Fitness consequences of ectoparasitism are expressed over the lifetime of their hosts in relation to variation in composition and abundance of the entire ectoparasite community and across all host life history stages. However, most empirical studies have focused on parasite species-specific effects and only during some life history stages. We conducted a systematic, year-long survey of an ectop...

Although the molting cycle is a hallmark of insects and nematodes, neither the endocrine control of molting via size, stage, and nutritional inputs nor the enzymatic mechanism for synthesis and release of the exoskeleton is well understood. Here, we identify endocrine and enzymatic regulators of molting in C. elegans through a genome-wide RNA-interference screen. Products of the 159 genes disco...

STUDIES of the regeneration of feathers after plucking show the existence of considerable differences in the time intervals before the commencement of regeneration in individual feathers. In normal moulting, the development of the new feather starts before the old feather is shed, and as growth of the new feather continues and it emerges from the follicle, it may frequently be seen projecting w...

Ion transport and metabolism in the posterior midgut before, during and after the molt to the fifth instar of the tobacco hornworm Manduca sexta were investigated. In situ measurements reveal that the transepithelial potential difference of the posterior midgut falls during the molting process. This finding was confirmed by in vitro experiments in which it was demonstrated that both the transep...

It is well known that many insects, and especially many Orthoptera, are capable of regenerating autotomized and amputated legs (Godelmann, 1901; Bordage, 1905; Megusar, 1910; Friedrich, 1930). Very little is known, however, about those factors governing regeneration, those initiating the excessive growth in regeneration, and those suppressing growth when the regenerated leg has reached a normal...

The study aimed to evaluate the effects of 1 % zinc propionate as a molting agent on egg production and quality, certain biochemical blood parameters, hepatic and renal residues of zinc in laying hens. Sixty laying hens of 64 weeks old were divided into two equal groups; control non molted group, that fed a layer ration without additives and molted group, that fed a layer ration with 1% zinc pr...

The aim of this study was to evaluate effects of alfalfa and fructooligosaccharides (FOS) on molting performance and bone parameters compared with the conventional feed withdrawal molting procedure. A total of 36 Single Comb White Leghorn hens (84 wk of age) were used for this experiment. The hens were divided into 6 treatment groups with 6 birds per treatment: pre-trial control (PC), full fed ...

Caenorhabditis elegans molting is a process during which the apical extracellular matrix of the epidermis, the cuticle, is remodeled through a process of degradation and re-synthesis. Using a genetic approach, we identified nekl-3 as essential for the completion of molting. NEKL-3 is highly similar to the mammalian NEK kinase family members NEK6 and NEK7. Animals homozygous for a hypomorphic mu...

The blacklegged tick (Ixodes scapularis) is an important vector of emerging human pathogens. It has three blood-feeding stages, as follows: larva, nymph, and adult. Owing to inefficient transovarial transmission, at least for the Lyme disease agent (Borrelia burgdorferi), larval ticks rarely hatch infected, but they can acquire infection during their larval blood meal. Nymphal ticks are primari...

Animal development requires temporal coordination between recurrent processes and sequential events, but the underlying timing mechanisms are not yet understood. The molting cycle of C. elegans provides an ideal system to study this basic problem. We recently characterized LIN-42, which is related to the circadian clock protein PERIOD, as a key component of the developmental timer underlying rh...