In temperate regions, the seasonal dynamics of Aedes aegypti (L.) (Diptera: Culicidae) is mainly influenced by temperature. It is assumed that, during the winter season, the population remains as eggs and that the development and population growth of surviving eggs begin during the following spring. The aim of the current study was to assess the temporal dynamics of egg hatching of Ae. aegypti ...

1. When the eggs of the skin parasitic monogenean Entobdella soleae are subjected in the laboratory to alternating periods of light and darkness (LD 12:12, LD 6:18 or LD 18:6) at constant temperature (selected from the range 12-16 °C), hatching is rhythmical, most of the oncomiracidia emerging during the first 4 h of the period of illumination on each successive day. 2. Rhythmicity in response ...

Laboratory-based methods to test egg viability include staining with Meldola's Blue and/or juvenile (J2) hatching assays using potato root diffusate (PRD). These two methods have not been tested under identical conditions to directly compare their assessments of Globodera egg viability. Using two bioassay strategies, cysts from a Globodera sp. population found in Oregon were subjected to both v...

The aim of this study was to evaluate the effect of environmental factor such as month and season on the hatching features of ducks, and to determine the suitable months or season for hatching. For this purpose, the hatching records of different duck breeds raised in ElSerw water fowl farm belonging to Turkey and Water Fowl Breeding Research Department, Animal Production Research Institute, fro...

Lipids and essential fatty acids, particularly the highly unsaturated fatty acids, 20:5n-3 (eicosapentaenoic acid; EPA), 22:6n-3 (docosahexaenoic acid; DHA) and 20:4n-6 (arachidonic acid, AA) have been shown to be crucial determinants of marine fish reproduction directly affecting fecundity, egg quality, hatching success, larval malformation and pigmentation. In Atlantic cod (Gadus morhua L.) c...

Background: Fluoxetine (ProzacTM) is one of the most popular antidepressant that can be released to aquatic systems via sewage-treatment effluents. It is suspected to provoke substantial effects in the aquatic environment. Methods: In spawning tanks, specimens were exposed to concentrations of 0 and 0.54 µgl-1 fluoxetine from male introduction until the larvae had hatched. Prior to spawning, n...

This study deals with the effects of different hatcher temperatures on hatching traits in modern commercial broiler eggs during the last five days of incubation. The hatching eggs were obtained from a 52wk old (Ross 308) flock. All eggs were distributed randomly into one incubator and incubated for 17 d using uniform conditions (37.6 ± 0.5 °C and 58% relative humidity). At the start of 18 days ...

Bacteria (including salmonellae) can be pulled into and through the shell and membrane of broiler hatching eggs as they cool. When this occurs, salmonellae are out of reach of a surfaceapplied chemical treatment, because direct contact is usually required to achieve a kill. Over many years of research, a large number of disinfectant chemicals have been tested on hatching eggs. We have found H2O...

In a marsh-breeding population of red-winged blackbirds, the sex ratio of offspring that survived to leave the nest varied with maternal age. Old mothers produced an excess of male fledglings, middle-aged mothers produced almost equal proportions of males and females, and young mothers produced nearly twice as many females as males. More males than females hatched from the eggs of old mothers, ...