The immunologic effects of lead were measured in game-farm mallards (Anas platyrhynchos) that ingested lead shot while foraging naturally, mallards intubated with lead shot, and unexposed controls. Circulating white blood cells (WBC) declined significantly in male mallards exposed to lead by either natural ingestion or intubation, but not females. Spleen plaque-forming cell (SPFC) counts were significantly lower in mallards intubated with lead pellets compared to controls. Declines in WBC and SPFC means with increasing tissue lead concentrations provide further evidence that lead exposure reduced immunologic cell numbers. Hormonal activity and diet may have influenced the immunologic effects of lead exposure in this study.

The antibody responses of bighorn sheep (Ovis canadensis) infested with Psoroptes sp. mites were investigated by enzyme linked immunosorbent assay on western blots of P. cuniculi antigens. Serum from 20 Psoroptes sp.-infested bighorn sheep (O. canadensis mexicana, O. canadensis nelsoni, O. canadensis canadensis) from New Mexico, Nevada, California, and Idaho reacted strongly with mite antigens ranging from 12 to 34 kd. Serum from 35 Psoroptes sp.-free bighorn sheep of unknown tick infestation status and from three Psoroptes sp.-free bighorn sheep infested with Dermacentor hunteri ticks did not react with these antigens. Psoroptes sp.-specific antibody responses were present throughout a 16 mo period in one infested bighorn sheep, but were not detectable 8 mo following successful treatment. These results demonstrate that specific serodiagnosis of Psoroptes sp. infestation is feasible in bighorn sheep and suggest that antibody responses are indicative of current or recent infestation.

From 1980 to 1983, blood was taken from 60 selected European bison (Bison bonasus) in Poland. Serum samples were tested for the presence of antibodies against Brucella abortus, 14 serovars of Leptospira interrogans, Chlamydia spp., Coxiella burnetii; foot and mouth disease virus, bovine leukemia virus and bovine herpes virus-1. In addition, an attempt was made to isolate bovine herpes virus-1 from the prepuce of selected bulls. Serological tests suggested chlamydial infection in 28 bison, subclinical Q-fever of a 2-yr-old heifer, subclinical bovine leukemia virus infection in a 12-yr-old bull and bovine herpes virus-1 infection in five bulls and three cows. Attempts to isolate bovine herpes virus-1 were not successful. These results suggest the possibility of cross transmission of several of these bovine pathogens between free-ranging bison and domestic cattle in Poland.

Captive raccoons were offered a variety of vaccine containers and bait components in a series of three-choice tests. Paraffin wax ampules were the most readily accepted vaccine container. Preferred bait components included corn and shellfish oils, deep fried corn meal batter, and egg, apple and buttermilk flavorings. These results, together with factors including ease of bait formulation, cost, and suitability for field use, were used to develop an experimental delivery system for an oral rabies vaccine. The developed system was composed of a polyurethane sleeve (1.5 × 5.5 cm) dipped in a commercial food batter mix together with corn meal, milk and egg. The sleeve was deep fried in corn oil and a 2.0 ml ampule containing a recombinant rabies vaccine was then inserted into the sleeve bait. These baits were presented to 10 captive raccoons. Nine of the 10 animals developed high levels of rabies virus neutralizing antibodies. Field tests are needed to determine if the delivery system developed also is effective for wild raccoons.

Normal mean values for hematocrit, hemoglobin concentration, erythrocyte and leukocyte counts, hematimetric indices, erythrocyte dimensions, glucose, urea, uric acid, cholesterol, creatinine, total bilirubin, serum aspartate aminotransferase, serum alanine aminotransferase, alkaline phosphatase, creatinine phosphokinase, lactic dehydrogenase, inorganic phosphorus, chloride, total plasma protein, sodium, potassium, calcium, and magnesium were obtained from the blood or plasma of four Masai ostriches (Struthio camelus) when juveniles at 5 mo of age and as adults 1 yr later in the Barcelona Zoo (Spain). Young ostriches had significantly lower concentrations of hematocrit, hemoglobin concentration, calcium, and magnesium, and higher levels of total protein and potassium, than the adult individuals. The rest of the parameters were not significantly different between the two age groups. The data obtained provide reference values for Masai ostriches.

We examined the concentration of urinary cortisol and urea nitrogen of five hand-reared mule deer (Odocoileus hemionus) fawns that failed to recover from winter starvation, and compared them to levels found in fawns that recovered. The fawns wintered in fenced pastures stocked with wild deer, and were put back on supplemental feed after losing 15% of their body mass. The five fawns that died began receiving supplemental feed up to 3 wk before death. All continued to lose weight, and were consequently removed from the pasture and fed ad libitum 4 to 10 days before death. In the animals that died, cortisol levels continued to increase regardless of food availability, and were correlated with those of urea nitrogen. Postmortem cortisol and urea nitrogen measurements were significantly greater than concentrations found in the weeks preceding death. We hypothesize that uncontrolled protein catabolism is promoted by high levels of cortisol. These cortisol levels may reach a point at which irreversible multiple-system organ failure occurs, leading to the animal's death.

Body size and condition of coyotes (Canis latrans) from a high-density population in Webb County, Texas (USA) were analyzed for age, sex and seasonal differences during 1980 to 1986. Mean body mass was progressively greater for juvenile, yearling and adult coyotes. Males were heavier and longer than females in each age class. Indices of intraperitoneal fat deposits were similar between sexes. Juveniles continued growth from fall to spring. Adults and yearlings both lost intraperitoneal fat overwinter. Mean body mass of adults decreased overwinter but mass of yearlings did not differ significantly between fall and spring. Territorial and transient female coyotes did not differ in mean body mass, length or indices of subcutaneous fat deposits.

Effects of sampling procedures on ability to culture Pasteurella spp. from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) were examined experimentally. Sample site influenced (P < 0.0001) recovery of P. haemolytica in adult bighorn sheep. We isolated nonhemolytic P. haemolytica from 18 of 19 tonsillar swabs and 18 of 19 tonsillar biopsies from adult sheep, yet only four of 19 nasal swabs yielded isolates. Sample handling also affected (P < 0.0001) recovery of P. haemolytica. Nonhemolytic P. haemolytica was cultured from 14 of 19 tonsillar swabs plated directly onto blood agar, but from only two of 19 swabs stored for 24 hr in modified Amies with charcoal; we failed to recover P. haemolytica from any of 19 swabs stored for 24 hr in modified Stuart's medium. We detected nonhemolytic P. haemolytica at least once in bronchial aspirates from four and in nasal swabs from three of six bighorn lambs. Based on direct cultures of tonsillar swabs and/or biopsies, all 26 bighorn sheep (seven lambs, 19 adults) sampled were infected with nonhemolytic P. haemolytica; only two lambs developed pneumonia during the study period. Thirty-four of 37 nonhemolytic P. haemolytica isolates tested were biotype T; three were biotype A. Serotypes 3; 4; 3, 4 and 3, 4, 10 were identified in a subsample of 17 isolates. Our data suggest tonsillar swabs or biopsies plated directly onto blood agar and incubated immediately offer the greatest probability of recovering nonhemolytic P. haemolytica from healthy bighorn sheep.

An oxidase-negative Aeromonas salmonicida was isolated from coho salmon (Oncorhynchus kisutch) suffering from an epizootic of furunculosis at the state hatchery near Belfair, Washington. Typical, oxidase-positive A. salmonicida was isolated concurrently from the same population of fish. Mortality was controlled with medicated feed treatments. Evidence supporting the identification of the two types of A. salmonicida is presented. Methods for the proper identification of oxidase-negative A. salmonicida isolates are evaluated.

Histopathological effects of ectoparasites on integument were examined for a wild population of the side-blotched lizard Uta stansburiana. These included the trombiculid Neotrombicula californica, the pterygosomatid mite Geckobiella texana; the macronyssid mite Ophionyssus natricis (Macronyssidae) and the ixodid tick Ixodes pacificus. A diffuse inflammatory response occurred at the site of chigger and tick attachment which consisted of histiocyte, heterophil, fibroblast and lymphocyte infiltration that often extended into the dermis. Granuloma formation also was noted. The most prevalent parasite was N. californica which frequently occurred in large aggregations above the eyelids. Ectoparasites were most abundant from February through April.

Mycoplasma gallisepticum infection had been confirmed by culture and serology among wild turkeys (Meleagris gallopavo) in close association with domestic fowl on Cumberland Island, Georgia (USA) in 1980. In 1988, wild turkeys were surveyed by serologic and cultural methods for evidence of M. gallisepticum. Chickens (Gallus gallus) and guinea fowl (Numida meleagris) from the site where the disease was originally detected also were tested by serologic and cultural methods for M. gallisepticum infections. There was no conclusive evidence that M. gallisepticum was present in wild turkeys or guinea fowl. In contrast, most chickens were strongly seropositive for M. gallisepticum, suggesting that they had been infected, although the organism was not recovered by cultural or bioassay methods. Other species of Mycoplasma isolated were M. gallopavonis from wild turkeys, M. gallinaceum and M. pullorum from chickens, and M. gallinaceum from guinea fowl. It appears that M. gallisepticum has not persisted or spread in the wild turkey population on Cumberland Island, despite continued contact by some wild turkeys with suspected carrier chickens.

Diverse samples were examined at a site of water-bird mortality, caused by Clostridium botulinum type C toxin in southern Moravia (Czechoslovakia). The toxin was detected in high concentrations in mute swan (Cygnus olor) carcasses (≤1 × 10⁶ LD₅₀/g) as well as in necrophagous larvae and pupae of the blow flies Lucilia sericata and Calliphora vomitoria (≤1 × 10⁵ LD₅₀/g) collected from them. It was detected in lower concentrations (≤1 × 10³ LD₅₀/g) in other invertebrates (ptychopterid fly larvae, leeches, sow-bugs) associated with these carcasses, and occasionally in water samples (8 LD₅₀/ml) close to the carrion. The toxin was not detected in the samples of water, mud or invertebrates collected at a distance ≥5 m from the carcasses. The toxin-bearing larvae of L. sericata and C. vomitoria, containing 80,000 LD₅₀/g of type C toxin, were exposed in the mud at the study site for 131 days from November to March. Although the toxin activity decreased 25-fold and 40-fold in the two samples of maggots exposed during this period, it remained very high (≤3,200 LD₅₀/g). Birds ingesting a relatively low number of these toxic larvae (or pupae) in the spring could receive a lethal dose of the toxin.

Babesia odocoilei from white-tailed deer (Odocoileus virginianus) in Texas (USA) and B. capreoli isolated from sika deer (Cervus nippon) in Ireland were compared morphologically and antigenically. Babesia odocoilei and B. capreoli paired pyriforms resembled each other closely when in sika deer, but B. odocoilei pyriforms in white-tailed deer were slightly different. Babesia odocoilei in white-tailed deer also differed from B. odocoilei and B. capreoli in sika deer in the frequency of its developmental forms. Indirect immunofluorescence antibody test titres showed that there was some antigen cross-reactivity, but not as much as between B. capreoli and the bovine parasite, B. divergens. The Babesia spp. from deer that we studied appear to be distinct but related species. The low infectivity of B. odocoilei for a splenectomised sika deer suggests that sika deer in North America are probably not very susceptible to this parasite in the wild.

Gastropod occurrence and the utilization of habitat by sympatric populations of wapiti (Cervus elephus) and white-tailed deer (Odocoileus virginianus) on range enzootic for meningeal worm (Parelaphostrongylus tenuis) were studied on Cookson Hills Wildlife Management Area (WMA) in eastern Oklahoma. Visual observations and fecal pellet group transect data indicated that wapiti spent the majority of their time in open fields and meadows where we recovered the least numbers of gastropods. Although deer were frequently observed in open areas, visual sightings and transect data indicated that they spent more time in forested areas where we recovered the most gastropods. Gastropods harbored low numbers of P. tenuis larvae (0.00 to 0.06 larvae/gastropod) in all habitat types with the greatest recovery from red oak white oak-hickory forests (0.34 larvae/gastropod). Our results indicate that the reason a viable wapiti herd exists on Cookson Hills WMA in a P. tenuis enzootic area is at least partially because of the habitat preference by wapiti and the reduced availability of infected gastropods in the selected areas prefered by the wapiti. We were not able to detect any free-ranging wapiti that were shedding P. tenuis larvae nor were we able to detect past or sub-clinical infections with P. tenuis in wapiti.

A survey to assess the prevalence of parasitic infections among axis deer (Cervus axis) in three National Parks in India revealed infections with the lungworm Muellerius capillaris. Clinical signs were not evident in infected animals. Therefore, it is suggested that C. axis is probably a carrier of the infection. Under laboratory conditions, terrestrial molluscs (Macrochalamys sp.) were infected with first stage larvae of M. capillaris collected from fecal pellets of C. axis. Feeding of third stage larvae collected from these snails on day 14 post exposure produced patent infections in goats. On day 31 post infection, adult M. capillaris could be collected from the lungs of infected goats. This study establishes the possibility of cross-transmission of M. capillaris between wild and domestic animals in India.

Three hundred forty five adult arctic foxes (Alopex lagopus) from all counties in Iceland were examined for excess cerumen and ear canker mites (Otodectes cynotis) Only 13 foxes (4%) from a single county in northwestern Iceland were infested, where the prevalence of otodectiasis was 38%. Whether or not this parasite is new to the arctic fox in Iceland is unknown. If it is recently introduced, possible sources of infestation are farmed silver foxes (Vulpes vulpes), domestic dogs, domestic or feral cats, and arctic foxes from Greenland. It appears that the rate of transmission between adult foxes is low; a more common route of transmission is probably from the mother to her offspring or between vixens breeding in the same dens in subsequent years by contamination of the dens. No correlation was found between the prevalence of mites in foxes and Samson character.

The activity of acetylcholinesterase (AChE) and the density of muscarinic cholinergic binding receptors (mCBR) were measured in brains from normal Japanese quail (Coturnix coturnix japonica) and from quail after lethal intoxication with diazinon. These were measured in brains from whole heads held at 25 C for 0 to 8 days after death. The maximum relative loss of activity due to post mortem decomposition alone during 8 days was 13% and 10% for AChE and mCBR, respectively. During post mortem decomposition, the ratio of AChE: mCBR activities remained constant at approximately 1.3:1 in normal brains while it was always ≤0.5:1 after intoxication with diazinon. Normal AChE activity could be estimated from mCBR density. Parallel measurement of AChE and mCBR may assist in the post mortem diagnosis of death due to acute poisoning with anti-cholinesterase pesticides when control specimens are not available.

Plasma acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity was measured repeatedly in 27 mallard (Anas platyrhynchos) ducklings between 7 and 85 days of age to determine age-dependent changes in enzyme activity. Plasma AChE, BChE, and total cholinesterase (ChE) activity decreased significantly with age. The relative proportion of AChE in total ChE activity also decreased slightly with age. Since some anti-ChE chemicals can selectively inhibit AChE or BChE activity, characterization of age-dependent changes in the activity of each enzyme may be necessary to accurately identify the occurrence of pesticide exposure.

R51163, a newly synthesized purine alkyl piperidine that produces reliable sedation in cattle, was tested in five adult bull moose (Alces alces) Compared with controls, all animals dosed with 0.4 mg/kg BW ate significantly (P < 0.05) less dry matter for at least 1 wk after treatment. Median estimates of resting metabolism, measured the day of injection. did not differ between treatment and control groups, although the coefficient of variation was almost two times larger for drugged (15%) versus control (8%) individuals. Dose response was allometric, with larger animals exhibiting longer effects.

Cloacal and tracheal swabs were collected from 1,409 hunter-killed ducks in Cameron Parish, Louisiana, during the 1986 and 1987 waterfowl seasons. Thirty avian paramyxoviruses (PMV's) were isolated from 605 blue-winged teal (Anas discors), 75 mottled ducks (A. fulvigula), 375 gad walls (A. strepera), 334 green-winged teal (A. crecca), and 20 mallards (A. platyrhynchos). Prevalence of PMV decreased (P =0.042) from September (4%) through November (2%) to December and January (1%). Juveniles had a higher prevalence of PMV (P < 0.0001) than adults. An isolate from resident mottled ducks documents transmission of PMV's on the coastal wintering areas of Louisiana. The four serotypes isolated, PMV-1, PMV-4, PMV-6, and PMV-8, were typical of PMV's commonly associated with free-living waterfowl.

Investigations of mortalities involving wild mallard ducks (Anas platyrhynchos) revealed the presence of a herpesvirus associated with skin lesions on the plantar surface of the foot web of one duck. Ultrastructurally, the paracrystalline arrays of viral core particles and unencapsidated nucleoids in the nucleus, and the enveloped viruses in cytoplasmic vacuoles are compatible with a herpesvirus. This appears to be the first report of cutaneous lesions in a mallard duck attributable to a herpesvirus. Whether this lesion is due to duck virus enteritis (DVE), suggesting that cutaneous shedding is possible, or due to another uncharacterized herpesvirus of ducks is unclear.

Over a period of 9 yr, seven white-fronted geese (Anser albifrons) and one Canada goose (Branta canadensis) with multiple intramuscular mesenchymal tumors were encountered in Saskatchewan (Canada) and one similarly affected Canada goose was seen on Prince Edward Island (Canada). The tumors in these birds consisted either of adipose tissue, fibroblastic tissue, or a mixture of both types of tissues. The high prevalence of this condition in white-fronted geese suggested a genetic influence.

One hundred twenty-five walleye pollock (Theragra chalcogramma) were collected from Auke Bay, Alaska (USA) in 1985 and examined for histologic evidence of disease-causing infectious agents in 1987. A Goussia sp.-like coccidium was found in the kidney tubules of 75% and an Eimeria sp.-like coccidium was found in the intestine of 18% of the fish examined. The kidney coccidium was associated with sloughing of the tubular epithelium, peritubular fibrosis and granuloma formation. The intestinal coccidium was associated with severe tissue displacement and inflammation. In addition, X-cell pseudotumors were observed in the pseudobranchs (4%), and the fungus Ichthyophonus sp. was observed in the kidney, intestine or brain of 2% of the pollock.

The 1988 fish mortality summary for the catfish (Ictalurus punctatus) industry in Mississippi is presented. In 1988, 2,456 cases were submitted to Mississippi Cooperative Extension Service fish disease laboratories at Belzoni and Stoneville. Bacterial infection caused by Edwardsiella ictaluri was the leading cause of catfish mortality. Descriptions and treatments are presented for bacterial, parasitic, viral and other diseases affecting Mississippi farm-raised catfish in 1988.

Sporulated oocysts and free sporocysts of a Sarcocystis sp. were isolated from the feces of a southern copperhead (Agkistrodon contortrix contortrix) collected in Arkansas (USA). Twenty sporocysts measured 11.2 by 8.5 μm, lacked a Stieda body, and had four sporozoites and a granular sporocyst residuum. Sarcocysts similar to those of Sarcocystis montanaensis were present in the tongues of prairie voles (Microtus ochrogaster) inoculated orally with 800 sporocysts 128 days previously. Sarcocysts were thin-walled, divided into compartments by septa, and had electron dense projections (0.14 μm) on the primary cyst wall. Infection was not pathogenic for prairie voles under the conditions of this study. No infections were observed in ICR strain laboratory mice (Mus musculus) or white-footed mice (Peromyscus leucopus) following oral inoculation of 800 sporocysts.

A protozoan infection (Trichodina truttae) was identified in captive Atlantic salmon (Salmo salar) kelts that died in spring of 1988 and 1989. Fish with intense infections showed signs of listlessness, erratic swimming and in appetence. The infection induced excessive mucus secretion, epithelial sloughing and lesions that probably permitted entry of opportunistic bacteria which eventually caused ulcers and death. A seawater bath for 30 min each week for 4 wk effectively controlled the parasite.

Thirty raccoons (Procyon lotor) from three counties in east-central and southeast Kansas (USA) were examined for schistosomiasis. Eleven (37%) of the raccoons had adult schistosomes identified as Heterobilharzia americana present in the mesenteric vessels, histopathological lesions compatible with schistosomiasis, or both. This represents the first report of H. americana in Kansas and in the central United States.

The prairie rattlesnake (Crotalus viridis viridis) was experimentally infected with tetrathyridia of Mesocestoides sp. Individual snakes were killed at 4 wk increments, and sections of the stomach, small intestine, large intestine and attached mesenteries were examined for nonencapsulated and encapsulated tetrathyridia. Capsule formation was asynchronous with 9 to 80% encapsulated metacestodes. The distribution of tetrathyridia in the wall of all segments of the gastrointestinal tract is presented as evidence that this metacestode is principally a tissue dwelling parasite.

Adult lung nematodes identified as Halocercus lagenorhynchi were collected from the lungs of four Tursiops truncatus calves. The calves ranged in age from newborn to 3-wk-old and were found on both the Atlantic and Gulf coasts of Florida (USA). This finding suggests the possibility of a more cosmopolitan distribution of prenatal infection with lung nematodes in cetaceans than previously suspected.

Wild canid carcasses were obtained during the 1986–1987 and 1987–1988 trapping seasons in Missouri. Hearts and lungs from 293 coyotes (Canis latrans), 85 red foxes (Vulpes vulpes) and 70 gray foxes (Urocyon cinereoargenteus) were examined for Dirofilaria immitis. Age of hosts was determined by radiographic and histologic techniques. Nineteen coyotes (7%) had from 1 to 100 D. immitis and five red foxes (6%) had from 1 to 7 D. immitis, whereas gray foxes had none. This study indicates that heartworm prevalence differs by wild canid species within the same area and during the same time period.

Two of five bobcats (Felis rufus) from southwestern Arkansas had natural pulmonary infections of Paragonimus kellicotti and Filaroides rostratus. Pairs of P. kellicotti were found in spherical cyst-like structures approximately 1 cm in diameter. Filaroides rostratus were seen as serpentine pale white areas on the pleural surface and also firmly embedded in fibrous capsules in the pulmonary parenchyma. Histologic lesions associated with the presence of these parasites consisted primarily of a verminous bronchitis. Clinical signs or compromised pulmonary function were not associated with these infections.

An opossum (Didelphis virginiana) live-trapped on Parramore Island, Virginia was infected with the lung parasite Capillaria didelphis. Lung lesions associated with this parasite were extensive and consisted of numerous areas with central necrosis deep within the parenchyma. Necrotic foci were present around airways and consisted of a mixture of inflammatory cells and cellular debris, adult nematodes and many bipolar eggs. This parasite causes severe verminous pneumonia in the opossum.

Of four species of fish-eating birds from Chiloé Island (Chile), three were infected with eight species of helminths. Tetrabothrius sp. was found in Larus scoresbii. Tetrabothrius cylindracetisy, Profilicollis antarcticus, Anomotaenia dominicanus, Stephanoprora denticulata, Capillaria sp. and P. antarcticus were found in Larus dominicanus. Contracaecum rudolphii and Corynosoma sp. infected Phalacrocorax olivaceus. With the exception of S. denticulata, C. rudolphii and Capillaria sp., the above helminths are reported for the first time from Chile.

Eleven species of ectoparasitic arthropods were collected and identified from ostriches (Struthio camelus) recently imported into the United States from Africa and Europe. Four of these species are reported from ostriches for the first time. The parasites included adult hippoboscid flies (Struthiobosca struthionis) and 10 species of adult ixodid ticks (Amblyomma gemma, A. lepidum, A. variegatum, Haemaphysalis punctata, Hyalomma albiparmatum, H. luscitanicum, H. marginatum rufipes, H. truncatum, Hyalomma sp., and Rhipicephalus turanicus. As a result of these findings, the U.S. Department of Agriculture prohibited further importation into the United States of ostriches and other flightless birds on an interim basis.