Sarcocystis cruzi infection in wood bison (Bison bison athabascae).

Endangered wood bison (Bison bison athabascae) is the largest terrestrial mammal in the American continent. Animal health is an important issue in their conservation, and Sarcocystis cruzi may be a cause of clinical disease in Bovidae. Hearts of eight wood bison from Alaska, USA were examined for sarcocysts by histology, transmission electron microscopy, pepsin digestion, and molecularly.

Phylogenetic analysis of Sarcocystis nesbitti (Coccidia: Sarcocystidae) suggests a snake as its probable definitive host.

Sarcocystis nesbitti was first described by Mandour in 1969 from rhesus monkey muscle. Its definitive host remains unknown. 18S rRNA gene of S.

Sarcocystis cruzi: comparative studies confirm natural infections of buffaloes.

Controversy exists concerning whether cattle and water buffalo sustain infections with cysts of distinct arrays of species in the genus Sarcocystis. In particular, morphologically similar parasites have been alternately ascribed to Sarcocystis cruzi or to Sarcocystis levinei, depending on their occurrence in cattle or water buffalo. We used light and transmission electron microscopy, genetic analysis, and experimental infections of definitive canine hosts to determine whether consistent differences could be identified from parasites derived from several natural infections of each host, examining several tissue types (esophagus, skeletal muscles, and heart).

Detection of sarcocystis parasites in retail beef: a regional survey combining histological and genetic detection methods.

Sarcocystis spp. are parasitic protists acquired when undercooked, cyst-laden meat is consumed. While both Sarcocystis hominis and S.

Human dispersal of Trichinella spiralis in domesticated pigs.

To investigate the human impact on the evolutionary ecology of animal pathogens, we compared genetic diversity of severe foodborne parasites contracted by eating infected pork or wild game. In particular, we characterized Trichinella spp. from twenty-eight countries and four continents by genotyping nine microsatellite loci and sequencing one-fifth of the mitochondrial genome.

Restricted genetic diversity in the ubiquitous cattle parasite, Sarcocystis cruzi.

Although parasites of the genus Sarcocystis have likely cycled between bovine herbivores and canine carnivores for tens of millions of years, humans may have profoundly influenced the ecology and evolution of those prevalent in domesticated dogs and cattle. To preliminarily assess the possibility of such anthropogenic effects, we surveyed genetic variation in conserved (18S small subunit) and variable (ITS-1) portions of ribosomal DNA from a large sample of Sarcocystis cruzi occurring in taurine beef cattle raised in the United States and Uruguay, and compared these data to available homologues, including those reported from zebu cattle, water buffalo, and bison. For additional context, we compared the apparent diversity of cattle parasites to that reported from congeneric parasites in other hosts.

Parelaphostrongylus odocoilei in Columbian black-tailed deer from Oregon.

Documenting the occurrence of Parelaphostrongylus odocoilei has historically relied on the morphological examination of adult worms collected from the skeletal muscle of definitive hosts, including deer. Recent advances in the knowledge of protostrongylid genetic sequences now permit larvae to be identified. Dorsal-spined larvae (DSLs) collected in 2003-2004 from the lung and feces of six Columbian black-tailed deer (Odocoileus hemionus columbianus) from Oregon were characterized genetically.

Population genetics of duplicated disease-defense genes, hm1 and hm2, in maize (Zea mays ssp. mays L.) and its wild ancestor (Zea mays ssp. parviglumis).

Plant defense genes are subject to nonneutral evolutionary dynamics. Here we investigate the evolutionary dynamics of the duplicated defense genes hm1 and hm2 in maize and its wild ancestor Zea mays ssp. parviglumis.