PARÁSITOS SANGUÍNEOS DE MALARIA Y GÉNEROS RELACIONADOS (ORDEN: HAEMOSPORIDA) EN AVES DE MÉXICO: RECOMENDACIONES METODOLÓGICAS PARA CAMPO Y LABORATORIO

Malaria parasites and related genera (order: Haemosporida) in birds from Mexico: methodological recommendations for the field and laboratory. – Parasites from the order Haemosporida (phylum: Apicomplexa) are transmitted by blood-sucking insects (order Diptera) and infect a wide array of amphibians, reptiles, birds, and mammals. Four genera of these parasites have been reported in birds: Plasmodium, Haemoproteus, Fallisia, and Leucocytozoon. Most studies on this group of parasites have been conducted in North America and Europe. In the Neotropical region studies are still scarce but have recently increased. In Mexico, our literature survey reveals the existence of 17 published studies. However, in many of these studies we detected shortcomings in the correct preparation of blood smears, such as lack of fixing in methanol and inadequate staining, which makes parasite identification difficult and renders blood smears useless as material for museum collections. Furthermore, we find similar mistakes in more recent unpublished studies (conference presentations, theses). Here we make methodological recommendations for the correct preparation and processing of blood smears both in the field and the laboratory. Our aim is to provide practical help to ornithologists and parasitologists interested in working with this group of parasites, in order to obtain high quality material that can subsequently be deposited at museum collections

Tree diversity and composition in Mexican traditional smallholder cocoa agroforestry systems

The cultivation of cocoa is a commodity of great importance worldwide. In Mexico, cocoa is grown in Tabasco and Chiapas states in agroforestry systems since pre-Hispanic times, where cocoa is grown under the canopy of shade trees. Crops such as sugarcane and extensive livestock production have gradually reduced the area devoted to cocoa cultivation in the region. Yet, farmers keep small portions of the cocoa agroforestry systems to maintain the local floristic diversity. This practice seems to be a successful contribution to plant conservation. To determine the management practices used by farmers in the agroforestry cocoa systems and the diversity of products they harvest, a non-probabilistic sampling was carried out in 38 shade cocoa plots of 20 x 50 m each (19 in Tabasco and 19 in Chiapas). We counted and identified all trees with DBH >= 5 cm, recording their height. We estimated canopy cover at 20 points within each plot. Our results show no tree species richness differences between states, but there were differences at the municipality level; Pichucalco (Chiapas) had the highest tree species richness. Considering all tree species, there was a higher tree density in Tabasco than in Chiapas. Regarding only cocoa trees, there was also a higher abundance in Tabasco than in Chiapas. In both cases, farmers obtain a wide variety of products for self-consumption and local market sale from their cocoa agroforestry systems (e.g., timber, fruit, and grains). The wide floristic diversity in these agroecosystems aids native plant species conservation and could favor the increase of agroforestry plantations associated with cocoa cultivation.Peer reviewe

Abundance of White-fronted Parrots and diet of an urban parrot assemblage (Aves: Psittaciformes) in a green Neotropical city

Peer reviewe

Bloodmeal analysis reveals avian Plasmodium infections and broad host preferences of Culicoides (Diptera: Ceratopogonidae) vectors.

Changing environmental conditions and human encroachment on natural habitats bring human populations closer to novel sources of parasites, which might then develop into new emerging diseases. Diseases transmitted by host generalist vectors are of special interest due to their capacity to move pathogens into novel hosts. We hypothesize that humans using forests for recreation are exposed to a broad range of parasites from wild animals and their vectors. A corollary of this is that new vector-host, parasite-host, and vector-parasite associations could eventually develop. Thus, we expect to observe atypical vector-host associations. Using molecular bloodmeal analysis via amplification of the mtDNA COI gene we identified the vertebrate hosts of Culicoides (Diptera: Ceratopogonidae) species in a sub-urban forest of Southwestern Germany. Bloodmeals were also checked for haemosporidian infections by amplifying a fragment of the mtDNA cyt b gene. We identified a total of 20 Culicoides species, thirteen of which fed on humans. From 105 screened bloodmeals we obtained high quality sequences for 77 samples, 73 (94.8%) originated from humans, two from livestock (Bos taurus and Equus caballus), and two from wild birds (Sylvia atricapilla and Turdus merula). We found that four Culicoides species previously assumed to feed exclusively on either birds (C. kibunensis) or domestic mammals (C. chiopterus, C. deltus, C. scoticus) fed also on humans. A total of six Culicoides abdomens were infected with avian haemosporidian parasites (Plasmodium or Haemoproteus), four of those abdomens contained blood derived from humans. Our results suggest that parasites of wild animals may be transferred to humans through infectious bites of Culicoides vectors. Further, we show that Culicoides vectors believed to be a specialist on specific vertebrate groups can have plastic feeding preferences, and that Culicoides are susceptible to infection by Plasmodium parasites, though vector viability must still be experimentally demonstrated

Blood-parasites (Haemosporida) of wild birds captured at different land uses within a tropical seasonal dry forest matrix

Avian haemosporidians form a diverse group of vector-borne parasites that can cause detrimental effects on their hosts and threaten the conservation of susceptible species. We explored the prevalence and parasitemia of haemosporidians infecting wild birds from Sierra de Huautla Biosphere Reserve in Morelos, southern Mexico. Birds were caught using mist nets in three habitat conditions (conserved, disturbed, and agricultural) and during two seasons (rainy and dry). Thin blood smears were prepared from blood samples for microscopic analysis. We captured 142 birds belonging to 17 species. We identified Haemoproteus spp., Plasmodium spp., and microfilaria. Prevalence was similar among land-use types (conserved (26.3%), disturbed (36.4%) and agricultural (29.9%)), and between seasons (rainy (29.7%) and dry (29.3%)), but varied per parasite genus and group (Haemoproteus spp. (28.2%), Plasmodium spp. (2.1%), coinfections (5.6%), and microfilaria (4.9%)). Parasitemia was low in most birds (< 0.1% erythrocytes infected), and only one, with an unhealthy appearance, presented high parasitemia (> 0.5%). We reported for the first time 12 species of birds infected with haemosporidian parasites and 16 new host-parasite associations in total. This is the first study of blood parasites in this region and provides fundamental information for future research.Los hemosporidios aviares forman un grupo diverso de parásitos transmitidos por vectores que pueden perjudicar a sus hospederos y amenazar la conservación de especies susceptibles. Evaluamos la prevalencia y parasitemia de hemosporidios en aves silvestres de la Reserva de la Biósfera Sierra de Huautla, Morelos, al sur de México. Las aves se capturaron usando redes de niebla en tres tipos de hábitat (conservado, perturbado y agrícola) y durante dos temporadas (lluvias y secas). Se realizaron frotis de capa fina para su análisis microscópico. Capturamos 142 aves pertenecientes a 17 especies. Los parásitos presentes fueron Haemoproteus spp., Plasmodium spp., y microfilarias. La prevalencia fue similar entre tipos de uso de suelo (conservado (26.3 %), perturbado (36.4 %) y agrícola (29.9 %)) y temporadas (lluvias (29.7 %) y secas (29.3 %)), pero varió por género y grupo de parásito (Haemoproteus spp. (28.2%), Plasmodium spp. (2.1 %), coinfecciones (5.6 %), y microfilarias (4.9 %)). La mayoría de las aves presentó una parasitemia baja (< 0.1% de eritrocitos infectados) y solo una, con apariencia malsana, presentó alta parasitemia (> 0.5 %). Reportamos por primera vez la infección de hemoparásitos en 12 especies de aves y 16 nuevas asociaciones parásito-hospedero. Este es el primer estudio de hemoparásitos en esta región y proporciona información fundamental para investigaciones futuras

Different Meal, Same Flavor: Cospeciation and Host Switching of Haemosporidian Parasites in Some Non-Passerine Birds

BackgroundPrevious studies have shown that haemosporidian parasites (Haemoproteus(Parahaemoproteus) and Plasmodium) infecting passerine birds have an evolutionary history of host switching with little cospeciation, in particular at low taxonomic levels (e.g., below the family level), which is suggested as the main speciation mechanism of this group of parasites. Recent studies have characterized diverse clades of haemosporidian parasites (H. (Haemoproteus) and H. (Parahaemoproteus)) infecting non-passerine birds (e.g., Columbiformes, Pelecaniiformes). Here, we explore the cospeciation history of H. (Haemoproteus) and H. (Parahaemoproteus) parasites with their non-passerine hosts.MethodsWe sequenced the mtDNA cyt b gene of both haemosporidian parasites and their avian non-passerine hosts. We built Bayesian phylogenetic hypotheses and created concensus phylograms that were subsequently used to conduct cospeciation analyses. We used both a global cospeciation test, PACo, and an event-cost algorithm implemented in CoRe-PA.ResultsThe global test suggests that H. (Haemoproteus) and H. (Parahaemoproteus) parasites have a diversification history dominated by cospeciation events particularly at the family level. Host-parasite links from the PACo analysis show that host switching events are common within families (i.e., among genera and among species within genera), and occasionally across different orders (e.g., Columbiformes to Pelecaniiformes). Event-cost analyses show that haemosporidian coevolutionary history is dominated by host switching and some codivergence, but with duplication events also present. Genetic lineages unique to raptor species (e.g., FALC11) commonly switch between Falconiformes and Strigiformes.ConclusionsOur results corroborate previous findings that have detected a global cospeciation signal at the family taxonomic level, and they also support a history of frequent switching closer to the tips of the host phylogeny, which seems to be the main diversification mechanism of haemosporidians. Such dynamic host-parasite associations are relevant to the epidemiology of emerging diseases because low parasite host specificity is a prerequisite for the emergence of novel diseases. The evidence on host distributions suggests that haemosporidian parasites have the potential to rapidly develop novel host-associations. This pattern has also been recorded in fish-monogenean interactions, suggesting a general diversification mechanism for parasites when host choice is not restricted by ecological barriers

Effects of forest structure on the interaction between avian hosts, dipteran vectors and haemosporidian parasites

Abstract Background Forest habitats are important biodiversity refuges for a wide variety of bird species. Parasitism may modulate host species presence and abundance, and parasite effects can change according to forest management practices. Such processes are not well studied in vector-borne avian haemosporidians. We analyzed the effects of forest management on bird-dipteran-haemosporidian interactions, using seven common bird species in managed and unmanaged beech forest habitats in northeastern Germany. We assumed that forest structural heterogeneity affects parasite population parameters in avian hosts (i.e., prevalence and parasitemia), through its effect on the condition of the avian host but also through varying vector abundances. Results Parasite prevalence was high (about 80%) and homogeneous across different beech forest categories (i.e., young, old, unmanaged) and for all bird species, except Erithacus rubecula (35%). Parasitemia varied across bird species but not across forest categories within each avian species (lowest parasitemia were found in E. rubecula, Turdus merula, and Turdus philomelos). In our study system, we found that vector abundance was not the main driver of parasite dynamics. We found that forest structure affects parasite infection probability directly and potentially host condition via available resources that have to be used either to combat infections (i.e., high parasitemia) or to maintain a good body condition. Conclusions The effects of each of the predictors were bird species-specific, and we found that Diptera vectors were not the foremost influence in our host-vector-parasite system. Effects of forest habitat variables indicated that for most bird species in this study, habitat regulation of infection probability was more likely (i.e., E. rubecula, Fringilla coelebs, Sylvia atricapilla), whereas for Parus major habitat characteristics impacted first individuals' body condition and subsequently the probability of infection. Our findings emphasize the need of species-specific analyses and to use continuous forest structural parameters (e.g., the proportion of gap, south facing aspect) to better understand habitat and land use effects on host-vector-parasite dynamics