Plasmodium brasilianum (APICOMPLEXA, PLASMODIDAE) IN THE CONGO MONKEY Alouatta brasilianum (PRIMA... more Plasmodium brasilianum (APICOMPLEXA, PLASMODIDAE) IN THE CONGO MONKEY Alouatta brasilianum (PRIMATE: CEBIDAE) OF COSTA RICA. EPIDEMIOLOGICAL IMPORTANCE RELATED TO HUMAN Plasmodium brasilianum, a malaria parasite of Primates, was found for the first time in Costa Rica in 6 of 104 howler monkeys (Alouatta palliata) studied. Animals were captured and anaesthesied with dards containing equal parts of tiletamine hidrochloride and Zolazepam (Zoletil®). To study blood parasites, smears were prepared, fixed in methyl alcohol and stained by Giemsa technique. Young and advanced trofozoites (band forms) as well as gametocytes and squizonts ("rosseta" forms) were found. Since this parasite is very similar to P. malariae, a human parasite that has been found in Costa Rica, the presence of P. brasilianum is discussed on the epidemiological point of view.
How to cite Complete issue More information about this article Journal's homepage in redalyc... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System
We examined genetic diversity of howler monkeys (Alouatta palliata) from Costa Rica. Blood sample... more We examined genetic diversity of howler monkeys (Alouatta palliata) from Costa Rica. Blood samples of howler monkeys were collected at various locations in Costa Rica, and electrophoresis of total plasma proteins yielded no variation. We also conducted starch gel electrophoresis of red cell isozymes and did not find variation for any of the 14 loci analyzed (i.e., ACP, ADA, CA2, EST, GPI, IDH, LDH-1, LDH-2, MDH, PGD, PGM-1, PGM-2, SOD, and TPI). These findings were compared with the levels of genetic variation for A. seniculus and A. belzebul from one Brazilian population. Four of the 14 isozymes (ADA, GPI, PGD, and SOD) showed more than one allele for these species. Both A. seniculus and A. belzebul from Brazil showed similar levels of genetic variation. The potential causes of the low genetic variation in A. palliata from Costa Rica are discussed. RESUMEN Se estudió la diversidad genética de los monos congo (Alouatta palliata) de Costa Rica. Se recolectaron muestras de sangre en varias localidades de Costa Rica. El análisis de las proteínas totales del plasma mediante electroforesis no mostró variación. El análisis de las isoenzimas de glóbulos rojos mediante electroforesis en geles de almidón tampoco mostró variación para ninguno de los 14 loci analizados (i.e., ACP, ADA, CA2, EST, GPI, IDH, LDH-1, LDH-2, MDH, PGD, PGM-1, PGM-2, SOD, y TPI). Estos resultados se compararon con los niveles de variación genética en A. seniculus y A. belzebul de una población de Brasil. Estas especies presentaron más de un alelo en 4 de las 14 isoenzimas analizadas (ADA, GPI, PGD, y SOD). Tanto A. seniculus como A. belzebul presentaron niveles comparables de variación genética. Se discuten las causas potenciales de la poca variación genética en A. palliata de Costa Rica.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
We examined the association between geographic distribution, ecological traits, life history, gen... more We examined the association between geographic distribution, ecological traits, life history, genetic diversity, and risk of extinction in nonhuman primate species from Costa Rica. All of the current nonhuman primate species from Costa Rica are included in the study; spider monkeys (Ateles geoffroyi), howling monkeys (Alouatta palliata), capuchins (Cebus capucinus), and squirrel monkeys (Saimiri oerstedii). Geographic distribution was characterized accessing existing databases. Data on ecology and life history traits were obtained through a literature review. Genetic diversity was characterized using isozyme electrophoresis. Risk of extinction was assessed from the literature. We found that species differed in all these traits. Using these data, we conducted a Pearson correlation between risk of extinction and ecological and life history traits, and genetic variation, for widely distributed species. We found a negative association between risk of extinction and population birth and growth rates; indicating that slower reproducing species had a greater risk of extinction. We found a positive association between genetic variation and risk of extinction; i.e., species showing higher genetic variation had a greater risk of extinction. The relevance of these traits for conservation efforts is discussed.
We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, S... more We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, Sigmodontinae), in a Biological Reserve in Costa Rica and found 8 (89%) to be infected with 2 Eimeria species which we describe here as new. Sporulated oocysts (n ¼ 20) of the first, Eimeria melanomytis n. sp., are cylindroidal and measure 20.1 3 13.3 lm (18-23 3 13-15); micropyle and oocyst residuum are both absent, but a bilobular polar granule is present. Its sporocysts are ovoidal, 10.5 3 7.4 lm (10-13 3 6-8) with a small Stieda body, but both substieda and parastieda bodies are absent; a spheroidal sporocyst residuum is present,~5 lm wide. Sporulated oocysts (n ¼ 20) of the second, Eimeria rebambensis n. sp., are subspheroidal, 21.2 3 17.0 lm (19-23 3 14-18); micropyle and oocyst residuum are both absent, but with a polar granule~2 lm wide. Sporocysts are elongate-ovoidal, 12.4 3 7.0 lm (11-14 3 6-9) with a distinct knob-like Stieda body, and a substieda body directly beneath it which is about twice as wide, but no parastieda body is present; the sporocyst residuum is an irregular mass composed of 8-10 globules scattered among the sporozoites, which are~10 3 5 lm, and have 1 refractile body at their wider end and a central nucleus. These are the first eimerians described from this rodent genus.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial c... more Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial cells of villi of the small intestine of experimentally-infected young dusky rice rats, Melanomys caliginosus, were studied. Giemsa-stained mucosal scrapings and histological sections were examined for all the stages. Eimeria melanomytis has 3 generations of meronts (M), different in size, shape and number of merozoites (m), and in size, shape and location of the nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 11-14 (m1), 7-10 (m2), and 20-30 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, complete the sexual cycle forming the unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally-infected dusky rice rats. Eimeria melanomytis was first described and reported in Costa Rica by Chinchilla et al. (2013) in the dusky rice rat, Melanomys caliginosus, captured in the protected Reserva Biólogica Alberto Manuel Brenes (REBAMB) in San Ramón, Alajuela, Costa Rica. The original description was based on features of the sporulated oocyst and there was no description of the endogenous life cycle. Therefore, we experimentally infected rice rats and, herein, describe the endogenous life cycle stages of this species.
The endogenous life cycle of Eimeria caliginosa was studied in experimentally-infected dusky rice... more The endogenous life cycle of Eimeria caliginosa was studied in experimentally-infected dusky rice rats, Melanomys caliginosus. All endogenous stages were located in the epithelial cells of villi in the small intestine. Both Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria caliginosa has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 20-33 (m1), 5-9 (m2), and 13-16 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, which conclude with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in the experimentally-infected dusky rice rats. In our ongoing work to understand the biodiversit...
... Autor : Calderón-Arguedas, Olger; Troyo-Rodríguez, Adriana; Solano-Chinchilla, Mayra;Sánchez-... more ... Autor : Calderón-Arguedas, Olger; Troyo-Rodríguez, Adriana; Solano-Chinchilla, Mayra;Sánchez-Porras, Ronald E ... de Costa Rica, Centro de Investigación en Enfermedades Tropicales (CIET), Departamento de Parasitología, Facultad de Microbiología, San José, CR E ...
Parasites have been investigated for some New World primates; however, very little is known about... more Parasites have been investigated for some New World primates; however, very little is known about ectoparasites and specifically fur mites. In this study, Alouatta palliata, Cebus capucinus, Saimiri oerstedii, and Ateles geoffroyi monkeys from different areas of Costa Rica were searched for fur mites. A total of 276 monkeys were evaluated, and 51 of them were positive for mites of the family Atopomelidae. Listrocarpus alouattae was identified on 22.3% of A. palliata; Listrocarpus capucinus on 12.8% of C. capucinus; and Listrocarpus costaricensis on 36.8% of S. oerstedii; No fur mites were found on A. geoffroyi. Sex was not considered a determinant of mite infestation, but prevalence was significantly higher in the Central Volcanic Mountain Range Conservation Area for L. alouattae (p=0.01) and in the Central Pacific Conservation Area for L. capucinus (p=0.002). These primate fur mites are highly host-specific. Differences in the geographical distribution may be due to monkey behavior and history, as well as to environmental conditions.
Trypanosoma from the howler monkey Alouatta palliata was studied. Measures, as well as its biolog... more Trypanosoma from the howler monkey Alouatta palliata was studied. Measures, as well as its biological characteristics (mice infection and failure to infect Triatominae) identify this parasite as Trypanosoma minasense.
Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the ne... more Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the need to finding natural antimalarial components that would be found on plants from the forest. Therefore, we decided to look for these components in Costa Rican plants from a protected forest area. Fresh and dry extracts of roots, bark, leaves, flowers and fruits of 25 plants from a biological reserve in Costa Rica, Reserva Biológica Alberto Manuel Brenes (REBAMB), were studied in vitro for the presence of substances with antimalarial activity. By studying the inhibition of P. berghei schizogony, we assessed the antimalarial activity of several plant extracts: Aphelandra aurantiaca, A. tridentata (Acanthaceae); Xanthosoma undipes (Araceae); Iriartea deltoidea (Arecaceae); Neurolaena lobata (Asteraceae); Senna papillosa, Pterocarpus hayessi, Lonchocarpus pentaphyllus (Fabaceae); Nectandra membranacea, Persea povedae, Cinamomum chavarrianum (Lauraceae); Hampea appendiculata (Malvaceae); Ruagea glabra, Guarea glabra (Meliaceae); Psidium guajava (Myrtaceae); Bocconia frutescens (Papaveraceae); Piper friedrichsthalii (Piperaceae); Clematis dioica (Ranunculaceae); Prunus annularis (Rosaceae); Siparuna thecaphora (Siparunaceae); Solanum arboreum, Witheringia solanacea (Solanaceae); Ticodendrum incognitum (Ticodendraceae); Heliocarpus appendiculatus (Tiliaceae) and Myriocarpa longipes (Urticaceae). We used different parts of the plants as well as fresh and dried extracts for testing IC50. The solid content of the extracts ranged from 1-71.9μg/mL. The fresh extracts showed stronger activity than the dry ones. Since the plants showing the strongest antimalarial activity are very common in Central America, and some similar genera of these plants have shown positives results in South America, we considered important to present these findings for discussion. On the other hand, this is the first systematic study of this kind ever realized in a circumscribed and protected area of Costa Rica. Rev. Biol. Trop. 60 (2): 881-891. Epub 2012 June 01.
A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eo... more A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eothen Zug is described from specimens collected in Papua New Guinea (PNG). Oöcysts of Eimeria zugi n. sp. from one of one (100%) C. eothen are ellipsoidal to cylindroidal, with a smooth, colourless, bi-layered wall, measure 25.1 9 15.5 lm and have a length/width ratio of 1.6. The micropyle and the oöcyst residuum are absent, but a polar granule is present. The sporocysts are ovoidal to ellipsoidal and 10.3 9 7.1 lm in size and do not contain Stieda, sub-Stieda or para-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites are elongate, 12.8 9 2.9 lm in size, and contain anterior and posterior refractile bodies with a nucleus between them. This is the ninth species of coccidium described from skinks from PNG, and the new species described herein is apparently endemic to the skink genus Carlia (Gray).
We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, S... more We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, Sigmodontinae), in a Biological Reserve in Costa Rica and found 8 (89%) to be infected with 2 Eimeria species which we describe here as new. Sporulated oocysts (n ¼ 20) of the first, Eimeria melanomytis n. sp., are cylindroidal and measure 20.1 3 13.3 lm (18-23 3 13-15); micropyle and oocyst residuum are both absent, but a bilobular polar granule is present. Its sporocysts are ovoidal, 10.5 3 7.4 lm (10-13 3 6-8) with a small Stieda body, but both substieda and parastieda bodies are absent; a spheroidal sporocyst residuum is present,~5 lm wide. Sporulated oocysts (n ¼ 20) of the second, Eimeria rebambensis n. sp., are subspheroidal, 21.2 3 17.0 lm (19-23 3 14-18); micropyle and oocyst residuum are both absent, but with a polar granule~2 lm wide. Sporocysts are elongate-ovoidal, 12.4 3 7.0 lm (11-14 3 6-9) with a distinct knob-like Stieda body, and a substieda body directly beneath it which is about twice as wide, but no parastieda body is present; the sporocyst residuum is an irregular mass composed of 8-10 globules scattered among the sporozoites, which are~10 3 5 lm, and have 1 refractile body at their wider end and a central nucleus. These are the first eimerians described from this rodent genus.
... 1998. Development of Alouattamyia baeri (Diptera: Oestridae) from howler monkeys (Primates: C... more ... 1998. Development of Alouattamyia baeri (Diptera: Oestridae) from howler monkeys (Primates: Cebidae) on Barro Colorado Island, Panama. J. Med. Entomol. 35: 674-680. Daniel, WW 1984. Bioestadistica: Base para el an~lisis de las ciencias de la salud. ...
We propose the first molecular systematic hypothesis for the origin and evolution of Cebus capuci... more We propose the first molecular systematic hypothesis for the origin and evolution of Cebus capucinus based on an analysis of 710 base pairs (bp) of the cytochrome c oxidase subunit II (COII) mitochondrial gene in 121 C. capucinus specimens sampled in the wild. The animals came from the borders of Guatemala and Belize, Costa Rica, and eight different departments of Colombia (Antioquia, Chocó, Sucre, Bolivar, Córdoba, Magdalena, Cauca, and Valle del Cauca). Three different and significant haplotype lineages were found in Colombia living sympatrically in the same departments. They all presented high levels of gene diversity but the third Colombian gene pool was determined likely to be the most ancestral lineage. The second Colombian mitochondrial (mt) haplogroup is likely the source of origin of the unique Central America mt haplogroup that was detected. Our molecular population genetics data do not agree with the existence of two well-defined subspecies in Central America (limitaneus and imitator). This Central America mt haplogroup showed significantly less genetic diversity than the Colombian mt haplogroups. All the C. capucinus analyzed showed evidence of historical population expansions. The temporal splits among these four C. capucinus lineages were related to the completion of the Panamanian land bridge as well as to climatic changes during the Quaternary Period.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
Plasmodium brasilianum (APICOMPLEXA, PLASMODIDAE) IN THE CONGO MONKEY Alouatta brasilianum (PRIMA... more Plasmodium brasilianum (APICOMPLEXA, PLASMODIDAE) IN THE CONGO MONKEY Alouatta brasilianum (PRIMATE: CEBIDAE) OF COSTA RICA. EPIDEMIOLOGICAL IMPORTANCE RELATED TO HUMAN Plasmodium brasilianum, a malaria parasite of Primates, was found for the first time in Costa Rica in 6 of 104 howler monkeys (Alouatta palliata) studied. Animals were captured and anaesthesied with dards containing equal parts of tiletamine hidrochloride and Zolazepam (Zoletil®). To study blood parasites, smears were prepared, fixed in methyl alcohol and stained by Giemsa technique. Young and advanced trofozoites (band forms) as well as gametocytes and squizonts ("rosseta" forms) were found. Since this parasite is very similar to P. malariae, a human parasite that has been found in Costa Rica, the presence of P. brasilianum is discussed on the epidemiological point of view.
How to cite Complete issue More information about this article Journal's homepage in redalyc... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System
We examined genetic diversity of howler monkeys (Alouatta palliata) from Costa Rica. Blood sample... more We examined genetic diversity of howler monkeys (Alouatta palliata) from Costa Rica. Blood samples of howler monkeys were collected at various locations in Costa Rica, and electrophoresis of total plasma proteins yielded no variation. We also conducted starch gel electrophoresis of red cell isozymes and did not find variation for any of the 14 loci analyzed (i.e., ACP, ADA, CA2, EST, GPI, IDH, LDH-1, LDH-2, MDH, PGD, PGM-1, PGM-2, SOD, and TPI). These findings were compared with the levels of genetic variation for A. seniculus and A. belzebul from one Brazilian population. Four of the 14 isozymes (ADA, GPI, PGD, and SOD) showed more than one allele for these species. Both A. seniculus and A. belzebul from Brazil showed similar levels of genetic variation. The potential causes of the low genetic variation in A. palliata from Costa Rica are discussed. RESUMEN Se estudió la diversidad genética de los monos congo (Alouatta palliata) de Costa Rica. Se recolectaron muestras de sangre en varias localidades de Costa Rica. El análisis de las proteínas totales del plasma mediante electroforesis no mostró variación. El análisis de las isoenzimas de glóbulos rojos mediante electroforesis en geles de almidón tampoco mostró variación para ninguno de los 14 loci analizados (i.e., ACP, ADA, CA2, EST, GPI, IDH, LDH-1, LDH-2, MDH, PGD, PGM-1, PGM-2, SOD, y TPI). Estos resultados se compararon con los niveles de variación genética en A. seniculus y A. belzebul de una población de Brasil. Estas especies presentaron más de un alelo en 4 de las 14 isoenzimas analizadas (ADA, GPI, PGD, y SOD). Tanto A. seniculus como A. belzebul presentaron niveles comparables de variación genética. Se discuten las causas potenciales de la poca variación genética en A. palliata de Costa Rica.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
We examined the association between geographic distribution, ecological traits, life history, gen... more We examined the association between geographic distribution, ecological traits, life history, genetic diversity, and risk of extinction in nonhuman primate species from Costa Rica. All of the current nonhuman primate species from Costa Rica are included in the study; spider monkeys (Ateles geoffroyi), howling monkeys (Alouatta palliata), capuchins (Cebus capucinus), and squirrel monkeys (Saimiri oerstedii). Geographic distribution was characterized accessing existing databases. Data on ecology and life history traits were obtained through a literature review. Genetic diversity was characterized using isozyme electrophoresis. Risk of extinction was assessed from the literature. We found that species differed in all these traits. Using these data, we conducted a Pearson correlation between risk of extinction and ecological and life history traits, and genetic variation, for widely distributed species. We found a negative association between risk of extinction and population birth and growth rates; indicating that slower reproducing species had a greater risk of extinction. We found a positive association between genetic variation and risk of extinction; i.e., species showing higher genetic variation had a greater risk of extinction. The relevance of these traits for conservation efforts is discussed.
We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, S... more We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, Sigmodontinae), in a Biological Reserve in Costa Rica and found 8 (89%) to be infected with 2 Eimeria species which we describe here as new. Sporulated oocysts (n ¼ 20) of the first, Eimeria melanomytis n. sp., are cylindroidal and measure 20.1 3 13.3 lm (18-23 3 13-15); micropyle and oocyst residuum are both absent, but a bilobular polar granule is present. Its sporocysts are ovoidal, 10.5 3 7.4 lm (10-13 3 6-8) with a small Stieda body, but both substieda and parastieda bodies are absent; a spheroidal sporocyst residuum is present,~5 lm wide. Sporulated oocysts (n ¼ 20) of the second, Eimeria rebambensis n. sp., are subspheroidal, 21.2 3 17.0 lm (19-23 3 14-18); micropyle and oocyst residuum are both absent, but with a polar granule~2 lm wide. Sporocysts are elongate-ovoidal, 12.4 3 7.0 lm (11-14 3 6-9) with a distinct knob-like Stieda body, and a substieda body directly beneath it which is about twice as wide, but no parastieda body is present; the sporocyst residuum is an irregular mass composed of 8-10 globules scattered among the sporozoites, which are~10 3 5 lm, and have 1 refractile body at their wider end and a central nucleus. These are the first eimerians described from this rodent genus.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial c... more Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial cells of villi of the small intestine of experimentally-infected young dusky rice rats, Melanomys caliginosus, were studied. Giemsa-stained mucosal scrapings and histological sections were examined for all the stages. Eimeria melanomytis has 3 generations of meronts (M), different in size, shape and number of merozoites (m), and in size, shape and location of the nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 11-14 (m1), 7-10 (m2), and 20-30 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, complete the sexual cycle forming the unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally-infected dusky rice rats. Eimeria melanomytis was first described and reported in Costa Rica by Chinchilla et al. (2013) in the dusky rice rat, Melanomys caliginosus, captured in the protected Reserva Biólogica Alberto Manuel Brenes (REBAMB) in San Ramón, Alajuela, Costa Rica. The original description was based on features of the sporulated oocyst and there was no description of the endogenous life cycle. Therefore, we experimentally infected rice rats and, herein, describe the endogenous life cycle stages of this species.
The endogenous life cycle of Eimeria caliginosa was studied in experimentally-infected dusky rice... more The endogenous life cycle of Eimeria caliginosa was studied in experimentally-infected dusky rice rats, Melanomys caliginosus. All endogenous stages were located in the epithelial cells of villi in the small intestine. Both Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria caliginosa has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 20-33 (m1), 5-9 (m2), and 13-16 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, which conclude with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in the experimentally-infected dusky rice rats. In our ongoing work to understand the biodiversit...
... Autor : Calderón-Arguedas, Olger; Troyo-Rodríguez, Adriana; Solano-Chinchilla, Mayra;Sánchez-... more ... Autor : Calderón-Arguedas, Olger; Troyo-Rodríguez, Adriana; Solano-Chinchilla, Mayra;Sánchez-Porras, Ronald E ... de Costa Rica, Centro de Investigación en Enfermedades Tropicales (CIET), Departamento de Parasitología, Facultad de Microbiología, San José, CR E ...
Parasites have been investigated for some New World primates; however, very little is known about... more Parasites have been investigated for some New World primates; however, very little is known about ectoparasites and specifically fur mites. In this study, Alouatta palliata, Cebus capucinus, Saimiri oerstedii, and Ateles geoffroyi monkeys from different areas of Costa Rica were searched for fur mites. A total of 276 monkeys were evaluated, and 51 of them were positive for mites of the family Atopomelidae. Listrocarpus alouattae was identified on 22.3% of A. palliata; Listrocarpus capucinus on 12.8% of C. capucinus; and Listrocarpus costaricensis on 36.8% of S. oerstedii; No fur mites were found on A. geoffroyi. Sex was not considered a determinant of mite infestation, but prevalence was significantly higher in the Central Volcanic Mountain Range Conservation Area for L. alouattae (p=0.01) and in the Central Pacific Conservation Area for L. capucinus (p=0.002). These primate fur mites are highly host-specific. Differences in the geographical distribution may be due to monkey behavior and history, as well as to environmental conditions.
Trypanosoma from the howler monkey Alouatta palliata was studied. Measures, as well as its biolog... more Trypanosoma from the howler monkey Alouatta palliata was studied. Measures, as well as its biological characteristics (mice infection and failure to infect Triatominae) identify this parasite as Trypanosoma minasense.
Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the ne... more Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the need to finding natural antimalarial components that would be found on plants from the forest. Therefore, we decided to look for these components in Costa Rican plants from a protected forest area. Fresh and dry extracts of roots, bark, leaves, flowers and fruits of 25 plants from a biological reserve in Costa Rica, Reserva Biológica Alberto Manuel Brenes (REBAMB), were studied in vitro for the presence of substances with antimalarial activity. By studying the inhibition of P. berghei schizogony, we assessed the antimalarial activity of several plant extracts: Aphelandra aurantiaca, A. tridentata (Acanthaceae); Xanthosoma undipes (Araceae); Iriartea deltoidea (Arecaceae); Neurolaena lobata (Asteraceae); Senna papillosa, Pterocarpus hayessi, Lonchocarpus pentaphyllus (Fabaceae); Nectandra membranacea, Persea povedae, Cinamomum chavarrianum (Lauraceae); Hampea appendiculata (Malvaceae); Ruagea glabra, Guarea glabra (Meliaceae); Psidium guajava (Myrtaceae); Bocconia frutescens (Papaveraceae); Piper friedrichsthalii (Piperaceae); Clematis dioica (Ranunculaceae); Prunus annularis (Rosaceae); Siparuna thecaphora (Siparunaceae); Solanum arboreum, Witheringia solanacea (Solanaceae); Ticodendrum incognitum (Ticodendraceae); Heliocarpus appendiculatus (Tiliaceae) and Myriocarpa longipes (Urticaceae). We used different parts of the plants as well as fresh and dried extracts for testing IC50. The solid content of the extracts ranged from 1-71.9μg/mL. The fresh extracts showed stronger activity than the dry ones. Since the plants showing the strongest antimalarial activity are very common in Central America, and some similar genera of these plants have shown positives results in South America, we considered important to present these findings for discussion. On the other hand, this is the first systematic study of this kind ever realized in a circumscribed and protected area of Costa Rica. Rev. Biol. Trop. 60 (2): 881-891. Epub 2012 June 01.
A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eo... more A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eothen Zug is described from specimens collected in Papua New Guinea (PNG). Oöcysts of Eimeria zugi n. sp. from one of one (100%) C. eothen are ellipsoidal to cylindroidal, with a smooth, colourless, bi-layered wall, measure 25.1 9 15.5 lm and have a length/width ratio of 1.6. The micropyle and the oöcyst residuum are absent, but a polar granule is present. The sporocysts are ovoidal to ellipsoidal and 10.3 9 7.1 lm in size and do not contain Stieda, sub-Stieda or para-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites are elongate, 12.8 9 2.9 lm in size, and contain anterior and posterior refractile bodies with a nucleus between them. This is the ninth species of coccidium described from skinks from PNG, and the new species described herein is apparently endemic to the skink genus Carlia (Gray).
We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, S... more We collected fecal samples from 9 dusky rice rats, Melanomys caliginosus (Rodentia, Cricetidae, Sigmodontinae), in a Biological Reserve in Costa Rica and found 8 (89%) to be infected with 2 Eimeria species which we describe here as new. Sporulated oocysts (n ¼ 20) of the first, Eimeria melanomytis n. sp., are cylindroidal and measure 20.1 3 13.3 lm (18-23 3 13-15); micropyle and oocyst residuum are both absent, but a bilobular polar granule is present. Its sporocysts are ovoidal, 10.5 3 7.4 lm (10-13 3 6-8) with a small Stieda body, but both substieda and parastieda bodies are absent; a spheroidal sporocyst residuum is present,~5 lm wide. Sporulated oocysts (n ¼ 20) of the second, Eimeria rebambensis n. sp., are subspheroidal, 21.2 3 17.0 lm (19-23 3 14-18); micropyle and oocyst residuum are both absent, but with a polar granule~2 lm wide. Sporocysts are elongate-ovoidal, 12.4 3 7.0 lm (11-14 3 6-9) with a distinct knob-like Stieda body, and a substieda body directly beneath it which is about twice as wide, but no parastieda body is present; the sporocyst residuum is an irregular mass composed of 8-10 globules scattered among the sporozoites, which are~10 3 5 lm, and have 1 refractile body at their wider end and a central nucleus. These are the first eimerians described from this rodent genus.
... 1998. Development of Alouattamyia baeri (Diptera: Oestridae) from howler monkeys (Primates: C... more ... 1998. Development of Alouattamyia baeri (Diptera: Oestridae) from howler monkeys (Primates: Cebidae) on Barro Colorado Island, Panama. J. Med. Entomol. 35: 674-680. Daniel, WW 1984. Bioestadistica: Base para el an~lisis de las ciencias de la salud. ...
We propose the first molecular systematic hypothesis for the origin and evolution of Cebus capuci... more We propose the first molecular systematic hypothesis for the origin and evolution of Cebus capucinus based on an analysis of 710 base pairs (bp) of the cytochrome c oxidase subunit II (COII) mitochondrial gene in 121 C. capucinus specimens sampled in the wild. The animals came from the borders of Guatemala and Belize, Costa Rica, and eight different departments of Colombia (Antioquia, Chocó, Sucre, Bolivar, Córdoba, Magdalena, Cauca, and Valle del Cauca). Three different and significant haplotype lineages were found in Colombia living sympatrically in the same departments. They all presented high levels of gene diversity but the third Colombian gene pool was determined likely to be the most ancestral lineage. The second Colombian mitochondrial (mt) haplogroup is likely the source of origin of the unique Central America mt haplogroup that was detected. Our molecular population genetics data do not agree with the existence of two well-defined subspecies in Central America (limitaneus and imitator). This Central America mt haplogroup showed significantly less genetic diversity than the Colombian mt haplogroups. All the C. capucinus analyzed showed evidence of historical population expansions. The temporal splits among these four C. capucinus lineages were related to the completion of the Panamanian land bridge as well as to climatic changes during the Quaternary Period.
Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studi... more Fecal samples of 53 white face monkeys (Cebus capucinus) from some sites of Costa Rica were studied for blood and intestinal parasites. Animals were anesthetized with darts containing Telazol, blood and fecal samples were collected and all the material was studied in the laboratory. For blood parasites, Giemsa stain and Knott concentration was performed. Intestinal parasites were studied by direct examination in 0,85% saline solution and a Iodine solution. Haematoxylin stain was used for better protozoa identification. Strongyloides sp, hookworms, acanthocephalid eggs and other nematodes, as well as Tritrichomonas sp (more frequent) and other protozoa were found. The presence of at least one parasites was observed in 33.3% to 100% of the fecal samples with an average of 73.6%. There was not any correlation between sex and infection rate, but the presence of parasite was higher in heavier (older) animals. Microfilarias were the only blood organism detected.The reasons for these high infection rates could be explained for feed diversity, contaminated soil and water contact and sociability of these animals, among other factors.
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