Parental food allocation in birds has long been a focal point for life history and parent-offspring conflict theories. In asynchronously hatching species, parents are thought to either adjust brood size through death of marginal offspring (brood reduction), or feed the disadvantaged chicks to reduce the competitive hierarchy (parental compensation). Here, we show that parent American coots (Ful...

The difficulty of obtaining in the laboratory massive liberation of barnacle nauplii com­ parable with that which occurs in nature led to an investigation of the effect of various factors on the hatching process. The hatching of egg masses in vitro is inhibited only at such low oxygen concentrations as to make the control of hatching by oxygen tension unlikely. Variations in salinity are simila...

A study was conducted to investigate Fe requirements of broiler breeders. One-hundred-fifty-six Cobb 500 broiler breeder hens were individually placed in electrostatically painted cages at 22 weeks. The study was composed of an adaptation phase, in which hens were fed corn-soy-wheat bran diets until 35 wks. An Fe deficient mash diet (24.6 ppm Fe) was provided from 35 to 46 wk in order to induce...

Plankton research has always been an important area of biology. Due to various environmental issues and other research interests, plankton hatching and harnessing has been extremely red-marked zone for bio-aqua scientists recently. To counter this problem, no wireless sensor assisted technique or mechanism has yet not been devised. In this literature, we propose a novel approach to pursue this ...

The molecular regulation of mammalian peri-implantation development is complex and difficult to study in vivo. We successfully cultured hamster blastocysts through hatching and peri-attachment stages, using a chemically defined medium, HECM-2h. Using this system, we showed that a species-specific, embryonic cysteine-like protease is involved in blastocyst hatching and that the process is modula...

Hatching lines are often used in line illustrations to convey tone and texture of a surface. In this report an approach for rendering hatched line drawings for polygonal meshes is presented.The proposed method allows the generation of hatching lines for interactive on-screen display as well as for vector-based printer output.We use local curvature information to compute streamlines on the surfa...

—Three trials were conducted to evaluate the effect of hydrogen peroxide (H2O2) treatment on the hatching success of channel catfish Ictalurus punctatus when administered during egg incubation as a 15-min bath or as a flow-through treatment. In the first trial, initial treatment with 100 mg povidone iodine/L followed by daily 15-min baths of 250 mg H2O2/L yielded a 26% increase (P , 0.05) in ha...

Changes in nutritional constituents and enzyme activities were clarified yellowfin tuna (YFT, Thunnus albacares) eggs during embryonic development, from immediately after fertilization to hatching. The protein levels the gradually increased with development until completion of In contrast, triglyceride (TG) free amino acid (FAA) declined hatching was complete, although energy composition FAAs l...

The suitability of using optical-density (OD) measurements after a 6-h incubation period to determine bacterial contamination on hatching eggs was evaluated. A total of 154 hatching eggs, from five different flocks, were examined visually and bacterial counts and OD measurements of egg washings after 6 h of incubation at 37 degrees C were carried out to determine the levels of bacterial contami...