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The aim of this research was to detect rabies virus in peripheral tissues in captive vampires. Vampire bats were inoculated with 106 MICLD50 of homologous rabies virus. Bats displayed clinical signs of rabies beginning on d 8 until the 19th d post-inoculation (pi). Rabies virus antigens were found in the brain of all rabid bats. Viral RNA was detected in brain, salivary gland and tongue tissue by RT-PCR and nested PCR (nPCR). Viral genome was also detected in organs unrelated to the central nervous system. Rabies virus was not detected in saliva nor documented from any tissues without occurrence of viral antigens in the brain. Host humoral response was most pronounced via the induction of viral neutralizing antibodies (VNA) from d 8 to 20 pi, having a peak at d 14 with 0.9 IU. Antibody levels were variable, but tended to remain high after inoculation, showing significant differences to the negative control group (P=0.001). This research is one of the few recent studies focused upon Desmodus rotundus and contributes to the basic knowledge of rabies virus pathogenesis, which is required for an understanding of perpetuation in a major viral reservoir in Latin America.

Palabras clave: Vampyrum spectrum, murciélagos, Chiroptera, Selva Lacandona, Chiapas.

Resumen:En el presente trabajo se presentan las relaciones entre dieta y demografía de dos especies de roedores (Reithrodontomys fulvescens y Peromyscus aztecus) en un bosque mesófilo de montaña y en un área perturbada del occidente de México. La información se obtuvo mediante técnicas de captura-recaptura. Las especies difirieron en la densidad poblacional, abundancia y en el tiempo de reproducción. La actividad reproductiva de P. aztecus en bosque mesófilo alcanzó sus máximos valores a mitad de la estación lluviosa y en a mitad de la estación seca-fría en el área perturbada. R. fulvescens registró la mayor actividad reproductiva en la estación húmeda en ambos hábitats. La densidad de P. aztecus mantuvo fluctuaciones a lo largo de todo el año, con picos en los meses de enero y febrero. R. fulvescens mostró el mismo patrón de densidad en ambos hábitats con lo máximos valores al final de la estación húmeda. Los hábitos alimentarios y la sobreposición de la dieta fueron evaluados mediante técnicas microhistológicas. La dieta de P. aztecus en bosque mesófilo estuvo dominada por frutos de Solanaceae, Melastomataceae, Araliaceae y Myrsinaceae. Dicotiledóneas (hojas y tallos), semillas de monocotiledóneas (Zea diploperennis) y de dicotiledóneas (Lupinus y Acacia) dominaron la dieta en R. fulvescens. Los valores más altos de sobreposición de la dieta en bosque mesófilo ocurrieron en la estación húmeda (77.6%) y el valor menor en la estación seca-caliente (25.1%). Las características nutrimentales de la dieta mostraron variación estacional. No existió una relación evidente entre los diferentes nutrimentos y la reproducción.Abstract: The relationship between diet and demography of two rodents (Reithrodontomys fulvescens and Peromyscus aztecus) in clouded forest and disturbed area of western Mexico was described. A live-traps study was conducted to obtain information about population dynamics. Species varied in population density, relative abundance, and reproduction timing, which was seasonal. Reproductive activity for P. aztecus peaked in the middle of the wet season in the clouded forest and in the wet season and middle of the dry-cold season indisturbed areas. R. fulvescens showed reproductive activity in the wet season in both habitats. Density fluctuated annually for P. aztecus in both habitats, with a peak in January - February;R. fulvescens showed the same patterns of density in both habitats with the highest values at the end of the wet season. Food habits and dietary overlap were evaluated by microhistological techniques. The diet of P. aztecus in the clouded forest was dominated by dicot fruits of Solanaceae, Melastomataceae, Araliaceae, and Myrsinaceae species. In disturbed area this species did not prefer a particular food item. Dicots (leaves and stems) dominated the diet, but seeds of monocots (Zea diploperennis) and dicots (Lupinus and Acacia) were also included. Reithrodontomys fulvescens consumed dicots species (seeds, fruits, leaves and stems). The greatest dietary overlap between species occurred in cloud forest during the wet season (77.6%), with less overlap in the dry-hot season (35.2 %). High overlap occurred in disturbed area during the wet season (68.2 %) and low values in the dry-hot season (25.1 %). Nutritional characteristics of diets showed seasonal variation.Palabras clave: Peromyscus aztecus, Reithrodontomys fulvescens, ecología poblacional, hábitos alimentarios, reproducción, occidente de México.