Intraspecific variation in egg size and hatching size, and the genetic and environmental trade-offs that contribute to variation, are the basis of the evolution of life histories. The present study examined both univariate and multivariate temperature-mediated plasticity of life-history traits, as well as temperature-mediated trade-offs in egg size and clutch size, in two planktotrophic species...

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 ...

A study was conducted to evaluate the production and hatching performances of hilly chickens naked neck (NN) at areas Naikhongchari regional station research farm Bangladesh Livestock Research Institute (BLRI). The experimental were reared in an open-sided poultry house under intensive management system for a period 18 month. birds allowed take feed clean drinking water ad libitum. Data on prod...

The present study is based on the investigation of a soil hyphomyces, Paecilomyces lilacinus, an opportunistic bio-control agent. The egg pathogenic fungus Paecilomyces lilacinus is a unique strain with a wide range of activity against the most important plant parasitic nematodes. The aim of this study to evaluate the efficiency of P. lilacinus on parasitic nematodes Meloidogyne javanica on tom...

Hatching care has been reported for many taxonomic groups, from invertebrates to vertebrates. The sophisticated care that occurs around hatching time is expected to have an adaptive function supporting the feeble young. However, details of the characteristics of the adaptive function of hatching care remain unclear. This study investigated the hatching care of the subsocial shield bug, Parastra...

Eggs obtained from 46 and 42 weeks old meat (Hybro) and layer (Leghorn) breeders flocks, respectively were used to examine the effects of genetic type of birds and egg size (small, medium and large) on variables of eggshell characteristics and hatchability traits. The variables measured were egg weight (EW), egg surface area (ESA) and eggshell characteristics (shell conductance (EC), per cent s...

Chronic Cu toxicity was evaluated in the euryhaline copepod Acartia tonsa. Male and female copepods were exposed (6 d) separately to different combinations of Cu concentration and water salinity (5, 15, and 30 ppt) using different routes of exposure (waterborne, waterborne plus dietborne, and dietborne). After exposure, groups of one male and three female copepods were allowed to reproduce for ...

topical application with 100, 200 and 300 ng/ml phytohormone salicyclic acid on commercial traits was analysed in bivoltine csr2, csr4 and csr2xcsr4 crossbreed races of the silkworm, bombyx mori l. the results showed that there was significant increase in larval weight female cocoon weight, male cocoon shell weight, and hatching percentage with 100 and 200 ng/ml, silkgland weight, female cocoon...

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 ...

The identification of novel targets for controlling the sheep blowfly is an important process for discovering new generation compounds that are safer and more environmentally friendly. Experiments in our laboratory have indicated a role for serine proteases in influencing egg hatching in the sheep blowfly. Isolation of the proteases involved using benzamidine affinity chromatography identified ...