BackgroundAnaplasma phagocytophilum is the etiological agent of granulocytic anaplasmosis in humans and animals. Wild animals and ticks play key roles in the enzootic cycles of the pathogen. Potential ecotypes of A. phagocytophilum have been characterized genetically, but their host range, zoonotic potential and transmission dynamics has only incompletely been resolved.MethodsThe presence of A. phagocytophilum DNA was determined in more than 6000 ixodid ticks collected from the vegetation and wildlife, in 289 tissue samples from wild and domestic animals, and 69 keds collected from deer, originating from various geographic locations in The Netherlands and Belgium. From the qPCR-positive lysates, a fragment of the groEL-gene was amplified and sequenced. Additional groEL sequences from ticks and animals from Europe were obtained from GenBank, and sequences from human cases were obtained through literature searches. Statistical analyses were performed to identify A. phagocytophilum ecotypes, to assess their host range and their zoonotic potential. The population dynamics of A. phagocytophilum ecotypes was investigated using population genetic analyses.ResultsDNA of A. phagocytophilum was present in all stages of questing and feeding Ixodes ricinus, feeding I. hexagonus, I. frontalis, I. trianguliceps, and deer keds, but was absent in questing I. arboricola and Dermacentor reticulatus. DNA of A. phagocytophilum was present in feeding ticks and tissues from many vertebrates, including roe deer, mouflon, red foxes, wild boar, sheep and hedgehogs but was rarely found in rodents and birds and was absent in badgers and lizards. Four geographically dispersed A. phagocytophilum ecotypes were identified, that had significantly different host ranges. All sequences from human cases belonged to only one of these ecotypes. Based on population genetic parameters, the potentially zoonotic ecotype showed significant expansion.ConclusionFour ecotypes of A. phagocytophilum with differential enzootic cycles were identified. So far, all human cases clustered in only one of these ecotypes. The zoonotic ecotype has the broadest range of wildlife hosts. The expansion of the zoonotic A. phagocytophilum ecotype indicates a recent increase of the acarological risk of exposure of humans and animals.Electronic supplementary materialThe online version of this article (doi:10.1186/1756-3305-7-365) contains supplementary material, which is available to authorized users.

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Summary1. The issue of competition between livestock and wild herbivores has remained contentious. We studied the diets and population structures of the mountain ungulate bharal Pseudois nayaur and seven species of livestock to evaluate whether or not they compete for forage. The study was conducted in the high altitude Spiti Valley, Indian Trans-Himalaya. 2. We compared resource (forage) availability and bharal population structures between rangelands differing in livestock density. Forage availability was estimated by clipping the standing graminoid biomass in sample plots. Livestock and bharal population structures were quantified through annual censuses. Seasonal diets of livestock were studied by direct observations, while those of bharal were quantified through feeding signs on vegetation. 3. We found that livestock grazing causes a significant reduction in the standing crop of forage. Graminoid availability per unit livestock biomass was three times greater in a moderately grazed rangeland compared with an intensively grazed one. 4. There was considerable diet overlap among the herbivore species. In summer, bharal, yak Bos grunniens , horse Equus caballus , cow Bos indicus , and dzomo (yak-cow hybrids) fed predominantly on graminoids, while donkey E. asinus , sheep Ovis aries , and goat Capra hircus , consumed both graminoids and herbs. The summer diet of bharal was a subset of the diets of three livestock species. In winter, depleted graminoid availability caused bharal, yak and horse to consume relatively more herbs, while the remaining livestock species fed predominantly on graminoids. Diet overlap was less in winter but, in both seasons, all important forage species in the bharal diet were consumed in substantial amounts by one or more species of livestock. 5.Comparison of the population structures of bharal between two rangelands differing in livestock density by c . 30% yielded evidence of resource competition. In the intensively grazed rangeland, bharal density was 63% lower, and bharal population showed poorer performance (lower young : adult female ratios). 6. Synthesis and applications . High diet overlap between livestock and bharal, together with density-dependent forage limitation, results in resource competition and a decline in bharal density. Under the present conditions of high livestock density and supplemental feeding, restricting livestock numbers and creating livestockfree areas are necessary measures for conserving Trans-Himalayan wild herbivores. Mediating competitive effects on bharal through supplemental feeding is not a feasible option.

A field experiment was conducted in the Nouragues Reserve, an undisturbed lowland rain forest in French Guiana, to test possible selective pressures towards higher seed value of Carapa procera by scatter-hoarders, and to quantify survival probabilities of seeds harvested and cached by red acouchies (Myoprocta exilis). The following hypotheses were also tested: (1) large seeds are more likely to be harvested by acouchies than small seeds; (2) large seeds are harvested by acouchies more quickly than small seeds; (3) large seeds harvested by acouchies have a higher probability than small seeds to be cached rather than eaten; (4) large seeds are cached further away and in lower densities than small seeds; (5) large seeds are recovered from caches and consumed at lower rates than small seeds; and (6) large seeds have higher survival probabilities than small seeds. All seeds were removed within 1.5 days, except for three seeds, which were removed 1-2 days later, thus hypothesis 1 was not confirmed. A total of 362 seeds were located after dispersal wherein 84% was cached and relatively few seeds (16%) were eaten, which confirms hypothesis 3. The distance at which acouchy caches were found immediately after dispersal was highly variable, both within and among plots. The nearest cache was found <1 m from the plot, from which the farthest was 124 m away. Cache distance increased with seed size, as predicted by hypothesis 4. There was also great variation in spatial isolation of acouchy caches, both within and among plots. Recovery of seeds did not necessarily lead to seed consumption since many seeds were reached or were not found again. Larger seeds had a higher probability of being recached rather than eaten while consumed seeds were found much closer to the cache site than recached seeds. These results support hypothesis 5. Seed mass strongly affected the fate pathways of seeds and how long seeds were kept in stock. The ultimate probability of survival increased with seed mass, as posited by hypothesis 6.

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