Host-ectoparasite specificity in a small mammal community in an area of Atlantic Rain Forest (Ilha Grande, State of Rio de Janeiro), Southeastern Brazil

The analyses of the ectoparasite species associated with a small mammal community on Ilha Grande, a coastal island in southern of the state of Rio de Janeiro, Brazil, evaluated the level of host-ectoparasite specificity. Was used the Jaccard index for qualitative data to analyse the similarity. The lowest value of similarity occurred between Proechimys iheringi and Marmosops incanus and between Sciurus aestuans and Nectomys squamipes (Cj = 0.08) and the highest between P. iheringi and Oxymycterus sp. (Cj = 0.33). This index showed a low value of similarity across the ectoparasite community. The only exception from this pattern of high host specificity occurred with P. iheringi and Oxymycterus sp., which shared five species of ectoparasites. The similarity values, for most of the cases, is smaller than 0.2.

Terrestrial mammal feces: a morphometric summary and description

The study of feces of terrestrial mammals brings out biological and ecological data such as the species presence, diet, behaviour, territory, parasitic fauna, and home-range use, which can be applied for conservation projects and support paleoecological research that use coprolites as the main source of study. Although the new biotechnological techniques allow more accurate data, the diagnosis based on morphometric analyses permits the primary identification of the taxonomic group origin to support the best choice of subsequent analyses. We present the compilation list of fecal shape and measurements available in the literature published in North America, Eastern and Southern Africa, Europe, and new data from Brazil. Shape and diameters are the best characteristics for taxonomic identification. Feces were assembled in 9 groups that reflect the Order, sometimes the Family, and even their common origin.

Future hotspots of terrestrial mammal loss.

Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world.

Population dynamics of intermediate snail hosts of Fasciola hepatica and some environmental factors in San Juan y Martinez municipality, Cuba

The variation of abundances of intermediate snail hosts of Fasciola hepatica in Cuba (Fossaria cubensis and Pseudosuccinea columella) was studied during one year under natural conditions at five sampling sites in San Juan y Martinez municipality, Pinar del Rio province, Cuba. The effect of some environmental variables on the lymnaeid abundances was also studied. A canonical correspondence analysis showed that both species do not generally occur together in the same habitat and that most factors affect them in an opposite fashion, although both of them correlate positively through time to the diversity of the habitats. F. cubensis prefers the sites that are in or closer to the city whereas P. columella is more abundant in rural sites. Lymnaeid abundances are mainly affected by nitrite and nitrate concentrations as well as by the abundance of the thiarid Tarebia granifera. F. cubensis is more abundant in polluted habitats with low densities (or absence) of T. granifera whereas P. columella prefers cleaner habitats and can coexist with the thiarid, even at its higher densities. The implications of divergent preferences of the two lymnaeids for the control of fasciolosis are discussed.

Molecular trees of trypanosomes incongruent with fossil records of hosts

Molecular trees of trypanosomes have confirmed conventionally accepted genera, but often produce topologies that are incongruent with knowledge of the evolution, systematics, and biogeography of hosts and vectors. These distorted topologies result largely from incorrect assumptions about molecular clocks. A host-based phylogenetic tree could serve as a broad outline against which the reasonability of molecular phylogenies could be evaluated. The host-based tree of trypanosomes presented here supports the " invertebrate first " hypothesis of trypansosome evolution, supports the monophyly of Trypanosomatidae, and indicates the digenetic lifestyle arose three times. An area cladogram of Leishmania supports origination in the Palaearctic during the Palaeocene.

Field trials of low dose Bayluscide on snail hosts of schistosome and selected non-target organisms in sahelian Cameroon

More than 85% of all cases of schistosomiasis in Cameroon occur in the northern sahelian half of the country representing 20% of the population. Several workers have advocated the integrated approach to schistosomiasis control, including snail control, but the death and decay of aquatic organisms, and fish kill that often follows Bayluscide application at the dose of 1g/m³ decrease its acceptability. The present study was designed to assess the effect of lower Bayluscide doses on snail host and non-target fish, frog, the tadpole kill. Bayluscide was applied to study ponds at concentrations of 0, 0.25, 0.5, and 1 g/m³ (ppm). Pre and post application assessment of snails hosts of schistosomes, fish, frog, and tadpole kill were carried out. All 0.25, 0.5, and 1 g/m³ Bayluscide concentrations reduced snail population significantly. Bayluscide concentration of 0.50 g/m³ applied in two rounds of 0.25 g/m³ resulted in high snail mortality and low lethality to fish, frogs, and tadpoles. Further studies are needed to assess the cost-effectiveness of Bayluscide in the control of schistosomiasis following the simplified approach.

Anatomical studies of sibling species within neotropical lymnaeids, snail intermediate hosts of fascioliasis

Several anatomical parameters of the reproductive system have been used to distinguish Lymnaea cubensis from L. viatrix, the snail hosts of fascioliasis in South America and the Caribbean area. Three samples have been collected in the type localities of L. cubensis (Cuba), L. viatrix var. A ventricosa (Argentina, Río Negro Lower Valley), and L. viatrix var. B elongata (Peru, Lima), respectively. Only one parameter, the relative lengths of the penis sheath and preputium, showed significant differences between L. viatrix var. ventricosa and the two other taxa. None of the studied parameters separated L. cubensis from L. viatrix var. elongata.

Intermediate and definitive hosts of Schistosoma mansoni in Corrientes province, Argentina

Corrientes province is located in the humid subtropical region of Argentina northeast on the left riverbank of Paraná River in the border with the South of Brazil. This is a region without schistosomiasis but planorbid and rodents that would serve as host of the life cycle of Schistosoma mansoni inhabit here. The objective of this work is to know the role of rodent as definitive host of schistosomiasis. Biomphalaria tenagophila (4 to 8 mm Ø) from Maloyas, exposed each to 10 miracidia of SJ2 strain of S. mansoni natives from Brazil were susceptible (5%). The degree of compatibility was Class II of Frandsen. Five wild rodents captured in the same ecological niche were exposed transcutaneously to infection with 40 cercariae for animal: two Olygoryzomys flavescens, two Holochilus braziliensis, and one Scapteromys tuncidus. Only one H. braziliensis eliminated eggs in feces. Prepatent period was of 83 days. With these feces, two of six (33.3%) B. tenagophila from Maloyas were infected with miracidium. It was demonstrated, in an area free of schistosomiasis, that life cycle S. mansoni is closed with planorbid and rodents that live in the same ecological niche.

First record in South America of Didymosulcus palati and Didymosulcus philobranchiarca (Digenea, Didymozoidae) with new hosts records and pathological alterations

Two species of Didymozoidae, Didymosulcus palati (Yamaguti 1970) and Didymosulcus philobranchiarca (Yamaguti 1970) were reported for the first time in South America, Atlantic Ocean, parasitizing three different tuna species from the coast of Rio de Janeiro, Brazil: Thunnus atlanticus (Lesson), Thunnus albacares (Bonnaterre) and Thunnus obesus (Lowe). Pairs of D. philobranchiarca were found on gill arches of T. albacares and T. obesus, in longitudinal rows of yellow cysts located inside grooves in the hard denticle palate (new site) of the three hosts species studied, and as disperse groups of cysts in the operculum (new site) and gill arches of T. atlanticus (new host record). D. palati occurred as disperse groups of encysted worm pairs in the gill arches of T. albacares and T. obesus and in gill arches and operculum of T. atlanticus (new host record). The pathological alterations induced by D. philobranchiarca in the palate of T. atlanticus are described for the first time. Original measurements and figures are presented.

The bladder wall under extreme stress condition: ultrastructural observations in a hibernating mammal.

Comparative ultrastructural observations are presented of the distended bladder of a hibernating dormouse (Muscardinus avellanarius) and a relaxed organ taken from an active animal. The distended bladder of the hibernating animal has an extremely thin wall lined with a three-layer urothelium. An osmiophilic coat lines the luminal surface of the urothelium in the hibernating animal, but it is very thin indeed in the specimen from the active dormouse. In the urothelium of the distended bladder, a larger number of fusiform vesicles (FVs, typical structures of the urothelium with asymmetric unit membrane) is found. On the contrary, lysosomes, multivesicular bodies, and interdigitation of plasma membrane between adjacent cells are all more frequent in the relaxed bladder of the active dormouse. Results suggest that hibernating animals can be a useful model for investigating the biology of epithelial cells in the mammalian bladder.

Distribution of Lymnaeidae (Mollusca: Pulmonata), intermediate snail hosts of Fasciola hepatica in Venezuela

An extensive malacological survey was carried out between 2005-2009 in order to clarify the exact number of lymnaeid species which may be intermediate hosts of Fasciola hepatica in Venezuela. Four species were discovered during this survey, including two local species: Lymnaea cubensis and Lymnaea cousini and two exotic species: Lymnaea truncatula and Lymnaea columella. The most common local species was L. cubensis which was found at 16 out of the 298 sampling sites. This species has a large distribution area throughout the Northern part of Venezuela and was encountered from sea level to an altitude of 1,802 m in state of Trujillo. The second local species L. cousini was collected at only two sites of the Andean Region at altitudes of 3,550 m and 4,040 m, respectively. The European L. truncatula was found at 24 sites all located in the states of Mérida and Táchira at an altitude varying between 1,540-4,000 m. The respective distribution areas of L. cubensis and L. truncatula do not appear to overlap, but more detailed malacological surveys are needed. The fourth lymnaeid species, L. columella was collected in a canal from Mérida at an altitude of 1,929 m and in an irrigation canal from the state of Guárico, at an altitude of 63 m. The role of these four lymnaeid species in the transmission of fascioliasis in Venezuela is discussed.

Bat flies on phyllostomid hosts in the Cerrado region: component community, prevalence and intensity of parasitism

Streblidae flies are specialised parasites of bat hosts, mainly phyllostomids. There is a high richness of streblids in the savannah-like Cerrado region; however, there is little quantitative data available in parasitological indices. Here, we describe the component community, prevalence and intensity of a streblid infestation on a phyllostomid bat assemblage in Serra da Bodoquena, a Cerrado region in Southwest Brazil. We conducted surveys by capturing and inspecting bat hosts during the seven-month period between October 2004-December 2005. All the ectoparasites found on the bats were collected in the field and then counted and identified in the laboratory. We captured 327 bats belonging to 13 species, of which eight species were parasitized by 17 species of streblids. Carollia perspicillata and Glossophaga soricina were infested with seven streblid species, whereas the other bat species were infested with four or fewer streblid species. Megistopoda proxima and Aspidoptera falcata flies were found on Sturnira lilium, and Trichobius joblingi was the most prevalent fly on C. perspicillata. Megistopoda aranea and Aspidoptera phyllostomatis were highly prevalent and had a high intensity of infestation on Artibeus planirostris. Overall comparisons of the available data suggest that the component communities of streblids vary more between the Cerrado and Atlantic Forest phytogeographical regions than between localities within the same phytogeographical region.

Demographic fitness of Belminus ferroae (Hemiptera: Triatominae) on three different hosts under laboratory conditions

Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (α) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed.

Ecology of cutaneous leishmaniasis in Sinai: linking parasites, vectors and hosts

Cutaneous leishmaniasis (CL) is a neglected clinical form of public health importance that is quite prevalent in the northern and eastern parts of Egypt. A comprehensive study over seven years (January 2005-December 2011) was conducted to track CL transmission with respect to both sandfly vectors and animal reservoirs. The study identified six sandfly species collected from different districts in North Sinai: Phlebotomus papatasi, Phlebotomus kazeruni, Phlebotomus sergenti, Phlebotomus alexandri, Sergentomyia antennata and Sergentomyia clydei. Leishmania (-)-like flagellates were identified in 15 P. papatasi individuals (0.5% of 3,008 dissected females). Rodent populations were sampled in the same districts where sandflies were collected and eight species were identified: Rattus norvegicus (n = 39), Rattus rattus frugivorous (n = 13), Rattus rattus alexandrinus (n = 4), Gerbillus pyramidum floweri (n = 38), Gerbillus andersoni (n = 28), Mus musculus (n = 5), Meriones sacramenti (n = 22) and Meriones crassus (n = 10). Thirty-two rodents were found to be positive for Leishmania infection (20.12% of 159 examined rodents). Only Leishmania major was isolated and identified in 100% of the parasite samples. The diversity of both the vector and rodent populations was examined using diversity indices and clustering approaches.

What spatial data do we need to develop global mammal conservation strategies?

Spatial data on species distributions are available in two main forms, point locations and distribution maps (polygon ranges and grids). The first are often temporally and spatially biased, and too discontinuous, to be useful (untransformed) in spatial analyses. A variety of modelling approaches are used to transform point locations into maps. We discuss the attributes that point location data and distribution maps must satisfy in order to be useful in conservation planning. We recommend that before point location data are used to produce and/or evaluate distribution models, the dataset should be assessed under a set of criteria, including sample size, age of data, environmental/geographical coverage, independence, accuracy, time relevance and (often forgotten) representation of areas of permanent and natural presence of the species. Distribution maps must satisfy additional attributes if used for conservation analyses and strategies, including minimizing commission and omission errors, credibility of the source/assessors and availability for public screening. We review currently available databases for mammals globally and show that they are highly variable in complying with these attributes. The heterogeneity and weakness of spatial data seriously constrain their utility to global and also sub-global scale conservation analyses.