title: Prevalence of Toxoplasma gondii infections in Pennsylvania black bears, Ursus americanus.
abstract: Serum samples from 665 hunter-killed black bears killed in 1989 to 1992 throughout Pennsylvania (USA) were tested for Toxoplasma gondii antibodies by the agglutination test in dilutions of 1:25, 1:50, and 1:500. Toxoplasma gondii antibodies were found in 535 of 665 (80%) bears. Considering the highest dilutions at which antibodies were detected, prevalences were 10% at 1:25, 37% at 1:50 and 33% at 1:500. No significant difference in antibody prevalence was found between males (79%) and females (80%), but a significant difference was found between juvenile (65%) and adult (83%) bears.
authors.affiliation: Department of Biology, Indiana University of Pennsylvania 15701.
authors.forename: N
authors.initials: N
authors.lastname: Briscoe
authors.forename: J G
authors.initials: JG
authors.lastname: Humphreys
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
mesh_terms: D000367:Age Factors; D000372:Agglutination Tests; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D016009:Chi-Square Distribution; D005260:Female; D008297:Male; D010414:Pennsylvania / Q000453:epidemiology; D015995:Prevalence; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000453:epidemiology*; D001503:Ursidae / Q000469:parasitology*
chemical_list: D000913:Antibodies, Protozoan