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Parasites affect many aspects of host physiology and behavior, and thus are generally thought to negatively impact host fitness. However, changes in form of short-term parasite effects on host physiological markers have generally been overlooked in favor of fitness measures. Here, we studied flea (Oropsylla idahoensis and Oropsylla opisocroistis tuberculata) parasitism on a natural population of Columbian ground squirrels (Urocitellus columbianus) in Sheep River Provincial Park, AB, Canada. Fleas were experimentally added to adult female U. columbianus at physiologically demanding times, including birth, lactation and weaning of their young. The body mass of adult females, as well as their oxidative stress and immunity were recorded multiple times over the active season under flea-augmented and control conditions. We also measured the prevalence of an internal parasite (Trypanosoma otospermophili). Doubly labeled water (DLW) was intraperitoneally injected at peak lactation to examine energy expenditure. Effects of parasites on oxidative stress were only observed after offspring were weaned. There was no direct effect of experimentally heightened flea prevalence on energy use. A short-term 24 h mass loss (-17 g) was detected briefly after parasite addition, likely due to U. columbianus preferentially allocating time for grooming. Our parasite augmentation did not strongly affect hosts and suggested that shorttermphysiological effects were unlikely to culminate in long-termfitness consequences. Columbian ground squirrels appear to rapidly manage parasite costs, probably through grooming. [ABSTRACT FROM AUTHOR]

Genome sequence analysis of two strains collected in Canada at the end of the 1970s and deposited in 1998 at the Collection de l'Institut Pasteur has led to the taxonomic description of a novel fish-associated species in the genus Flavobacterium . Both strains, CIP 105534 T and CIP 105535, were yellow-pigmented, Gram-stain-negative, non-spore-forming rod-shaped bacteria that exhibited gliding motility. They grew aerobically in a temperature range from 5 to 30 °C with optimal growth at 25 °C on trypticase soy or Reasoner's 2A agar but they did not grow on marine agar. Their major fatty acid profiles were similar, consisting of iso-C 15 : 0 , C 16 : 1  ω7 c and/or iso-C 15 : 0 2-OH (shown as summed feature 3), C 16 : 0 3-OH, iso-C 17 : 0 3-OH and C 16 : 0 . The major polyamine was sym -homospermidine. Phosphatidylethanolamine and, most notably, ornithine-containing lipid OL2 and unidentified aminophospholipid APL1 were major polar lipids. A yellow pigment spot was visible after chromatographic analysis. The predominant respiratory quinone was MK-6. The G+C content of the two genomes was 34 mol% and their size was around 5.8 Mb. Comparison of the 16S rRNA gene sequences with those of the closely related type strains showed high levels of relatedness with Flavobacterium collinsii and Flavobacterium pectinovorum . All average nucleotide identity (ANI) and digital DNA-DNA hybridization values estimated against publicly available Flavobacterium genome assemblies were lower than 90 and 30 %, respectively. Phylogenetic, phenotypic and chemotaxonomic data indicated that the two strains represent a novel species of the genus Flavobacterium , for which the name Flavobacterium bizetiae sp. nov. is proposed. The type strain is CIP 105534 T (=LMG 1342 T ). The unique ability of F. bizetiae to use melibiose as a sole source of carbon could provide a simple phenotypic test to discriminate F. bizetiae from its closest relatives.