Hepatic Gene Expression Profiling of American Kestrels () Exposed In Ovo to Three Alternative Brominated Flame Retardants.

A number of brominated flame retardants (BFRs) have been reported to interfere with the thyroid signaling pathway and cause oxidative stress in birds, yet the underlying shifts in gene expression associated with these effects remain poorly understood. In this study, we measured hepatic transcriptional responses of 31 genes in American kestrel () hatchlings following in ovo exposure to one of three high-volume alternative BFRs: 1,2-bis(2,4,6-tribromophenoxy) ethane (BTPBE), bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), or 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB). Hatchling kestrels exhibited shifts in the expression of genes related to oxidative stress ( and ), thyroid hormone metabolism and transport (, and ), lipid and protein metabolism (PPAR, HMGCR, FAB1, and LPL), and cytokine-mediated inflammation ( and ).

Bold Behavior Is Associated with Genes That Regulate Energy Use but Does Not Covary with Body Condition in Food-Restricted Snails.

AbstractTheoretical models about the relationship between food restriction and individual differences in risk-taking behavior (i.e., boldness) have led to conflicting predictions: some models predict that food restriction increases boldness, while other models predict that food restriction decreases boldness.

Perception of infection: disease-related social cues influence immunity in songbirds.

While avoidance of sick conspecifics is common among animals, little is known about how detecting diseased conspecifics influences an organism's physiological state, despite its implications for disease transmission dynamics. The avian pathogen (MG) causes obvious visual signs of infection in domestic canaries (), including lethargy and conjunctivitis, making this system a useful tool for investigating how the perception of cues from sick individuals shapes immunity in healthy individuals. We tested whether disease-related social information can stimulate immune responses in canaries housed in visual contact with either healthy or MG-infected conspecifics.

Male zebra finches exposed to lead (Pb) during development have reduced volume of song nuclei, altered sexual traits, and received less attention from females as adults.

Lead (Pb) is a pervasive global contaminant that interferes with sensitive windows for neurological development and causes oxidative damage to tissues. The effects of moderate and high exposure to Pb have been well-studied in birds, but whether low-level early-life exposure to Pb influences adult phenotype remains unclear. Female songbirds use a male's song and coloration to discriminate between high- and low-quality males.

Effects of sublethal application of Deepwater Horizon oil to bird eggs on embryonic heart and metabolic rate.

Following large crude oil spills, oil from feathers of brooding birds and oiled nesting material can transfer to eggs, resulting in reduced embryonic viability for heavily oiled eggs. Eggs may also be subjected to trace or light oiling, but functional teratogenic effects from sublethal crude oil exposure have not been examined. We assessed whether sublethal application of weathered Deepwater Horizon crude oil to the eggshell surface alters heart rate and metabolic rate in Zebra Finch (Taeniopygia guttata) embryos.

Fluorescent Heme Degradation Products Are Biomarkers of Oxidative Stress and Linked to Impaired Membrane Integrity in Avian Red Blood Cells.

Oxidative stress is generally understood to be an important mediator of life-history traits, yet the specific relationships between oxidative stress and life-history traits have been difficult to describe because there is often a lack of covariation among biomarkers of oxidative stress. For instance, although oxidative damage to red blood cell (RBC) membranes can lead to pathological conditions (i.e.

Bioenergetics-adverse outcome pathway: Linking organismal and suborganismal energetic endpoints to adverse outcomes.

Adverse outcome pathways (AOPs) link toxicity across levels of biological organization, and thereby facilitate the development of suborganismal responses predictive of whole-organism toxicity and provide the mechanistic information necessary for science-based extrapolation to population-level effects. Thus far AOPs have characterized various acute and chronic toxicity pathways; however, the potential for AOPs to explicitly characterize indirect, energy-mediated effects from toxicants has yet to be fully explored. Indeed, although exposure to contaminants can alter an organism's energy budget, energetic endpoints are rarely incorporated into ecological risk assessment because there is not an integrative framework for linking energetic effects to organismal endpoints relevant to risk assessment (e.

Is altered behavior linked to cellular energy regulation in a freshwater mussel (Elliptio complanata) exposed to triclosan?

Environmental stress may alter the bioenergetic balance of organisms by resulting in greater energy investment into detoxification processes, which diverts energy from other biological functions. Here, we examine responses to triclosan (TCS) exposure in a freshwater mussel across multiple biological levels: behavioral (e.g.

AMP-activated protein kinase is a biomarker of energetic status in freshwater mussels exposed to municipal effluents.

Although biomarkers are frequently used to assess sublethal effects of contaminants, a lack of mechanistic linkages to higher-level effects limits the predictive power of biomarkers. Bioenergetics has been proposed as a framework for linking cellular effects to whole-animal effects. We investigated sublethal effects of exposure to wastewater treatment facility effluent in freshwater mussels in situ, thereby capturing ecologically relevant exposure conditions.