Insect molting and metamorphosis are regulated by two major insect hormones, the juvenile hormone (JH) and ecdysteroids. Ecdysteroids initiate the molting process, whereas JH dictates the character of a molt. At the critical period of ecdysteroid rise, the presence or absence of JH directs larval-larval molting or metamorphosis. Ecdysteroid after binding with its receptor activates the expressi...

A study was conducted to evaluate skeletal quality and eggshell parameters of molted hens at the end of the second laying cycle. Sixty Single Comb White Leghorn hens were used for this study. There were 2 controls and 4 molting treatments: full-fed control 1 (82 wk old; FF1), full-fed control 2 (122 wk old; FF2), feed withdrawal (FW), 100% alfalfa (A100), 90% alfalfa/10% layer ration (A90), and...

In crustaceans, like all arthropods, growth is accompanied by a molting cycle. This cycle comprises major physiological events in which mineralized chitinous structures are built and degraded. These events are in turn governed by genes whose patterns of expression are presumably linked to the molting cycle. To study these genes we performed next generation sequencing and constructed a molt-rela...

Natural insecticides often do not provide a strong knock-down effect and have lower efficacy than synthetic pesticides. For an effective application of natural insecticides, it is essential to know the product’s mode action in detail. The commercial neem [Azadirachta indica A. Juss (Meliaceae)] product NeemAzal-T/S its influence on stage-specific mortality, development, reproduction rose aphids...

Stable isotope ratios of hydrogen (dD) and carbon (d13C) in feathers collected from Painted Buntings (Passerina ciris (L., 1758)) breeding in the midwestern United States revealed a surprising degree of variation in dD, as well as a clear bimodal signal in d13C in the innermost primary feather. Because this population does not molt on the breeding grounds, we reasoned that these observations co...

The heterodimer of the ecdysone receptor (EcR) and ultraspiracle (Usp), members of the nuclear receptors superfamily, is considered as the functional receptor for ecdysteroids initiating molting and metamorphosis in insects. Here we report the 1.95 A structure of the complex formed by the DNA-binding domains (DBDs) the EcR and the Usp, bound to the natural pseudopalindromic response element. Co...

After molting to maturity, female blue crabs must rebuild muscles atrophied to permit molting and grow larger ones commensurate with the larger exoskeleton. They also must acquire energy for oogenesis and for migration to high-salinity spawning habitat, a distance of >150 km for females mating in the Upper Chesapeake Bay. Using telemetry and mark–recapture techniques, postcopulatory females in ...