Fatal hepatic sarcocystosis in a free-ranging grizzly bear cub associated with Sarcocystis canis-like infection.

We describe herein fatal hepatic sarcocystosis in a free-ranging grizzly bear ( Ursus arctos horribilis) cub with apicomplexan infection of the liver and brain, both demonstrating 100% homology for Sarcocystis canis and S. arctosi. Fatal hepatic sarcocystosis in dogs has been etiologically associated with intrahepatic schizonts of S. canis. In black and polar bears, a S. canis-like organism produces schizonts in the liver and massive hepatic necrosis. Although intramuscular sarcocysts, taxa S. arctosi and S. ursusi, have been described in healthy brown and black bears, respectively, they have not been detected in bears with hepatic sarcocystosis, to our knowledge, and it is currently unknown whether bears represent an aberrant or intermediate host.

Bronchopneumonia associated with Mannheimia granulomatis infection in a Belgian hare ( Lepus europaeus).

Mannheimia granulomatis was first isolated from pneumonic European hares in the 1980s and has since been reported sporadically in pneumonic Swedish roe deer and Australian cattle. Although the pneumonic lesions caused by M. haemolytica in livestock have been extensively studied and reported, little is published with regard to the pneumonic lesions associated with M. granulomatis infection in any species. We describe the histopathology of purulent bronchopneumonia associated with M. granulomatis in a Belgian hare ( Lepus europaeus) resident in British Columbia, Canada, and compare the lesions with those caused by M. haemolytica in livestock.

The complete mitochondrial genomes of the sea lily Gymnocrinus richeri and the feather star Phanogenia gracilis: signature nucleotide bias and unique nad4L gene rearrangement within crinoids.

Complete DNA sequences have been determined for the mitochondrial genomes of the crinoids Phanogenia gracilis (15892 bp) and Gymnocrinus richeri (15966 bp). The mitochondrial genetic map of the stalkless feather star P. gracilis is identical to that of the comatulid feather star Florometra serratissima (Scouras, A., Smith, M.J., 2001. Mol. Biol. Evol. 18, 61-73). The mitochondrial gene order of the stalked crinoid G. richeri differs from that of F. serratissima and P. gracilis by the transposition of the nad4L protein gene. The G. richeri nad4L mitochondrial map position is unique among metazoa and is likely a derived feature in this stalked crinoid. Nucleotide compositional analyses of protein genes encoded on the major sense strand confirm earlier conclusions regarding a crinoid-distinctive T over C bias. All three crinoids exhibit high T levels in third codon positions, whereas other echinoderm classes favor A or C in the third codon position. The nucleotide bias is reflected in the relative synonymous codon usage patterns of crinoids versus other echinoderms. We suggest that the nucleotide bias of crinoids, in comparison to other echinoderms, indicates that a physical inversion of the origin of replication has occurred in the crinoid lineage. Evolutionary rate tests support the use of the cytochrome b (cob) gene in molecular phylogenetic analyses of echinoderms. A consensus echinoderm tree was generated based on cytochrome b nucleotide alignments that placed the asteroids as a sister group to a clade containing the ophiuroids and the (echinoids+holothuroids) with the crinoids basal to the rest of the echinoderm classes: [Crinoid,(Asteroid,(Ophiuroid,(Echinoid,Holothuroid)))].

Complete mitochondrial genome DNA sequence for two ophiuroids and a holothuroid: the utility of protein gene sequence and gene maps in the analyses of deep deuterostome phylogeny.

The complete mitochondrial genome sequences have been determined for the holothuroid Cucumaria miniata and two ophiuroid species Ophiopholis aculeata and Ophiura lütkeni. In addition, the nucleotide sequence of the mitochondrial protein-coding genes for the asteroid Pisaster ochraceus has been completed. Maximum-likelihood and LogDet distance analyses of concatenated protein-coding sequences produced a series of trees that did not conclusively support generally accepted models of echinoderm phylogeny. The ophiuroid data consistently demonstrated accelerated nucleotide divergence rates and lack of stationarity. This confounds the phylogenetic analyses. Molecular investigations using individual protein-coding gene alignments demonstrated that the cytochrome b gene exhibits the least deviation in rate and stationarity and generated some trees consistent with proposed echinoderm phylogenies. Phylogenies based on echinoderm mitochondrial gene rearrangements also proved problematic because of extensive variation in gene order between and within classes. A comparison of the two distinctive ophiuroid mitochondrial gene orders supports the hypothesis that O. lütkeni has a more derived mitochondrial gene order versus O. aculeata. The variation in the echinoderm mitochondrial gene maps reinforces the limitations of the application of mitochondrial gene rearrangements as a global phylogenetic tool.