In northern California, antibodies to Borrelia burgdorferi were detected in 58 of 73 (79%), and spirochetemias in one of 26 (4%) black-tailed jackrabbits (Lepus californicus californicus), by indirect and direct immunofluorescence, respectively. Five species of ticks (Dermacentor occidentalis, D. parumapertus, Ixodes neotomae, I. pacificus, and Haemaphysalis leporispalustris) were collected from rabbits. Two of these species of ticks were found to contain spirochetes; two of 10 (20%) I. neotomae and two of 174 (1%) H. leporispalustris. A strain of B. burgdorferi was recovered from I. neotomae. One infected H. leporispalustris female passed spirochetes via eggs to about 67% of her progeny. The widespread distribution of the black-tailed jackrabbit, its infestation by at least four ticks (D. occidentalis, D. parumapertus, I. neotomae, and I. pacificus) known to be infected naturally with B. burgdorferi, and the high prevalence of spirochetal antibody in this lagomorph suggest that it might be useful as a sentinel for surveillance of Lyme borreliosis. Spirochetes were detected in 15% of 40 Columbian black-tailed deer (Odocoileus hemionus columbianus) by direct immunofluorescence bound with a Borrelia -specific monoclonal antibody (H9724), but not with a monoclonal antibody (H5332) specific for B. burgdorferi. The geographical overlap of different borreliae in ticks that bite wildlife such as deer may confound spirochetal serosurveys, and underscores the need for more specific serologic tests than those currently available.

A comparative study of the antibody titer against Francisella tularensis biovar palaearctica in serum and lung extract was made using different immunoassays. Samples were taken from experimentally-infected goshawks (Accipiter gentilis) and European beavers (Castor fiber), and in a held survey of wild beavers. Good accordance between the antibody titer in serum and in lung extract was found in the experimental studies. However, the antibody titer was generally one- to three-fold lower in lung extract than was the titer of serum. Results in the field survey were less reliable. Estimating antibody titer in lung extract is a practical method for surveys for antibody levels, and an alternative to serological surveys, despite lower sensitivity as compared to serum.

Sixteen raptors and three hooded crows were infected experimentally with Francisella tularensis biovar palaearctica. The birds were infected parenterally or per os. One goshawk, one sparrow hawk and one hooded crow died during the experimental period, and the remaining 16 birds were killed 14–77 days after the first infection. Francisella tularensis was not isolated from any bird. Antibody levels against F. tularensis measured in nine birds varied from 0 to 1:1,280. In one goshawk with a titer of 1:1,280, positive fluorescent antibody reactions against F. tularensis were seen in the liver and spleen. These results are similar to those found by other authors indicating that raptors and corvids are normally resistant to infections with F. tularensis.

In vitro and in vivo tests were carried out with tiamulin and gram-negative bacterial pathogens of fish. Determination of minimum inhibitory concentration for 51 strains of seven species of gram-negative bacterial pathogens showed that only strains of Vibrio anguillarum were sensitive at 1.6–6.25 ppm, while the rest of test strains required 25– >100 ppm. Control of infection was not achieved when tiamulin was fed for 14 days at 5 or 50 mg/kg to rainbow trout (Salmo gairdneri) experimentally infected with Yersinia ruckeri.

Thirteen strains of Yersinia spp. were isolated at the Rome zoo and at Castelporziano, a game preserve near Rome. The strains were tested for calcium dependency, autoagglutination, heat-stable toxin production, 50% minimum lethal dose in mice (LD₅₀), pyrazinamidase activity and content of plasmids by electrophoresis in agarose gel. The former three tests were negative for all strains, the LD₅₀, was always ≥1 × 10^{7 6} CFU/ml and pyrazinamidase activity was positive for all strains. Electrophoresis revealed the presence of two plasmids of 27 and 66 megadaltons (MDa) in the two strains of Y. enterocolitica of serotype 027 isolated from animals in the zoo. The two strains of the same species and serotype, isolated from wild animals harboured a 42-MDa plasmid. A small plasmid of 2 MDa was found in two strains of Y. enterocolitica of serotype 07,8 from two subsequent samples of a zoo animal.

One-day-old mallard (Anas platyrhynchos) ducklings were given drinking water for up to 28 days that contained concentrations of sodium and/or magnesium similar to those found in saline wetlands. Growth, tissue development, and biochemical characteristics of these ducklings were compared to those reared on fresh water. Much of the ingested salt was excreted by passage of voluminous fluid excreta. This effect occurred in birds given water with as little as 500 ppm Mg or 1,000 ppm Na. The supraorbital salt gland was active within 4 days in ducklings drinking water containing ≥ 1,500 ppm of Na. Feather growth was decreased in ducklings drinking water with ≥ 1,500 ppm of either Na or Mg. Ducklings drinking water with 3,000 ppm of either ion, or 1,500 ppm of each, grew more slowly than control birds. Ducklings drinking water with 3,000 ppm of either Na or Mg had reduced thymus size and bone breaking strength. Those drinking water with 3,000 ppm of Mg, or 3,100 ppm Na and 1,300 ppm Mg also had less trabecular bone and enlarged adrenals. Birds drinking the latter water had an elevated concentration of Na and calcium, and a decreased concentration of phosphorus and chloride in their serum, and elevated plasma protein levels. Ducklings reared on fresh or slightly saline water adapted very poorly to an abrupt change to more saline water (specific conductivity = 15,250 μmhos/cm) at 14 days of age. These birds stopped eating, became inactive and some died within 3 days; survivors had many tissue and biochemical abnormalities at 20 days of age. The level of salinity in these trials was similar to that in “brackish” or “moderately saline” wetlands and lower than that previously found to have effects on growth and feathering of ducklings. Many of the sublethal effects were subtle and non-specific manifestations of stress, and would be difficult to detect in wild ducklings on saline wetlands.

Water from 10 saline wetlands in Saskatchewan was provided as drinking water for 1-day-old mallards (Anas platyrhynchos). Ducklings given water with conductivity from 3,750 to 7,490 μmhos/cm grew as well as birds on fresh water during a 14-day trial, but birds given water with conductivity of 4,000 μmhos/cm grew poorly during the last 2 wk of a 28-day trial. Ducklings given water with conductivity of 7,720 μmhos/cm grew poorly during a 14-day trial. Six of 10 ducklings given water with conductivity of 20,000 μmhos/cm died, and only two of nine ducklings given water with conductivity of 21,500 μmhos/cm survived 14 days. Survivors were much smaller than controls and had many abnormalities. All ducklings given water with conductivity of 35,000 and 67,000 μmhos/cm died within 60 and 30 hr, respectively. The results indicate that ducklings hatched on many saline wetlands will suffer toxic effects unless they are able to find a source of fresh water shortly after hatching.

Organophosphorous and carbamate pesticides are potent anticholinesterase substances that have killed large numbers of wild birds of various species. Cause of death is diagnosed by demonstration of depressed brain cholinesterase (ChE) activity in combination with chemical detection of anticholinesterase residue in the affected specimen. ChE depression is determined by comparison of the affected specimen to normal ChE activity for a sample of control specimens of the same species, but timely procurement of controls is not always possible. Therefore, a reference file of normal whole brain ChE activity is provided for 48 species of wild birds from North America representing 11 orders and 23 families for use as emergency substitutes in diagnosis of anticholinesterase poisoning. The ChE values, based on 83 sets of wild control specimens from across the United States, are reproducible provided the described procedures are duplicated. Overall, whole brain ChE activity varied nearly three-fold among the 48 species represented, but it was usually similar for closely related species. However, some species were statistically separable in most families and some species of the same genus differed as much as 50%.

Samples of tail muscle from 32 American alligators (Alligator mississippiensis) in Florida were analyzed for contaminant concentrations to provide preliminary information on the potential public health hazard of meat consumption. Detectable levels were found for eight metals; copper, zinc, iron, chromium, mercury, lead, cadmium and arsenic. Mean residue was highest for mercury (geometric mean = 0.61 ppm). DDE, DDD, DDT, dieldrin, heptachlor epoxide, lindane, and PCB's were found. Mean residue concentrations were compared by lake. Alligators appeared to be suitable monitors of environmental pollution. Concentrations of contaminants found in these animals probably pose little threat to public health. However, recommendations must await analysis of larger sample sizes and information on amount and frequency of meat consumption. Alligators killed for human consumption should continue to be monitored for contaminant residues.

Nine young American alligators (Alligator mississippiensis) were injected at monthly intervals with tetracycline to determine the bone apposition rate and the resorption patterns over a 3-mo period. The periosteal apposition rate increased progressively over the 3-mo period from 2.99 μm/day to 5.94 μm/day. Endosteal apposition rate was much slower with incomplete tetracycline lines being observed on the endosteum. This suggests that most modeling-resorptive activities occur on the endosteal envelope.

Blood samples were taken from 23 swift foxes (Vulpes velox) which were to be used in a reintroduction program. The foxes originated from two different captive breeding programs: one at the Calgary Zoo (CZ) and one at the Wildlife Reserve of Western Canada (WRWC). Several differences between swift fox and domestic canine hematology were seen, including an increased number of smaller red blood cells and lower absolute leukocyte counts in swift foxes. Serum glutamic pyruvic transaminase was higher than in the domestic canine normal range while serum creatinine values were lower. Hemoglobin, serum potassium, total protein, globulin in the two groups (CZ and WRWC) were statistically different as were male versus female mean corpuscular volume values.

The effects of dietary protein, fasting, and refeeding on urinary hydroxyproline of nine captive female white-tailed deer (Odocoileus virginianus) were examined from 23 February to 3 May 1984 in northern Minnesota. In the fasted group, mean hydroxyproline: creatinine (OHP:C) was greater (P< 0.05) at week 4 compared to baseline at week 0. Between fasted deer and deer fed high protein-high energy (HPHE) and low protein-high energy (LPHE) diets, no difference in OHP:C ratios was detected during the initial 4 wk of the study. Urinary OHP:C ratios were significantly (P< 0.05) greater in the fasted group during refeeding, concomitant with greater feed consumption and weight gain. There was also a significant (P< 0.02) time effect in the fasted-refed group; OHP:C ratios increased during these two phases of the study. There was no difference between the HPHE and LPHE fed deer in renal OHP excretion. However, mean OHP:C ratios in yearlings (16.8 ± 2.2) were greater (P<0.001) than in the adults (7.5 ± 1.2) of those groups, indicating a higher collagen turnover rate. Urinary OHP:C shows potential as an indicator of growth and starvation, and the data presented may serve as reference values.

The goshawk Accipiter gentilis has recently been reintroduced into parts of Great Britain. During the course of a study of one population, lesions of stomatitis were observed in 14 young from five broods and all the affected birds died. Postmortem examination of three birds revealed live Trichomonas gallinae in exudate from one, and histological findings consistent with a diagnosis of trichomoniasis were made in this and one other bird. It is suggested that trichomoniasis may be a significant mortality factor in goshawks from Britain.

One hundred twenty-three of 300 blood samples (41%) taken from Rio Grande wild turkeys (Meleagris gallopavo intermedia) from three locations in southern Texas (Welder Wildlife Refuge, Chaparrosa Ranch, and Campo Alegre Ranch) and subinoculated into domestic broad-breasted white turkey poults were positive for a Plasmodium (Novyella) sp. Analysis of blood films from 350 turkeys revealed Haemoproteus meleagridis in 76% of the birds. A significantly greater mean parasite intensity was observed in birds from Welder Wildlife Refuge. Birds from the Campo Alegre Ranch exhibited a significantly higher prevalence of H. meleagridis than birds from Chaparrosa. The Plasmodium sp. was infective for canaries (Serinus canaria), bobwhites (Colinus virginianus), and ring-necked pheasants (Phasianus colchicus), but would not produce infection in white leghorn chickens (Gallus gallus) or Coturnix quail (Coturnix coturnix). Attempts to infect Culex tarsalis and C. pipiens pipiens were unsuccessful. Asexual erythrocytic synchrony was not observed when blood-induced infections were monitored in two domestic turkey poults every 4 hr for 72 hr. Exoerythrocytic stages were not found upon examination of impression smears and tissue samples taken from brain, liver, spleen, kidney, lung, and bone marrow. The Plasmodium sp. is most similar morphologically to three species in the subgenus Novyella, P. hexamerium, P. vaughani, and P. kempi. The most striking similarities are to P. hexamerium, and involve mean merozoite number, erythrocytic schizont location, and vertebrate host susceptibility. It differs from P. vaughani in being able to infect turkeys and in type of parasitized erythrocytes. Differences to P. kempi include mean merozoite number, and ability to infect pheasants, and its inability to develop in C. pipiens and C. tarsalis.

The prevalence of Sarcocystis sp. (Protozoa: Sarcocystidae) in fallow deer (Cervus dama) in Tuscany, Italy was determined by digestion technique and histological examination. Forty-four of 45 fallow deer were infected. Infections occurred in adult deer and in fawns. Samples from the heart were more intensively parasitized than samples from tongue, oesophagus and diaphragm muscle. With transmission electron microscopy, the primary cyst wall was folded and formed narrow, overlapping, sinuous projections which were often parallel to the cyst surface. Dogs fed heart samples from infected fallow deer shed sporocysts after 10–11 days. Cats fed the same samples did not shed any sporocysts.

Nine species of helminths, all nematodes, were recovered from the viscera of 48 feral swine (Sus scrofa) from Cumberland Island, Georgia. Both the overdispersed frequency distributions and the abundances of the four common species of helminths (Stephanurus dentatus, Metastrongylus apri, M. pudendotectus and Gongylonema pulchrum) did not vary significantly across the main and interactive effects of host sex and/or seasons. Whether or not the present low population densities of feral swine on Cumberland Island has influenced the pattern of fluctuations in abundances of helminth species across seasons as often observed in helminth communities from other hosts was not resolved. The apparent recent decline in prevalences and abundances, and the loss of certain species from the helminth communities of feral swine on the island may be explained partially by the decreasing transmission potentials of direct life cycle species caused by a recent marked reduction of numbers of individuals in the host population. Conversely, the apparent increased prevalence and abundance of three species of helminths (S. dentatus, M. apri and M. pudendotectus) may be related to their common utilization of earthworms as paratenic or intermediate hosts. Gongylonema pulchrum was the only helminth in which abundances seemed to remain unchanged. This was the only species that was not strictly host specific to feral swine. We found no evidence that helminth infections were responsible for morbidity or mortality in this feral swine population.

At least 3,200 pronghorn (Antilocapra americana) died during a bluetongue (BT) epizootic in eastern Wyoming during late September and early October 1976. In August and September 1984, another BT epizootic occurred in northeastern Wyoming resulting in 300 known pronghorn deaths. In 17 pronghorn examined postmortem, hemorrhages and edema were the most common gross pathologic changes. Microscopic changes included hemorrhage, edema, arterial fibrinoid necrosis, lymphoid depletion in splenic and lymphatic follicles, and neuronal necrosis. Bluetongue virus serotype 17 was isolated from pronghorn in both epizootics. Mortalities ceased with the advent of cool weather in late September and October. Seventy-six of 94 pronghorn killed by hunters during the latter period of the 1976 epizootic, and 14 of 24 pronghorn killed 1 yr later had serologic evidence of exposure to BT virus. The reproductive rate in pronghorn was depressed to 47 fawns per 100 does in August 1977, but returned to 93 fawns per 100 does by 1978. Following the 1984 outbreak, the reproductive rate was similarly depressed, but the cause was confounded by other environmental and range conditions. Deer, mostly mule deer (Odocoileus hemionus), also died during both epizootics of what was presumed to be BT.

An experimental Anaplasma marginale infection was induced in a splenectomized mule deer (Odocoileus hemionus hemionus) which persisted subclinically at least 376 days as detected by subinoculation into susceptible cattle. Anaplasma ovis was experimentally transmitted from sheep to a splenectomized and a spleen-intact mule deer, and back to sheep. The pathogenesis in deer was very similar to that seen in sheep using ovine blood inoculations.

Sera of 43 fallow deer (Cervus dama) of the San Rossore Preserve (Tuscany, Italy) were examined for antibodies against eight pathogens; one proved positive for Brucella sp., 21 for Listeria monocytogenes, 34 for Chlamydia psittaci, three for Coxiella burnetii, one for infectious bovine rhinotracheitis virus, 11 for parainfluenza-3 virus, 25 for bovine viral diarrhea virus and six for bovine respiratory syncytial virus. No age and sex difference in the positivity rates and titers was evidenced, while a sex difference was found both in rates of infection and in titers against parainfluenza-3 virus. Parainfluenza-3 infection was more prevalent in 1984 than in 1983 sampling. Sera of 20 wild boars (Sus scrofa) of the same preserve were examined for antibodies against five pathogens: four sera were positive for Brucella sp., while all were negative for Listeria monocytogenes, Chlamydia psittaci, Coxiella burnetii and Aujeszky's disease virus. Public and animal health involvement with these diseases are discussed for these respective host species.

A skull deformity resulting in death of a herring gull chick (Larus argentatus) is described in detail. The bones of the skull and upper jaw were twisted, assymetrical and of unusual size or absent. The lower jaw had an almost “spoon-like” external appearance and lacked normal articular surfaces.

Cholangiomas found in two of 21 wild-caught white perch (Morone americana) from the Chesapeake Bay are described. The two fish were part of a study investigating a condition of abnormal hepatic copper storage in this species. The tumors were superficial, solitary masses consisting of cuboidal to columnar cells in tubuloglandular arrangement. Mild to marked peribiliary inflammation and fibrosis was seen also. Environmental pollution, the condition of abnormal copper storage, peribiliary fibrosis, and/or parasites may have contributed to the development of these tumors.

Cells closely resembling X-cells were the primary cellular component of a large pseudotumor in the viscera of a black croaker (Cheilotrema saturnum). The fish was captured in coastal waters off San Diego, California and was maintained at the Scripps Aquarium. After 2 years in captivity the fish exhibited extreme abdominal swelling due to a visceral mass, which weighed approximately one-fifth the total body weight. The cells associated with the pseudotumor were identified as X-cells due to their great variability in size, vesicular nuclei which stained negative for DNA and their formation of a pseudotumor. This is the first report of an X-cell pseudotumor in the visceral cavity. We agree with the hypothesis that the X-cell is a protozoan, and the description here of X-cells in a visceral pseudotumor in a fish of the family Sciaenidae associates an additional type of lesion with this enigmatic parasite.

Six cases of severed intestines in farm-raised channel catfish were examined at fish disease diagnostic laboratories in Mississippi and Alabama. This condition has not been reported previously in fish. Affected fish had a 4-7-cm-long intestinal section (hyperemic where it was severed) attached to the stomach. The remainder of the intestine was completely missing in all six cases except for a 1–1.5-cm section of intestine prolapsed from the anus in fish from three of the cases. Ischemia, autodigestion following intussusception, or intestinal epithelium degradation are suggested as possible etiologies for this condition.

A population of American kestrels breeding in southeastern Pennsylvania was examined for hematozoa. Haemoproteus tinnunculi infected 17 of 23 (74%) of the adults. Parasitemia ranged from two to 252, with a median of 32 infected erythrocytes per 10,000. Parasitemia and body weight of female kestrels were negatively correlated. This parasite was not observed in the six juvenile or 38 nestling kestrels examined. Trypanosoma sp. was detected by culture in three of seven (43%) adults, but not in the six juveniles and eight nestlings examined.

Sarcocysts of Sarcocystis odocoileocanis were found in tissue sections of hearts and tongues examined by light microscopy from 30 (88%) of 34 white-tailed deer (Odocoileus virginianus). Hearts were infected less often (13 of 34, 38%) than were tongues (30 of 34, 88%). Sarcocysts of Sarcocystis odoi were not observed in the white-tailed deer examined. A gray fox (Urocyon cinereoargenteus) excreted sporocysts after consuming tongues of white-tailed deer infected with S. odocoileocanis. Two goats inoculated with either 50,000 or 500,000 sporocysts of S. odocoileocanis isolated from the gray fox did not have sarcocysts in tissue sections of the heart, tongue, diaphragm, or esophagus when examined 122 days postinoculation. Dogs fed these tissues from control or inoculated goats did not pass sporocysts in their feces. The present study demonstrates: (1) a high prevalence of S. odocoileocanis infection in white-tailed deer in Alabama, and (2) that goats are not suitable intermediate hosts for S. odocoileocanis.

Five nursing opossums (Didelphis virginiana) were each inoculated with 5 × 10⁶ Cryptosporidium parvum oocysts of calf origin. Following inoculation, endogenous stages of C. parvum were observed in the ileum, cecum, and colon of these opossums. Two of three noninoculated pouch mates acquired infections during the study based on examinations of feces and tissue sections of all eight opossums. Mild diarrhea was observed in four of seven opossums harboring C. parvum, although none died as a result of the infection. Under the conditions of this study, C. parvum appeared to be only mildly pathogenic for opossums.

New host records are reported for Mesocestoides sp. tetrathyridia in two species of iguanid lizards (Cophosaurus texanus and Sceloporus olivaceous) from Texas. Tetrathyridia were found free within the body cavity or encapsulated in the liver of the hosts. Prevalence of infection was generally low, with intensities ranging from 90 to over 200 tetrathyridia per host. In addition, a summary of North American lizard species reported as hosts of Mesocestoides sp. tetrathyridia is presented.

The heart and lungs from 32 adult dingoes (Canis familiaris dingo) were examined for canine heartworm (Dirofilaria immitis) infection. Eighteen of 32 (56%) samples were infected, with intensity of infection ranging from 1 to 31 worms per animal. Seven of 18 (39%) infections were single sex infections. Large numbers of circulating microfilariae were present in blood from all dingoes infected with both sexes of worms.

Blood smears were examined from 143 penguins of four species (Aptenodytes patagonicus, Eudyptes chrysolophus, E. schlegeli, and Pygoscelis gentoo) from Sub-antarctic Macquarie Island and Heard Island. No blood parasites were reported. The vectors of Hepatozoon albatrossi (reported from three species of albatross) are probably shared by penguins, and it is suggested that the latter are not susceptible to infection with this protozoan. Cestodes of the genus Tetrabothrius were present in large numbers in the intestines of 17 Antarctic petrels (Thalassoica antarctica), and evidence is presented indicating that euphausiid crustaceans may be intermediate hosts.

Information was requested on the cause of extensive lesions and death of a black-buck antelope (Antilope cervicapra). Psoroptes cuniculi, the ear mite of domestic rabbits, was identified as the cause of the lesions. Death of the antelope was attributed to a secondary bacterial infection. This is the first report of P. cuniculi on blackbuck antelope. The potential impact of these mites on blackbuck antelope and other exotics in Texas is unknown.

One hundred fifteen wolf (Canis lupus) feces were collected between 1980 and 1984 from northeastern Minnesota and were examined for canine parvovirus by negative contrast electron microscopy. Of these, seven (6%) samples revealed the presence of parvovirus. Some of these viruses were able to grow in cell cultures forming intranuclear inclusion bodies and giant cells.

A herpesvirus-like infection is described in the black-footed penguin (Spheniscus demersus). Clinically, the infection was characterized by debilitation and respiratory distress. Histopathological lesions were confined to the respiratory tract and consisted of inflammation and syncytial cell formation with Type A intranuclear inclusions in sinuses, trachea, and mainstem bronchi. Electron microscopy demonstrated polyhedral viral particles 80–140 nm in size consistent with Herpetoviridae. The lesions resembled those seen in infectious laryngotracheitis.

Actinobacillus capsulatus was isolated from lung, liver, and/or spleen tissue of three snowshoe hares (Lepus americanus) in Alaska. This is the first report of the isolation of this bacterium from free-ranging hares. Actinobacillus capsulatus may have a negative impact on the population density of hares.

Shigellosis due to Shigella dysenteriae was diagnosed in an adult male captive chimpanzee (Pan troglodytes) which died suddenly after a brief recovery from illness lasting at least 3 wk. Confirmatory diagnosis was based on postmortem examination and cultural isolation of Shigella dysenteriae from the intestine, liver, lung, spleen and heart blood.

Eight bobcats with adjoining or overlapping home ranges were examined. Hematological values were within previously reported ranges. Six bobcats demonstrated antibody titers to Toxoplasma gondii. Isospora spp., Taenia taeniaeformis, Spirometra mansoides, Physoloptera rara, Toxocara cati, Strongyloides spp., Trichurus spp., Capillaria spp., and Ancyclostoma spp. were found also in the animals examined. The mean number of parasite species per host was 4.1. All bobcats tested negative for serum antibodies to Rocky Mountain spotted fever (Rickettsia rickettsii). Two bobcats had titers ≤1:20 for tularemia (Francisiella tularensis), and two were positive for leptospirosis (Leptospira spp.).