were recovered from five (14%) of 36 bison in 1993 from West Yellowstone; the species involved were: E. canadensis, E. bovis, E. zuernii and E. auburnensis.

Twenty-one serum samples from 18 wolves (Canis lupus) were collected from 1985 to 1990 from northwestern Montana (USA) and southeastern British Columbia, Canada, and evaluated for antibodies to canine parvovirus (CPV), canine distemper (CD), infectious canine hepatitis, and Lyme disease; we found prevalences of 13 (65%) of 19, five (29%) of 17, seven (36%) of 19, and 0 of 20 wolves for these diseases, respectively. Pups died or disappeared in three of the eight packs studied. In these three packs, adult pack members had CPV titers ≥ 1,600 or CD titers ≥ 1,250. In packs that successfully raised pups, CPV and CD titers were low. We propose that CPV or CD may have caused some pup mortalities.

Prevalence of larval nematodes (Physocephalus sp., Spirurida, Spirocercidae) and associated cysts are reported from the blue spiny lizard, Sceloporus serrifer, from Texas (USA). Prevalence of infection was 29%, with seven of 24 animals infected. Larvae were found in gastric submucosal and occasionally mucosal cysts with a mean (±SE) of 287 ± 9.04 μm in diameter. The nematodes evoked a chronic granulomatous response including cyst formation with focal destruction of gastric glands. Cysts resolved into areas of fibrosis. Sceloporus serrifer is a new host record for Physocephalus sp.

Parasites were collected from 13 Cape mountain zebras (Equus zebra zebra) in the Mountain Zebra National Park, South Africa, during four seasons of 1983 and 1984. Eighteen nematode species belonging to the families Atractidae, Habronematidae, and Strongylidae, and one species of cestode were recovered. The most abundant nematodes were Cyathostomum tetracanthum, Cylicostephanus longiconus and Probstmayria vivipara. Only one of the 10 cyathostome nematodes recovered, C. longiconus was present in every zebra.

An acute necrotizing hepatitis in 1- to 3-wk-old Gambel's quail (Callipepla gambelii) caused by an adenovirus is described. The infection caused high mortality in captive raised, orphan chicks at two wildlife rehabilitation facilities in Arizona (USA). Gross lesions varied from pale livers to multiple, pinpoint, white foci scattered throughout the livers. Microscopically, scattered foci of hepatocellular necrosis were present. Intact hepatocytes at the periphery of necrotic foci had eosinophilic and basophilic intranuclear inclusion bodies.

Postharmostomum gallinum (Trematoda: Digenea; Brachylaimidae) is reported for the second time from the wild turkey (Meleagris gallopavo) in North America. Seventy-six, 14 and three sexually mature specimens, respectively, were removed from the ceca of three of five wild turkeys collected in southeastern New Mexico (USA). Local transmission of this infection was inferred since 10 immature specimens of P. gallinum also were collected from one host. In the turkey with the greatest intensity of mature trematodes, a concurrent hemorrhagic inflammation of the cecum apparently was associated with this infection. Specimens of P. gallinum from these wild turkeys were morphologically indistinguishable from, but their body and egg measurements were larger than, specimens described from the usual Eurasian galliform and columbiform hosts.

A hermaphrodite beluga whale (Delphinapterus leucas) was found in the St. Lawrence Estuary, Quebec, Canada. This animal had two testicles, two separate ovaries, and the complete ducts of each sex; cervix, vagina and vulva were absent. Mature spermatozoa were found in the lumen of seminiferous tubules in the testicles, and numerous involuted corpora lutea were recognized in the ovaries. This represents the first case of true hermaphroditism in a cetacean, and is the fourth hermaphrodite mammal with two testicles and two separate ovaries.

We observed an interstitial cell tumor in an 18-mo-old captive eland bull (Taurotragus oryx) in Tel Aviv, Israel. The histological description of the tumor in the eland was similar to that described in cattle; however, the appearance of a moderate amount of lipid vacuoles in the cytoplasm of the neoplastic cells was uncharacteristic for bovine interstitial cell tumors. The eland also had clinical signs of gynecomastia.