1. A definite chronological sequence of events occurs in the eggs and follicles of rabbits after mating or after the injection of ovulation-inducing substances. The follicle secretes secondary liquor folliculi, and there occurs a separation of the corona radiata from strands connecting it to the follicle cells. The ovum goes through nuclear maturation with as climax the production of the first ...

Although oocytes of many teleost fish, especially marine species, are subjected to a hydration process during meiotic maturation, which leads to an important volume increase, no noticeable hydration of the preovulatory oocyte has ever been reported in rainbow trout (Oncorhynchus mykiss). In the present study, oocyte water content and dry mass were monitored using consecutive samples taken in vi...

N THE parasitic wasp Habrobracon juglandis (Ashm.), when a cross of I unrelated stocks is made, males (haploid) come from unfertilized eggs and females (diploid) from fertilized eggs. When the parental stocks are closely related, not only males from unfertilized eggs but also males (diploid) from fertilized eggs appear. That such biparental males should be produced was puzzling until WHITING br...

Synovigenic insects (i.e., insects emerging with few ripe eggs and maturing more eggs during the course of their lifetime) may suffer from transient egg limitation due to the stochastic nature of encounters with patchy hosts and the low availability of ripe eggs at any given time point. Egg limitation also affects the stability of host-parasitoid models. Thus, quantification of the behavioral d...

Immunofluorescent anti-tubulin staining has been used to follow nuclear progression from dictyate to metaphase II during meiotic maturation of mouse oocytes in vitro. Antibody directed against tubulin isolated from sea-urchin eggs decorates the metaphase I and metaphase II spindles, as well as the cytoplasmic bridge, midbody, and polar body of the maturing mouse oocytes. Changes in the tubulin-...

Ca2+ is the most universal second messenger in cells from the very first moment of fertilization. In all animal species, fertilized eggs exhibit massive mobilization of intracellular Ca2+ to orchestrate the initial events of development. Echinoderm eggs have been an excellent model system for studying fertilization and the cell cycle due to their large size and abundance. In preparation for fer...

The development of Haplorchis taichui was studied in sixteen mice, Mus musculus. Metacercarial cysts of H. taichui were obtained from the freshwater fish, Thynnichthys thynnoides, collected in Chiang Mai Province, north Thailand. Approximately 200 active metacercariae were orally introduced into each mouse. Two mice were randomly sacrificed and necropsied daily from day 2-9 postinfection (pi). ...

body fluids (Evans, 1993) is reflected in their eggs (Davenport et al., 1981; Riis-Vestergaard, 1982; Watanabe and Kuo, 1986; Mangor-Jensen, 1987; LaFleur and Thomas, 1991). However, these eggs have none of the advantages of the adult osmoregulatory organs associated with homeostasis, and the typical drinking activity seems to start at, or shortly before, hatching (Guggino, 1980; Mangor-Jensen ...

The increasing spread of the Asian tiger mosquito, Aedes albopictus, in Europe and US raises public health concern due to the species competence to transmit several exotic human arboviruses, among which dengue, chikungunya and Zika, and urges the development of suitable modeling approach to forecast the spatial and temporal distribution of the mosquito. Here we developed a dynamical species dis...

The aim of ovarian stimulation in fertility treatment is to increase the number large follicles and hence eggs that can be retrieved for vitro fertilisation (IVF). However, inter- intra-individual variability menstrual cycle response drugs complicate planning prediction. Hence, many mathematical models have been developed support decisions. In this article, we give an overview mechanistic cover...