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Nest site availability is a factor associated with conspecific brood parasitism (CBP) in birds. The house sparrow (Passer domesticus) population on Dassen Island, South Africa, suffers from limited nesting space availability. We estimated the incidence of CBP in this population and determined experimentally whether sparrows retain the capacity to recognise and reject parasitic eggs. Other strategies that have evolved to thwart brood parasitism include nest guarding and nest defence. The presence of an intruding female near a nest may result in antagonistic behaviour as well as increasing the rejection of parasitic eggs (i.e., additive stimulus). This study tests if the presence of an intruding conspecific female generates an additive stimulus or whether nest guarding/defence and egg rejection are antagonistic responses, which has been studied principally in cases of interspecific brood parasitism (IBP). Despite space limitations, CBP was not detected in this population, and one third of foreign eggs were rejected. However, nest guarding/defence was not related to egg recognition and rejection. Egg rejection in this population does not appear to depend on the probability of nests being parasitised or on an inability to assume the costs associated with nest guarding/defence and with egg rejection. [ABSTRACT FROM AUTHOR]

Diets of infants across the world are commonly deficient in multiple micronutrients during the period of growth faltering and dietary transition from milk to solid foods. A randomized placebo controlled trial was carried out in Indonesia, Peru, South Africa, and Vietnam, using a common protocol to investigate whether improving status for multiple micronutrients prevented growth faltering and anemia during infancy. The results of the pooled data analysis of the 4 countries for growth, anemia, and micronutrient status are reported. A total of 1134 infants were randomized to 4 treatment groups, with 283 receiving a daily placebo (P), 283 receiving a weekly multiple micronutrient supplement (WMM), 280 received a daily multiple micronutrient (DMM) supplement, and 288 received daily iron (DI) supplements. The DMM group had a significantly greater weight gain, growing at an average rate of 207 g/mo compared with 192 g/mo for the WMM group, and 186 g/mo for the DI and P groups. There were no differences in height gain. DMM was also the most effective treatment for controlling anemia and iron deficiency, besides improving zinc, retinol, tocopherol, and riboflavin status. DI supplementation alone increased zinc deficiency. The prevalence of multiple micronutrient deficiencies at baseline was high, with anemia affecting the majority, and was not fully controlled even after 6 mo of supplementation. These positive results indicate the need for larger effectiveness trials to examine how to deliver supplements at the program scale and to estimate cost benefits. Consideration should also be given to increasing the dosages of micronutrients being delivered in the foodlets.

Infants in developing countries are at risk of concurrent micronutrient deficiencies, because the same causative factors may lead to deficiencies of different micronutrients. Inadequate dietary intake is considered one of the major causes of micronutrient deficiencies, especially among poor and underprivileged children in developing countries. Operational strategies and distribution systems are often duplicated when supplementation programs for single micronutrients are implemented at the same time. The International Research on Infant Supplementation (IRIS) trial was conducted in four distinct populations on three continents: Africa, Latin America, and Asia. The participating countries were South Africa, Peru, Vietnam, and Indonesia. The study had a randomized, doubleblind, placebo-controlled design. Each country aimed to enroll at least 70 infants per intervention group (65 + 5 anticipated dropouts). The micronutrient vehicle was in the form of a "foodlet" (food-like tablet) manufactured as chewable tablets, which were easy to break and dissolve, and which had the same taste, color, and flavor for all countries. Children were randomly assigned to one of four 6-month intervention groups: group 1 received a daily foodlet containing multiple micronutrients; group 2 received a daily placebo foodlet containing no micronutrients; group 3 received a weekly foodlet that contained multiple micronutrients (twice the dose of the daily foodlet) and placebo foodlets on the other days of the week; group 4 received a daily foodlet containing only 10 mg of elemental iron. The IRIS Trial aimed to examine the prevalence of multi-micronutrient deficiencies in 6- to 12-month-old infants from rural populations, and to examine the efficacy of multi-micronutrient supplementation in infants from the different countries included in the study. This paper describes the general methodology of the IRIS trial and the operational differences among the country sites.