The age structures of populations of African annual Nothobranchius spp. were examined for the first time. Daily increments in sagittal otoliths of Nothobranchius furzeri, Nothobranchius kadleci, Nothobranchius orthonotus and Nothobranchius rachovii from southern and central Mozambique were used for age determination. Four hypotheses were tested: (1) timing of hatching is consistent with the cal...

Although it is well documented that hatching asynchrony in birds can lead to competitive and developmental hierarchies, potentially greatly affecting growth and survival of nestlings, hatching asynchrony may also precipitate modulations in neuroendocrine development or function. Here we examine sibling variation in adrenocortical function in postnatally developing, asynchronously hatching Ameri...

Electrostatic charging of particles in enclosed spaces has been shown to be an effective means of reducing airborne dust. Dust generated during the hatching process has been strongly implicated in Salmonella transmission, which complicates the cleaning and disinfecting processes for hatchers. Following two preliminary trials in which dust reduction was measured, four trials were conducted to ev...

The mammalian embryo is encased in a glycoproteinaceous coat, the zona pellucida (ZP) during preimplantation development. Prior to implantation, the blastocyst must undergo 'hatching' or ZP escape. In hamsters, there is a thinning of the ZP followed by a focal lysis and a complete dissolution of the ZP during blastocyst hatching. Earlier studies from our laboratory have indicated a role for cys...

OBJECTIVE In search of an ideal method of assisted hatching (AH), we compared the effects of conventional micropipette-AH and laser-AH on the blastocyst formation rate (BFR) and blastocyst cell numbers. METHODS Four- to five-week-old ICR female mice were paired with male mice after superovulation using Pregnant mare's serum gonadotropin (PMSG) and hCG. The two-cell embryos were flushed from t...

Adaptive plasticity at switch points in complex life cycles (e.g., hatching, metamorphosis) is well known, but the evolutionary history of such plasticity is not. Particularly unclear is how a single plastic response (e.g., shifts in hatching timing) evolves to respond to different threats and cues (e.g., abiotic and biotic). We conducted a comparative phylogenetic study of hatching plasticity ...

Ethoprop, oxamyl, PP 156, fenamiphos, carbofuran , AC 64,475, Bunema M, CG 12223, aldicarb, aldicarbsulfoxide, and aldicarbsulfone were tested for their effects on hatching and emergence of larvae from cysts of Heterodera schachtii. The oxime carbamates and carbofuran inhibited hatching , but this response was reversed by removing the chemical treatment . Inhibition of hatching by Bunema M and ...

An extensive study was conducted from March 2007 to February 2012 on hatching success of saltwater crocodile (Crocodylus porosus) in the Reptiles Farm Ltd. (RFL) located at Hatiber village of Uthura union under Bhaluka upazila in Mymensingh. The study was mainly based on direct field observation and some previous data collected by farm’s technicians. A special type of incubator having 98-100% m...