J Exp Zool A Ecol Integr Physiol
December 2020
Exposure to stressors over prolonged periods can have fitness-relevant consequences, including suppression of immune function. We tested for effects of presence of an invasive species threat on a broad panel of immune functions of a coexisting lizard. Eastern fence lizards (Sceloporus undulatus) have been exposed to invasive fire ants (Solenopsis invicta) for over 80 years.
View Article and Find Full Text PDFFibroblast growth factor 23 (FGF-23) is proposed to be the hormone that controls phosphate (P) homeostasis in chickens. This study was initiated to investigate the effect of feeding young chicks diets that were either adequate (0.45%) or marginal (0.
View Article and Find Full Text PDFComp Biochem Physiol A Mol Integr Physiol
April 2016
Medullary bone is a specialized bone found in the marrow cavity of laying birds. It provides a significant contribution to the calcium supply for egg shell formation. Medullary bone is distinguished from cortical bone by the presence of large amounts of a keratan sulfate proteoglycan (KSPG).
View Article and Find Full Text PDFWhite-throated sparrows increase fat deposits during pre-migratory periods and rely on these fat stores to fuel migration. Adipose tissue produces hormones and signaling factors in a rhythmic fashion and may be controlled by a clock in adipose tissue or driven by a master clock in the brain. The master clock may convey photoperiodic information from the environment to adipose tissue to facilitate pre-migratory fattening, and adipose tissue may, in turn, release adipokines to indicate the extent of fat energy stores.
View Article and Find Full Text PDFSerotonin in blood plasma is primarily synthesized in the duodenum, as brain derived serotonin does not cross the blood-brain barrier. Because serotonin in the brain and retina is synthesized under the control of a circadian clock, we sought to determine if a circadian clock in the duodenum regulates serotonin synthesis and release in blood. We examined gene expression in the duodenum of chickens at different times of the day and found that the duodenum rhythmically expresses molecular circadian clock genes and genes controlling serotonin biosynthesis, specifically tryptophan hydroxylase, in a light dark cycle (LD).
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