Laboratories that perform PCR on a routine basis need to count on reliable DNA isolation methods. In locations where supply of DNA extraction kits depends on importation, having an in-house protocol is desirable. This is also important for laboratories limited by budget constraints. We present a low-cost DNA isolation protocol that incorporates well-known techniques, but that we have adapted to various animal tissues. We tested this protocol on animal blood and muscle, and on cell suspension from skin swabs. The results were comparable, in terms of amount and quality of DNA, to those obtained with two other commercially available methods. DNA retrieved with this protocol has been successfully employed for Sanger sequencing of gene PCR products from animal tissues and blood, as well as for PCR-based diagnosis of chytrid fungus in amphibians and blood parasites in birds.

Despite intensive research during the last few decades, understanding of ecological and physiological factors related to haemosporidian infections in birds is still fragmentary. Since more model organisms are needed in order to understand these infections in the wild, we analysed avian haemosporidian infections in the rufous-collared sparrow (Zonotrichia capensis, Emberizidae) in a dry forest of the Ecuadorian Andes. Parasite diversity was screened using molecular and morphological approaches. By molecular diagnosis, we identified three linages that were phylogenetically placed in the context of molecular haemosporidian diversity and associated with a morphospecies. By microscopy, we identified five described morphospecies and one additional undescribed morphospecies. We found that avian haemosporidian prevalence on the study site was 76.3%. Additionally, we used a series of generalized linear models to explore the potential relationship of parasite prevalence and parasitaemia with a set of variables related to physiological and environmental conditions. Although our results revealed associations of haemosporidian infections with precipitation, age and sampling site, the models only explained a small fraction of the variation.

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