A diagnosis of Tyzzer's disease (Bacillus piliformis infection) was made in a group of recently-trapped muskrats (Ondatra zibethica). The major lesions consisted of enteritis and focal necrosis of the liver, with organisms resembling B. piliformis in hepatocytes on the periphery of these foci. The outbreak was associated with recent capture, housing, and the use of sulfaquinoxaline medicated feed.

An epizootic of pneumonia in 20 captive Rocky Mountain bighorn sheep (Ovis canadensis) is described. The sheep were maintained in large paddocks for abcut 9 months after which, in the late summer, the entire herd died within a three week period.

Large numbers of Muellerius adults, eggs and larvae were in the lungs of all sheep. First stage larvae were widely disseminated throughout the lungs and apparently elicited a granulomatous pneumonia. Pasteurella sp. and other bacteria were isolated from the lungs of several sheep but no Chlamydia, Mycoplasma or viral agents were recovered.

Elevated serum fibrinogen levels and normal leukocyte values were found in blood samples taken from several sheep 7-14 days prior to death.

The lungs and gastrointestinal tracts from 18 hunter-killed bighorn rams (Ovis canadensis californiana) were examined in total or in part for helminth parasites during a two-year study of three separate herds in Eastern Oregon. Prevalence was 100% with the lungworm Protostrongylus stilesi. The gastrointestinal fauna from 11 rams comprised Cooperia oncophora, Marshallagia marshalli, Nematodirus oiratianus, Oesophagostomum spp., Ostertagia occidentalis, O. ostertagi, Skrjabinema ovis, Trichostrongylus axei and Trichuris spp. Adult Wyominia tetoni and cysticerci of Taenia hydatigena were recovered from two of six livers examined.

Additionally, searches for potential molluscan intermediate hosts for P. stilesi were conducted on one bighorn range. Snails identified as belonging to the genera Euconulus, Pupilla and Vallonia were found on both the summer and winter ranges.

Rabies virus was detected by fluorescent-antibody and mouse inoculation tests in the brain of one bat, Artibeus jamaicensis, collected at La Tante, Grenada on 19 June 1974. No rabies virus was found in the brains and/or salivary glands of 411 other Grenadian bats of 6 species tested, including 56 A. jamaicensis. Rabies neutralizing antibody was detected by the rapid fluorescent focus inhibition test (RFFIT) in 27 of 353 Grenadian bats. Positives occurred in each of the 6 species sampled, with 40.5% prevalence in A. jamaicensis. In 11 of 86 Trinidadian bats of 4 species known to carry rabies, positive sera occurred only in A. jamaicensis (18.6%) and A. lituratus (8.1%). The potential use of the RFFIT in determining rabies activity is discussed.

Contagious ecthyma has been reported previously from mountain goat (Oreamnos americanus) in one restricted area of eastern British Columbia. A second focus of infection is reported for mountain goat from western British Columbia. Diagnosis was based on appearance of lesions at necropsy, histopathology and demonstration of poxvirus with the electron microscope. The epizootiology of this infection in mountain goat is discussed briefly.

Neurologic disease attributable to Parelaphostrongylus tenuis was diagnosed in five black-tailed deer (Odocoileus hemionus columbianus) relocated from Oregon to Tennessee. Mortality occurred in the pre-release enclosure and in the release area. Infection with P. tenuis was considered the cause of an unsuccessful stocking attempt. In addition, neurologic disease was produced by experimental infection of a black-tailed x white-tailed deer hybrid. Clinical and pathologic findings were described for black-tailed and hybrid deer, and epizootiologic aspects of P. tenuis infections were discussed.

A 4-year study of Northern fur seal (Callorhinus ursinus) leptospirosis in the Bering Sea has shown that in newborn pups Leptospira pomona is associated with a multiple hemorrhage syndrome. Adults may develop an interstitial nephritis and shed organisms in the urine. The herd prevalence, based on microscopic slide agglutination tests, ranged between 7.0% and 15.4% for adult females and 3-4 year old bachelor bulls, whereas nursing pups averaging 4 months of age had a prevalence of 2%. These results are used to conclude that leptospirosis is not acquired primarily on the breeding rookeries but rather is more frequently acquired subsequent to the pups leaving the rookeries, presumably through the food chain during their first pelagic cycle.

Prevalence of neurologic disease attributed to Parelaphostrongylus tenuis was investigated in a population of wapiti (Cervus elaphus canadensis) enclosed in a 2080 ha. preserve. Brains of 44 animals harvested in 1973, 1974 and 1975 were examined grossly and microscopically. Prevalence of infection increased each year from 26.6% of the sample in 1973 to 64.3% in 1975. These data suggest that wapiti living close to white-tailed deer (Odocoileus virginianus) may have a high prevalence of infection, but many individuals may not show signs. Accordingly, routine histologic examination of natural mortality cases without supporting observations of clinical signs would be inadequate to define cause of death. While the effects of the parasite in the population studied did not produce a high herd mortality or a sudden die-off situation, the apparent greater susceptibility of the younger age-classes to the parasite would have a detrimental effect on population recruitment and might limit the growth of wapiti herds living in proximity to white-tailed deer that harbor P. tenuis.

Gross and histopathologic lesions in the eyes of a blind coyote, Canis latrans, collected in King County, Texas are discussed. The animal was in good condition and its age estimated at 7 years. The left globe presented with a superficial corneal erosion, a small punctate erosion, and an apparent lenticular opacity. Histologically, there was a mild anterior uveitis and lenticular degeneration with thickening of the anterior lens capsule, cataractous cortex with Morgagnian globules and bladder cells, and a dense nucleus. The right eye was a firm phthistic globe with thickened extraocular muscles and opaque cornea. Histologically, this presented as an adherent leucoma with partial loss of intraocular contents (retina, iris, and lens), intraocular bone undergoing haematopoiesis, a small granulomatous lesion with foreign body adjacent to the optic nerve in the dural sheath, and gliosis of the optic nerve. The loss of this eye probably resulted from a penetrating injury of the globe with partial loss of intraocular contents. Lesions noted in the eye may be interpreted as an acquired lenticular degeneration of the complicated type.

During February and March, 1974, an epizootic involving lesser scaup (Aythya affinis) occurred in the Tampa Bay area on the west coast of Florida. Several thousand ducks are estimated to have died. Concurrent with this epizootic was a red tide caused by heavy blooms of the toxic dinoflagellate Gymnodinium breve which caused severe wide-spread fish kills. Clinical signs consistent with G. breve intoxication were evident in some of the lesser scaup. A controlled experimental feeding of G. breve toxic material to White Pekin ducklings produced illness and death with signs comparable to some of those seen in the scaup.

Culex nigripalpus experimentally transmitted Plasmodium hermani, a Plasmodium of wild turkeys (Meleagris gallopavo) in Florida. The mosquitoes were infected by feeding upon blood induced parasitemias in domestic turkey poults. The resulting sporozoites, transmitted by either mosquito bites or injection, produced malaria infections in domestic poults.

Muscle from Sarcocystis-infected cottontail rabbits (Sylvilagus floridanus) was fed to coccidia-free cats (Felis domestica) and dogs (Canis familiaris). Only cats became infected and shed sporocysts in their feces. The prepatent period ranged from 10 to 25 days and the patent period from 3 to 46 days. Sporocysts were fully sporulated when shed. They contained 4 sporozoites and a coarse granular residuum and averaged 9.4 by 13.6 μm (N=55). Doses of 200-75,000 sporocysts were orally administered to 5 domestic rabbits (Oryctolagus cuniculus). Domestic rabbits did not become infected, suggesting a strict host specificity for the intermediate host S. floridanus.

Muscle tissue containing grossly visible cysts of Sarcocystis leporum from a cottontail rabbit (Sylvilagus floridanus) was fed to laboratory cats. Sporocysts averaging 13.2 × 9.7 μm were detected in the feces 14 days post-infection and were found until 69 days post-infection.

An infant northern fur seal (Callhorinus ursinus) died in a rookery on St. Paul Island, Pribilof Islands, Alaska. Grossly, slight enlargement of the mesenteric lymph nodes was seen. Microscopically, a lymphosarcoma composed of sheets of monomorphic lymphoid cells in sections of lymph node and tonsil was seen. Electron microscopy of formalin-fixed tissues revealed several structures that were possibly of viral origin in the cytoplasm of the neoplastic cells.

Mycobacteriosis in a Phrynops hilari (side-necked turtle) was characterized by multiple caseating granulomas in the liver and spleen; pulmonary involvement did not occur. Granulomatous inflammation and organisms also were present in the skin, suggesting a cutaneous route of entry with hematogenous spread to visceral organs. Review of the four cases of chelonian mycobacteriosis in the literature indicated that pulmonary tubercules and plastral ulcerations are typical manifestations. The Mycobacterium species usually involved is M. chelonei.

In a recent 2-year period Dermatophilus congolensis infection, ranging from mild to very severe, was found in 15 white-tailed deer (Odocoileus virginianus) taken in southeastern New York State (12) adjacent New Jersey (2) and central Vermont (1). The host range for Dermatophilus congolensis is given.

During fall 1974, approximately 1,000 to 1,500 common crows (Corvus brachyrhynchos) died of aspergillosis in south-central Nebraska. The birds were debilitated, lethargic and dyspneic. On necropsy, typical lesions of aspergillosis were found in the lungs and air sacs. Histopathologic examination revealed granulomatous lesions around fungal hyphae in the respiratory system.

In the spring of 1975, many species of waterfowl and common crows (Corvus brachyrhynchos) were found dead in Phelps County, Nebraska. About 25,000 waterfowl and at least 3,000 crows died in the epornitic. Few waterfowl were seen dying, but the crows experienced a chronic illness during which they became debilitated and were lethargic and dyspneic. Gross and microscopic lesions in the waterfowl were typical for acute avian cholera. The crows had dark, firm areas within the lungs, a loosely adhered yellow fibrous material in the pericardial sac and air sacs and, occasionally, liver abscesses. Microscopically, focal purulent pneumonia was present and a fibrinopurulent exudate overlaid a granulomatous reaction on the heart and lung surfaces. Isolation of Pasteurella multocida serotype 1 confirmed the diagnosis of acute and chronic avian cholera in the waterfowl and crows, respectively.

Postmortem examination of a captive-bred American kestrel (Falco sparverius) showed numerous white necrotic foci 1-2 mm in diameter throughout the liver and spleen. The results of light and electron microscopic studies and experimental transmission to a captive American kestrel and a barred owl (Strix varia) suggests a herpesvirus similar to those dsecribed for owls and other falcons in the U.S. This is the first report of a naturally occurring case of inclusion body disease of falcons in the American kestrel.

A total of 316 anatids (5 species) from Serendip Wildlife Research Station, Lara, Victoria, were examined for blood parasites. Twenty-two of the ducks (all five species) harbored Haemoproteus nettionis and one also harbored Plasmodium relictum. None of 12 dusky moorhens (Gallinula tenebrosa) were infected. There was no significant difference in the prevalence of H. nettionis between species or age groups of ducks. No evidence of infection with Leucocytozoon, Trypanosoma or microfilaria was obtained.

Sporulated oocysts found in the intestines of a Masked Owl (Tyto novaehollandiae) and a Barn Owl (T. alba) produced sarcocysts in mice. Schizonts were found in the livers of 3 mice that died at 7–8 days after dosing.

Neither sarcocysts nor schizonts were found in chickens dosed with oocysts from a Masked Owl.

The rusa deer (Cers'us timorensis) is more resistant to the cattle tick (Boop/iiltis tnicnop/us) than are British breed cattle in Papua New Guinea. The average yield of replete female ticks from deer was 1.6% (0.3–3.2%) as compared to 11.2% (3.4–23.1%) from calves. Ticks from deer were more slender, lighter in weight and produced fewer eggs (mean 1,800) than did ticks from calves (mean 2,200) but the deer was shown to be an effective host. A cervid population can maintain a tick population in the absence of bovine hosts thus presenting an important factor in eradication programs. Nutritional stress appears to result in a