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Santiago Merino - One of the best experts on this subject based on the ideXlab platform.
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Hemoparasites and immunological parameters in Snow Bunting (Plectrophenax nivalis) nestlings
Polar Biology, 2018Co-Authors: Javier Martinez, Elisa P. Badás, L. Almazán, Arne Moksnes, Santiago Merino, Andrés BarbosaAbstract:Knowledge on hemoparasites and immunological parameters in wild birds with Arctic distribution is limited. In this study, we chose the Snow Bunting (Plectrophenax nivalis) as model species to address this issue. Using nestlings, we aimed at (i) detecting hemoparasites with vector-borne transmission (via microscopic and molecular methods) and nest-dwelling ectoparasites and at (ii) exploring the relationship between several immunological parameters and parasitism. Nestlings were infected by Lankesterella parasites but hemoparasites of the genera Plasmodium, Haemoproteus, Leucocytozoon, Trypanosoma, Hepatozoon or Babesia were not found. This result may indicate the lack of suitable dipteran vectors or the inability of haemosporidians to reproduce in the Arctic region. Inflammation in response to the phytohaemagglutinin (PHA) injection was negatively related to infection by Lankesterella and positively related to weight gain in nestlings. The number of leukocytes and IgG level were not related to infection or PHA response, although the relationship between IgG level and PHA immune response was marginally significant. Besides, nestlings reared in mite-infected nests showed higher IgG level than those reared in mite-free nests. Taken together, (i) the positive relationship between PHA response/weight gain and PHA response/IgG level could reflect the nestlings’ nutritional status; and (ii) the higher IgG level in nestlings reared in mite-infected nests may be the result of a specific immune response to mite antigens. Different parasites may alter distinct immunological parameters in birds breeding under extreme weather conditions.
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Multiple color patches and parasites in Sceloporus occidentalis: differential relationships by sex and infection.
Current zoology, 2018Co-Authors: Rodrigo Megía-palma, Santiago Merino, Javier Martinez, Dhanashree A. Paranjpe, Senda Reguera, Robert D. Cooper, Pauline Blaimont, Barry SinervoAbstract:Parasites generally have a negative influence on the color expression of their hosts. Sexual selection theory predicts resistant high-quality individuals should show intense coloration, whereas susceptible low-quality individuals would show poor coloration. However, intensely colored males of different species of Old and New World lizards were more often infected by hemoparasites. These results suggest that high-quality males, with intense coloration, would suffer higher susceptibility to hemoparasites. This hypothesis remains poorly understood and contradicts general theories on sexual selection. We surveyed a population of Sceloporus occidentalis for parasites and found infections by the parasite genera Lankesterella and Acroeimeria. In this population, both males and females express ventral blue and yellow color patches. Lankesterella was almost exclusively infecting males. The body size of the males significantly predicted the coloration of both blue and yellow patches. Larger males showed darker (lower lightness) blue ventral patches and more saturated yellow patches that were also orange-skewed. Moreover, these males were more often infected by Lankesterella than smaller males. The intestinal parasite Acroeimeria infected both males and females. The infection by intestinal parasites of the genus Acroeimeria was the best predictor for the chroma in the blue patch of the males and for hue in the yellow patch of the females. Those males infected by Acroeimeria expressed blue patches with significantly lower chroma than the uninfected males. However, the hue of the yellow patch was not significantly different between infected and uninfected females. These results suggest a different effect of Lankesterella and Acroeimeria on the lizards. On the one hand, the intense coloration of male lizards infected by Lankesterella suggested high-quality male lizards may tolerate it. On the other hand, the low chroma of the blue coloration of the infected males suggested that this coloration could honestly express the infection by Acroeimeria.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & Vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Dhanashree Paranjpe, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Robert Cooper, Francisco Ferri-yáñez, Barry Sinervo, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown. Methods In the present study, we characterised morphologically and molecularly the hemococcidian parasites (sporozoites) that infect three lizard hosts from North America and two from South America. Results In total, we generated 12 new 18S rRNA gene sequences of hemococcidian parasites infecting New World lizard hosts. By the microscopic examination of the smears we identified Schellackia golvani Rogier & Landau, 1975 (ex Anolis carolinensis Voigt) and Schellackia occidentalis Bonorris & Ball, 1955 (ex Uta stansburiana Baird & Girard and Sceloporus occidentalis Baird & Girard) in some samples, but the phylogenetic analysis indicated that all 18S rDNA sequences are distant from Schellackia species found in Old World lizards. In fact, the hemococcidian parasites detected in the New World lizards (including S. occidentalis and S. golvani ) were closely related to the genus Lankesterella Labbé, 1899. Consequently, we suggest these two species to be included within the genus Lankesterella . Conclusions Life history traits of hemococcidian parasites such as the type of host blood cells infected, host species or number of refractile bodies are not valid diagnostic characteristics to differentiate the parasites between the genera Schellackia and Lankesterella . Indeed, lankesterellid parasites with a different number of refractile bodies had a close phylogenetic origin. Based on the phylogenetic results we provide a systematic revision of the North American hemococcidians. Our recommendation is to include the species formerly described in the genus Schellackia that infect American lizards into Lankesterella (Lankesterellidae) as Lankesterella golvani (Rogier & Landau, 1975) n. comb and L. occidentalis (Bonorris & Ball, 1955) n. comb.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Francisco Ferri-yáñez, Barry Sinervo, Dhanashree A. Paranjpe, Robert D. Cooper, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown.
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Molecular characterization of haemococcidia genus Schellackia (Apicomplexa) reveals the polyphyletic origin of the family Lankesterellidae
Zoologica Scripta, 2014Co-Authors: Rodrigo Megía-palma, Javier Martinez, Santiago MerinoAbstract:The current taxonomy on the haemococcidia establishes that the two genera of protozoan parasites that integrate the family Lankesterellidae are Lankesterella and Schellackia. However, the phylogeny of these genera, as well as the other coccidia, remains unresolved. In this sense, the use of type and described species is essential for the resolution of systematic conflicts. In this study, we molecularly characterize the type species of the genus Schellackia, that is, S. bolivari from Europe and also a described species of the same genus from Asia. At the same time, we contribute with the molecular characterization of another species of the genus Lankesterella. All this put together supports the polyphyly of the family Lankesterellidae. Therefore, we propose the resurrection of the zoological family, Schellackiidae Grasse 1953, to include species within the genus Schellackia.
Rodrigo Megía-palma - One of the best experts on this subject based on the ideXlab platform.
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To cool or not to cool? Intestinal coccidians disrupt the behavioral hypothermia of lizards in response to tick infestation.
Ticks and tick-borne diseases, 2019Co-Authors: Rodrigo Megía-palma, Dhanashree A. Paranjpe, Pauline Blaimont, R. Cooper, Barry SinervoAbstract:It is generally accepted that parasites exert negative effects on their hosts and that natural selection favors specific host responses that mitigate this impact. It is also known that some components of the host immune system often co-evolve with parasite antigens resulting in a host-parasite arms race. In addition to immunological components of the anti-parasitic response, host behavioral responses are also important in this arms race and natural selection may favor avoidance strategies that preclude contact with parasites, or shifts in the host's thermoregulatory strategy to combat active infections (e.g., behavioral fever). Ticks are widespread parasites with direct and indirect costs on their vertebrate hosts. Their saliva provokes hemolysis in the blood of their hosts and can transmit a plethora of tick-borne pathogens. We enquired whether tick infestation by Ixodes pacificus can provoke a thermoregulatory response in Sceloporus occidentalis. For this, we compared the thermoregulatory behavior of tick-infested lizards against tick-infested lizards co-infected with two different species of coccidians (Lankesterella occidentalis and Acroeimeria sceloporis). After this, lizards were kept in individual terraria with a basking spot and fed ad libitum. We found that tick-infested lizards sought cooler temperatures in proportion to their tick load, and this response was independent of the co-infection status by L. occidentalis. This was consistent in April and June (when tick loads were significantly lower) and suggests a conservative strategy to save energy which might have been selected to overcome tick infestations during phenological peaks of this parasite. However, this behavior was not observed in lizards co-infected with A. sceloporis, suggesting that co-infection with this intestinal parasite prompt lizards to be active. Cost of tick infestation was confirmed because housed lizards lost weight at a constant ratio to initial tick load, independently of other infections. The broader implications of these findings are discussed in the context of climate change.
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Multiple color patches and parasites in Sceloporus occidentalis: differential relationships by sex and infection.
Current zoology, 2018Co-Authors: Rodrigo Megía-palma, Santiago Merino, Javier Martinez, Dhanashree A. Paranjpe, Senda Reguera, Robert D. Cooper, Pauline Blaimont, Barry SinervoAbstract:Parasites generally have a negative influence on the color expression of their hosts. Sexual selection theory predicts resistant high-quality individuals should show intense coloration, whereas susceptible low-quality individuals would show poor coloration. However, intensely colored males of different species of Old and New World lizards were more often infected by hemoparasites. These results suggest that high-quality males, with intense coloration, would suffer higher susceptibility to hemoparasites. This hypothesis remains poorly understood and contradicts general theories on sexual selection. We surveyed a population of Sceloporus occidentalis for parasites and found infections by the parasite genera Lankesterella and Acroeimeria. In this population, both males and females express ventral blue and yellow color patches. Lankesterella was almost exclusively infecting males. The body size of the males significantly predicted the coloration of both blue and yellow patches. Larger males showed darker (lower lightness) blue ventral patches and more saturated yellow patches that were also orange-skewed. Moreover, these males were more often infected by Lankesterella than smaller males. The intestinal parasite Acroeimeria infected both males and females. The infection by intestinal parasites of the genus Acroeimeria was the best predictor for the chroma in the blue patch of the males and for hue in the yellow patch of the females. Those males infected by Acroeimeria expressed blue patches with significantly lower chroma than the uninfected males. However, the hue of the yellow patch was not significantly different between infected and uninfected females. These results suggest a different effect of Lankesterella and Acroeimeria on the lizards. On the one hand, the intense coloration of male lizards infected by Lankesterella suggested high-quality male lizards may tolerate it. On the other hand, the low chroma of the blue coloration of the infected males suggested that this coloration could honestly express the infection by Acroeimeria.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & Vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Dhanashree Paranjpe, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Robert Cooper, Francisco Ferri-yáñez, Barry Sinervo, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown. Methods In the present study, we characterised morphologically and molecularly the hemococcidian parasites (sporozoites) that infect three lizard hosts from North America and two from South America. Results In total, we generated 12 new 18S rRNA gene sequences of hemococcidian parasites infecting New World lizard hosts. By the microscopic examination of the smears we identified Schellackia golvani Rogier & Landau, 1975 (ex Anolis carolinensis Voigt) and Schellackia occidentalis Bonorris & Ball, 1955 (ex Uta stansburiana Baird & Girard and Sceloporus occidentalis Baird & Girard) in some samples, but the phylogenetic analysis indicated that all 18S rDNA sequences are distant from Schellackia species found in Old World lizards. In fact, the hemococcidian parasites detected in the New World lizards (including S. occidentalis and S. golvani ) were closely related to the genus Lankesterella Labbé, 1899. Consequently, we suggest these two species to be included within the genus Lankesterella . Conclusions Life history traits of hemococcidian parasites such as the type of host blood cells infected, host species or number of refractile bodies are not valid diagnostic characteristics to differentiate the parasites between the genera Schellackia and Lankesterella . Indeed, lankesterellid parasites with a different number of refractile bodies had a close phylogenetic origin. Based on the phylogenetic results we provide a systematic revision of the North American hemococcidians. Our recommendation is to include the species formerly described in the genus Schellackia that infect American lizards into Lankesterella (Lankesterellidae) as Lankesterella golvani (Rogier & Landau, 1975) n. comb and L. occidentalis (Bonorris & Ball, 1955) n. comb.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Francisco Ferri-yáñez, Barry Sinervo, Dhanashree A. Paranjpe, Robert D. Cooper, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown.
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Phylogenetic relationships of Isospora, Lankesterella, and Caryospora species (Apicomplexa: Eimeriidae) infecting lizards
Organisms Diversity & Evolution, 2016Co-Authors: Rodrigo Megía-palma, Javier Martinez, Intissar Nasri, José Javier Cuervo, José Martín, Iván Acevedo, Josabel Belliure, Jesús Ortega, Roberto García-roa, Slaheddine SelmiAbstract:In this study, several species of Isospora infecting lizards were genetically characterized. Specifically, five described and four newly described species of Isospora were included in a phylogeny of the family Eimeriidae. These species were isolated from hosts originally inhabiting all geographic continents except Europe. Phylogenetic analyses of the 18S ribosomal RNA (rRNA) gene grouped these nine species of Isospora with Lankesterella species and Caryospora ernsti . Therefore, within this clade, different evolutionary strategies in oocyst development and transmission occurred. Although the characteristic endogenous oocyst development of the genus Lankesterella may have arisen only once, the reduction in the number of sporocysts observed in the genus Caryospora occurred at least twice during coccidian evolution, as evidenced by the phylogenetic position of Caryospora bigenetica as the sister taxon of the group formed by reptilian Isospora , Lankesterella , and C. ernsti . Within this group, C. ernsti was the sister taxon to the genus Lankesterella . Overall, our results contradict the proposed monophyly of the genus Caryospora , highlighting the need for a thorough taxonomic and systematic revision of the group. Furthermore, they suggest that the recent ancestor of the genus Lankesterella may have been heteroxenous.
Javier Martinez - One of the best experts on this subject based on the ideXlab platform.
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Hemoparasites and immunological parameters in Snow Bunting (Plectrophenax nivalis) nestlings
Polar Biology, 2018Co-Authors: Javier Martinez, Elisa P. Badás, L. Almazán, Arne Moksnes, Santiago Merino, Andrés BarbosaAbstract:Knowledge on hemoparasites and immunological parameters in wild birds with Arctic distribution is limited. In this study, we chose the Snow Bunting (Plectrophenax nivalis) as model species to address this issue. Using nestlings, we aimed at (i) detecting hemoparasites with vector-borne transmission (via microscopic and molecular methods) and nest-dwelling ectoparasites and at (ii) exploring the relationship between several immunological parameters and parasitism. Nestlings were infected by Lankesterella parasites but hemoparasites of the genera Plasmodium, Haemoproteus, Leucocytozoon, Trypanosoma, Hepatozoon or Babesia were not found. This result may indicate the lack of suitable dipteran vectors or the inability of haemosporidians to reproduce in the Arctic region. Inflammation in response to the phytohaemagglutinin (PHA) injection was negatively related to infection by Lankesterella and positively related to weight gain in nestlings. The number of leukocytes and IgG level were not related to infection or PHA response, although the relationship between IgG level and PHA immune response was marginally significant. Besides, nestlings reared in mite-infected nests showed higher IgG level than those reared in mite-free nests. Taken together, (i) the positive relationship between PHA response/weight gain and PHA response/IgG level could reflect the nestlings’ nutritional status; and (ii) the higher IgG level in nestlings reared in mite-infected nests may be the result of a specific immune response to mite antigens. Different parasites may alter distinct immunological parameters in birds breeding under extreme weather conditions.
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Multiple color patches and parasites in Sceloporus occidentalis: differential relationships by sex and infection.
Current zoology, 2018Co-Authors: Rodrigo Megía-palma, Santiago Merino, Javier Martinez, Dhanashree A. Paranjpe, Senda Reguera, Robert D. Cooper, Pauline Blaimont, Barry SinervoAbstract:Parasites generally have a negative influence on the color expression of their hosts. Sexual selection theory predicts resistant high-quality individuals should show intense coloration, whereas susceptible low-quality individuals would show poor coloration. However, intensely colored males of different species of Old and New World lizards were more often infected by hemoparasites. These results suggest that high-quality males, with intense coloration, would suffer higher susceptibility to hemoparasites. This hypothesis remains poorly understood and contradicts general theories on sexual selection. We surveyed a population of Sceloporus occidentalis for parasites and found infections by the parasite genera Lankesterella and Acroeimeria. In this population, both males and females express ventral blue and yellow color patches. Lankesterella was almost exclusively infecting males. The body size of the males significantly predicted the coloration of both blue and yellow patches. Larger males showed darker (lower lightness) blue ventral patches and more saturated yellow patches that were also orange-skewed. Moreover, these males were more often infected by Lankesterella than smaller males. The intestinal parasite Acroeimeria infected both males and females. The infection by intestinal parasites of the genus Acroeimeria was the best predictor for the chroma in the blue patch of the males and for hue in the yellow patch of the females. Those males infected by Acroeimeria expressed blue patches with significantly lower chroma than the uninfected males. However, the hue of the yellow patch was not significantly different between infected and uninfected females. These results suggest a different effect of Lankesterella and Acroeimeria on the lizards. On the one hand, the intense coloration of male lizards infected by Lankesterella suggested high-quality male lizards may tolerate it. On the other hand, the low chroma of the blue coloration of the infected males suggested that this coloration could honestly express the infection by Acroeimeria.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & Vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Dhanashree Paranjpe, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Robert Cooper, Francisco Ferri-yáñez, Barry Sinervo, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown. Methods In the present study, we characterised morphologically and molecularly the hemococcidian parasites (sporozoites) that infect three lizard hosts from North America and two from South America. Results In total, we generated 12 new 18S rRNA gene sequences of hemococcidian parasites infecting New World lizard hosts. By the microscopic examination of the smears we identified Schellackia golvani Rogier & Landau, 1975 (ex Anolis carolinensis Voigt) and Schellackia occidentalis Bonorris & Ball, 1955 (ex Uta stansburiana Baird & Girard and Sceloporus occidentalis Baird & Girard) in some samples, but the phylogenetic analysis indicated that all 18S rDNA sequences are distant from Schellackia species found in Old World lizards. In fact, the hemococcidian parasites detected in the New World lizards (including S. occidentalis and S. golvani ) were closely related to the genus Lankesterella Labbé, 1899. Consequently, we suggest these two species to be included within the genus Lankesterella . Conclusions Life history traits of hemococcidian parasites such as the type of host blood cells infected, host species or number of refractile bodies are not valid diagnostic characteristics to differentiate the parasites between the genera Schellackia and Lankesterella . Indeed, lankesterellid parasites with a different number of refractile bodies had a close phylogenetic origin. Based on the phylogenetic results we provide a systematic revision of the North American hemococcidians. Our recommendation is to include the species formerly described in the genus Schellackia that infect American lizards into Lankesterella (Lankesterellidae) as Lankesterella golvani (Rogier & Landau, 1975) n. comb and L. occidentalis (Bonorris & Ball, 1955) n. comb.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Francisco Ferri-yáñez, Barry Sinervo, Dhanashree A. Paranjpe, Robert D. Cooper, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown.
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Phylogenetic relationships of Isospora, Lankesterella, and Caryospora species (Apicomplexa: Eimeriidae) infecting lizards
Organisms Diversity & Evolution, 2016Co-Authors: Rodrigo Megía-palma, Javier Martinez, Intissar Nasri, José Javier Cuervo, José Martín, Iván Acevedo, Josabel Belliure, Jesús Ortega, Roberto García-roa, Slaheddine SelmiAbstract:In this study, several species of Isospora infecting lizards were genetically characterized. Specifically, five described and four newly described species of Isospora were included in a phylogeny of the family Eimeriidae. These species were isolated from hosts originally inhabiting all geographic continents except Europe. Phylogenetic analyses of the 18S ribosomal RNA (rRNA) gene grouped these nine species of Isospora with Lankesterella species and Caryospora ernsti . Therefore, within this clade, different evolutionary strategies in oocyst development and transmission occurred. Although the characteristic endogenous oocyst development of the genus Lankesterella may have arisen only once, the reduction in the number of sporocysts observed in the genus Caryospora occurred at least twice during coccidian evolution, as evidenced by the phylogenetic position of Caryospora bigenetica as the sister taxon of the group formed by reptilian Isospora , Lankesterella , and C. ernsti . Within this group, C. ernsti was the sister taxon to the genus Lankesterella . Overall, our results contradict the proposed monophyly of the genus Caryospora , highlighting the need for a thorough taxonomic and systematic revision of the group. Furthermore, they suggest that the recent ancestor of the genus Lankesterella may have been heteroxenous.
Gediminas Valkiūnas - One of the best experts on this subject based on the ideXlab platform.
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The buffy coat method: a tool for detection of blood parasites without staining procedures
Parasites & Vectors, 2020Co-Authors: Carolina R. F. Chagas, Rasa Binkienė, Mikas Ilgūnas, Tatjana Iezhova, Gediminas ValkiūnasAbstract:Background Blood parasites belonging to the Apicomplexa, Trypanosomatidae and Filarioidea are widespread in birds and have been studied extensively. Microscopical examination (ME) of stained blood films remains the gold standard method for the detection of these infections in birds, particularly because co-infections predominate in wildlife. None of the available molecular tools can detect all co-infections at the same time, but ME provides opportunities for this to be achieved. However, fixation, drying and staining of blood films as well as their ME are relatively time-consuming. This limits the detection of infected hosts during fieldwork when captured animals should be released soon after sampling. It is an obstacle for quick selection of donor hosts for parasite experimental, histological and other investigations in the field. This study modified, tested and described the buffy coat method (BCM) for quick diagnostics (~ 20 min/sample) of avian blood parasites. Methods Blood of 345 birds belonging to 42 species was collected, and each sample was examined using ME of stained blood films and the buffy coat, which was examined after centrifugation in capillary tubes and after being transferred to objective glass slides. Parasite detection using these methods was compared using sensitivity, specificity, positive and negative predictive values and Cohen’s kappa index. Results Haemoproteus , Leucocytozoon , Plasmodium , microfilariae, Trypanosoma and Lankesterella parasites were detected. BCM had a high sensitivity (> 90%) and specificity (> 90%) for detection of Haemoproteus and microfilariae infections. It was of moderate sensitivity (57%) and high specificity (> 90%) for Lankesterella infections, but of low sensitivity (20%) and high specificity (> 90%) for Leucocytozoon infections. Trypanosoma and Plasmodium parasites were detected only by BCM and ME, respectively. According to Cohen’s kappa index, the agreement between two diagnostic tools was substantial for Haemoproteus (0.80), moderate for Lankesterella (0.46) and fair for microfilariae and Leucocytozoon (0.28) infections. Conclusions BCM is sensitive and recommended as a quick and reliable tool to detect Haemoproteus , Trypanosoma and microfilariae parasites during fieldwork. However, it is not suitable for detection of species of Leucocytozoon and Plasmodium . BCM is a useful tool for diagnostics of blood parasite co-infections. Its application might be extended to studies of blood parasites in other vertebrates during field studies.
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The buffy coat method: a tool for detection of blood parasites without staining procedures.
Parasites & vectors, 2020Co-Authors: Carolina R. F. Chagas, Rasa Binkienė, Mikas Ilgūnas, Tatjana Iezhova, Gediminas ValkiūnasAbstract:Blood parasites belonging to the Apicomplexa, Trypanosomatidae and Filarioidea are widespread in birds and have been studied extensively. Microscopical examination (ME) of stained blood films remains the gold standard method for the detection of these infections in birds, particularly because co-infections predominate in wildlife. None of the available molecular tools can detect all co-infections at the same time, but ME provides opportunities for this to be achieved. However, fixation, drying and staining of blood films as well as their ME are relatively time-consuming. This limits the detection of infected hosts during fieldwork when captured animals should be released soon after sampling. It is an obstacle for quick selection of donor hosts for parasite experimental, histological and other investigations in the field. This study modified, tested and described the buffy coat method (BCM) for quick diagnostics (~ 20 min/sample) of avian blood parasites. Blood of 345 birds belonging to 42 species was collected, and each sample was examined using ME of stained blood films and the buffy coat, which was examined after centrifugation in capillary tubes and after being transferred to objective glass slides. Parasite detection using these methods was compared using sensitivity, specificity, positive and negative predictive values and Cohen’s kappa index. Haemoproteus, Leucocytozoon, Plasmodium, microfilariae, Trypanosoma and Lankesterella parasites were detected. BCM had a high sensitivity (> 90%) and specificity (> 90%) for detection of Haemoproteus and microfilariae infections. It was of moderate sensitivity (57%) and high specificity (> 90%) for Lankesterella infections, but of low sensitivity (20%) and high specificity (> 90%) for Leucocytozoon infections. Trypanosoma and Plasmodium parasites were detected only by BCM and ME, respectively. According to Cohen’s kappa index, the agreement between two diagnostic tools was substantial for Haemoproteus (0.80), moderate for Lankesterella (0.46) and fair for microfilariae and Leucocytozoon (0.28) infections. BCM is sensitive and recommended as a quick and reliable tool to detect Haemoproteus, Trypanosoma and microfilariae parasites during fieldwork. However, it is not suitable for detection of species of Leucocytozoon and Plasmodium. BCM is a useful tool for diagnostics of blood parasite co-infections. Its application might be extended to studies of blood parasites in other vertebrates during field studies.
Barry Sinervo - One of the best experts on this subject based on the ideXlab platform.
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To cool or not to cool? Intestinal coccidians disrupt the behavioral hypothermia of lizards in response to tick infestation.
Ticks and tick-borne diseases, 2019Co-Authors: Rodrigo Megía-palma, Dhanashree A. Paranjpe, Pauline Blaimont, R. Cooper, Barry SinervoAbstract:It is generally accepted that parasites exert negative effects on their hosts and that natural selection favors specific host responses that mitigate this impact. It is also known that some components of the host immune system often co-evolve with parasite antigens resulting in a host-parasite arms race. In addition to immunological components of the anti-parasitic response, host behavioral responses are also important in this arms race and natural selection may favor avoidance strategies that preclude contact with parasites, or shifts in the host's thermoregulatory strategy to combat active infections (e.g., behavioral fever). Ticks are widespread parasites with direct and indirect costs on their vertebrate hosts. Their saliva provokes hemolysis in the blood of their hosts and can transmit a plethora of tick-borne pathogens. We enquired whether tick infestation by Ixodes pacificus can provoke a thermoregulatory response in Sceloporus occidentalis. For this, we compared the thermoregulatory behavior of tick-infested lizards against tick-infested lizards co-infected with two different species of coccidians (Lankesterella occidentalis and Acroeimeria sceloporis). After this, lizards were kept in individual terraria with a basking spot and fed ad libitum. We found that tick-infested lizards sought cooler temperatures in proportion to their tick load, and this response was independent of the co-infection status by L. occidentalis. This was consistent in April and June (when tick loads were significantly lower) and suggests a conservative strategy to save energy which might have been selected to overcome tick infestations during phenological peaks of this parasite. However, this behavior was not observed in lizards co-infected with A. sceloporis, suggesting that co-infection with this intestinal parasite prompt lizards to be active. Cost of tick infestation was confirmed because housed lizards lost weight at a constant ratio to initial tick load, independently of other infections. The broader implications of these findings are discussed in the context of climate change.
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Multiple color patches and parasites in Sceloporus occidentalis: differential relationships by sex and infection.
Current zoology, 2018Co-Authors: Rodrigo Megía-palma, Santiago Merino, Javier Martinez, Dhanashree A. Paranjpe, Senda Reguera, Robert D. Cooper, Pauline Blaimont, Barry SinervoAbstract:Parasites generally have a negative influence on the color expression of their hosts. Sexual selection theory predicts resistant high-quality individuals should show intense coloration, whereas susceptible low-quality individuals would show poor coloration. However, intensely colored males of different species of Old and New World lizards were more often infected by hemoparasites. These results suggest that high-quality males, with intense coloration, would suffer higher susceptibility to hemoparasites. This hypothesis remains poorly understood and contradicts general theories on sexual selection. We surveyed a population of Sceloporus occidentalis for parasites and found infections by the parasite genera Lankesterella and Acroeimeria. In this population, both males and females express ventral blue and yellow color patches. Lankesterella was almost exclusively infecting males. The body size of the males significantly predicted the coloration of both blue and yellow patches. Larger males showed darker (lower lightness) blue ventral patches and more saturated yellow patches that were also orange-skewed. Moreover, these males were more often infected by Lankesterella than smaller males. The intestinal parasite Acroeimeria infected both males and females. The infection by intestinal parasites of the genus Acroeimeria was the best predictor for the chroma in the blue patch of the males and for hue in the yellow patch of the females. Those males infected by Acroeimeria expressed blue patches with significantly lower chroma than the uninfected males. However, the hue of the yellow patch was not significantly different between infected and uninfected females. These results suggest a different effect of Lankesterella and Acroeimeria on the lizards. On the one hand, the intense coloration of male lizards infected by Lankesterella suggested high-quality male lizards may tolerate it. On the other hand, the low chroma of the blue coloration of the infected males suggested that this coloration could honestly express the infection by Acroeimeria.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & Vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Dhanashree Paranjpe, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Robert Cooper, Francisco Ferri-yáñez, Barry Sinervo, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown. Methods In the present study, we characterised morphologically and molecularly the hemococcidian parasites (sporozoites) that infect three lizard hosts from North America and two from South America. Results In total, we generated 12 new 18S rRNA gene sequences of hemococcidian parasites infecting New World lizard hosts. By the microscopic examination of the smears we identified Schellackia golvani Rogier & Landau, 1975 (ex Anolis carolinensis Voigt) and Schellackia occidentalis Bonorris & Ball, 1955 (ex Uta stansburiana Baird & Girard and Sceloporus occidentalis Baird & Girard) in some samples, but the phylogenetic analysis indicated that all 18S rDNA sequences are distant from Schellackia species found in Old World lizards. In fact, the hemococcidian parasites detected in the New World lizards (including S. occidentalis and S. golvani ) were closely related to the genus Lankesterella Labbé, 1899. Consequently, we suggest these two species to be included within the genus Lankesterella . Conclusions Life history traits of hemococcidian parasites such as the type of host blood cells infected, host species or number of refractile bodies are not valid diagnostic characteristics to differentiate the parasites between the genera Schellackia and Lankesterella . Indeed, lankesterellid parasites with a different number of refractile bodies had a close phylogenetic origin. Based on the phylogenetic results we provide a systematic revision of the North American hemococcidians. Our recommendation is to include the species formerly described in the genus Schellackia that infect American lizards into Lankesterella (Lankesterellidae) as Lankesterella golvani (Rogier & Landau, 1975) n. comb and L. occidentalis (Bonorris & Ball, 1955) n. comb.
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Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?
Parasites & vectors, 2017Co-Authors: Rodrigo Megía-palma, Javier Martinez, Verónica D’amico, Rocío Aguilar, María Gabriela Palacios, Francisco Ferri-yáñez, Barry Sinervo, Dhanashree A. Paranjpe, Robert D. Cooper, Santiago MerinoAbstract:Background Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown.
