Publications by authors named "Thomas R Platt"

Co-infections of mammalian hosts with intestinal helminths and bacterial pathogens are common, especially in areas with inadequate sanitation. Interactions between co-infecting species and host microbiota can cause significant changes in host immunity, disease severity, and pathogen transmission, requiring unique treatment for each case. A greater understanding of the influences of parasite-bacteria co-infections will improve diagnosis and therapeutic approaches to control infectious diseases.

View Article and Find Full Text PDF

Two new genera and species of freshwater turtle blood flukes (TBFs) are described herein based on specimens infecting the nephritic and mesenteric blood vessels of "matamatas" (a side-necked turtle, [Schneider, 1783] [Pleurodira: Chelidae]) from the Amazon River Basin, Peru. These taxa comprise the first-named species and the first-proposed genera of freshwater TBFs from the continent of South America. A new comparison of all TBF genera produced 6 morphologically diagnosed groups that are discussed in light of previous TBF classification schemes and a novel phylogenetic hypothesis based on the nuclear large subunit ribosomal DNA (28S).

View Article and Find Full Text PDF

We know little about the founders of our discipline apart from their scientific contributions and brief biographical sketches, most frequently in published obituaries. A number of years ago, Ralph Lichtenfels, then Director of the National Parasite Collection, sent me photocopies of letters between Henry Baldwin Ward, Horace W. Stunkard, George A.

View Article and Find Full Text PDF

The course of infection of Echinostoma caproni was followed in female ICR mice, a permissive laboratory host, from infection to natural termination. Twenty-one mice were infected with 20 metacercariae via oral intubation and housed 3 per cage. Three mice from a randomly selected cage were necropsied at 1 mo intervals.

View Article and Find Full Text PDF

Griphobilharzia amoena Platt and Blair, 1991 was originally described as a dioecious trematode, parasitic in the circulatory system of the Australian freshwater crocodile, Crocodylus johnstoni, with the female completely enclosed in a gynecophoric chamber of the male and the 2 worms oriented anti-parallel to each other. A recent publication questions the original description, arguing that G. amoena is monoecious and, as a consequence, the species was transferred to Vasotrema Stunkard, 1928 (Spirorchiidae) as Vasotrema amoena n.

View Article and Find Full Text PDF

The migratory response of Echinostoma caproni to host feeding was examined in female ICR mice. Thirty-six mice were each infected with 20 metacercariae of E. caproni .

View Article and Find Full Text PDF

Circadian egg production by Echinostoma caproni was investigated in ICR mice. Four female mice were infected with 25 E. caproni metacercariae, maintained in individual cages on a 12:12 light:dark cycle, and provided food and water ad libitum.

View Article and Find Full Text PDF

Opisthioglyphe sharmai n. sp. is described from the gall bladder of the Malayan box turtle, Cuora amboinensis, and the black marsh turtle, Siebenrockiella crassicollis, in Malaysia.

View Article and Find Full Text PDF

Twenty-four female ICR mice, 12 acclimated to a 12 ∶ 12 light-dark cycle and 12 to a 12 ∶ 12 dark-light cycle for 7 days, were each infected with 10 metacercariae of Echinostoma caproni. Infected mice were maintained on their respective lighting regimes for 28 days. Six mice (3 from each group) were necropsied at 4-hr intervals beginning at 0700 hr.

View Article and Find Full Text PDF

The current experiments were designed to assess the interaction of light and gravity on the transmission of Echinostoma caproni cercariae to the second intermediate host, Biomphalaria glabrata. Transmission chambers were constructed of clear polyvinyl chloride pipe covered with a black sleeve to exclude light. Snails were constrained within the chamber to prevent movement, while permitting the cercariae to swim freely.

View Article and Find Full Text PDF

Patterns of infracommunity similarity were examined for 27 male and 6 female common snapping turtles, Chelydra serpentina serpentina, collected from Westhampton Lake on the campus of the University of Richmond in Richmond, Virginia, during the summer months of 1979 and 1980. Patterns of infracommunity similarity based on parasite abundance emphasized differences between years and between host sexes. Patterns of similarity based on parasite presence or absence emphasized differences among the months sampled.

View Article and Find Full Text PDF

We describe 2 new species of Camallanus (Nematoda: Camallanidae) from freshwater turtles collected in Queensland, Australia: Camallanus nithoggi n. sp. from Elseya latisternum (Gray) and Camallanus waelhreow n.

View Article and Find Full Text PDF

Trematode cercariae inhabit predictable environments and respond to trigger cues with genetically fixed releaser responses when foraging for the upstream host. The effect of light and gravity on the transmission of Echinostoma caproni cercariae to Biomphalaria glabrata was investigated experimentally. Transmission chambers were constructed of clear polyvinyl chloride pipe.

View Article and Find Full Text PDF

Patterns of infracommunity structure and infra- and component community similarity were examined for helminths of 6 species of turtles, each collected from a single locality in Australia in 1993 and 1994. Elseya latisternum (N = 11) and Emydura kreffti (N = 16) were collected from northern Queensland, Emydura macquarii macquarii (N = 11) from southern Queensland, Emydura macquarii dhara (N = 11) and Chelodina longicollis (N = 11) from northern New South Wales, and Chelodina oblonga (N = 5) from Western Australia. Local parasite species richness was not correlated with host geographical range.

View Article and Find Full Text PDF

Population density, or crowding, was examined to determine its effect on the morphometric variability of Echinostoma caproni (Digenea) in ICR mice. Six mice were infected with 25 and 100 metacercariae, and a single mouse was infected with 300 metacercariae. All mice were infected at necropsy 22 days postinfection with recoveries of 77%, 69%, and 7.

View Article and Find Full Text PDF

Examination of the type-specimen of Aptorchis aequalis Nicoll, 1914 (Digenea: Plagiorchiidae) revealed anatomical features not included in the original description; most notably the intestinal caeca extend to near the posterior end of the worm instead of terminating just posterior to the ventral sucker. A comparison of the type of A. aequalis with specimens identified as Dingularis anfracticirrus Jue Sue & Platt, 1999, from the author's collection yielded no differences that would justify the recognition of two genera.

View Article and Find Full Text PDF