Ovulation

Ovulation, the movement of an egg from the ovary into the lateral oviduct, may or may not be well separated in time from the actual process of egg laying (oviposition). In most insects, especially those that lay their eggs singly (e.g., Rhodnius), oviposition immediately follows ovulation. However, in insects that deposit eggs in batches or are viviparous (Chapter 20, Section 8.3) the two events may occur several days apart. For example, in Schistocerca gregaria the eggs accumulate in the lateral oviducts for a week prior to being laid.

Ovulation is induced by a neurosecretory factor from the brain. In Rhodnius, for example, median neurosecretory cells produce a myotropic peptide that is stored in the corpora cardiaca. Mating is an important (though not the only) stimulus for release of the peptide, which induces contractions of the ovarian muscles. However, as mating may occur well in advance of ovulation, it cannot be the only factor involved. It appears that mating triggers periodic releases of ecdysone from the ovary (coincident with the maturation of an egg), and it is this hormone that effects the release of the peptide from the corpora cardiaca (Davey, 1985b).

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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