Microlichus americanus acariasis in saffron finches (Sicalis flaveola) with dermatitis and feather loss.

Over a 5-year period, 13 saffron finches (Sicalis flaveola) housed in mixed aviaries at the Bronx Zoo (Bronx, New York) were examined with feather loss and dermatitis, primarily affecting the nape, neck, and dorsum. Feather loss, hyperkeratosis, epidermal hyperplasia, and mixed granulocytic and mononuclear inflammation were identified in biopsies from live birds and tissue sections from postmortem specimens. In 10 of 13 cases, sections of arthropod parasites were seen histologically within feather follicles and along the surface of affected skin. Based on morphological characteristics, mites recovered from samples of formalin-fixed skin in 4 birds were identified as Microlichus americanus, an epidermoptid mite infrequently reported from wild birds and hippoboscid flies. Gross and histological lesions strongly implicate M. americanus as the cause of dermatitis affecting practically all saffron finches in the collection.

Gastrointestinal Parasites of Ecuadorian Mantled Howler Monkeys (Alouatta palliata aequatorialis) Based on Fecal Analysis.

An analysis of gastrointestinal parasites of Ecuadorian mantled howler monkeys, Alouatta palliata aequatorialis, was conducted based on examination of fecal smears, flotations, and sedimentations. At least 1 type of parasite was detected in 97% of the 96 fecal samples screened across 19 howler monkey groups using these techniques. Samples averaged 3.6 parasite species per individual (±1.4 SD). Parasites included species representing genera of 2 apicomplexans: Cyclospora sp. (18% of individual samples) and Isospora sp. (3%); 6 other protozoa: Balantidium sp. (9%), Blastocystis sp. (60%), Chilomastix sp. (4%), Dientamoeba sp. (3%), Entamoeba species (56%), Iodamoeba sp. (5%); 4 nematodes: Enterobius sp. (3%), Capillaria sp. (78%), Strongyloides spp. (88%) which included 2 morphotypes, Trypanoxyuris sp. (12%); and the platyhelminth Controrchis sp. (15%). A statistically significant positive correlation was found between group size and each of 3 different estimators of parasite species richness adjusted for sampling effort (ICE: r(2) = 0.24, P = 0.05; Chao2: r(2) = 0.25, P = 0.05, and Jackknife: r(2) = 0.31, P = 0.03). Two significant associations between co-infecting parasites were identified. Based on the prevalence data, individuals infected with Balantidium sp. were more likely to also be infected with Isospora sp. (χ(2) = 6.02, P = 0.01), while individuals harboring Chilomastix sp. were less likely to have Capillaria sp. present (χ(2) = 4.03, P = 0.04).

Characterization of Giardia duodenalis infections in dogs in Trinidad and Tobago.

To our knowledge, the zoonotic potential of Giardia duodenalis has not been assessed in companion animals in Trinidad and Tobago. This report details the first attempt to evaluate the potential zoonotic risk of G. duodenalis in dogs and identify assemblages of G. duodenalis found in dog populations on both islands. Fecal samples were collected from free-roaming dogs and dogs at the Trinidad and Tobago Society for the Prevention of Cruelty to Animals from October 2010 to June 2011. A total of 168 samples were collected of which 104 samples were analyzed for the presence of G. duodenalis by PCR amplification of the ssu-rRNA gene with subsequent assemblage-typing. A subset of samples was also analyzed by ELISA. Twenty-six samples were positive for G. duodenalis by PCR for an overall prevalence of 25%. Four samples were identified as assemblage C (15.4%), 21 as assemblage D (80.8%), and one as assemblage E (3.8%). Puppies were four-times more likely to be infected with G. duodenalis than adult dogs (OR 4.61, 95% CI 1.73-12.2). There was a significant agreement between ELISA and PCR in the detection of the protozoa (κ=0.67). We infer from our results that while the prevalence of G. duodenalis is relatively high in Trinidad and Tobago, the zoonotic risk of infection in humans is low since neither assemblage A nor B was identified in the study population.

Prevalence of antibodies to Toxoplasma gondii in white-tailed deer (Odocoileus virginianus) in New York State, USA.

Sera collected from 299 white-tailed deer (Odocoileus virginianus) harvested in New York State by hunters in November 2010 were assayed for anti-Toxoplasma gondii IgG antibodies. White-tailed deer are a useful sentinel for risk of human and domestic animal exposure to Toxoplasma oocysts and pose a potential risk for infection to humans and other animals by ingestion of the meat. White-tailed deer share grazing space with domestic animals raised for meat and are likely to be exposed by horizontal transmission through oocyst consumption, similar to other grazing species of economic concern. Overall, 42.2% of samples were positive by enzyme-linked immunosorbent assay, indicating a true prevalence of 38.5%, with a significantly higher proportion of adult than immature deer antibody positive. No significant difference in prevalence was found between male and female deer nor was there a significant effect of local human population density on deer antibody prevalence. These results provide insight into the risk of environmental Toxoplasma exposure in New York State and support horizontal transmission through oocyst consumption as the most common mechanism of white-tailed deer infection.

Free-ranging black howler monkeys, Alouatta pigra, in southern Belize are not parasitized by Controrchis biliophilus.

Several coprological studies of Alouatta pigra, the black howler monkey, inhabiting Belize and Mexico have been published in the past several years. Trematodes, specifically Controrchis biliophilus (Dicrocoeliidae), have been detected in A. pigra from all locations in Belize and Mexico examined in those studies. A routine coprological survey of A. pigra was conducted in May and June 2010 as part of baseline data collection for an A. pigra population in Punta Gorda, Toledo District, southern Belize. The 51 fecal samples collected in this area were all negative for C. biliophilus. Subsequently, two additional fecal samples were collected from another population of A. pigra in Toledo District and 25 additional fecal samples were collected from six other areas of Belize during December 2010 and January 2011 and were examined for parasites. To date, C. biliophilus eggs have been detected in fecal samples from A. pigra inhabiting every district of Belize except Toledo District in southern Belize. This finding is notable, for no other population of A. pigra completely free of C. biliophilus infection had been located prior to this study.

Investigation of an outbreak of besnoitiosis in donkeys in northeastern Pennsylvania.

OBJECTIVE: To describe the clinical, endoscopic, and serologic features of an outbreak of besnoitiosis in 2 donkey operations in northeastern Pennsylvania and to report the outcome of attempted treatment of 1 naturally infected individual. DESIGN: Observational study. ANIMALS: 29 donkeys (Equus asinus) in northeastern Pennsylvania. PROCEDURES: Donkeys were examined for lesions suggestive of besnoitiosis in an outbreak investigation. Information was collected regarding the history and signalment of animals on each premises. Rhinolaryngoscopy was performed to identify nasopharyngeal and laryngeal lesions. Serum samples were collected for immunofluorescent antibody testing and immunoblotting for Besnoitia spp. Skin biopsy samples were obtained from 8 animals with lesions suggestive of besnoitiosis for histologic examination. Quantitative real-time PCR assay for Besnoitia spp was performed on tissue samples from 5 animals. RESULTS: Besnoitiosis was confirmed in 6 of the 8 suspected cases. The most common lesion site was the nares, followed by the skin and sclera. Donkeys with clinical signs of disease had higher serum antibody titers and tested positive for a greater number of immunoblot bands than did donkeys without clinical signs of disease. All animals evaluated by PCR assay tested positive. Putative risk factors for disease included age and sex. Ponazuril was not effective at treating besnoitiosis in a naturally infected donkey. CONCLUSIONS AND CLINICAL RELEVANCE: Knowledge of clinical and serologic features of besnoitiosis in donkeys will assist clinicians in the diagnosis and prevention of this disease in donkey populations. Besnoitiosis may be an emerging disease of donkeys in the United States.

Chimeric protein A/G conjugate for detection of anti-Toxoplasma gondii immunoglobulin G in multiple animal species.

Serological testing for toxoplasmosis diagnosis remains the method of choice in human medicine due to the accessibility of the requisite sample, the difficulty in predicting the parasite's location in the host for direct detection, and the availability of established commercial methods. In veterinary medicine, although the first 2 conditions are unchanged, there is a need for commercially produced test methods that are validated for Toxoplasma gondii detection across the range of animal species that can serve as intermediate hosts. The development of such a serological method for animals would allow the diagnosis of toxoplasmosis in individual animals and a higher throughput method for population-level toxoplasmosis surveys. The incorporation of a non-species-specific chimeric protein A/G conjugate into an anti-Toxoplasma immunoglobulin G enzyme-linked immunosorbent assay is described. Serum from potential intermediate hosts was reevaluated using this method and compared with earlier testing using an established agglutination procedure. Very good agreement between the 2 tests was noted (κ = 0.81), establishing the method as a useful option for veterinary diagnostic testing.

Evaluation of factors associated with the risk of infection with Cryptosporidium parvum in dairy calves.

OBJECTIVE: To identify risk factors associated with Cryptosporidium parvum infection in dairy calves. ANIMALS: 108 case animals and 283 control animals. PROCEDURES: Case animals were calves infected with C. parvum, and controls were infected with Cryptosporidium bovis (n = 67) or calves not infected with Cryptosporidium spp. Fecal samples were tested via the flotation concentration method for Cryptosporidium spp. Samples were genotyped by sequencing of the 18s rRNA gene. Associations between host, management, geographic, and meteorologic factors and Cryptosporidium genotype were assessed. RESULTS: Younger calves and calves housed in a cow barn were more likely to be infected with both genotypes. Herd size and hay bedding were associated with an increased risk of infection with C. parvum, and Jersey breed was a risk factor for C. bovis infection. Compared with a flat surface, a steeper slope was significantly associated with a decreased likelihood of infection with both genotypes, and precipitation influenced the risk of C. parvum infection only. CONCLUSIONS AND CLINICAL RELEVANCE: Risk factors for calf infection with C. parvum differed from those for infection with C. bovis. Results may be useful to help design measures that reduce animal exposure and decrease public health risk and economic losses associated with C. parvum infection in cattle.

Prevalence of Giardia duodenalis assemblages among dairy herds in the New York City Watershed.

A longitudinal herd-level study was carried out to determine the cumulative incidence of Giardia duodenalis infections in dairy cattle in the New York City Watershed. We also sought to assess the changes in infection pattern of animals diagnosed as shedding Giardia over time, determine risk factors that may be associated with G. duodenalis infections, and identify potentially zoonotic infections. A total of 2109 fecal samples were randomly collected from dairy cattle at 34 farms in the New York City Watershed on a seasonal basis. A total of 504 Giardia-positive samples were identified by zinc sulfate flotation. The overall cumulative incidence of G. duodenalis based on flotation results was 23.9% with 73.8% of all infections occurring in animals under 180 days of age (372/504). The intensity of infection ranged from 2 to 563,200 cysts/gram of feces. Cattle shedding Cryptosporidium spp. oocysts were twice as likely to shed G. duodenalis cysts in comparison to the animals that did not shed oocysts (1.81 95% CI 1.26-2.60 p=0.0012). In the multivariate analysis, only the age of the animal and the presence of dogs on the farm were significantly associated with the likelihood of shedding G. duodenalis. DNA was extracted from positive samples and analyzed by polymerase chain reaction (PCR) of the beta-giardin and triosephosphate isomerase genes of Giardia spp. 304 samples were analyzed by PCR of which 131 were sequenced. 22.1% of sequenced samples were identified as assemblage A and 77.9% were identified as assemblage E. Interestingly, 100% of specimens identified as assemblage A were from calves under 84 days of age indicating that younger cattle are important reservoirs for potentially zoonotic assemblages of G. duodenalis.

Modification of a commercial Toxoplasma gondii immunoglobulin G enzyme-linked immunosorbent assay for use in multiple animal species.

A challenge faced by veterinary diagnosticians in serologic analysis for exposure to pathogens is the need for a protein conjugate capable of antibody attachment in many animal species. The advent of protein conjugates that are less specific in nature allows diagnosis across many species with little or no modification of technique. Toxoplasma gondii is an organism of veterinary interest that has been demonstrated to infect a plethora of warm-blooded animals. However, the serologic tests available for simultaneous diagnosis in this broad range are limited in number. The current study examined the use of an immunoglobulin G enzyme-linked immunosorbent assay (ELISA) modified by the use of non-species-specific protein conjugates in domestic animal species commonly submitted to diagnostic laboratories for evaluation of Toxoplasma exposure status. Comparison with results from an established indirect hemagglutination technique revealed very good agreement between the 2 test methods. This modification of the ELISA provides a useful method for veterinary diagnosticians to perform rapid and accurate evaluation of multiple animal species for Toxoplasma exposure using a single test.

Temporal and spatial dynamics of Cryptosporidium parvum infection on dairy farms in the New York City Watershed: a cluster analysis based on crude and Bayesian risk estimates.

BACKGROUND: Cryptosporidium parvum is one of the most important biological contaminants in drinking water that produces life threatening infection in people with compromised immune systems. Dairy calves are thought to be the primary source of C. parvum contamination in watersheds. Understanding the spatial and temporal variation in the risk of C. parvum infection in dairy cattle is essential for designing cost-effective watershed management strategies to protect drinking water sources. Crude and Bayesian seasonal risk estimates for Cryptosporidium in dairy calves were used to investigate the spatio-temporal dynamics of C. parvum infection on dairy farms in the New York City watershed. RESULTS: Both global (Global Moran's I) and specific (SaTScan) cluster analysis methods revealed a significant (p < 0.05) elliptical spatial cluster in the winter with a relative risk of 5.8, but not in other seasons. There was a two-fold increase in the risk of C. parvum infection in all herds in the summer (p = 0.002), compared to the rest of the year. Bayesian estimates did not show significant spatial autocorrelation in any season. CONCLUSIONS: Although we were not able to identify seasonal clusters using Bayesian approach, crude estimates highlighted both temporal and spatial clusters of C. parvum infection in dairy herds in a major watershed. We recommend that further studies focus on the factors that may lead to the presence of C. parvum clusters within the watershed, so that monitoring and prevention practices such as stream monitoring, riparian buffers, fencing and manure management can be prioritized and improved, to protect drinking water supplies and public health.

Incidence of and risks associated with Giardia infections in herds on dairy farms in the New York City Watershed.

BACKGROUND: The primary aims of this study were to determine the incidence of Giardia infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of Giardia and Cryptosporidium spp. are common in this population, we also evaluated the effect of herd infection status on Giardia infections. METHODS: Farms were grouped into three cohorts based on their prior infection status with Giardia and/or Cryptosporidium spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of Giardia cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding. RESULTS: The majority of Giardia infections occurred in calves within their first 180 days of age, with the most number of calves shedding Giardia cysts between 11 and 20 days of age. The incidence of shedding of Giardia cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding Giardia cysts varied significantly with the age (p<0.0001) and the season of collection (p=0.0151 for Spring). CONCLUSION: Giardia infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based on changes in management practices corresponding to weather patterns of a particular season. A dairy herd's prior infection status with Cryptosporidium influences the likelihood of infection with Giardia.

Seasonal variation in the prevalence and molecular epidemiology of Cryptosporidium infection in dairy cattle in the New York City Watershed.

We conducted cross-sectional studies in the New York City Watershed to ensure a valid estimate of the risk associated with Cryptosporidium infection in dairy herds. Our aims were to obtain species-specific estimates of the prevalence of Cryptosporidium in dairy cattle and to investigate seasonal variations in prevalence. We validated our empirical estimates using a Bayesian approach. Samples were collected on 32 study farms, once in each of 3 different seasons using an age-stratified sampling design. The overall prevalence of Cryptosporidium parvum-like species and Cryptosporidium andersoni among the 1911 animals tested by the flotation method was 5% and 1%, respectively. Among preweaned calves (<65 days of age), the prevalence of C. parvum-like species was twice as high in the summer (26%) compared with the winter (11%). Herd prevalence showed the same seasonal trend. Preweaned calves were also shedding C. andersoni at an average intensity of 20 oocysts per gram of feces. We did not detect C. parvum-like oocysts in cattle older than 5 months. Sequencing of a portion of the 18s rRNA gene revealed that in the summer, 42% of the C. parvum-like oocysts shed by preweaned calves were zoonotic, compared with >74% during the rest of the year. Both empirical and stochastic methods revealed a summer peak in the prevalence of C. parvum-like oocysts in preweaned calves. Determining whether seasonal variation in the prevalence and proportion of Cryptosporidium species shed by preweaned calves is due to management practices or ecological factors will have important implications for effective control of this parasite.

Factors associated with the risk of Giardia species infection in two sympatric species of Peromyscus mice.

An epidemiologic case-control study was conducted to identify factors that predispose Peromyscus spp. to the risk of infection with Giardia sp. in watersheds. A total of 200 Giardia sp.-positive mice (cases) and a similar number of Giardia sp.-negative mice (controls) were selected from a population 2,528 mice captured in a watershed in southeastern New York State. The Giardia sp. infection status of the mice was determined by centrifugation concentration flotation and an enzyme-linked immunosorbent assay. The mice were later classified into 2 species, Peromyscus maniculatus and P. leucopus, using cellulose acetate electrophoresis of individual saliva samples. The risk of infection was evaluated while controlling for indigenous factors (age and sex) and exogenous factors (habitat and land use) that were hypothesized to influence the likelihood of infection with Giardia sp. The study population consisted of 257 (59%) P. leucopus and 165 (41%) P. maniculatus. Peromyscus leucopus mice were at a higher risk of becoming infected with Giardia in comparison to P. maniculatus (adjusted odds ratio = 40). The risk of Giardia sp. infection varied with the age of the animals, since adult animals were at higher risk than juvenile animals. This study suggested a difference in susceptibility to Giardia sp. between different species of mice.

A survey of parasites identified in the feces of eastern spotted skunks (Spilogale putorius) in western Arkansas.

The endoparasite community of the eastern spotted skunk (Spilogale putorius) is poorly known. We surveyed parasites found in the feces of 29 eastern spotted skunks captured between March 2005 and January 2007 from a population in west-central Arkansas as part of a broader study of the ecology of the species. We identified 13 species (nine nematodes, four protozoa) from 82 fecal samples. Mean (+/-SD) number of species per individual skunk was 4.1+/-2.1, although this is likely an underestimate because some individuals were sampled more intensively than others. Most of the identified parasite species were also found in other skunk species or in other small carnivore species.

Eurytrema procyonis and pancreatitis in a cat.

A young adult male domestic shorthair cat was presented for physical examination, routine vaccinations, and a fecal examination. Physical examination revealed no significant abnormalities. Eggs of the raccoon pancreatic fluke Eurytrema procyonis were detected by fecal flotation. Results of a complete blood count and serum biochemistry panel were normal. Abdominal sonography revealed an enlarged hypoechoic pancreas with a hyperechoic rim, and a distended and thickened pancreatic duct. Serum pancreatic lipase immunoreactivity (PLI) was increased. These findings supported the possibility of fluke-associated pancreatitis. Treatment with praziquantel/pyrantel/febantel was associated with resolution of sonographic abnormalities and normalization of PLI.

Cryptosporidium spp. from small mammals in the New York City watershed.

The objective of this study was to assess the potential role that wildlife plays in environmental degradation of watersheds through the contamination of the water supply with zoonotic genotypes of Cryptosporidium. Cryptosporidium isolates recovered from wildlife in the New York City (NYC) watershed were examined to determine genotype using a polymerase chain reaction protocol targeting the 18-Small Subunit (SSU) rRNA locus. Seventy-seven DNA samples recovered from 12 wildlife host species captured in the NYC watershed were amplified and sequenced. Data on risk factors associated with the perpetuation of these genotypes also were collected and analyzed. Although many genotypes appeared to be host-specific, 38% of the samples examined were identified as Cryptosporidium parvum, indicating the presence of zoonotic Cryptosporidium. Adult animals were more likely to shed the zoonotic strains of Cryptosporidium spp. Animals captured in the fall and winter were more likely to be infected with C. parvum than those captured in spring and summer.

Evaluation of polymerase chain reaction diagnosis of Cryptosporidium spp in dairy cattle and wildlife.

This study investigated the utility of the polymerase chain reaction (PCR) protocol as a screening test for Cryptosporidium spp in 125 fecal samples from dairy cattle and wild rodents. Samples initially examined by fecal flotation and ELISA were evaluated using four PCR protocols (18S SSU rRNA, TRAP-C2, HSP70, and COWP), and the relative accuracy and agreement of PCR protocols was assessed. Although PCR can be both highly sensitive and accurate, the ability of these protocols to accurately detect DNA in samples can vary. A combination of techniques may be the best choice for to screen samples for this parasite.

Prevalence of Cryptosporidium species in wildlife populations within a watershed landscape in southeastern New York State.

A cross-sectional study was conducted to determine the prevalence of Cryptosporidium in wildlife in the New York City (NYC) Watershed in southeastern New York State. A total of 6227 fecal samples were collected and evaluated from 5892 mammals (38 species), 263 birds (14 species), 2 reptiles (2 species), 8 amphibians (4 species), and 62 fish (15 species). Cryptosporidium was detected in 30 species. Of the species found positive for Cryptosporidium, 16 represented new records for this parasite-Alosa pseudoharengus, Larus delawarensis, Blarina brevicauda, Sorex cinereus, Parascalops breweri, Myotis lucifugus, Peromyscus maniculatus, Microtus pennsylvanicus, Clethrionomys gapperi, Tamiasciurus hudsonicus, Marmota monax, Erethizon dorsatum, Canis latrans, Mustela erminea, Mustela vison, and Lynx rufus. Factors such as age, sex, season, and land use were evaluated to determine if there was any association with infection by this parasite. Animals were more likely to be positive for Cryptosporidium during spring and in agricultural land use.

Factors associated with shedding of Cryptosporidium parvum versus Cryptosporidium bovis among dairy cattle in New York State.

OBJECTIVE: To isolate and speciate Cryptosporidium DNA from fecal samples obtained from dairy cattle in New York State and identify factors associated with whether cattle were shedding Cryptosporidium parvum versus Cryptosporidium bovis. DESIGN: Cross-sectional study. SAMPLE POPULATION: 115 fecal samples positive for DNA coding for the Cryptosporidium 18S rRNA gene from dairy cattle in New York State. PROCEDURES: A PCR assay was used to amplify DNA from fecal samples; amplification products were submitted for bidirectional DNA sequencing. Logistic regression was used to test for associations between various host factors and Cryptosporidium spp. RESULTS: 70 of the 115 (61%) fecal samples were found to have C parvum DNA, 42 (37%) were determined to have C bovis DNA, and 3 (3%) were found to have C parvum deer-type DNA. The presence of diarrhea at the time of fecal sample collection, oocyst count, and breed were associated with whether cattle were infected with C parvum or C bovis, with animals more likely to be infected with C parvum if they had diarrhea, had a high oocyst count, or were Holsteins. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that C parvum and C bovis can be isolated from dairy cattle in New York State and that various factors affect whether cattle infected with Cryptosporidium spp are infected with C parvum or C bovis. Findings also lend credence to the theory that C bovis may be more host adapted and thus less pathogenic to dairy cattle than C parvum.