Morphological and molecular characterization of Trichuris muris (Nematoda: Trichuridae): studies from two commensal rodent species

In this paper we re-describe Trichuris muris based on morphological data following isolation from two commensal rodent species, Mus musculus from Mexico and Rattus rattus from Argentina. Furthermore, we provide a molecular characterization based on mitochondrial (cytochrome c oxidase subunit 1 mitochondrial gene) and nuclear (internal transcribed spacer 2 region) markers in order to support the taxonomic identification of the studied specimens of T. muris from M. musculus. We distinguished T. muris from 29 species of Trichuris found in American rodents based on morphological and biometrical features, such as the presence of a spicular tube, length of spicule, size of proximal and distal cloacal tube and non-protrusive vulva. We suggest that spicular tube patterns can be used to classify Trichuris species in three groups. Considering that the diagnosis among the species of this genus is mainly based on morphometry, this proposal represents a relevant contribution. We provide molecular studies on two markers, making this the first contribution for T. muris in the Americas. This study makes an important contribution to the integrative taxonomy of cosmopolitan nematode species, and its correct determination from the parasitological study of commensal rodents.Fil: Panti May, Jesús Alonso. Universidad Autonoma de Yucatan (uady);Fil: Gómez Muñoz, María de Los Ángeles. Universidad Nacional del Nordeste; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Yeh Gorocica, A. B.. Universidad Autonoma de Yucatan (uady);Fil: Hernández Betancourt, S.. Universidad Autonoma de Yucatan (uady);Fil: Milano, F.. Universidad Nacional del Nordeste; ArgentinaFil: Galliari, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Robles, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentin

Population Characteristics of Human-Commensal Rodents Present in Households from Mérida, Yucatán, México

Anthropocommensal rodents live in close proximity to humans in many habitats around the world. They are a threat to public health because of the pathogens they carry. Recent studies in Mérida, Yucatán, México, have shown that commensal rodents harbor potential zoonotic pathogens such as bacteria, helminths, and viruses. In this study, we describe reproductive and demographic parameters of house mice and black rats present in households from Mérida, Yucatán, México, a municipality located in a tropical region in southern México. Rodents were trapped in 142 households within the municipality of Mérida from 2011 to 2014. A total of 832 rodents were trapped, constituting 556 (66.8%) house mice (Mus musculus) and 276 (33.2%) black rats (Rattus rattus). The sex ratio in mice was different than parity, while in rats it was 1:1. Mice in the weight class 8.1–12 g were most abundant in both females (52.9%) and males (57.2%). On the other hand, rats weighing ≤ 40 g (25% of females and 28.6% of males) were most abundant. The percentage of pregnancy in mice was 46.7%, whereas in rats it was 21.3%. The mean number of embryos was 4.7 and 5.8 in mice and rats, respectively. This study provides relevant demographic information on the ecology of commensal rodents from a tropical region of Latin America. We consider that our findings could be useful as a first step toward understanding the ecological behavior of rodent populations in tropical regions

Absence of molecular evidence of Leptospira spp. in urine samples collected from rodents captured in Yucatán, México

Leptospira spp. is a spirochete bacteria, causal agent of leptospirosis, zoonotic disease endemic in México that represents a serious public health and veterinary problem. Rodents are recognised as the most important reservoirs of this bacteria, which is transmitted mainly through direct or indirect contact with the Leptospira spp. excreted in the urine of infected individuals. Theaim of this study was to evaluate the circulation of Leptospira spp. in urine samples of wild and synanthropic rodents from Yucatán, México. Eighty-four rodents were captured in the community of Cenotillo, Yucatán. Twenty-six urine samples were collected from the bladder and were used in the total DNA extraction. The identification of Leptospira spp. was intended through the polymerase chain reaction test in its endpoint variant. No evidence of Leptospira spp. was found in the urine samples. It is necessary to use other tissues for the identification of Leptospira spp., before concluding that the rodents used in the present study are not reservoirs of this bacteri

Infección natural con Trypanosoma cruzi en murciélagos capturados en Campeche y Yucatán, México

Introduction: Bats have been reported as hosts of the Trypanosoma cruzi protozoan, the etiologic agent of American trypanosomiasis, an endemic zoonotic disease in México.Objective: To describe T. cruzi infection in bats from the states of Campeche and Yucatán, México.Materials and methods: Captures were made from March to November, 2017, at three sites in Yucatán and one in Campeche. Up to four mist nets on two consecutive nights were used for the capture. The bats’ species were identified and euthanasia was performed to collect kidney and heart samples for total DNA extraction. Trypanosoma cruzi infection was detected by conventional PCR with the amplification of a fragment belonging to the T. cruzi DNA nuclear.Results: Eighty-six bats belonging to five families (Vespertilionidae, Noctilionidae, Mormoopidae, Phyllostomidae, and Molossidae) and 13 species (Rhogeessa aeneus, Noctilio leporinus, Pteronotus davyi, P. parnellii, Artibeus jamaicensis, A. lituratus, A. phaeotis, Glossophaga soricina, Carollia sowelli, Chiroderma villosum, Uroderma bilobatum, Sturnira parvidens, and Molossus rufus) were captured. Infection frequency by PCR was 30,2% (26/86) detected only in the renal tissue. The infected species were P. parnellii, G. soricina, A. lituratus, A. jamaicensis, S. parvidens, C. villosum, and R. aeneus.Conclusions: Our results confirmed the participation of several bat species as hosts in the T. cruzi transmission cycle in the region. Further studies are necessary to establish the importance of these animals in the zoonotic transmission of T. cruzi.Introducción. Los murciélagos se han reportado como huéspedes del protozoario Trypanosoma cruzi, agente etiológico de la tripanosomiasis americana, enfermedad zoonótica endémica en México.Objetivo. Describir la infección con T. cruzi en murciélagos capturados en los estados de Campeche y Yucatán, México.Materiales y métodos. Se realizaron capturas de marzo a noviembre de 2017 en tres sitios de Yucatán y uno de Campeche. Para la captura se emplearon hasta cuatro redes de niebla por dos noches consecutivas. Se identificó la especie de los murciélagos capturados y se les practicó la eutanasia para recolectar muestras de riñón y corazón, utilizadas posteriormente en la extracción de ADN total. La infección con T. cruzi se detectó por la amplificación con PCR convencional de un fragmento perteneciente al ADN nuclear de T. cruzi.Resultados. Se capturaron 86 murciélagos pertenecientes a cinco familias (Vespertilionidae, Noctilionidae, Mormoopidae, Phyllostomidae, Molossidae) y 13 especies (Rhogeessa aeneus, Noctilio leporinus, Pteronotus davyi, P. parnellii, Artibeus jamaicensis, A. lituratus, A. phaeotis, Glossophaga soricina, Carollia sowelli, Chiroderma villosum, Uroderma bilobatum, Sturnira parvidens y Molossus rufus). La PCR mostró una frecuencia de infección de 30,2 % (26/86), detectada únicamente en tejido renal. Las especies infectadas fueron P. parnellii, G. soricina, A. lituratus, A. jamaicensis, S. parvidens, C. villosum y R. aeneus.Conclusiones. Los resultados confirmaron la participación de varias especies de murciélagos como huéspedes en el ciclo de transmisión de T. cruzi en la región. Es necesario realizar más estudios para determinar la importancia de estos animales en la transmisión zoonótica de T. cruzi

A Two-Year Ecological Study of Norway Rats (Rattus norvegicus) in a Brazilian Urban Slum

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2016-07-25T15:57:03Z No. of bitstreams: 1 Panti-May JA A two year ecological....pdf: 316403 bytes, checksum: 4e80356daf5df2ea98e386b764daa8b9 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2016-07-25T16:23:03Z (GMT) No. of bitstreams: 1 Panti-May JA A two year ecological....pdf: 316403 bytes, checksum: 4e80356daf5df2ea98e386b764daa8b9 (MD5)Made available in DSpace on 2016-07-25T16:23:03Z (GMT). No. of bitstreams: 1 Panti-May JA A two year ecological....pdf: 316403 bytes, checksum: 4e80356daf5df2ea98e386b764daa8b9 (MD5) Previous issue date: 2016Fundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / University of Liverpool. Institute of Integrative Biology. Liverpool, United KingdomFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversity of Liverpool. Institute of Integrative Biology. Liverpool, United KingdomFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilMinistério da Saúde. Secretaria Municipal de Saúde. Centro de Controle de Zoonoses. Salvador, BA, BrasilFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / Yale School of Public Health. Department of Epidemiology of Microbial Diseases. New Haven, Connecticut, USAFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / Yale School of Public Health. Department of Epidemiology of Microbial Diseases. New Haven, Connecticut, USAYale School of Public Health. Department of Epidemiology of Microbial Diseases. New Haven, Connecticut, USAUniversity of Liverpool. Institute of Integrative Biology. Liverpool, United KingdomFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / University of Liverpool. Institute of Integrative Biology. Liverpool, United Kingdom / Yale School of Public Health. Department of Epidemiology of Microbial Diseases. New Haven, Connecticut, USA / Universidade Federal da Bahia. Instituto de Saúde Coletiva. Salvador, BA, BrasilThe Norway or brown rat (Rattus norvegicus) is among the most ubiquitous of rodents. However, the lack of studies describing Norway rat populations from tropical areas have limited our understanding regarding their demography and seasonal dynamics. In this study, we describe seasonal pattern in the abundance, reproductive parameters, and morphometrics of Norway rat populations in Salvador, Brazil. Rodents were trapped over four seasonal trapping periods (2013-2014) from three valleys. A total of 802 Norway rats were trapped over the course of the study over 7653 trap-nights. Norway rat abundance was high, but there was no significant differences between seasons. The reproductive parameters (e.g. frequency of pregnant and lactating females) did not show statistical differences between seasons. Female rats collected in the rainy season were heavier and older than females from the dry season. Salvador rats had a high incidence of pregnancy and birth rate (estimated birth rate of 79 young per year) compared to previous studies. The information generated is critical for the understanding of the ecology of Norway rat, the main reservoir of Leptospira in Salvador. However, future studies examining the effect of rodent control programs aimed at reducing populations, and determining rates of recovery, will further clarify our understanding of population dynamics

Summary of population characteristics of Norway rats for comparison between seasons in Salvador, Brazil.

<p>Summary of population characteristics of Norway rats for comparison between seasons in Salvador, Brazil.</p

Seasonal comparison of age (<i>above</i>) and mass (<i>below</i>) classes for male and female Norway rats from Salvador, Brazil.

<p>Black bars for rainy season and white bars for dry season. Statistical differences were found in age and mass structure of females between seasons (P < 0.05).</p