Morphological changes of cultured bovine blastocysts during hatching were observed using time-lapse videomicrography in order to investigate the patterns of the hatching process that occurred in the blastocysts and to determine whether the hatching patterns differed between blastocysts developed from fresh and cryopreserved embryos. Compacted morulae (CMs) were collected from superovulation-tre...

A female of the terrestrial crab Sesarma haematoeheir incubates 30,000-50,000 eggs on her abdomen. After 1 month of embryonic development, zoeae larvae are released into estuarine waters within 3-5 sec by means ofvigorous fanning motions of the abdomen. Hatching (breakage of the outer egg membrane) occurs on land just before larval release. The release behavior itself does not cause rupture of ...

Adult crickets (Gryllus bimaculatus) were maintained under a 12-h light:12-h dark cycle (LD 12:12). After oviposition, their eggs were incubated under different lighting regimens at 23 degrees C, and temporal profiles of egg hatching were examined. When the eggs were incubated in LD 12:12 or in DL 12:12 with a phase difference of 12h from LD 12:12, throughout embryogenesis, 88% to 97% of hatchi...

Epithelial gland systems play an important role in marine molluscs in fabricating lubricants, repellents, fragrances, adhesives or enzymes. In cephalopods the typically single layered epithelium provides a highly dynamic variability and affords a rapid rebuilding of gland cells. While the digestive hatching gland (also named Hoyle organ) is obligatory for most cephalopods, only four genera (Nau...

Twenty-five pesticides used in the production of rice and soybeans in Texas were tested in the laboratory to determine their toxicity to the eggs of Psorophora columbiae. A reduction in hatching rate occurred when eggs were treated with a herbicide formulation containing thiobencarb and with one containing a tank mixture of propanil and molinate. A carbaryl formulation induced hatching of eggs ...

the main objective of this study was to elucidate the effect of short- term exposure of japanese quail eggs to acute high incubation temperature on embryonic development and on the ability of post- hatched chicks to cope with subsequent heat stress conditions during the growing period. a total of 998 japanese quail eggs were divided into two groups, the first group (470 eggs) was maintained at ...

The life histories of many animals are characterized by niche shifts, the timing of which can strongly affect fitness. In the tree frog Agalychnis callidryas, which has arboreal eggs, there is a trade-off between predation risks before and after hatching. When eggs are attacked by snakes, tadpoles escape by hatching rapidly and falling into the water below. Eggs not attacked by snakes hatch lat...