Marble spleen disease (MSD) is a contagious disease of captive-reared ring-necked pheasants (Phasianus colchicus) characterized by variable mortality and high morbidity. The etiologic agent is a type II avian adenovirus closely related to hemorrhagic enteritis virus of turkeys and splenomegaly virus of chickens. Gross lesions of MSD consist of enlargement and mottling of the spleen and pulmonary edema. Microscopic alterations are most pronounced in the spleen and are characterized by reticuloendothelial (RE) cell hyperplasia and lymphoid necrosis. Intranuclear viral inclusions occur within hyperplastic RE cells. Serologic detection of MSD is routinely accomplished using an agar gel precipitin test. Oral vaccination with hemorrhagic enteritis virus or avirulent strains of MSD virus is effective in preventing MSD. There is no specific treatment available for MSD but supportive care, strict sanitation and good management practices are helpful in reducing mortalities and limiting the spread of an epizootic.

The prevalence of gall stones (100% cholesterol) in a deer mouse (Peromyscus maniculatus) population located in Siskiyou County, California (USA) was studied on a monthly basis from February 1985 through January 1988. During each year we documented a pronounced annual cyclicity with peak prevalence (31 to 53%) during the winter and low prevalence (2 to 3%) during late summer. Gall stone prevalence was not related to sex or age of the animal. The earliest onset of gall stone production and the maximum prevalence achieved were associated with the greatest abundance of deer mice; lower levels of population abundance were associated with later onset of gall stone production and lower peak prevalences. This association of gall stone prevalence with both season and population abundance levels suggests that the causative factor(s) is/are related to the quality and availability of the diet.

Survival, growth rates, body size and fertility of wild caught Norway rats (Rattus norvegicus), infected and uninfected with a Hantavirus (antigenically related to Seoul virus), were compared. No differences were found in the survival of seronegative versus seropositive rats, as measured by mark–recapture experiments. Growth rates, as measured by weight gain but not by increased body length, were slower in seropositive, sexually mature (>200 g) rats, although no differences in the ultimate body size of infected versus uninfected rats were found. No differences in external measures of sexual maturity, or in embryo counts or testes sizes, were found for infected versus uninfected rats. We conclude that hantaviral infections have little or no impact on demographic processes in Norway rat populations.

In this study, 20 laboratory reared Onychomys leucogaster from a parental population that is naturally exposed to plague were each fed a white mouse that had been inoculated with Yersinia pestis. Three of the 20 O. leucogaster died, four survived with antibody titers against Y. pestis and 13 survived with no titer against Y. pestis. In contrast, when 20 O. leucogaster from a plague naive parental population were fed infected prey, seven died and 13 survived with no antibody titer against Y. pestis. Our results suggest another means by which O. leucogaster from populations that are naturally exposed to plague may acquire the disease.

The involvement of wild birds in western equine encephalitis (WEE) and St. Louis encephalitis (SLE) virus activity in the Red River valley area of North Dakota (USA) during a WEE epidemic was investigated in August 1975. Free-ranging birds were captured with mist nets and nestlings by hand. Virologic and serologic results indicated that a similar rate of WEE virus activity occurred throughout Richland County and between permanent and summer resident birds. The rate of SLE virus activity in the birds of Richland County was lower than for WEE virus, but the SLE antibody prevalence was greater in rural areas than within urban locations. Seven of the nine WEE virus isolations were from nestling birds of four different species; the remaining two from adults of two different species. Overall prevalence of neutralizing (N) antibody against WEE virus was 5% in nestling and 14% in adult birds but was the opposite for N antibody against SLE virus, 17% in nestling and 5% in adult birds. Differences between the two viruses in the presence and persistence of maternal N antibody or differential mortality in nestling birds may have caused the disparity in antibody prevalences.

Adult female and juvenile Mexican free-tailed bats (Tadarida brasiliensis mexicana) were collected bimonthly at Lava Cave, New Mexico from May through September. The purpose of this study was to examine the prevalence of active rabies infection as well as to determine individual immune status in these hosts. All bats were bled and examined for rabies antibody (total antibody versus IgM) utilizing a modified serum neutralization test. The brains were removed and examined by the fluorescent rabies antibody (FRA) test. No significant difference was observed in the number of adults with rabies neutralizing antibody (total) over the study period. Significant differences in rabies neutralizing antibody (total) were observed among the juveniles sampled during July and August. The number of adults with IgM specific antibody was low (15 of 750, 2%) and did not fluctuate significantly. However, the number of juveniles with IgM antibody did show increased levels in August and September. The number of adults positive by the FRA was low (4 of 750, < 1%) and did not appear to fluctuate significantly over the study period. The number of juveniles positive by the FRA was three and one-half times higher than observed for the adults (14 of 600, 2%). These results indicate that the Mexican free-tailed bat appears to be exposed to rabies virus shortly after birth as evident by its immune status. The low prevalence (4 of 750, <1%) of active infection as determined by the FRA and mouse inoculation and the high prevalence (514 of 750, 69%) of IgG antibody in the adult females indicate that the Mexican free-tailed bat recovers from rabies virus infection.

Frog erythrocytic virus (FEV), one of the largest icosahedral viruses, is enveloped, measures up to 450 nm in diameter, and contains double stranded DNA. The virus is found in the cytoplasm of erythrocytes of Rana catesbeiana, Rana septentrionalis, and Rana clamitans from Algonquin Park, Ontario (Canada). Acidophilic inclusions in infected erythrocytes stained with Giemsas stain correspond to viroplasms from which FEV buds and forms aggregates of virus particles as seen in the electron microscope. Frog erythrocytic virus appears to acquire its envelope from lamellar membranes which surround the virus particles. The virus is structurally sensitive to cesium chloride, potassium tartrate and glycerol. It is also sensitive at pH 1 to 5 and a temperature of 56 C for 15 min. The virus contains at least 16 proteins which range in relative molecular mass from 19.5 to 91.0 kilodaltons (kDa), with two major proteins of 31.0 and 43.0 kDa. The viral DNA has a buoyant density of 1.690 ± 0.005 g/ml, guanine plus cytosine ratio of 25 to 36%, and a melting temperature of 82 to 86 C. Data from this study indicate that FEV should be included in the family Iridoviridae.

To evaluate the replication of a highly virulent avian influenza A virus in a potential reservoir host, mallard ducks (Anas platyrhynchos) were inoculated with the virulent strain A/Ty/Ont/7732/66 (H5N9). Viruses recovered from the ducks were analyzed by hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA) and found to possess antigenically altered viral hemagglutinins. Plaque formation on the Madin-Darby Canine Kidney (MDCK) cell line and on primary chicken embryo cells was investigated, and isolates recovered from the ducks differed from the wild type by being unable to form plaques on MDCK cells without trypsin. This phenotype did not appear to be due to inefficient cleavage of the hemagglutinin by host cell proteases since hemagglutinin immunoprecipitated from cell lysates was cleaved. Although the plaquing phenotype suggested attenuation of the isolates from the ducks, they were not significantly altered in their virulence for chickens shown by infectivity studies in vivo. These results indicate that replication of influenza A/Ty/Ont/7732/66 virus in ducks can produce antigenic and phenotypic variants which are still highly virulent for domestic poultry.

Alveolar macrophages were obtained from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) and domestic sheep for the purpose of comparing pulmonary host defense mechanisms in the two species. Specific variables studied included (1) characterization of the cell types present in the lung, (2) alveolar macrophage phagocytic and bactericidal functions, (3) measurement of protein levels in lavage fluid, and (4) measurement of Cortisol levels in lavage fluid. While phagocytic cell populations were similar between bighorn and domestic sheep, a significantly higher percentage of lymphocytes were present in bighorns than domestics (20% in bighorn versus 6% in domestic sheep). Significant differences were not observed in the phagocytic or bactericidal tunctions of macrophages between the two species. Significant differences were not observed in either lavage fluid protein levels or in Cortisol levels.

Pathological findings associated with helminth and arthropod parasites of four wild platypuses (Ornithorhynchus anatinus) are described. Fourth-stage larval rhabditoid nematodes (?Cylindrocorporidae) found partially embedded in the stratum corneum were associated with mild acanthosis, orthokeratotic hyperkeratosis and inconstant subacute dermatits. A filarioid nematode (?Lemdaninae) was found in hypodermal lymphoid tissue. A larval trichostrongyloid nematode was found in the dermis, with no evidence of host response. An undescribed species of trombiculid mite (“chigger”) was found in the pelage and attached to superficial stratum corneum. Focal inclusions of eosinophilic material within stratum corneum, interpreted as mite gel saliva produced during formation of the “stylostome,” were also observed. The tick Ixodes ornithorhynchi punctured the epidermis causing adnexal trauma, dermal haemorrhage and chronic active dermatitis. The digenean Mehlisia ornithorhynchi was present in the small intestine of one animal and was associated with mild catarrhal enteritis.

Fifty cranes, consisting of 46 sandhill (Grus canadensis) and four whooping cranes (Cms americana), were studied. Eighteen sandhill cranes and the four whooping cranes were naturally infected with disseminated visceral coccidiosis (DVC). The remaining sandhill cranes were chicks experimentally infected with oocysts of Eimeria reichenowi and/or E. gruis; five chicks served as controls. There were no clinical signs attributed to respiratory infection. Necropsy of naturally infected adult birds revealed nodules in many organs, including the lung, air sacs, trachea and nares. Artificially infected sandhill cranes and the whooping crane chicks that died from DVC had congestion and consolidated areas in the lung with frothy fluid in the airways. Grossly visible nodules were observed from 10 days postinoculation. Granulomatous pneumonia and tracheitis were observed with light microscopy. Lesions were associated with merogonic and gametogonic stages of eimerian coccidia. Granulomas and granulomatous foci contained parasitized large mononuclear cells. Merogonic stages were seen in lymphoid cells by ultrastructural examination. Oocysts were observed in the trachea and bronchial mucosa and admixed with exudate in the airways, indicating that crane eimerians can complete their life cycle at these sites. Of the few eimeriid coccidia that have extraintestinal stages of development in birds and mammals, only the species in cranes complete their life cycle in both the digestive and respiratory tracts.

Wild turkeys (Meleagris gallopavo) from Pearl River Wildlife Management Area, St. Tammany Parish and from adjacent St. Helena Parish, Louisiana (USA) were observed to have broken and frayed rectrices. The condition was noted in 21% of 90 wild turkeys harvested by hunters during the springs of 1985 through 1988 from the Pearl River Wildlife Management Area. Damage to feathers ranged from mild to severe. Histologic and microbiologic study of five birds disclosed colonization and invasion of the rachis sheath and pulp by fungi of the genera Aspergillus, Curvularia, Cladosporium, Dactylella, Exophiala, Helminthosporium and Trichophyton and by Streptomyces. Sterilized normal rectrices from wild turkeys were inoculated with these organisms and subsequently developed damage that was histologically compatible with field cases. The condition was diagnosed as a multiple etiology mycosis. Successful colonization and invasion of experimentally inoculated feathers required addition of moisture and elevation of relative humidity within the cultures. The apparent high moisture requirements of the fungi suggest that late winter and early spring flooding may be a probable predisposing factor for this condition.

The pathogenicity of a vaccinia recombinant virus expressing the rabies glycoprotein (VVTGgRAB) was tested in several wild animal species which could compete with the natural rabies host, the red fox (Vulpes vulpes) in consuming vaccine baits in Europe. The following species were included in this study, wild boar (Sus scrofa), Eurasian badger (Meles meles), wood mouse (Apodemus sylvaticus), yellow-necked mouse (Apodemus flavicollis), bank vole (Clethrionomys glareolus), common vole (Microtus arvalis), field vole (Microtus agrestis), water vole (Arvicola terrestris), common buzzard (Buteo buteo), kestrel (Falco tinnunculus), carrion crow (Corvus corone), magpie (Pica pica) and jay (Garrulus glandarius). During the observation period, the 107 animals given the VVTGgRAB vaccine orally did not show any clinical signs. Daily monitoring for 28 days and postmortem examination did not result in the detection of pox lesions in the oral mucosa or the skin in mammals or the unfeathered portions of birds. VVTGgRAB seems to multiply in the mammalian species tested, since rabies seroconversion was observed in all of them. Birds failed to develop demonstrable rabies virus-neutralizing antibody. A seroconversion against vaccinia virus was observed in two of four wild boars. Serological results obtained in badgers and wild boars also demonstrates the absence of direct or indirect horizontal transmission oi the recombinant virus. The potential of the recombinant virus for the immunization of badgers against rabies also was investigated. Only 50% of the badgers orally administered with 1 × 10⁸³ TCID₅₀ of this vaccine were protected against rabies.

Unlike previous reports to the contrary, raccoons (Procyon lotor) were successfully vaccinated against rabies with a liquid SAD-B₁₉ attenuated virus vaccine administered per os and given in vaccine-laden baits. There was neither evidence of vaccine-induced rabies in raccoons nor in a limited safety trial with opossums (Didelphis virginiana) given SAD-B₁₉. Protection from lethal street rabies virus infection was not absolute: only three of nine raccoons given 1 × 10⁶⁰ TCID/ml were protected versus five of 10 raccoons given 1 × 10⁷⁰ TCID/ml of SAD-B₁₉ and challenged 4 mo after consumption of vaccine-laden baits. Six of eight raccoons consuming 1 × 10⁸⁸ TCID/ml of SAD-B₁₉ vaccine in baits survived street rabies virus challenge 2 mo postvaccination. Raccoon survivorship was not wholly dependent upon rabies virus-neutralizing antibody titer on the day of challenge. Vaccinated raccoons demonstrated a prominent anamnestic response within 1 wk following challenge. Surviving raccoons were observed for a minimum of 3 mo following street rabies virus challenge with neither clinical nor pathologic evidence of rabies. The SAD-B₁₉ rabies vaccine administered within baits in captivity appears less effective for raccoons than for its demonstrated efficacy in the immunization of free-ranging foxes (Vulpes vulpes) in Europe.

Prior to a limited field application of an orally-administered vaccinia-rabies glycoprotein (V-RG) recombinant virus vaccine for wildlife, background data were obtained for the proposed site on Parramore Island, Virginia (USA). Mammalian target and nontarget species, potentially at risk for exposure to vaccine were inventoried. Placebo baiting trials with a fishmeal polymer bait resulted in high bait disturbance (88 to 100%), primarily by raccoons (Procyon lotor), with infrequent visitation and no evidence of bait consumption by deer (Odocoileus virginianus), small mammals or avian species. Definitive bait acceptance rates by raccoons (indicative of bait ingestion) were difficult to accurately determine based exclusively on premolar and vibrissae samples collected antemortem from live-trapped raccoons for tetracycline and rhodamine B biomarker analyses, respectively. Bait acceptance rate was more accurately determined during a pilot baiting trial conducted on North Island, South Carolina, when mandibles (postmortem samples) were examined for tetracycline incorporation. Parasitologic findings in raccoons on Parramore Island included Hepatozoan procyonis, Phagicola angrense and Physaloptera rata and a variety of incidental microscopic lesions, and provided baseline pathological data for comparison subsequent to V-RG vaccine application. A population density estimate of one raccoon/2.7 ha was calculated using mark–recapture data for comparison after vaccine deployment. Limited reproductive data, including estimates of pregnancy rates by palpation, the number of live kits/litter live-trapped with previously pregnant raccoons or observed in the dens of radio-collared raccoons, was gathered to assess the effect of proposed oral vaccination with V-RG vaccine. Home ranges were assessed by radio-telemetry of 15 raccoons; all radio-collared raccoons currently reside on Parramore Island. Longest straight line distance travelled by raccoons was <2 km, except when animals were translocated and were found to return to their original range.

Serum antibody prevalence of infectious canine hepatitis virus was 12% (90 of 725) for grizzly bears (Vrsus arctos) from Alaska (USA) during the period 1973 to 1987. Prevalence was highest on Kodiak Island at 29% (37 of 127). Prevalence of exposure at individual collection areas did not change significantly over time. There were no significant sex-specific differences in prevalence. Prevalence was directly related to age, but it was 0% for bears <2-yr-old. Young bears which are exposed to the virus may develop clinical disease and die as a result of the infection. This disease may be a factor affecting grizzly bear population dynamics.

Ovarian function was monitored for 33 mo in captive feral mares (Equus caballus) by following serum progesterone (P) levels. A P level >2.0 ng/ml was considered indicative of ovulation. Feral mares were seasonally polyestrus with the majority of animals ovulating between May and October. During the first year after capture, none of the mares ovulated during the anestrous season. However, in subsequent years, approximately 10% of mares ovulated during the months of November, January and February. P levels during the luteal phase of the cycle ranged from 2.0 to 21.0 ng/ml which were similar to levels in domestic breeds of mares. The pattern of P concentrations during pregnancy was also similar to the pattern in domestic mares. These data confirmed the seasonality of ovulation in feral mares but indicated that this seasonality was not as rigid as previously believed. Captive feral mares were similar to domestic breeds in the percentage of mares ovulating all year and in the P levels achieved during the estrous cycle and pregnancy.

Blood plasma cholinesterase (ChE) activity is a sensitive indicator of exposure to organophosphorus and carbamate insecticides. Effects of sex and storage of samples were studied as sources of variability by treating breeding Japanese quail (Coturnix japonica) with 3 mg of dicrotophos or carbofuran per kg of body weight and comparing blood plasma ChE activities for samples collected at 1 hr postdosage and assayed fresh, after 1 and 2 days of refrigeration (4 C), and after 1, 7 and 28 days of freezing(−25 C). ChE activity of fresh control plasma was 34% (P < 0.01) higher in males than females. Male ChE activity remained essentially unchanged during storage while female ChE activity increased (P < 0.05) gradually over time under both storage conditions. In contrast, when plasma ChE activity was inhibited by either antiChE, male plasma ChE activity was depressed further than female ChE (P < 0.01) and remained constant during storage while female ChE activity continued to decrease (P < 0.05). These divergent effects of exposure to antiChE compounds and sample storage indicate extreme care should be exercised in use of blood plasma for evaluation of antiChE exposure in wild birds.

One hundred eighty-one female and thirteen postweanling pup southern elephant seals (Mirounga leonina) were sedated using a combination of ketamine hydrochloride and xylazine hydrochloride. Physiological state had a profound effect on response of the animals to sedation. Physiologically stressed postlactation and postpartum cows had significantly longer periods of sedation than pre-molting females or recently weaned pups. Induction time was not affected by physiological status. Dose rates are recommended for elephant seals in various physiological states.

Pyogruiuilomatous pneumonia was detected in two koalas (Phascolarctos cinereus). Nocardia asteroides was isolated from one koala with extensive pneumonia, pleurisy and splenitis. Staphylococcus epidermidis was isolated from a second koala with pneumonia restricted to the left cranial lobe. Both koalas were in poor condition and had underlying urogenital disease. It was concluded that each organism had acted as an opportunistic pathogen in its compromised host.

An adult, captive European spotted fallow deer (Cervus dama) was submitted for necropsy due to sudden death. Gross lesions consisted of serosanguinous fluid in the thoracic cavity with multiple, often confluent, nodules covering visceral and parietal pleura. Microscopic examination revealed tubular structures lined by cuboidal cells covering a delicate fibrous stroma. Gross and microscopic morphology was consistent with a mesothelioma.

An 11-yr-old female beaver (Castor canadensis) died after a 3½ mo course of intermittent diarrhea, lethargy and anorexia. A postmortem examination revealed both a necrotizing ulcerative colitis and bilaterally enlarged thyroid glands. Histologically, the necrotizing colitis was similar to that caused by canine or feline parvovirus. Thyroid glands were multilobulated. Lobules were composed of irregularly arranged, variably sized follicles, some of which contained colloid. Follicles were lined by a pleomorphic population of tall cuboidal to columnar epithelial cells. Capsular invasion was present. Similar cells, forming follicles were present within the pulmonary parenchyma. This is the first documented case of a thyroid follicular carcinoma with pulmonary metastases in a beaver.

A large, adult male polar bear (Ursus maritimus) was found dead on a barrier island north of Prudhoe Bay, Alaska (USA), in June 1987. There were no external signs of trauma. A twisted distended stomach, distinctive parenchymal and fascial congestion, and significant difficulty in repositioning the anterior abdominal organs, indicated that gastric dilatation-volvulus (GDV) was the proximate cause of death. Polar bears frequently consume large quantities of food at one time and have large stomachs that are well adapted to periodic gorging. The scarcity of food in winter and early spring, combined with voluntary fasting and protracted vigorous activity during the breeding season in late spring may have predisposed this bear to GDV. The relationship between GDV and postprandial exercise emphasizes the need for a better understanding of how the present human invasion of arctic habitats may influence polar bear activities.

Six hundred sixty-one feral swine (Sus scrofa) from Ossabaw Island, Georgia (USA) were captured, bled, and their sera tested for pseudorabies virus (PRV) antibody during a 6 yr period. Prevalence of seroconversion in females was somewhat higher than in males (10% versus 7%), but the difference was not statistically significant. Adults had a significantly higher prevalence than juveniles (29% versus 1%). An important finding in this study was that seroconversion occurred primarily in the adult feral swine.

Approximately 3.5 mo following its capture, a beluga whale (Delphinapterus leucas) developed focal pale gray skin lesions. These lesions persisted for at least 8 mo. A biopsy from one of these sites revealed epithelial intranuclear inclusions. Herpes-like viral particles were seen by transmission electron microscopy. The eventual regression of skin lesions and lack of other clinical signs suggests the virus was only mildly pathogenic in this animal.

Indirect hemagglutination tests on sera from 251 Dall sheep (Ovis dalli) from interior Alaska collected during the period 1979 to 1987 revealed no evidence of exposure to Mycoplasma ovipneumoniae. Apparently, this potentially fatal disease agent has not been introduced into free-ranging Dall sheep populations. In the interest of continued health of such Dall sheep, strict enforcement of domestic animal health regulations and prudent land use practices are clearly indicated.

One hundred five spotted owls (Strix Occidentalis) from seven populations and three subspecies were examined for hematozoa. Hacmoproteus noctuae, H. syrnii, Leucocyto-zoon ziemanni, Trypanosoma avium, Atoxoplasma sp. and unidentified microfilariae were recorded. All northern (S. occidentalis caurina), California (S. occidentalis occidentalis) and Mexican (S. occidentalis lucida) spotted owls were infected with at least one hematozoan; 79% had multiple infections. Twenty-two percent of the owls were infected with as many as four species of parasites. There were significant differences in the prevalence of these species of parasites occurring among the five populations of northern and California spotted owls sampled in California. Haemoproteus noctuae, H. syrnii and Atoxoplasma sp. represented new host records for this host species.

During October and November 1986, Sarcocystis sp. was detected in 24 of 56 (43%) tongues from hunter-killed mountain goats (Oreamnos americanus) in Washington (USA). Sarcocysts had an unusual sessile polyp-shaped branched wall. Mean size of 154 sarcocysts was 71.3 × 37.8 μm (range, 20 to 248 × 10 to 120 μm), and the mean intensity was 2.3 (range, 1 to 28). In an attempt to identify the definitive host, infected tongues were fed to four coyotes (Canis latrans), eight domestic dogs, four domestic cats, three bears (Ursus americanus), two raccoons (Procyon lotor), two martens (Martes americana), two fishers (Martes pennanti), three skunks (Mephitis mephitis), five mink (Mustela vison), five ferrets (Mustela putorius), one pigtail macaque (Macaca nemestrina), two redtailed hawks (Buteo jamaicensis) and one great horned owl (Bubo virginianus). Oocysts or sporocysts were not detected in the feces of any host for ≤20 days after ingestion of the infected meat. The definitive host for Sarcocystis sp. in mountain goats was not identified.

Sarcocysts of Sarcocystis sp. were found in the striated muscles from 11 of 14 wild Florida panthers (Felis concolor coryi) and four of four cougars (two wild F. concolor stanleyana and two captive F. concolor of undetermined subspecies). The common occurrence of sarcocysts in muscles of top carnivores such panthers and cougars is unexplained. This stage of the life cycle is normally confined to the muscles of the prey species. Because large felids are rarely preyed upon, it is unlikely that a species of Sarcocystis has evolved using large cats as intermediate hosts. Therefore, the presence of these sarcocysts might be an indication of immune compromise in these felids, enabling the atypical development of the sarcocysts.

A single adult male river otter (Lutra canadensis) from Louisiana was found naturally infected with Dirofilaria immitis. One adult male nematode was found in the heart; lesions attributable to the presence of the parasite were not found. This is the first report of D. immitis in the river otter in North America.

Wild populations of the sagebrush lizard (Sceloporus graciosus) are reported as paratenic hosts for third stage larvae of Ascarops sp. Larvae were found in stomach submucosal granulomas which averaged 350 μm in diameter and consisted of histiocytes and layers of fibrocytes. Prevalence of infection was 16% (27 of 170 infected); mean intensity was 3 (1 to 8 nematodes/host). Prevalence was significantly higher in male than female lizards.

Reptiles from Southern Province, Zambia were captured and inspected for ticks. Seven of 18 tortoises (Geochelone pardalis) were infested by small numbers of adults and nymphs of Amblyomma marmoreum. Under such circumstances, the tick had little apparent effect on the host. None of the 13 specimens representing four species of snakes examined were infested with ticks.

Ninety-nine mule deer (Odocoileus hemionus) from four Utah counties (Cache, Utah, Sanpete and Sevier) were examined for larvae of Cephenemyia spp. in 1985 and 1986. Numbers of first, second and third stage bot fly instars were related to age, sex, year and geographic location of the mule deer. Fawns and adult deer ≥5.5 yr had a significantly (P ≤ 0.05) higher intensity (x̄ = 37 and x̄ = 68, respectively) of infection than the 1.5- and 2.5-yr-old age groups (x̄ = 19 and x̄ = 26, respectively). Infection by larvae was not significantly different between sexes. Infection was 100% in both years, but the mean intensity was significantly lower in 1986 (P < 0.05). The decline may be related to differences in soil moisture between the 2 years. In 1985, 82% of the deer examined were infected with all three instars. Seventy-seven percent of all first instar larvae were observed in the trachea, usually in the fold immediately posterior to the epiglottis and corniculate cartilages. This new site of attachment for first instar larvae has not previously been recognized.

Repeated outbreaks of infection by psoroptic mange mites (Psoroptes equi var. ovis) affecting most regions of the body and legs were observed in several male white-tailed deer (Odocoileus Virginian us) suffering from hypoandrogenism (e.g., castrates, animals treated with antiandrogens or postprime). The massive infection was characterized by a severe alopecia and skin inflammation and began usually in early winter. One or two spray treatments of a 1% solution of Lindane was usually sufficient to eliminate the clinical signs of the disease and to restore a healthy hair coat. Neither healthy male or female deer have ever exhibited any external signs of this disease nor has the parasite been detected in the scrapings of their skin. We propose a possible relationship between the hormonal status of these animals and their resistance to this parasitic mite infection.

Silastic rods containing either melengestrol acetate (MGA) or levonorgestrel (LN) were placed in anestrous white-tailed deer (Odocoileus virginianus borealis) does to evaluate the contraceptive efficacy of the implants over a 2 yr period. Implants of MGA were placed in five does during mid-pregnancy to evaluate the effect of this treatment on pregnancy, parturition and lactation. Pregnancies were not observed in the five animals implanted with MGA during anestrus. Three of five does implanted with LN became pregnant in the first season. Pregnancy was not interrupted in the five pregnant does implanted with MGA and it was necessary to remove the implants and treat the does with an estrogen to achieve parturition. One of five fawns was delivered alive and was raised by the doe. MGA was effective for 2 yr as a contraceptive in white-tailed deer, LN was ineffective as used, and MGA placed in pregnant does delayed or prevented normal parturition and thus should not be used in pregnant deer.

Injectable all rac-α-tocopherol, at a dose of 12.4 IU/kg body mass, increased circulating levels of α-tocopherol in the black rhinoceros (Bicornis diceros) from 0.18 μg/ml to 1.47 μg/ml within 2 hr. Although the plasma level peaked at Day one (13.07 μg/ml) and dropped rapidly, substantial residual effects were seen even 10 days (1.50 μg/ml) following a single injection. It appears that parenteral vitamin E administration may be suitable for therapeutic treatment of vitamin E deficiency in the black rhinoceros.