| the life history and host specificity of hepatozoon clamatae (apicomplexa: adeleorina) and its-1 nucleotide sequence variation of hepatozoon species of frogs and mosquitoes from ontario. | the life cycle of an intraerythrocytic hemogregarine, hepatozoon clamatae, was studied in green frogs (rana clamitans melanota), bullfrogs (rana catesbeiana), northern leopard frogs (rana pipiens), and in the mosquito, culex territans. gametogenesis, fertilization, and sporogony occurred within cells of the malpighian tubules of laboratory-reared cx. territans that had fed on naturally infected frogs. mature oocysts containing hundreds of sporocysts were observed in mosquitoes 30 days postfeedin ... | 1998 | 9714212 |
| alkaline single-cell gel (comet) assay and genotoxicity monitoring using two species of tadpoles. | small bodies of water (e.g., creeks, ponds, and drainage ditches) have received very little attention in genotoxicity studies, yet these areas are important because they are often the first to be affected by industrial effluents, sewage contaminants, accidental spills, internal combustion engine emissions, landfill runoffs, and pesticide uses. to address this deficiency, we examined erythrocytes in two species of tadpoles, rana clamitans and bufo americanus, using the alkaline single-cell gel (s ... | 1996 | 8844992 |
| blood parasites of amphibians from algonquin park, ontario. | during a 5 wk period beginning may 25, 1983, 329 amphibians, which included specimens of rana catesbeiana shaw, rana clamitans latreille, rana septentrionalis baird, rana sylvatica leconte, hyla crucifer wied, bufo americanus holbrook, and plethodon cinereus green, from lake sasajewun, algonquin park, ontario, canada were examined for blood parasites. the prevalences of species of trypanosoma, haemogregarina, lankesterella, babesiasoma, and thrombocytozoons in these amphibians were determined. t ... | 1984 | 6492319 |
| potential endocrine disruption of sexual development in free ranging male northern leopard frogs (rana pipiens) and green frogs (rana clamitans) from areas of intensive row crop agriculture. | intensive row crop agriculture (irca) for corn and soybean production is predominant in eastern and central north america. irca relies heavily on pesticide and nutrient inputs to maximize production under conventional systems. in 2003-2005, we assessed the occurrence of a suite of potential endocrine effects in amphibians inhabiting farm ponds and agricultural drains in irca areas of southwestern ontario. effects were compared to amphibians from two agricultural reference sites as well as four n ... | 2008 | 18582957 |
| ultrastructural, biochemical and biophysical properties of an erythrocytic virus of frogs from ontario, canada. | frog erythrocytic virus (fev), one of the largest icosahedral viruses, is enveloped, measures up to 450 nm in diameter, and contains double stranded dna. the virus is found in the cytoplasm of erythrocytes of rana catesbeiana, rana septentrionalis, and rana clamitans from algonquin park, ontario (canada). acidophilic inclusions in infected erythrocytes stained with giemsa's stain correspond to viroplasms from which fev buds and forms aggregates of virus particles as seen in the electron microsco ... | 1989 | 2810549 |
| phylogenetic relationships among hepatozoon species from snakes, frogs and mosquitoes of ontario, canada, determined by its-1 nucleotide sequences and life-cycle, morphological and developmental characteristics. | the molecular biological characteristics of hepatozoon species infecting various species of snakes, frogs and mosquitoes were investigated by determining the nucleotide sequences of the first internal transcribed spacer region. a phylogenetic analysis was performed on seven isolates of hepatozoon infecting snakes, including hepatozoon sipedon and four morphologically similar but not identical forms, and two isolates of hepatozoon catesbianae infecting green frogs (rana clamitans melanota). this ... | 1999 | 10221630 |
| caged amphibian tadpoles and in situ genotoxicity monitoring of aquatic environments with the alkaline single cell gel electrophoresis (comet) assay. | in previous studies we demonstrated that indigenous amphibian tadpoles are suitable organisms for monitoring small bodies of water (e.g., creeks, ponds, and drainage ditches) using the alkaline single cell gel electrophoresis (scg) or 'comet' assay. this approach involves detection, under alkaline conditions, of cell dna fragments which on electrophoresis migrate from the nuclear core, resulting in a 'comet with tail' formation. however, although often plentiful, tadpoles are not present in all ... | 1998 | 9651536 |
| genotoxicity monitoring of small bodies of water using two species of tadpoles and the alkaline single cell gel (comet) assay. | to monitor genotoxicity in small bodies of water (e.g., creeks, ponds, and drainage ditches) we examined tadpole erythrocytes of two species: rana clamitans and rana pipiens,using the alkaline single cell gel dna electrophoresis (scg) or "comet" assay. this approach involves detection, under alkaline conditions, of cell dna fragments which on electrophoresis migrate from the nuclear core, resulting in a "comet with tail" formation. fifty-six samples, a total of 606 tadpoles, from 18 sites in sou ... | 1997 | 9212794 |
| effect of release herbicide on mortality, avoidance response, and growth of amphibian larvae in two forest wetlands. | effects of release herbicide (triclopyr butoxyethyl ester, [tbee]) on mortality, avoidance response, and growth of larval amphibians (rana clamitans, rana pipiens) were investigated using in situ enclosures deployed in two forest wetlands in northern ontario, canada. release was applied at nominal concentrations ranging from 0.26 to 7.68 mg tbee acid equivalents (ae)/l. no significant deleterious effects of this herbicide on larval growth were detected. however, concentration-dependent mortality ... | 2005 | 16268155 |
| chemical and biomonitoring to assess potential acute effects of vision herbicide on native amphibian larvae in forest wetlands. | in conjunction with operational forest herbicide spray programs in ontario, canada, chemical and biological monitoring studies were conducted in 51 different wetlands to quantify the probability and magnitude of contamination by a glyphosate herbicide formulation (vision). wetlands were classified as oversprayed, adjacent, or buffered in relation to the operational target spray blocks. results show that vegetated buffers significantly mitigated against exposure and thus potential for acute effec ... | 2004 | 15095878 |