Browsing by Author "Hill, Dolores E."

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    Detection of Hammondia heydorni-like organisms and their differentiation from Neospora caninum using random-amplified polymorphic DNA-polymerase chain reaction
    Sreekumar, C.; Hill, Dolores E.; Fournet, V. M.; Rosenthal, B. M.; Lindsay, David S.; Dubey, Jitender P. (American Society of Parasitology, 2003-10)
    Neospora caninum and Hammondia heydorni are morphologically and phylogenetically related coccidians that are found in dogs. New diagnostic genetic loci, based on random-amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) were developed to aid in the detection of H. heydorni like parasites and to discriminate them from N. caninum and other related coccidians of dogs. On the basis of the data obtained from 5 random decamers, H. heydorni (Manhattan-1) and N. caninum (NC1) were characterized by distinct banding patterns (similarity index = 0.068). High-stringency PCR assays were developed from the sequences of 2 cloned hands (GenBank BZ592549 and BZ592593), uniquely amplified from H. heydorni. Interestingly, using these primers, PCR amplification was achieved only from 2 of the 5 isolates presumed to represent H. heydorni. The same result was obtained From these 5 isolates using a recently described PCR assay directed to the H. heydorni internal transcribed spacer-1. It is concluded that H. heydorni and N. caninum are genetically distinct and that such tools may be useful for more detailed characterization of the diversity of related parasites occurring in dogs.
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    Hepatitis E Virus in Pigs from Slaughterhouses, United States, 2017-2019
    Sooryanarain, Harini; Heffron, C. Lynn; Hill, Dolores E.; Fredericks, Jorrell; Rosenthal, Benjamin M.; Werre, Stephen R.; Opriessnig, Tanja; Meng, Xiang-Jin (2020-02)
    Hepatitis E virus (HEV) RNA was detected in 6.3% and HEV IgG in 40% of 5,033 serum samples from market-weight pigs at 25 slaughterhouses in 10 US states. The prevalent HEV genotype was zoonotic genotype 3, group 2. Blood of HEV-viremic pigs from slaughterhouses may contaminate pork supply chains.
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    Molecular and biological characterization of Hammondia heydori-like oocysts from a dog fed hearts from naturally infected white-tailed deer (Odocoileus virginianus)
    Dubey, Jitender P.; Sreekumar, C.; Miska, K. B.; Hill, Dolores E.; Vianna, M. C. B.; Lindsay, David S. (American Society of Parasitology, 2004-10)
    Neospora caninum and Hammnondia heydorni are morphologically and phylogenetically related coccidians that are found in dogs. Although there is serological evidence of N. caninum infection in the white-tailed deer (Odocoileus virginianus), the parasite has not been yet isolated from the tissues of this host. In an attempt to isolate N. caninum from deer, hearts from 4 deer with antibodies to N. caninum were fed to 2 dogs. One of these dogs shed unsporulated oocysts 12-14 mum in diameter. Sporulated oocysts were not infective to Mongolian gerbils (Meriones ungulatus), and DNA isolated from these oocysts was not amplified using N. caninum-specific primers. However, positive amplification with the H. heydorni-specific first internal transcribed spacer (ITS-1) primers and common toxoplasmatiid ITS-1 primers confirmed the presence of H. heydorni DNA in the samples. The oocysts were considered to be H. heydorni on the basis of their morphology, biology, and molecular characteristics. This is the first record of a H. heydornilike parasite in the white-tailed deer.