© BSP 2013 Absence of brain in a Sparrowhawk embryo   Many anomalies can be caused by nutritiional deficiencies. Sperm cells in the vitelline membrane  Fluorescence microscopy is required to distinguish fertilsed and unfertilised eggs. Pathology of failed eggs (book) Many birders come across failed eggs when studying the reproductive success of birds. Mostly, these eggs are left, discarded or stored in a freezer for near-eternity. However, opening failed eggs can reveal important clues about the causes of egg failure and hence elucidate breeding limitations. This book is a practical guide to open failed eggs, linking your observations to probable causes and the backgrounds of encountered problems. Not only embryo anomalies are covered, but also aspects like (lack of) fertilisation, growth and development of bacterial populations, and relationships between primary and secondary causes of egg failures are presented. In 2000, Arnold van den Burg finished his PhD at The University of Nottingham’s Medical School on the causes of egg failures in wild birds. During the years that followed, more and more eggs were presented, and the idea to create this practical book took shape. Hopefully, this book will not only find its way to bird researchers in the field, as also bird keepers may find it useful. The book is expected to become available later this year, as will be announced on the website. This production will be in English and Dutch.     Author: Arnold van den Burg