RESUMO
Leptospires are widespread spirochete bacteria that infect mammals, including rodents and humans. We investigated the presence of Leptospira antibodies in two species of rodents from San Pedro River Basin (SPRB) in northwestern Mexico as part of the black-tailed prairie dog ( Cynomys ludovicianus ) monitoring plan and the North American beaver ( Castor canadensis ) reintroduction program. We sampled a total of 26 black-tailed prairie dogs and three beavers during October-November 2015. We detected antibodies against Leptospira spp. by microagglutination test in 12 (46%) prairie dogs and in two (67%) beavers. The antibody titers for seropositive rodents varied from 1:100 to 1:200, but none of the animals showed clinical signs of disease. We found seven Leptospira spp. serogroups (Autumnalis, Australis, Bataviae, Canicola, Celledoni, Grippotyphosa, and Sejroe) circulating in rodent species in SPRB. We did not find any differences between sex and age concerning Leptospira-positive rodents. Our findings suggest the presence of endemic cycles and potential risks of Leptospira infection in both species from SPRB. Although the impact of this infection on threatened species remains unclear, human activities and environmental stress might facilitate the emergence or reemergence of leptospirosis disease as has been reported elsewhere.
Assuntos
Leptospira/imunologia , Leptospirose/veterinária , Doenças dos Roedores/epidemiologia , Roedores , Sciuridae , Testes de Aglutinação/veterinária , Animais , Anticorpos Antibacterianos/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Leptospira/classificação , Leptospirose/epidemiologia , Leptospirose/imunologia , México/epidemiologia , Prevalência , Doenças dos Roedores/imunologiaRESUMO
BACKGROUND: The western burrowing owl (Athene cunicularia hypugaea) occurs throughout western North America in various habitats such as desert, short-grass prairie and shrub-steppe, among others, where the main threat for this species is habitat loss. Range-wide declines have prompted a need for reliable estimates of its populations in Mexico, where the size of resident and migratory populations remain unknown. RESULTS: Our objective was to estimate the abundance and density of breeding western burrowing owl populations in Mexican prairie dog (Cynomys mexicanus) colonies in two sites located within the Chihuahuan Desert ecoregion in the states of Nuevo Leon and San Luis Potosi, Mexico. Line transect surveys were conducted from February to April of 2010 and 2011. Fifty 60 ha transects were analyzed using distance sampling to estimate owl and Mexican prairie dog populations. We estimated a population of 2026 owls (95 % CI 1756-2336) in 2010 and 2015 owls (95 % CI 1573-2317) in 2011 across 50 Mexican prairie dog colonies (20,529 ha). CONCLUSIONS: The results represent the first systematic attempt to provide reliable evidence related to the size of the adult owl populations, within the largest and best preserved Mexican prairie dog colonies in Mexico.