Strong Immune Function Research Articles

Egg Mass Influences Nestling Quality in Tree Swallows, But There is no Differential Allocation in Relation to Laying Order or Sex

AbstractAbstract. Maternal allocation of resources to eggs and nestlings can potentially have a profound influence on offspring phenotype and fitness. However, it is often unclear how much of the variation in offspring quality is due to maternal or environmental effects. We examined the influence of maternal and environmental effects on egg mass and nestling quality (growth and immune function) in Tree Swallows (Tachycineta bicolor). There was no evidence that the allocation of maternal resources to eggs varied with laying order or offspring sex. Thus, there was no evidence of adaptive maternal allocation to eggs in terms of mass. Instead, egg mass in Tree Swallows appeared to be influenced primarily by ambient temperature during egg formation and differences among females. Nonetheless, female Tree Swallows were likely to realize substantial benefits from producing larger eggs because those young were larger at hatching and grew faster. Furthermore, nestlings that grew faster had a stronger immune function at 11 days of age. Our results suggest that the positive relationship between nestling growth and survival may be due, in part, to the effects of an enhanced immune response.

EGG MASS INFLUENCES NESTLING QUALITY IN TREE SWALLOWS, BUT THERE IS NO DIFFERENTIAL ALLOCATION IN RELATION TO LAYING ORDER OR SEX

Abstract. Maternal allocation of resources to eggs and nestlings can potentially have a profound influence on offspring phenotype and fitness. However, it is often unclear how much of the variation in offspring quality is due to maternal or environmental effects. We examined the influence of maternal and environmental effects on egg mass and nestling quality (growth and immune function) in Tree Swallows (Tachycineta bicolor). There was no evidence that the allocation of maternal resources to eggs varied with laying order or offspring sex. Thus, there was no evidence of adaptive maternal allocation to eggs in terms of mass. Instead, egg mass in Tree Swallows appeared to be influenced primarily by ambient temperature during egg formation and differences among females. Nonetheless, female Tree Swallows were likely to realize substantial benefits from producing larger eggs because those young were larger at hatching and grew faster. Furthermore, nestlings that grew faster had a stronger immune function at 11 days of age. Our results suggest that the positive relationship between nestling growth and survival may be due, in part, to the effects of an enhanced immune response.

Pharmacology Review

After completing this article, readers should be able to: 1. Describe the pharmacology of drug transfer into human milk. 2. Delineate the tools that the neonatologist can use to evaluate the relative risk for a breastfeeding infant if certain medications are used by his or her mother. 3. Describe the effects of various medications on the production of milk. 4. Characterize drug pharmacokinetics that can be used to reduce transfer of medications to milk and reduce the infant’s exposure. 5. Provide a method for evaluating the relative risk to an infant and those at low and high risk following exposure to various medications. New data continue to be published almost monthly that support human milk as the finest source of nutrition and the only source of exogenous immunoglobulins and protection against infections available to the newborn. During the first postnatal week, human milk is filled with immunoglobulins (IgG, IgA, and IgM), interferons, and other antibacterial substances, which results in colonization of the gastrointestinal (GI) tract of the newborn with benign bacterial flora. The presence of numerous growth factors (IgF-1), cytokines, and gastric hormones enhance development of protective barriers in the GI tract and stimulate elimination of the meconium that is present during gestation. Other key benefits to the infant include perfect nutrition, enhanced neurocognitive development, stronger immune function, and at least a threefold reduction in the incidence of infectious diseases such as upper respiratory tract infections, otitis media, and necrotizing enterocolitis. Although recent studies have suggested that the number of women who choose to breastfeed their infants is 72% and rising in the United States, the number of women who discontinue breastfeeding to take a medication is very high. Surveys in many countries indicate that 90% to 99% of women who breastfeed receive a medication during the first week postpartum. Another study of Scandinavian women …