Surviving predation is a fitness trait of Escherichia coli O157:H7 (EcO157) that provides ample time for the pathogen to be transported from reservoirs (e.g. dairies and feedlots) to farm produce grown in proximity. Ionophore dietary supplements that inhibit rumen protozoa may provide such a selective advantage for EcO157 to proliferate in lagoons as the pathogen is released along with the undi...

The mitotic, micronuclear division of the heterotrichous genus Blepharisma has been studied by electron microscopy. Dividing ciliates were selected from clone-derived mass cultures and fixed for electron microscopy by exposure to the vapor of 2% osmium tetroxide; individual Blepharisma were encapsulated and sectioned. Distinctive features of the mitosis are the presence of an intact nuclear env...

Five acidophilic protozoa (three flagellates, one ciliate and one amoeba) were isolated from acid mine water and a coal biotreatment plant, and grown in mixed cultures with acidophilic bacteria. Cultures were routinely maintained in ferrous sulphate media: in media containing pyrite or pyritic coal, protozoa grew in cultures containing coarse-grain (61-200 pm) but not fine-grain (c 61 pm) miner...

Balch, C. C., Johnson, V. W. & Turner, I. A. (1955). Rep. Nut. Inst. Dairy. Reading, p . 40. Balch, D. A. & Rowland, S. J. (1957). Biit.J. Nutr. XI, 288. Barry, J. M. (1958). Proc. roy. Soc. B, 149, 380. Burt, A. W. A. (1957). Dairy Sci. Abstr. 19, 436. Folley, S. J. (1956). The Physiology and Biochemistry of Lactation. Edinburgh and London: Oliver and Boyd. Glascock, R. F. (1958). Proc. roy. S...

Six rumen-fistulated and defaunated wethers were fed twice daily a pelleted diet of barley and dehydrated lucern at a rate of 50 g dry matter/kg body weight °-!5. Two months later, the sheep were divided into three equal groups. Each group was then inoculated in the rumen with one of the following three genera of protozoa : Polyplastron multivesiculatum (P), Entodinium sp. (E), or lsotricha pro...

The membrane response to mechanical stimulation was investigated under voltage-clamp conditions in the hypotrich ciliate Stylonychia mytilus (Protozoa). The mechanoreceptor current shows high ionic selectivity, unlike than in metazoans. It is exclusively carried by potassium ions and is selectively inhibited by tetraethylammonium and 4-aminopyridine. Procaine, tetramethylammonium, caesium and d...

Small ciliate protozoa of the genus Uronema were separated from labeled bacteria by means of a discontinuous sucrose gradient. More than 98% of the radioactivity associated with the bacteria was found in the upper portion of the gradient, whereas the remaining portion of the gradient contained the ciliates.