Egg hatching has been studied in Aedes aegypti (L.) through scanning electron microscopy. The first sign of egg hatching is a small protrusion on the eggshell in the anterior pole. The larval movement provokes a crack in the eggshell with the egg buster located in the dorsal head. The egg buster provokes a small transverse fissure in the eggshell that gradually increases in the chorion. Then, t...

The golden apple snail (Pomacea maculata Perry) is an invasive species that lays its eggs out of water but is otherwise aquatic. To investigate this behavior and potential management techniques, we conducted experiments to examine the physical effects of immersion and underwater egg predation on hatching success. Predation on submerged eggs by P. maculata adults reduced hatching success by ,99%...

Hatching studies with Heterodera glycines typically have been conducted with a mixture of egg-mass and encysted eggs. Laboratory research was conducted to compare hatching of H. glycines eggs from external egg masses with that of eggs extracted from within females and cysts (encysted eggs). Egg-mass eggs were collected by soaking infected soybean roots in 0.5% sodium hypochlorite, and encysted ...

This study summarizes optimization of techniques for common carp artificial propagation including improvements of activation solution (AS), the process of insemination, and elimination of egg stickiness. The optimum gamete ratio for good fertilization and hatching rate ranged from 8490 to 23 672 spermatozoa per egg, when dechlorinated tap water was used. Optimal ratio between eggs (weight in g)...

BACKGROUND Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with fresh...

An experiment was conducted to assess the optimum nutrient requirement and ideal mating ratios for Alabio ducks for production of fertile eggs and hatchability under rural feeding management. A total of 135 forty weeks old females and 27 males were used in the study. They were fed on low (17.5%), medium (19.5%) and high (21.5%) crude protein (CP) in diets containing approximately 3050 kcal of m...

Using a global data set on egg hatch times in zooplanktonic and nektonic ectotherms from marine waters, the combined effects of body size, temperature and life-history attributes on development times were examined. After correcting for mass and temperature the mean egg hatch times (from laying to hatching) were 20 times faster in some taxa than in others. Some of the divergence in hatch times c...

The clock protein PER is necessary for circadian control of egg-hatching behavior in the silkmoth Antheraea pernyi. Since the brain and midgut of the silkmoth embryo contain PER-positive cells, we examined the circadian clock potential of these embryonic tissues. Transplantation experiments indicate that the circadian clock controlling egg-hatching behavior resides in brain, and that a humoral ...