Comparison of antibodies to Leptospira in white-tailed deer (Odocoileus virginianus) and cattle in Ohio

A survey was conducted to determine the prevalence of leptospiral antibodies in sera from 248 white-tailed deer (Odocoileus virginianus) in Ohio. The sera were collected at check stations during the hunting season in 1983. The microscopic agglutination microtiter test was used to determine the presence of antibodies to Leptospira interrogans serovars pomona, icterohemorrhagiae, canicola, hardjo, and grippotyphosa. Eighteen of 248 (7.3%) serum samples had antibody titers (greater than or equal to 1:100) to at least one of the five serovars tested, with three of these samples reacting to more than one serovar. Prevalence did not differ significantly between sex or age groups. The serovar antigens reacting most frequently with serum antibodies were grippotyphosa (10 of 22, 45.5%) and pomona (eight of 22, 36.4%). Sera agglutinating with pomona antigen had higher titers (ranging from 1:200 to 1:6,400) than did sera agglutinating with the other serovars. These results were compared to results obtained from cattle tested at the Ohio Department of Agriculture Laboratories during 1983. There was a significant relationship between pomona infections detected in deer and cattle (P less than 0.05), but not with grippotyphosa.     

Incidence of leptospiral antibodies in different game species over a 10-year period (1996–2005) in Croatia

During the 10-year survey (1996–2005), a total of 868 blood samples from different game species in Croatia were analyzed for the presence of leptospiral antibodies. The specific antibodies (AB) were detected in 242 samples (27.88%). According to the species in red deer (Cervus elaphus), the antibodies against six different leptospiral serovars were found in 43 of 226 analyzed sera (19.02%). The most frequent antigen serovars in the deer population were Pomona and Ballum (with the same frequency of 23.6%), whereas the highest titer was recorded for serovar Sejroe (1:800). In the analyzed roe deer (Capreolus capreolus) serum samples, a low level of leptospiral antibodies (6.07%) was determined, with just two AB for antigen serovars—Australis and Sejroe. In wild boar (Sus scrofa), leptospiral antibodies were detected in 151 of 431 samples analyzed (35.03%), with AB for nine antigen serovars. The serovars most frequently found were Australis (48.70%) and Pomona (22.70%), and these serovars also recorded the highest titer (1:3,200). Among brown bear (Ursus arctos) samples, leptospiral antibodies were detected in 25.00% of the samples, with four AB for antigen serovars, of which the most frequent was Icterohaemorrhagiae (>40%). This serovar had the highest recorded titer (1:400). From 112 analyzed red fox (Vulpes vulpes) samples, leptospiral antibodies were found in 35 samples (31.25%). The determined antibodies were specific for four antigen serovars, of which the most frequent (46.2%) and with highest titer (1:1600) was serovar Australis. No antibodies (28/0) were recorded in mouflon (Ovis musimon). The most important game species from an epizootiological point of view in the studied area were certainly wild boar and red foxes. With strong serological reactions, these two species could be emphasized as important hosts for Leptospira interrogans sv. Australis in Croatia, but for their declaration as ‘maintaining hosts,’ isolation of sv. Australis is needed. According to aerial distribution, the highest number of positive samples from different game species was recorded in the central and eastern parts of Croatia, known as the ‘historical natural foci’ of leptospirosis—the regions of Posavina, Podravina, Slavonija, and Baranja. In contrast, the areas of Kordun and Gorski Kotar are declared as leptospira low-risk regions for the game species studied.     

A serological survey of Australian wildlife for antibodies to Leptospires of the Hebdomadis serogroup.

A serological survey for antibodies to Leptospira interrograns serovar hardjo was conducted on 574 serum samples from 10 native and 4 introduced wildlife species in south-eastern Australia. The microscopic agglutination (MA) test was used, and titres to hardjo antigen were detected in 33.5% of 352 brushtailed possums (Trichosurus vulpecula) sampled in several areas of Victoria. Prevalence of reactors ranged from 14 to 66% in 4 populations examined intensively. Serovar balcanica was isolated from possums with hardjo antibodies from two different areas. Of 20 wombats Vombatus ursinus) examined in Victoria, antibodies to hardjo were found in sera from 4 and titres to Pyrogenes and Pomona serogroups were detected in another. Hardjo antibodies were demonstrated in sera from 13 of 19 rusa deer (Cervus timorensis). Negative MA test results to hardjo antigens were recorded in 55 mountain possums (T. caninus), 63 macropods (Macropus spp.), 17 water rats (Hydrmys chrysogaster), 39 fallow deer (Dama dama), 2 hog deer (Axis porcinus) and 2 water buffalo (Bubalus bubalus). No MA antibodies to any of 16 leptospiral serogroups were detected in 17 water rats tested. Kidneys were examined from 330 of these animals and focal interstitial nephritis suggestive of leptospirosis was found in kidneys of 63 of 169 T. vulpecula, 3 of 55 T. caninus, 12 of 18 V. ursinus, 6 of 22 Macropus spp., 9 of 16 H. chrysogaster, 5 of 11 C. timorensis and 3 of 39 D. dama. A statistical association between focal interstitial nephritis and MA antibodies to hardjo was found in T. vulpecula.     

Serologic survey of white-tailed deer on Anticosti Island, Quebec for bovine herpesvirus 1, bovine viral diarrhea, and parainfluenza 3.

In 1985 unusual mortality was observed among the 3- to 4-yr-old white-tailed deer (Odocoileus virginianus) on Anticosti Island, Québec (Canada). A viral pathogen was suspected to be the cause of the deaths. Thus, a serologic survey for bovine herpesvirus 1 (BHV-1), bovine viral diarrhea (BVD) virus and parainfluenza-3 (PI-3) virus was conducted. We examined 396 deer sera from 1985. Results indicated that the high mortality mainly afflicted 3- to 4-yr-old deer. In 1985, 57% of deer sampled were seropositive for viral neutralizing antibodies against BHV-1. Prevalences decreased over the next 2 yr of the survey. Prevalence of antibodies against PI-3 virus, determined by hemagglutination inhibition test, remained high (82% to 84%) for the 3 yr period. No deer were seropositive for neutralizing antibodies against BVD virus during the survey period. Analysis of antibodies against BHV-1 and PI-3 viruses according to sex, age and antibody titers revealed that an epizootic BHV-1 infection occurred in 1985; PI-3 infection appears to be enzootic in Anticosti deer.     

Prevalence of antibodies to Neospora caninum in white-tailed deer,Odocoileus virginianus,from the southeastern United States

Serum samples from 305 white-tailed deer (Odocoileus virginianus) from 14 states in the southeastern United States were examined for antibodies to Neospora caninum using a direct agglutination test. Positive agglutination titers were found in 145 (48%) of the white-tailed deer examined: 21 (7%) had titers of 1:25, 92 (30%) had titers of 1:50, and 32 (10%) had titers of > or = 1:500. These findings that antibodies to N. caninum are common in white-tailed deer support the concept that a sylvatic cycle might exist for this economically important parasite of domestic cattle.     

Antibodies to vesicular stomatitis New Jersey type virus in white-tailed deer on Ossabaw Island, Georgia, 1985 to 1989.

From 1985 to 1989, 491 serum samples were collected from white-tailed deer (Odocoileus virginianus) on Ossabaw Island, Georgia (USA) and were tested for neutralizing antibodies to New Jersey and Indiana type vesicular stomatitis viruses. Prevalence of antibodies to vesicular stomatitis New Jersey (VSNJ) virus in deer for the 5-yr period was 43%. Prevalence of antibodies differed by year (P less than 0.0001), and was dependent on age class (P less than 0.0001) and location on the island (P less than 0.0001). Of 173 deer sampled from other locations in the southeastern United States, only two had VSNJ antibody titers normally considered positive (greater than or equal to 1: 32). The positive deer were from Union County, Arkansas (USA) and Wakulla County, Florida (USA). No evidence of exposure to vesicular stomatitis Indiana Virus was observed.     

Serological survey for potential disease agents of free-ranging cervids in six selected national parks from Germany

A total of 164 blood samples, collected from free-ranging red deer (Cervus elaphus), roe deer (Capreolus capreolus) and fallow deer (Dama dama) in six German national parks (NP) between 2000 and 2002, were assayed for antibodies against nine viral disease agents. Antibodies were only detected against the alpha-herpesviruses; specifically, bovine herpesvirus-1 (BHV-1) (22 of 157, 14%), cervid herpesvirus-1 (17 of 157, 10.8%), and caprine herpesvirus-1 (11 of 159, 6.9%). Titers ranged from 4 to 102. Most of the seropositive sera, and those with the highest antibody titers, were from red and roe deer in the Harz and Hochharz NP, which are connected and allow migration between the two. The distribution and specificity of antibodies detected in individual deer suggests that the three alpha-herpesviruses are circulating in these deer populations. No antibodies were detected against bovine viral diarrhea virus, epizootic hemorrhagic disease virus, bovine leukemia virus, bluetongue virus, foot-and-mouth disease virus, or sheep and goat poxvirus.     

Antibodies to granulocytic Ehrlichia in moose, red deer, and roe deer in Norway

Serum samples from 104 moose (Alces alces), 124 red deer (Cervus elaphus) and 114 roe deer (Capreolus capreolus), collected from different counties in southern Norway from 1994 to 2000, were analysed by an indirect immunofluorescent antibody staining method for antibodies to Ehrlichia equi. The overall seroprevalences for granulocytic Ehrlichia spp. in moose, red deer, and roe deer from Ixodes ricinus infested counties were 43%, 55%, and 96%, respectively. Antibody prevalence was significantly higher in roe deer than in moose and red deer (P < 0.001). Mean antibody titers (log10 +/- SD) to E. equi in sera from moose, red deer, and roe deer were 1:1,497 (3.17 +/- 0.646), 1:234 (2.37 +/- 0.424) and 1:676 (2.83 +/- 0.404), respectively. The present work indicates that all these wild ruminant species are exposed to granulocytic Ehrlichia in Norway.     

Disease survey of free-ranging grey brocket deer (Mazama gouazoubira) in the Gran Chaco, Bolivia

Samples from 17 free-ranging hunter-killed grey brocket deer (Mazama gouazoubira) in the Gran Chaco, Bolivia, were collected during June-August 1999. All 17 deer appeared to be in good condition at the time of death. Gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. Serologic tests were positive for antibodies against bovine respiratory syncytial virus and four Leptospira interrogans serovars, with questionable results for epizootic hemorrhagic disease virus serotypes 1 and 2. No antibodies were detected to Anaplasma marginale, Babesia bigemina, Babesia bovis, Babesia odocoilei, bluetongue virus (serotypes 2, 10, 11, 13, and 17), bovine viral diarrhea virus, Brucella abortus, foot-and-mouth disease virus, infectious bovine rhinotracheitis virus, Mycobacterium avium subsp. paratuberculosis, and parainfluenza-3 virus. Sixty-four percent (7/11) of the deer had endoparasites. Amblyomma spp. ticks were found on seven deer, flies of the family Hippoboscidae on six deer, and lice on six deer.     

Characterization of rabbit antibodies for immunochemical detection of<Emphasis Type="Italic">Yersinia enterocolitica</Emphasis>

Rabbit IgG raised against whole cells of Yersinia enterocolitica O:3, O:9 and against a group of pathogenic Y. enterocolitica strains (serotypes O:3, O:5,27, O:8. and O:9) were prepared. The antibody limiting titers were within the range of 1:9.5 x 10(4)-1:7.5 x 10(5). The immunoblotting analysis of Yersinia lipopolysacchides separated by SDS-PAGE showed that IgG against the single serotype O:3 interacted with high-molar-mass LPS of O:3 whereas other antibodies were bound to low-molar-mass LPS of serotypes O:3, O:5,27, O:9 and strain Y. enterocolitica (CNCTC Y 2/68). IgG against the group of pathogenic serotypes also weakly interacted with low-molar-mass LPS of serotypes O:5, O:6,30, and O:10. The cross-reactivity of the antibodies with Y. pseudotuberculosis Ia and/or Y. rohdei b, d, e, f, i, which was observed by means of dot-blotting procedure using the whole bacterial cells as an antigen, was shown not to be caused by LPS of these bacteria. The prepared antibodies were used in the development of indirect competitive ELISA. At the optimum concentration of the immunoreactants the detection limits were within the range of 3-7 x 10(6) colony-forming units per mL.     

Prevalence and isolation of Toxoplasma gondii from white-tailed deer in Alabama

Nineteen white-tailed deer (Odocoileus virginianus) from 5 counties in Alabama were examined for infection with Toxoplasma gondii. Twenty-gram samples of heart tissue were bioassayed in mice, serum was examined for T. gondii antibodies using the direct agglutination test, and sections of heart muscle were examined histologically for tissue cysts. Toxoplasma gondii was isolated from 4 of 19 (21%) white-tailed deer hearts. Antibody titers of greater than or equal to 1:50 were found in sera from 7 of 16 (44%) white-tailed deer. Histological examinations of tissue sections from white-tailed deer hearts were negative for T. gondii.     

Active immunization against gonadotropin‐releasing hormone in female white‐tailed deer

The ability of gonadotropin‐releasing hormone (GnRH) immunization to disrupt estrous cycles in captive white‐tailed deer (Odocoileus virginianus) was tested. Four does were each injected subcutaneously with 1 mg of a GnRH analog‐ovalbumin conjugate, using a diethylaminoethyl (DEAE)‐dextran solution as the adjuvant. Control deer (n = 4) received ovalbumin alone in DEAE‐dextran. The immunization schedule consisted of a primary immunization on 30 December 1994, followed by three booster immunizations at 4‐week intervals. In addition, a booster was administered the following year (3 Nov 1995) before the start of the breeding season. Serum from control females did not contain GnRH antibodies, and estrous cycles of these deer were not disrupted (as determined by serum progesterone concentrations). In contrast, all GnRH‐immunized deer had detectable GnRH antibody titers by 1 week after the first booster. Estrous cycles were disrupted in two of these four deer. The booster given the following year failed to stimulate an increase in mean antibody titers, and all deer began to cycle, including one that had maintained high titers from the previous year. These data suggest that a GnRH analog conjugated to ovalbumin, using DEAE‐dextran as adjuvant, is immunogenic in female white‐tailed deer and may be able to prevent ovulation in some individuals. However, pending further work to increase the immunogenic and biological responses and to decrease the variation among animals, this vaccine does not appear to be an effective means of contraception for deer. Zoo Biol 18:385–396, 1999. © 1999 Wiley‐Liss, Inc.     

Dynamics of maternal antibodies to hemorrhagic disease viruses (Reoviridae: Orbivirus) in white-tailed deer

Enzootic stability, potentially associated with acquired resistance and subsequent transfer of maternal antibodies, innate resistance, or both, has been hypothesized to explain the lack of reports of hemorrhagic disease (HD) in white-tailed deer (Odocoileus virginianus) from Texas. The objectives of this research were to determine the following: how long maternal antibodies to epizootic hemorrhagic disease (EHD) and bluetongue (BT) viruses persist; whether fawns from an enzootic site are naturally exposed to EHD and BT viruses while maternal antibodies are present; and whether field-challenged fawns develop clinical disease. Twelve of 52 fawns from Texas were moved to an indoor facility. All 12 (100%) were positive for maternal antibodies to EHD or BT viruses by agar gel immunodiffusion (AGID) and serum neutralization (SN) tests. Weekly monitoring demonstrated that precipitating antibodies disappeared by 23 wk of age and serum neutralizing antibodies disappeared by 17-18 wk of age. Fawns that remained outdoors in Texas were not observed with signs of HD. At 14-21 wk of age (October), 39 of 40 (98%) fawns that had remained outdoors were positive for EHD and/or BT virus antibodies by AGID and 32 (80%) had SN antibody titers to one or more of five viruses (EHDV-1, EHDV-2, BTV-10, BTV-11, BTV-17). Antibody titers to EHDV-1, EHDV-2, and BTV-11 all exceeded titers of same-age indoor fawns, suggesting recent exposure. Epizootic hemorrhagic disease viruses were isolated from seven (18%) of the outdoor fawns and all 40 remained clinically normal. Natural exposure of deer to EHD and BT viruses occurred at this site in the presence of maternal antibodies without causing disease. This may be due to acquired immunity and the subsequent transfer of maternal antibodies, but it does not exclude innate resistance as a possible factor in the enzootic stability of EHD and BT viruses at this location.     

Antibodies to marine caliciviruses in the Pacific walrus (Odobenus rosmarus divergens Illiger)

Sera from 155 Pacific walruses (Odobenus rosmarus divergens Illiger), sampled in the Chukchi Sea during the summer of 1983, were tested for serum neutralizing (SN) antibodies to six marine calicivirus serotypes. Serotypes tested included San Miguel sea lion virus (SMSV) types 1, 5, 8, and 10, previously isolated from northern fur seals (Callorhinus ursinus Linné) in the Bering Sea; walrus calicivirus (WCV), previously isolated from walrus feces collected off sea ice in the Chukchi Sea; and Tillamook calicivirus (TCV), a bovine isolate from Oregon of suspected marine origin. No antibodies were found to SMSV-1, SMSV-10, or TCV. Antibodies to SMSV-5 were found in two animals (titers 1:20 and 1:160); antibodies to SMSV-8 were found in four animals (all 1:20); and antibodies to WCV were found in one animal (titer 1:40). Antibodies to WCV have been found in the Pacific walrus previously; however, this represents the first report of antibodies to any of the SMSV serotypes in this marine mammal.     

A serologic survey of mule deer and elk in Utah.

Sera from mule deer (Odocoileus hemionus) and elk (Cervus canadensis) in central and northern Utah were tested for the prevalence of antibodies to 11 diseases communicable to man or domestic livestock. Antibodies to Francisella tularensis (at 1:20) were found in 47 of 88 (53.4%) elk and 1 of 89 (1.1%) deer. A screening slide agglutination test for titers to Brucella (at 1:20) showed two reactors in elk but none in deer sera. No positive antibody titers were obtained in tests for anaplasmosis, Colorado tick fever, Rocky Mountain spotted fever, Q-fever, psittacosis, Powassan, western equine encephalitis, St. Louis encephalitis and California encephalitis.     

Antibodies to bluetongue and epizootic hemorrhagic disease viruses from white-tailed deer blood samples dried on paper strips.

The feasibility of using dried blood samples for serologic testing of white-tailed deer (Odocoileus virginianus) for antibodies to bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) was tested with matched samples of serum and eluted dried whole blood. Results from matched serum virus neutralization (SN) tests indicated that a 1-ml elution from a 1- x 2-cm section of filter paper strip containing dried blood approximated a 1:10 serum dilution. Neutralizing antibody titers detected from 34 matched titrations of serum and dried blood samples were equivalent in 25 (74%) titrations and were within a single dilution in the remaining nine (26%) titrations. Eluted blood samples from SN-positive deer, however, did not produce detectable precipitin lines on agar gel immunodiffusion tests for antibodies to either BTV or EHDV. In a trial using serum and dried blood samples from 108 hunter-killed deer from five locations in Georgia (USA), antibody prevalence and serotype distribution results were similar. Use of dried blood samples for serologic testing for antibodies to BTV and EHDV provides a reliable alternative to serum but should be considered only when serum collection is not feasible.     

Seroepidemiology of chlamydial infections of wild ruminants in Spain

Chlamydial infections were determined serologically among wild ruminants in the Nature Park of the Sierras de Cazorla, Segura y Las Villas (CNP; Spain). Sampling was done during the period from 1990-95. There were 1,244 blood samples collected, consisting of 490 from fallow deer (Dama dama), 343 from mouflon (Ovis mussimon), 283 from red deer (Cervus elaphus) and 128 from Spanish ibex (Capra pyrenaica). Specific complement-fixing antibodies of Chlamydia spp. were detected by means of microtechnique, using lipopolysaccharide antigen. The relationship of biological (species, sex, age), temporal (year) and territorial (central and peripheral areas) factors to seropositive prevalence was examined, and preliminary data were collected on whether or not sheep and goat herds grazing in the peripheral areas of the park also were infected with Chlamydia spp. Chlamydiosis was common in the four species of wild ruminants in the CNP in all the years studied. The prevalence of Chlamydia sp. in mouflon (37%) was significantly greater than in fallow deer (30%), and both had a significantly higher prevalence rate than Spanish ibex and red deer (both 24%). The four species of wild ruminants were similar in that they act as reservoirs of Chlamydia spp., although their receptivity may be different, and the infection can certainly be maintained among these animals by intra-group transmission. The differences in prevalences and geometric mean titers (GMT), both between the sexes (male versus female) and between different ages (adult versus juvenile), were insignificant in all four species. For all species of wild ruminants both prevalence rates and GMTs were greater in populations occupying the peripheral areas of the park than in those inhabiting the central area. Herds of sheep and goats had a high prevalence of chlamydiosis. Intertransmission of Chlamydia sp. between wild and domestic ruminants occurred through grazing on the same pastures. The highest mean prevalence (44%) of patent infections (CFT titers of > or =1:80) was detected in red deer, although this frequency was not significantly different from those observed in mouflon (39%), Spanish ibex (38%), and fallow deer (37%). The proportion of patent infection was higher in females than in males, and none of the juveniles (<2-yr-old) showed patent infections. The prevalence of predicted patent chlamydial infections was always higher in the peripheral areas of the park, although only among mouflon and fallow deer were the differences statistically significant.     

Prevalence of antibody titers to Leptospira spp. in Minnesota white-tailed deer.

Serum samples (n = 204) from 124 white-tailed deer (Odocoileus virginianus) in northeastern Minnesota (USA) were collected from 1984 through 1989 and tested for antibodies to six serovars of Leptospira interrogans (bratislava, canicola, grippotyphosa, hardjo, icterohemorrhagiae, and pomona) using a microtiter agglutination test. Eighty-eight (43%) sera were positive at greater than or equal to 1:100 for antibodies against serovars pomona and/or bratislava; none was positive for any of the other four serovars. None of the 31 sera collected in 1984-85 was positive, whereas all 54 sera collected from 1986 through 1988 had titers of greater than or equal to 1:100. During 1989, only 34 (29%) of 119 sera had titers of greater than or equal to 1:100. Based on these results, we believe there to be wide variability in exposure of Minnesota deer to Leptospira interrogans.     

Long-Term Survival of Leptospira in a Biphasic Culture Medium Containing Charcoal

A comparison was made of the survival of 28 leptospiral serotypes in Fletcher semisolid medium and in the same medium containing a basal layer of Fletcher medium plus 0.7% of agar and 0.5% of activated animal charcoal. A year after culture, more motile leptospires were observed by microscope examination in the biphasic medium. Two years after culture, 4 serotypes grown in the biphasic medium and 11 in Fletcher medium did not show motile cells. Nineteen of the serotypes maintained in Fletcher medium and 25 in the biphasic medium for 2 years grew on subculture into Fletcher medium. Subcultures from the biphasic medium showed the characteristic leptospiral ring growth earlier during the incubation period.