Phylogeography and Pleistocene demographic history of the endangered marsh deer (Blastocerus dichotomus) from the Rio de la Plata Basin

The marsh deer is the largest neotropical cervid with morphological and ecological adaptations to wetlands and riparian habitats. Historically, this now endangered species occupied habitats along the major river basins in South America, ranging from southern Amazonia into northern Argentina to the Parana river delta. This particularly close association with wetlands makes marsh deer an excellent species for studying the effects of Pleistocene climatic changes on their demographic and phylogeographic patterns. We examined mitochondrial DNA variation in 127 marsh deer from 4 areas distributed throughout the Rio de]a Plata basin. We found 17 haplotypes in marsh deer from Brazil, Bolivia and Argentina that differed by 1-8 substitutions in a 601 bp fragment of mitochondrial control region sequence, and 486 bp of cytochrome b revealed only 3 variable sites that defined 4 haplotypes. Phylogeny and distribution of control region haplotypes suggest that populations close to the Pantanal area in central Brazil underwent a rapid population expansion and that this occurred approximately 28,000-25,000 years BP. Paleoclimatic data from this period suggests that there was a dramatic increase for precipitation in the medium latitudes in South America and these conditions may have fostered marsh deer's population growth.

Genetic diversity of two Brazilian populations of the Pampas deer (Ozotoceros bezoarticus, Linnaeus 1758)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ocorrência e caracterização molecular de Cryptosporidium em cordeiros

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A leukocyte cryopreservation technique for cytogenetic studies

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conservation genetics of the endangered Pampas deer (Ozotoceros bezoarticus)

The Pampas deer (Ozotoceros bezoarticus L. 1758) is the most endangered neotropical cervid, and in the past occupied a wide range of open habitats including grassland, pampas, savanna, and cerrado (Brazil) from 5 degrees to 41 degrees S. To better understand the effect of habitat fragmentation on gene flow and genetic variation, and to uncover genetic units for conservation, we examined DNA sequences from the mitochondrial control region of 54 individuals from six localities distributed throughout the present geographical range of the Pampas deer. Our results suggest that the control region of the Pampas deer is one of the most polymorphic of any mammal. This remarkably high variability probably reflects large historic population sizes of millions of individuals in contrast to numbers of fewer than 80 000 today. Gene flow between populations is generally close to one migrant per generation and, with the exception of two populations from Argentina, all populations are significantly differentiated. The degree of gene flow was correlated with geographical distance between populations, a result consistent with limited dispersal being the primary determinant of genetic differentiation between populations. The molecular genetic results provide a mandate for habitat restoration and reintroduction of Pampas deer so that levels of genetic variation can be preserved and historic patterns of abundance can be reconstructed. However, the source of individuals for reintroduction generally should be from populations geographically closest to those now in danger of extinction.

Morfologia do estômago do cervo-do-pantanal (Blastocerus dichotomus, Illiger 1815)

Based on the lack of information regarding the morphology of marsh deer, this work aims to describe some morphological aspects of the gastric chamber in this species, collaborating with future investigations, mainly related to rational handling in this cervid. This work aimed to describe the morphology of the gastric chamber of the marsh deer, characterizing the external and internal macroscopical details and the microscopical architecture of these structures by light microscopy. Macroscopically, the marsh deer stomach is formed by the rumen, reticulum, omasum and abomasum similar to the domestic ruminants. Microscopically, rumen and abomasum are similar to the domestic ruminants. The reticulum and the omasum, however, present specific characteristics such as keratin on the top of the reticulum, small epithelial projections and omasum folds covered with discrete papillae.