For the first part of the study, the researchers transplanted precursors of blood cells, which are precursors of all the macrophages, a mouse to another child. The transplanted cells could not be differentiated in the animal recipient. These results suggest that the microglia origin before birth, during embryonic life.Microglia are thought to play an important role in the development of many diseases of the brain, and that the defective microglia could lead to release of inflammatory molecules, which could contribute to the development of degenerative brain diseases.

Next, the researchers used a mouse model that expresses fluorescent biosensors in blood precursors to determine when, during the age of the embryonic precursors develop into microglia. Once activated the fluorescence does not go away and all the cells that develop from precursors should remain fluorescent fluorescent. The researchers have already activated fluorescent seven days after conception. When they examined adult mice have found fluorescent microglia, macrophages but not fluorescent.

In the newspaper article, published in the Ecological Society of America Frontiers in Ecology and Environment, Alexander explains the significant differences in behavior from that found in domestic dogs in Kenya and Botswana, which parallel the differences in disease mortality in wild dog populations in Africa. Most domestic dogs in Kenya spend the day with grazing cattle, accompanied by shepherds, while in Botswana, most domestic dogs remain in the village, because the cattle are normally left to graze unattended.

As a result, African wild dogs have much higher rates of mortality of the disease in Kenya, where they have more contact with domestic dogs.