Alfonso Marzal

Universidad de Extremadura | UNEX · Department of Anatomy, Cellular Biology and Zoology

The knowledge of the diversity and geographic distribution of parasite species is the first step towards understanding processes of global epidemiology and species conservation. Despite recent increases in research on haemosporidian and haemogregarine parasites of reptiles and amphibians, we still know little about their diversity and parasite-host...

The increasing spread of vector‐borne diseases has resulted in severe health concerns for humans, domestic animals and wildlife, with changes in land use and the introduction of invasive species being among the main possible causes for this increase. We explored several ecological drivers potentially affecting the local prevalence and richness of a...

Usutu virus (USUV) is an emerging zoonotic arbovirus that has caused an increasing number of animal and human cases in Europe in recent years. Understanding the vector species and avian hosts involved in the USUV enzootic cycle in an area of active circulation is vital to anticipate potential outbreaks. Mosquitoes were captured in 2020, while wild...

Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds. Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native passerines, with exotic species underrepresented. However, introduced species may carry on and spread new pathogens to native species,...

The knowledge of the diversity and geographic distribution of parasite species is the first step towards understanding processes of global epidemiology and species conservation. Despite recent increases in research on reptiles and amphibians haemosporidian and haemogregarine parasites, we still know little about their diversity and parasite-host in...

Background Hosts are often simultaneously infected with several parasite species. These co-infections can lead to within-host interactions of parasites, including mutualism and competition, which may affect both virulence and transmission. Birds are frequently co-infected with different haemosporidian parasites, but very little is known about if an...

Introduction: Thrushes (Passeriformes: Turdidae) are small to medium-sized songbirds and one of the most popular groups of game birds in Europe. Several helminths have already been detected in Turdus spp. Since these birds are predominantly migratory and feed mainly on invertebrates (insects, earthworms, terrestrial crustaceans and snails), they ca...

Introduction: The range of striped dolphins (Stenella coeruleoalba) extends across the warm-temperate to tropical waters of the world and this cetacean is the most frequently occurring dolphin in the Mediterranean Sea. Tetraphyllidean merocercoids have been commonly reported from most cetacean species and some pinnipeds world-wide, including S. coe...

RESUMEN Se describen las figuras de animales de los emblemas, representados en las borduras de los tapices flamencos de la catedral de Badajoz. Se estudia el simbolismo de los animales y se establecen paralelismos formales con representaciones de iluminaciones medievales y de grabados renacentistas, así como de grabados de ilustraciones de libros d...

Parasites have evolved different strategies to increase their transmission from one host to another. The Adaptive Host Manipulation hypothesis states that parasites induce modifications of host phenotypes that could maximise parasite fitness. There are numerous examples of parasite manipulation across a wide range of host and parasite taxa. However...

Feather mites are bird ectoparasites that show variation in their morphological structures depending on the microhabitat and host specificity. The genus Zachvatkinia Dubinin, 1949 comprises 15 species mainly associated with birds from Procellariiformes and Charadriiformes orders and it is usually very abundant on their hosts. The species Zachvatkin...

Hybridization can result in novel allelic combinations which can impact the hybrid phenotype through changes in gene expression. While mis‐expression in F1 hybrids is well documented, how gene expression evolves in stabilized hybrid taxa remains an open question. As gene expression evolves in a stabilizing manner, break‐up of co‐evolved cis‐ and tr...

The barn swallow (Hirundo rustica) poses a number of fascinating scientific questions, including the taxonomic status of postulated subspecies. Here we obtained and assessed the sequence variation of 411 complete mitogenomes, mainly from the European H. r. rustica, but other subspecies as well. In almost every case, we observed subspecies-specific...

Vector-borne infectious diseases (e.g., malaria, dengue fever, and yellow fever) result from a parasite transmitted to humans and other animals by blood-feeding arthropods. They are major contributors to the global disease burden, as they account for nearly a fifth of all infectious diseases worldwide. The interaction between vectors and their host...

During development of the vertebrate retina, mitotic activity is defined as apical when is located at the external surface of the neuroepithelium or as non-apical when is found in more internal regions. Apical mitoses give rise to all retinal cell types. Non-apical mitoses are linked to committed horizontal cell precursors that subsequently migrate...

We explore the presence of zoonotic flaviviruses (West Nile virus (WNV) and Usutu virus (USUV)) neutralizing antibodies in rarely studied passerine bird species. We report, for the first time in Europe, WNV-specific antibodies in red avadavat and cetti’s warbler, and USUV in yellow-crowned bishop. The evidence of WNV and USUV circulating in residen...

Migratory birds are important carriers of pathogens such as viruses, bacteria and protozoa. Avian haemosporidia have been detected from many wild birds of Japan, but the infection status of migratory birds and transmission area are still largely unknown. Gallinago snipes are long-distance migratory shorebirds, and five species migrate to or through...

Oil spills have killed thousands of birds during the last 100 years, but nonlethal effects of oil spills on birds remain poorly studied. We measured phenotype characters in 819 eiders Somateria mollissima (279 whole birds and 540 wings) of which 13.6% were oiled. We tested the hypotheses that (a) the morphology of eiders does not change due to oil...

Hybridization is increasingly recognized as an important evolutionary force contributing novel variation for selection to act on. While mis-expression in F1 hybrids is well documented, how gene expression evolves in stabilized hybrid taxa and contributes novel variation remains an open question, especially for hybrid species without an increase in...

Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from N...

Avian malaria and related haemosporidians (genera Haemoproteus, Plasmodium and Leucocytozoon) infect most clades of bird. Although these parasites are present in almost all continents, they have been irregularly studied across different geographical regions. Despite the high bird diversity in Asia, the diversity of avian haemosporidians in this reg...

This study shows the distribution patterns of apoptotic cells and biomarkers of cellular senescence during the ontogeny of the retina in the zebra finch (T. guttata). Neurogenesis in this altricial bird species is intense in the retina at perinatal and post-hatching stages, as opposed to precocial bird species in which retinogenesis occurs entirely...

Birds secrete preen oil from the uropygial (preen) gland which is used to maintain feather integrity and communicate through odour. The uropygial secretion is believed to influence host attractiveness to biting insects, thereby altering the risk of infection by vector‐transmitted blood parasites. Previous studies have documented a presence of bacte...

This is an interactive map with every migratory track from this study. It is a vectorized image (".svg" file) that must be opened with Google Chrome browser. The functionality of the map is explained in the pdf "Appendix 2".

Many populations of migratory bird species are rapidly declining. As a requisite for targeting effective conservation efforts it is essential to determine the whereabouts of migrants yearround. However, our knowledge of migratory routes and spatial-temporal occurrence across periods of the annual cycle is still limited for most species. We used lig...

APRESENTAÇÃO Neste livro nós apresentamos a diversidade e os tipos de hemoparasitas de anfíbios, um breve histórico da descoberta dos parasitas sanguíneos, os vetores de parasitas sanguíneos, a patogenicidade de hemoparasitas, discutimos a conexão entre os parasitas sanguíneos, mudanças globais e declínios populacionais de anfíbios, e concluímos co...

The breeding period, a key stage in animal life histories, incurs high energy expenditure and there is often the possibility that parasite infections may compromise its success. Since defences against parasites are also costly to produce, individuals should optimise the allocation of limited available resources to reproduction activities or self-ma...

Esta publicación indaga y profundiza en los desconocidos tapices de la catedral de Badajoz. El estudio consta de ocho tapices flamencos, siete de los cuales forman una serie denominada "La fidelidad de Penélope" y un octavo, que se realizó unos años más tarde. La colección tiene su espacio en los llamados tapices de verdura o de boscaje, debido a q...

Las Enfermedades Infecciosas Emergentes (EIDs) son una grave amenaza para la salud de humanos, animales domésticos y fauna silvestre. Estas enfermedades son causadas por patógenos que han desarrollado multi-resistencia frente a medicamentos, o han incrementado su rango geográfico o de hospederos. Como resultado, millones de personas han muerto en l...

Broadening the field of classical parasitology research by integrating it with ecoimmunology has allowed us a better understanding of the effect of haemo-sporidians and to identify the most relevant factors that affect the health of birds. Despite the recent advances in avian malaria studies, the lack of experimentation remains the main obstacle fo...

In 1884, only 5 years after A. Laveran discovered agents of human malaria, Vassily Danilewsky reported the first description of the pathological effects of avian malaria on their bird hosts. Shortly after, Sir Ronald Ross carried out the first investigation on the life cycle of avian Plasmodium parasites, being the first to show that the malaria pa...

Invasive organisms are non-indigenous species that are introduced outside its natural range, where they expand and establish. These non-indigenous species colonize new habitats and undergo rapid proliferation, imposing severe ecological and health impacts on invaded ecosystems. However, not all the translocated species beyond their native range bec...

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 manage...

All the organisms have developed defensive against different (parasites, harsh environmental conditions or contaminants) to which they should face in their environments. To deal with these selective factors, birds have developed defensive mechanisms such as the uropygial gland, which produces a secretion acting as a physicochemical defensive barrie...

Parasites are globally widespread pathogenic organisms, which impose important selective forces upon their hosts. Thus, in accordance with the Adjustment to parasite pressure hypothesis, it is expected that defences among hosts vary relative to the selective pressure imposed by parasites. According to the latitudinal gradient in diversity, species...

Changes in environmental conditions, whether related or not to human activities, are continuously modifying the geographic distribution of vectors, which in turn affects the dynamics and distribution of vector-borne infectious diseases. Determining the main ecological drivers of vector distribution and how predicted changes in these drivers may alt...

Infectious diseases often vary seasonally in a predictable manner, and seasonality may be responsible for geographical differences in prevalence. In temperate regions, vector-borne parasites such as malaria are expected to evolve lower virulence and a time-varying strategy to invest more in transmission when vectors are available. A previous model...

The Tropics are home to the greatest biodiversity in the world, but tropical species are at risk due to anthropogenic activities, mainly land use change, habitat loss, invasive species, and pathogens. Over the past 20 years, the avian malaria and related parasites (Order: Haemosporida) systems have received increased attention in the tropical regio...

Background: Avian malaria parasites are a highly diverse group that commonly infect birds and have deleterious effects on their hosts. Some parasite lineages are geographically widespread and infect many host species in many regions. Bird migration, natural dispersal, invasive species and human-mediated introductions into areas where competent ins...

The bird retina offers an excellent model to investigate the mechanisms that coordinate the morphogenesis, histogenesis, and differentiation of neuron and glial cells. Although these developmental features have been intensively studied in the chicken (Gallus gallus, Linnaeus 1758), a precocial bird species, little is known about retinogenesis in al...

The presence of insect vectors is a key prerequisite for transmission of vector-borne disease such as avian haemosporidians. In general, the effects of land use change on Diptera vectors are not well studied; the response of vectors to forest management depends on vector species, as has been shown previously for the birds. We tested if abundance of...

Parasites are a selective force that shape host community structure and dynamics, but host communities can also influence parasitism. Understanding the dual nature from host-parasite interactions can be facilitated by quantifying the variation in parasite prevalence among host species and then comparing that variation to other ecological factors th...

Database used for all the statistical analyses. Plots were also based on this database. (ZIP)

Pairwise distance matrix within new parasite lineages detected in the present study (in bold) and close related parasite lineages according to parasite phylogenetic tree (S1 Fig). (DOCX)

Phylogenetic associations between Plasmodium and Haemoproteus parasites and their avian hosts. (TIFF)

Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial gland secretion has been proposed to have antimicrobial and...

Parasites are a selective force that shape host community structure and dynamics, but host communities can also influence parasitism. Understanding the dual nature from host-parasite interactions can be facilitated by quantifying the variation in parasite prevalence (i.e. the proportion of infected host individuals in a population) among host speci...

In migratory species breeding in temperate zones and wintering in tropical areas prevalence of blood parasites may be affected by migratory strategies and winter habitat choice. We explored if African winter habitat was linked to the probability of haemosporidian infection in the House Martin Delichon urbicum breeding in Spain, and tested for poten...

Biological invasions by exotic species impose substantial ecological, economic and social costs worldwide, being a major threat to biodiversity conservation. Because not all individuals introduced in the new environments become successful invaders, the identification of factors underlying variation in invasion success would be essential for evaluat...

Comparative developmental studies have shown that the retina of altricial fish and mammals is incompletely developed at birth, and that, during the first days of life, maturation proceeds rapidly. In contrast, precocial fish and mammals are born with fully differentiated retinas. Concerning birds, knowledge about retinal development is generally re...

We studied the prevalence and genetic diversity of malaria parasites in the poorly investigated spotless starling (Sturnus unicolor) breeding in central Spain, aiming to describe the phylogenetic relationships among them and with other haemosporidians infecting the genus Sturnus. A total of 180 nestlings and 180 adult individuals from four differen...

Previous studies have linked winter habitat with subsequent breeding phenology and physical condition of migratory birds, but few have found delayed effects of winter habitat on subsequent reproductive success. The aim of this study was to test if African winter habitat is related to subsequent reproductive success of house martins (Delichon urbicu...

Blood parasites such as haemogregarines and haemosporidians have been identified in almost all groups of vertebrates and may cause serious damages to their hosts. However, very little is known about biodiversity of these parasites and their effects on some groups of reptiles such as terrapins. Moreover, the information on virulence from blood paras...

Pathogens such as bacteria, fungi and malaria and related haemosporidians provoke negative effects on the fitness of their hosts. Animals have developed a range of defensive mechanisms to resist or eliminate these parasitic infections and their negative fitness costs. The uropygial gland secretion has been proposed to act as defensive barrier of sk...

Many chelonians have colourful dots, patches and stripes throughout their body that are made up, at least in part, of carotenoids. Therefore, turtles are very suitable models to study the evolution and functionality of carotenoid-based colouration. Recent studies suggested a close link between colouration and immune system in these taxa. However, m...

Emerging infectious diseases (EIDs) impose a burden on economies and public health. Because EIDs on wildlife are mainly affected by environmental and ecological factors, the study of EIDs in wildlife provides valuable insights to improve our understanding on their causes and their impact on global health. Malaria is an EID that has increased its pr...

Blood parasites such as haemogregarines and haemosporidians have been identified in almost all groups of vertebrates. However, very little is known about biodiversity of these parasites and their effects on some major groups of reptiles such as amphisbaenians, a distinctive group with many morphological and ecological adaptations to fossorial life....

Understanding connections between breeding, stopover and wintering grounds for long-distance migratory birds can provide important insight into factors influencing demography and the strength of carry-over effects among various periods of the annual cycle. Using previously described, multi-isotope (δ13C, δ15N, δ2H) feather isoscapes for Africa, we...

Se maestrearon 92 ejemplares de pihuichos decomisados por tráfico ilegal por las Autoridad Regional del Gobierno de San Martín. Los ejemplares se encontraban en el centro de rescate del Área de Gestión de Fauna Silvestre del Gobierno Regional de San Martín. La metodología empleada fue PCR anidada a partir de muestras de sangre tomadas de la vena br...

Background Animals have developed a wide range of defensive mechanisms against parasites to reduce the likelihood of infection and its negative fitness costs. The uropygial gland is an exocrine gland that produces antimicrobial and antifungal secretions with properties used as a defensive barrier on skin and plumage. This secretion has been propose...

Birds often face various stressors during feather renewing, for example, enduring infection with blood parasites. Because nutritional resources are typically limited, especially for wild animals, when an individual allocates energy to one physiological system, there is subsequently less for other processes, thereby requiring a trade-off. Surprising...

Blood parasites such as malaria and related haemosporidians commonly infect vertebrate species including birds. Understanding age-specific patterns of parasite infections is crucial for quantifying the fitness consequences of parasitism for hosts and for understanding parasite transmission dynamics. We analyzed longitudinal and cross-sectional infe...

Escape behaviour is the behaviour that birds and other animals display when already caught by a predator. An individual exhibiting higher intensity of such anti-predator behaviour could have greater probabilities of escape from predators. Parasites are known to affect different aspects of host behaviour to increase their own fitness. Vector-transmi...

The importance of plumage colour as an indicator of individual quality has long been in the focus of studies of sexual selection. We analysed melanin-based coloration in the dorsal feathers of barn swallows Hirundo rustica to investigate the reliability of this colour as an indicator of individual quality and how it relates to reproductive performa...

The identification of the regions where vector-borne diseases are transmitted is essential to study transmission patterns and to recognize future changes in environmental conditions that may potentially influence the transmission areas. SGS1, one of the lineages of Plasmodium relictum , is known to have active transmission in tropical Africa and te...

Some species of avian malaria parasites are invaders and responsible for diversity losses worldwide. Here we analyze the prevalence and genetic characterization of avian malaria and related haemosporidian parasites in Neotropical birds from two different regions of Peru. We detected an overall prevalence of 32.4 % comprising 12 infected bird specie...