OBJECTIVE In search of an ideal method of assisted hatching (AH), we compared the effects of conventional micropipette-AH and laser-AH on the blastocyst formation rate (BFR) and blastocyst cell numbers. METHODS Four- to five-week-old ICR female mice were paired with male mice after superovulation using Pregnant mare's serum gonadotropin (PMSG) and hCG. The two-cell embryos were flushed from t...

considering the crucial importance of daphnia species in aquaculture, in particular for artificially- cultured sturgeon fry, a comprehensive study on the hatching requirements of their diapausing eggs seemed to be inevitable in order to obtain the ideal hatching technique. to do so, the ephippial eggs were collected from live food ponds in the cultivation and breeding centre of gorgan and after...

The viability of Ochlerotatus albifasciatus (Macquart) eggs stored at room temperature and at 5oC was studied over 31 months. After 12, 18 and 31 months of storage, eggs were acclimatized at 22oC for ten days, and then inundated twice every seven days. The effect of the storage period on the percentage of hatching was analyzed by one way ANOVA. Differences on the hatching response between the f...

An extensive study was conducted from March 2007 to February 2012 on hatching success of saltwater crocodile (Crocodylus porosus) in the Reptiles Farm Ltd. (RFL) located at Hatiber village of Uthura union under Bhaluka upazila in Mymensingh. The study was mainly based on direct field observation and some previous data collected by farm’s technicians. A special type of incubator having 98-100% m...

The effect of dormancy in zooplankton populations is still unknown, largely because of the lack of methods to estimate hatching and production of the dormant stages. This study aimed to compare the production and hatching rates of ephippia of Daphnia laevis between thermal stratification and mixing periods in Jacaré Lake (Middle Rio Doce, Minas Gerais, Brazil). For this, we collected ephippia o...

BACKGROUND Varied clinical outcomes of assisted hatching (AH) have been reported. We attempt to investigate whether the size of the zona opening created by AH is adequate for blastocyst hatching, and, if not, set up a new method to improve it. METHODS A new AH technique, long zona dissection (LZD), was established, and experiments were performed to compare the effects of different sizes of zo...

Juvenile fish survival is often strongly density dependent and results in relatively consistent average recruitment over a wide range of spawning stock biomasses. Hatching date-dependent mortality can limit contributions of individual hatching sub-cohorts (i.e., fish hatched in one period relative to another within the overall hatching distribution) to the year class and influence the potential...

The viability of Ochlerotatus albifasciatus (Macquart) eggs stored at room temperature and at 5 degrees C was studied over 31 months. After 12, 18 and 31 months of storage, eggs were acclimatized at 22 degrees C for ten days, and then inundated twice every seven days. The effect of the storage period on the percentage of hatching was analyzed by one way ANOVA. Differences on the hatching respon...

The aim of this study was to determine the development time of embryos and to estimate the hatching rates of resting eggs of cladocerans found in the sediment of Guanabara Bay, Rio de Janeiro, Brazil, under experimental conditions. Eggs were sorted by species (Penilia avirostris--Sididae; Pleopis polyphemoides and Pseudevadne tergestina--Podonidae) and incubated at a temperature of 25 degrees C...