Volumen y Número: En prensa Vol. 31 Nº 1

Para discriminar a qué futuro número pertenecerá cada artículo en prensa (o manuscrito aceptado).

Intestinal helminth community structure of white-eared opossum (Didelphis albiventris) that inhabit rural areas of Buenos Aires, Argentina

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The white-eared opossum (Didelphis albiventris) is a neotropical marsupial that inhabits various ecoregions and highly modified environments. However, there is limited research on host-parasite interactions and the structure of helminth communities in D. albiventris. Therefore, the aim of this study is to investigate the intestinal helminths of D. albiventris inhabiting a rural area in Buenos Aires, Argentina, and assess the relationship between host age and sex, and helminth community structure. Opposums were captured in 2004 and intestines were examined to detect helminths. By analyzing 22 intestines, we identified a total of 8978 helminths, including Cruzia tentaculata, Turgida turgida, Rhopalias coronatus, Brachylaima sp., individuals of the Family Diplostomidae, and a single specimen of a cestode. Among these, C. tentaculata and R. coronatus were the most prevalent species, with C. tentaculata exhibiting the higher levels of abundance, mean intensity, and aggregation index. To assess the influence of host sex and age on parasite abundance and probability of occurrence, we conducted Generalized Linear Models. The results revealed that host juveniles had lower helminth prevalence and abundance compared to other age categories. Host sex was only significant in interaction with host age for parasite abundance of C. tentaculata and R. coronatus. Most captured juveniles relied on maternal feeding, potentially reducing exposure to consuming infected intermediate hosts with indirect life cycles. Understanding the parasite ecology of this opossum species in modified environments provides valuable information about their role at the wildlife-human interface in anthropogenic areas.

Estructura de la comunidad helmíntica intestinal de las comadrejas overas (Didelphis albiventris) que habitan áreas rurales de Buenos Aires, Argentina. La comadreja overa Didelphis albiventris es un marsupial neotropical que habita en diversas ecorregiones, hallándose frecuentemente en ambientes peridomésticos. Si bien existen trabajos que describen los parásitos de D. albiventris, los estudios que contemplan asociaciones entre estos y las características intrínsecas del hospedador son escasos. El objetivo de este estudio fue describir los helmintos intestinales de Didelphis albiventris en un área rural de Buenos Aires, y evaluar la influencia del sexo y la edad del hospedador sobre la presencia y abundancia de parásitos. Se analizaron 22 intestinos provenientes de la captura de ejemplares de D. albiventris y se realizaron Modelos Lineales Generalizados. Se hallaron 8978 helmintos: Cruzia tentaculata, Turgida turgida, Rhopalias coronatus, Brachylaima sp.; Familia Diplostomidae y un cestode. Cruzia tentaculata y R. coronatus fueron las especies más prevalentes, presentando C. tentaculata mayor abundancia, intensidad media e índice de agregación. Los helmintos hallados son heteroxenos y fueron registrados previamente para esta especie. Los resultados indican que los juveniles poseen menor presencia y abundancia de helmintos, lo cual estaría asociado su modo de alimentación. El sexo sólo fue significativo en interacción con la edad para la abundancia de C. tentaculata y R. coronatus. Estudiar la estructura de la comunidad parasitaria de D. albiventris y los factores que la determinan proporciona información sobre su rol en el ambiente, particularmente en ambientes modificados donde la interacción fauna silvestre-humanos es mayor. Futuros estudios que contemplen características ambientales y tamaño corporal del hospedador complementarán los resultados hallados en este trabajo.

Rickettsia spp. seroprevalence in wild mammals from Arauca, Orinoquia region of Colombia

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Rickettsia includes pathogenic bacteria that commonly use mammals as reservoirs and amplifying hosts. In Colombia, the knowledge about mammals as reservoirs of these bacteria is limited, even in areas considered as endemic regions for spotted fever group (SFG) rickettsiae. To identify wild mammals acting as potential reservoirs of Rickettsia spp., we collected blood from 573 individuals captured in the Orinoquia of Colombia and processed to obtain serum (n = 351) and DNA (n = 250). The serum was evaluated using indirect immunofluorescence assays (IFA) for the detection of IgG antibodies to four SFG rickettsiae antigens (Rickettsia rickettsii, R. parkeri, R. amblyommatis, R. rhipicephali), and R. bellii of the Ancestral group (AG). We amplified a fragment of the rickettsial citrate synthase gene (gltA) to detect Rickettsia from blood samples. The IFA showed seropositivity in 122 individuals of 20 mammalian species. IgG antibodies titers to Rickettsia spp., at a cutoff of ≥ 1:64, were 70.49% in bats (n = 86), 21.31% rodents (n = 26); 7.38% marsupials (n = 9), and 0.82% carnivores (n = 1). The possible antigen involved in a homologous reaction (PAIHR) was R. belli (18.85%), R. amblyommatis (9.01%), R. rhipicephali (4.91%), R. rickettsia (4.91), and R. parkeri (4.09%), respectively. Bats were the most seropositive hosts with the presence of antibodies to different Rickettsia antigens. We detected Rickettsia in 2.8% of the DNA samples (n = 5) from rodents, bats, and marsupials, but we could not confirm the molecular identity of Rickettsia. The presence of antibodies indicated a possible exposure of the evaluated mammals to SFG and AG rickettsiae and support that the Orinoco Region must be considered endemic for SFG rickettsiae.

Seroprevalencia de Rickettsia spp. en mamíferos silvestres de Arauca, región de la Orinoquia de Colombia. Rickettsia incluye bacterias patógenas que comúnmente utilizan mamíferos como reservorios y hospedadores amplificadores. En Colombia el conocimiento sobre mamíferos reservorios de estas bacterias es limitado, incluso en áreas consideradas endémicas para Rickettsia del grupo de las fiebres maculosas (SFG). Para identificar mamíferos silvestres que actúan como reservorios potenciales de Rickettsia spp., recolectamos muestras de sangre de 573 individuos capturados en la Orinoquia de Colombia y procesamos para obtener suero (n = 351) y ADN (n = 250). El suero se evaluó mediante ensayos de inmunofluorescencia indirecta (IFA) para la detección de anticuerpos IgG contra cuatro antígenos de rickettsias SFG (Rickettsia rickettsii, R. parkeri, R. amblyommatis, R. rhipicephali) y R. bellii del grupo Ancestral (AG). Además, amplificamos un fragmento del gen rickettsial citrato sintasa (gltA) para detectar Rickettsia spp. a partir de muestras de sangre entera. Los resultados de IFA mostraron seropositividad en 122 individuos de 20 especies de mamíferos. Los títulos de anticuerpos IgG contra Rickettsia spp., en un punto de corte de ≥ 1:64, fueron 70,49% en murciélagos (n = 86), 21,31% en roedores (n = 26); 7,38 % marsupiales (n = 9), y 0,82% carnívoros (n = 1). El posible antígeno implicado en una reacción homóloga (PAIHR) fue R. belli (18,85%), R. amblyommatis (9,01%), R. rhipicephali (4,91%), R. rickettsia (4,91), y R. parkeri (4,09%), respectivamente. Los murciélagos fueron los hospedadores más seropositivos con presencia de anticuerpos contra diferentes antígenos de Rickettsia. Detectamos Rickettsia en el 2,8% de las muestras de ADN (n = 5) de roedores, murciélagos y marsupiales, pero no fue posible confirmar la identidad molecular de las Rickettsia. La presencia de anticuerpos indica una posible exposición de los mamíferos evaluados a las rickettsias SFG y AG, y la Orinoquía debe ser considerada endémica para rickettsiae SFG.

Review of tick species in two small synanthropic mammals, Didelphis albiventris (Lund, 1840) and Rattus rattus (Linnaeus, 1758)

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The present study aims to make a literature review, for the years between 1960 and 2022, of tick species that affect two species of small synanthropic mammals. A literature review was carried out on the ticks that affect the species Didelphis albiventris (Lund, 1840) and Rattus rattus (Linnaeus, 1758), covering the years 1960 to 2022. The main countries that contributed to studies on the subject were: Brazil (N = 48), corresponding to 84% of the articles found. Then by Argentina, Angola, Madagascar, Sri Lanka, Australia, Italy, Singapore, United States, and Taiwan, each contributing with one article (N = 1), representing 2% each of the articles found, totaling 16% remaining. We also observed differences between the percentages of studies on the small mammal species surveyed, with 77% carried out with the species D. albiventris, and 23% referring to R. rattus. Considering only the studies carried out in Brazil, which corresponded to 84%, Atlantic Forest and Cerrado seem to be the biomes with the most published studies, with ticks for both host species (N = 34) 47% and (N = 30) 42%, respectively. Therefore, 7% (N = 5) of the studies were found for the Caatinga biome, and 4% (N = 3) for the Pampa biome.

Espécies de carrapatos em dois pequenos mamíferos sinantrópicos. O presente estudo tem como objetivo fazer uma revisão de literatura, para os anos de 1960 a 2022, das espécies de carrapatos que acometem duas espécies de pequenos mamíferos sinantrópicos. Foi realizada revisão da literatura sobre os carrapatos que acometem as espécies Didelphis albiventris (Lund, 1840) e Rattus rattus (Linnaeus, 1758), abrangendo os anos de 1960 a 2022. Os principais países que contribuíram com estudos sobre o tema foram: Brasil (N = 48), correspondendo a 84% dos artigos encontrados; depois por Argentina, Angola, Madagascar, Sri Lanka, Austrália, Itália, Cingapura, Estados Unidos e Taiwan, cada um contribuindo com um artigo (N = 1), representando 2% cada um dos artigos encontrados, totalizando 16% restantes. Também observamos diferenças entre os percentuais de estudos sobre as espécies de pequenos mamíferos pesquisadas, com 77% realizados com a espécie D. albiventris, e 23% referentes a R. rattus. Considerando apenas os estudos realizados no Brasil, que corresponderam a 84%, Mata Atlântica e Cerrado parecem ser os biomas com mais estudos publicados, com carrapatos para ambas as espécies hospedeiras (N = 34) 47% e (N = 30) 42 %, respectivamente. Portanto, 7% (N = 5) dos estudos foram encontrados para o bioma Caatinga e 4% (N = 3) para o bioma Pampa.

Evidences of non-lethal rabies virus exposure in free-ranging wild carnivores from Brazilian Pampa

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Rabies virus (RABV) may infect wildlife, domestic mammals and humans worldwide, and outbreaks have been associated with population declines of wild carnivores. Although RABV infection has been considered almost invariably fatal, there has been growing evidence of non-lethal RABV exposure in wildlife. The aim of this study is to investigate the occurrence of RABV antibodies, as evidence of non-lethal exposure to virus in free-living wild canids and felids from the Brazilian Pampa. Animals were live-trapped in three protected and two unprotected areas from Southern Brazil, and the presence of antibodies against RABV was verified by RFFIT test. A total of 98 specimens without clinical signs of disease were live-trapped: 35 Cerdocyon thous, 23 Lycalopex gymnocercus, 29 Leopardus geoffroyi, 11 Leopardus wiedii. Thirteen out of 98 wild carnivores were considered seropositives to RABV: five C. thous, one L. gymnocercus, five L. geoffroyi and two L. wiedii. All five localities where animals were sampled had at least one seropositive individual. The results support previous conclusions regarding the possible involvement of C. thous in the rabies ecology, and expand the findings of RABV-seropositivity in free-living wildlife, representing the first record for the following species: L. gymnocercus, L. geoffroyi and L. wiedii. Our findings also suggest that RABV circulation and non-lethal exposure in Neotropical wild carnivores may be more common than previously assumed. Furthermore, rabies and its sylvatic cycle should be taken into account in any conservation effort for wild carnivores.

Evidências de exposição não-letal ao vírus da raiva em carnívoros silvestres de vida livre no Pampa brasileiro. O vírus da raiva (RABV) pode infectar mamíferos silvestres, domésticos e humanos em todo o mundo, e surtos têm sido associados com declínios populacionais em carnívoros silvestres. Apesar da infecção pelo RABV ser considerada invariavelmente fatal, há evidências crescentes de exposição não-letal em animais silvestres. O objetivo deste trabalho é investigar a ocorrência de anticorpos contra RABV, como evidência de exposição não-letal ao vírus em canídeos e felídeos de vida livre no Pampa brasileiro. Os animais foram capturados em três áreas de preservação e duas áreas não-protegidas do Sul do Brasil, e a presença de anticorpos contra RABV foi verificada por RFFIT. Um total de 98 espécimes sem sinais de doença foram capturados: 35 Cerdocyon thous, 23 Lycalopex gymnocercus, 29 Leopardus geoffroyi e 11 Leopardus wiedii. Treze dos 98 carnívoros silvestres foram considerados soropositivos para RABV: cinco C. thous, um L. gymnocercus, cinco L. geoffroyi, e dois L. wiedii. Todas as cinco localidades onde os animais foram amostrados apresentaram ao menos um indivíduo soropositivo. Os resultados corroboram conclusões anteriores sobre o possível envolvimento de C. thous na ecologia da raiva, e expandem os achados de soropositividade para RABV em animais silvestres, representando o primeiro registro para as seguintes espécies: L. gymnocercus, L. geoffroyi e L. wiedii. Nossos resultados também sugerem que a circulação do RABV e a exposição não-letal em carnívoros silvestres neotropicais pode ser mais comum do que previamente assumido. Outrossim, a raiva e seu ciclo silvestre devem ser levados em consideração em qualquer esforço de conservação de carnívoros silvestres.

Nematodes parásitos en epidídimos de dos especies del género Sturnira (Chiroptera: Phyllostomidae): ¿transmisión sexual de nematodes en murciélagos?

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Los murciélagos juegan un importante rol en la salud pública. Su capacidad de volar, la diversidad de hábitats que ocupan, su comportamiento social de vivir en grandes colonias o en pequeños grupos, su diversidad trófica y las posibles interacciones con los humanos facilitan la transmisión y propagación de diferentes patógenos. A pesar de esto y de la amplia variedad de parásitos que albergan, se conoce muy poco sobre su fauna parasitaria, los ciclos de vida, los modos de transmisión y menos aún como influyen sobre la reproducción y la supervivencia del hospedador. El objetivo del presente trabajo es reportar por primera vez larvas de nematodes en el epidídimo de los murciélagos frugívoros Sturnira erythromos y Sturnira lilium, y analizar una posible transmisión sexual de macroparásitos. Se analizaron a nivel histológico los tractos reproductores y las gónadas de 272 murciélagos de diferentes localidades del noroeste de Argentina. En los epidídimos de siete machos de S. erythromos y uno de S. lilium observamos parásitos, que por sus dimensiones se identificaron como larvas, y por la presencia de una estructura interna similar a esticosomas se cree que podrían ser de la Superfamilia Trichinelloidea. Si bien esto no es prueba suficiente de una transmisión sexual, no descartamos esta posibilidad; creemos que aún faltan más estudios para probar que las larvas efectivamente pasan a través de la eyaculación al tracto reproductor femenino, desde donde luego migrarían para colonizar otros órganos.

Parasitic nematodes in epididymima of two species of the genus Sturnira (Chiroptera: Phyllostomidae): sexual transmission of nematodes in bats? Bats play an important role in public health. Their ability to fly, the diversity of habitats they occupy, their social behavior of living in large colonies or small groups, their trophic diversity, and possible interactions with humans facilitate the transmission and spread of different pathogens. Despite this and the wide variety of parasites they harbor, very little is known about their parasitic fauna, life cycles, modes of transmission, and even less about how they influence host reproduction and survival. The objective of this work is to report for the first time nematode larvae in the epididymis of the frugivorous bats Sturnira erythromos and Sturnira lilium, and to analyze a possible sexual transmission of macroparasites. The reproductive tracts and gonads of 272 bats from different locations in northwestern Argentina were histologically analyzed. In the epididymis of seven males of S. erythromos and one of S. lilium, we observed parasites, which due to their dimensions were identified as larvae, and due to the presence of an internal structure similar to sticosomes, it is believed that they could be from the Superfamily Trichinelloidea. Although this is not sufficient proof of sexual transmission, we do not rule out this possibility; we believe that more studies are still needed to prove that the larvae actually pass through the ejaculation to the female reproductive tract, from where they would later migrate to colonize other organs.

Domestic dogs as host of ectoparasites carrying Rickettsia, Bartonella and Mycoplasma in urban, peri-urban and rural areas from center Argentina

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Domestic dog (Canis lupus familiaris) plays a vital role in transmitting zoonotic ectoparasites and vector-borne pathogens, often being an important source of pathogens in spill over and spillback processes between domestic and wild animals. The aim of this study was analyzing the diversity and prevalence of ectoparasites and their associated bacteria, Rickettsia, Bartonella and Mycoplasma, in dogs from urban, peri-urban and rural environments, from central Argentina. A total of 180 dogs were examined, and 308 ectoparasites were collected. Diversity and prevalence (P) for environment were: Urban (Ptotal = 78%) [Ctenocephalides felis felis (P = 78.1%); Rickettsia felis (P = 25%); Bartonella sp. (P = 8.3%); Mycoplasma suis (P = 8.3%)]; Peri-urban (Ptotal = 83%) [C. felis felis (P = 80%); Rhipicephalus sanguineus s. l. (P = 20%); R. felis (P = 19.2%); Bartonella sp. (P = 25%); M. suis (P = 3.8%)]; Rural (Ptotal = 50%) [Pulex irritans (P = 45.4%); R. sanguineus s. l. (P = 15.1%); R. felis (P = 7.4%); M. suis (P = 8.7%)]. These results present new insights into bacteria distribution across environments, emphasizing the role of dogs in their circulation. Pulex irritans, flea with the highest prevalence in foxes, exclusively found in the rural environment, supports the hypothesis that wild and domestic sympatric carnivores share ectoparasite species. The detection of M. suis for the first time in all analyzed ectoparasite species and environments raises questions regarding the potential reservoir role of dogs for this pathogen. Furthermore, it suggests that dogs infested with ectoparasites may be exposed to an unknown range of potentially invasive vector-borne pathogens. These findings reinforce the importance of parasitological and epidemiological studies in domestic mammals under the “One Health” paradigm.

Perros domésticos como hospedadores de ectoparásitos portadores de bacterias Rickettsia, Bartonella y Mycoplasma en áreas urbanas, peri-urbanas y rurales del centro de Argentina. El perro doméstico (Canis lupus familiaris) desempeña un papel fundamental en la transmisión de ectoparásitos y patógenos transmitidos por vectores, siendo muchas veces una fuente importante en el proceso de traspaso de patógenos entre animales silvestres y domésticos. El objetivo fue analizar la diversidad y prevalencia de ectoparásitos y bacterias de los géneros Rickettsia, Bartonella y Mycoplasma en perros provenientes de ambientes urbanos, peri-urbanos y rurales del centro de Argentina. Se examinaron 180 perros, recolectándose 308 ectoparásitos. La diversidad y prevalencia (P) por ambiente fue: Urbano (Ptotal = 78%) [Ctenocephalides felis felis (P = 78,1%); Rickettsia felis (P = 25%); Bartonella sp. (P = 8,3%); Mycoplasma suis (P = 8,3%)]; Periurbano (Ptotal = 83%) [C. felis felis (P = 80%); Rhipicephalus sanguineus s. l. (P = 20%); R. felis (P = 19,2%); Bartonella sp. (P = 25%); M. suis (P = 3,8%)] y Rural (Ptotal = 50%) [Pulex irritans (P = 45,4%); R. sanguineus s. l. (P = 15,1%); R. felis (P = 17,4%); M. suis (P = 8,7%)]. Aportamos nueva información sobre la distribución de las bacterias en distintos ambientes, destacando el rol del perro para su circulación. La presencia exclusiva de Pulex irritans, pulga con mayor prevalencia en zorros, en el ambiente rural, refuerza la hipótesis de que carnívoros silvestres y domésticos simpátricos comparten especies de ectoparásitos. La detección de M. suis por primera vez, en todos los ambientes y especies ectoparásitas, plantea interrogantes sobre el papel potencial del perro como reservorio de este patógeno. Además, sugiere que los perros infestados con ectoparásitos pueden estar expuestos a una variedad desconocida de patógenos transmitidos por vectores. Estos resultados refuerzan la importancia de los estudios parasitológicos y epidemiológicos en mamíferos domésticos bajo el paradigma de «Una Salud».

Parásitos intestinales del piche (Zaedyus pichiy) en Malargüe, Mendoza: efecto de los factores ambientales y del hospedador

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El piche es un xenartro endémico del centro y sur de Argentina y Chile. El objetivo del presente trabajo fue describir los parásitos intestinales de una población de piches de Malargüe (Mendoza, Argentina) y evaluar qué factores (intrínsecos o extrínsecos) tienen mayor influencia sobre aquellos. Se estudiaron heces de 120 piches colectadas entre 2015 y 2016 mediante análisis coproparasitológicos, y se estimó la prevalencia total parasitaria. Se evaluó la influencia de factores intrínsecos del hospedador (sexo, edad y condición física) y extrínsecos (estacionalidad y año) sobre la dinámica de la estructura parasitaria usando modelos lineales generalizados (GLM). El 95% de las muestras estuvieron parasitadas. Se hallaron cuatro tipos diferentes de ooquistes de coccidios, huevos de Cestoda y de Nematoda (Aspidodera y dos morfotipos de Trichostrongylina). Coccidia sp. 2, Aspidodera spp. y Trichostrongylina morfotipo 2 (Tricho 2) fueron las más prevalentes. Los GLM indicaron que en invierno el parasitismo de los adultos de Z. pichiy por Trichostrongylina morfotipo 1 (Tricho 1) estuvo influenciado por la condición física de los hospedadores. Por otro lado, la prevalencia de Coccidia sp. 2 y Tricho 2 estuvo influenciada por el año. Para los individuos analizados en 2016 la prevalencia con Tricho 1 también estuvo afectada por la condición física, y la de Coccidia sp. 4 y Tricho 2 por la estacionalidad. La prevalencia de Tricho 2 en 2016 fue mayor en los juveniles que en los adultos y la prevalencia para ambas edades disminuyó durante el verano. Este estudio permitió conocer la parasitofauna y la sinergia de diferentes factores en la prevalencia de los parásitos en la población estudiada.

Intestinal parasites of pichis (Zaedyus pichiy) in Malargüe, Mendoza: effect of environmental and host factors. The pichi is an endemic xenarthran from central and southern of Argentina and Chile. The aim of the present work was to describe the intestinal parasites of a pichis population from Malargüe (Mendoza, Argentina), and to assess which factors (intrinsic or extrinsic) have a major influence on them. Feces from 120 pichis were collected between 2015 and 2016, studied by coproparasitological analysis and the total prevalence was estimated. By means of generalized linear models (GLM), the influence of intrinsic factors of the host (sex, age and physical condition) and extrinsic (seasonality and year) on the dynamics of the parasite structure was evaluated. Virtually all the samples were parasitized (95%). Four different types of coccidian oocysts, eggs of Cestoda and Nematoda (Aspidodera and two morphotypes of Trichostrongylina) were found. Coccidia sp. 2, Aspidodera spp. and Trichostrongylina morphotype 2 (Tricho 2) were the most prevalent. GLM indicated that in winter the parasitism in adults of Z. pichiy by Trichostrongylina morphotype 1 (Tricho 1) was influenced by the physical condition of the host. On the other hand, prevalence of Coccidia sp. 2 and Tricho 2 was influenced by the year. Regarding hosts analyzed in 2016, prevalence with Tricho 1 is also affected by physical condition, and that of Coccidia sp. 4 and Tricho 2 by seasonality. Prevalence of Tricho 2 in 2016 was higher in juveniles than in adults, and the prevalence for both ages decreased during the summer. This study allowed us to know the parasitic fauna and the synergy of different factors in the prevalence between parasites in the studied population.

Sigmodontinae rodents (Muroidea: Cricetidae) as hosts of Cestoda from Argentina

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In Argentina, parasitological studies in Cricetidae rodents have been carried out mainly on nematodes. However, some research has shown that cestodes are also common components of their parasitic assemblages. In this study, Sigmodontinae rodents (Cricetidae-Muroidea) from the Cuenca del Plata, Argentina are studied as hosts of cestodes. New host species, geographical areas and parasitic infection parameters are provided. A total of 1675 specimens from 28 species of rodents from 67 localities were sampled for cestodes. Five taxa of cestodes belonging to three families were identified, including 20 new geographical records. In addition, nine new host-parasite associations are reported. These records help us to increase our understanding of richness of cestodes in the region, providing a data base to evaluate the effect of intrinsic and extrinsic factors on ecological indicators such as prevalence, abundance, and host specificity, among others.

En Argentina, los estudios parasitológicos en roedores Cricetidae han sido principalmente de nematodes. Sin embargo, algunas investigaciones han demostrado que los cestodes son componentes comunes de sus ensambles parasitarios. Los roedores Sigmodontinae (Cricetidae-Muroidea) de la región de la Cuenca del Plata, Argentina son estudiados como hospedadores de cestodes. Se brindan nuevos registros hospedatorios y geográficos, y parámetros de infección parasitaria. Un total de 1675 especímenes pertenecientes a 28 especies de roedores, de 67 localidades, fueron examinados con el fin de hallar especímenes de cestodes. Se identificaron cinco taxones de cestodes pertenecientes a tres familias, incluyendo 20 nuevos registros geográficos. Además, se reportan nueve nuevas asociaciones parásito-hospedador. Estos registros nos ayudan a aumentar nuestra comprensión de la riqueza de los cestodes en la región, proporcionando una base de datos para evaluar el efecto de los factores intrínsecos y extrínsecos sobre los indicadores ecológicos tales como prevalencia, abundancia, especificidad hospedatoria, entre otros.