Amadir: Livelihood and Resource Management in an Eritrean Highland Community: A development baseline

This publication presents the results of a study conducted in 2003 in Amadir, a village in the Central Highlands of Eritrea. It gives an overview of the natural resource base, livelihoods, farm management, and institutions that are important to the local community. The report concludes with a chapter on options for development as discussed with the village community and local administration. This report supports Eritrea's efforts to promote rural development. It contains an extensive summary in Tigrinya, as well as a large-scale satellite image and a large-scale land use map of the study area. The appendix presents a summary of the methods used in the study.

Immunocompetence of nestling great tits in relation to rearing environment and parentage

Theoretical models of host-parasite coevolution assume a partially genetic basis to the variability in susceptibility to parasites among hosts, for instance as a result of genetic variation in immune function. However, few empirical data exist for free-living vertebrate hosts to support this presumption. In a cross-fostering experiment with nestling great tits, by comparing nestlings of the same origin we investigated (i) the variance in host resistance against an ectoparasite due to a common genetic origin, (ii) the effect of ectoparasite infestation on cell-mediated immunity and (iii) the variance in cell-mediated immunity due to a common genetic origin. Ectoparasitic hen fleas can impair the growth of nestling great tits and nestling growth was therefore taken as a measure of host susceptibility. A common origin did not account for a significant part of the variation in host susceptibility to fleas. There was no significant overall effect of fleas on nestling growth or cell-mediated immunity, as assessed by a cutaneous hypersensitivity response. A common rearing environment explained a significant part of the variation in cell-mediated immunity among nestlings, mainly through its effect on nestling body mass. The variation in cell-mediated immunity was also related to a common origin. However, the origin-related variation in body mass did not account for the origin-related differences in cell-mediated immunity. The results of the present study thus suggest heritable variation in cell-mediated immunity among nestling great tits. [References: 49]