The present book is a presentation of transmission electron micrographs, depicting ultrastructure of oogenesis in amphistome digenetic trematode commonly parasitizing the livestock and poultry in India. The state of Rajasthan is famous for its cattle wealth. The economy of rural people largely depends on cattle. The ruminants have been found to suffer from various diseases like Paramphistomiasis and Facioliasis. These diseases cause morbidity and mortality in ruminants affecting socio-economic conditions of people. The book will help in understanding the problems of ruminants and pave a path towards a progressive state as well as nation. The present book is very significants as, * Present book is of great importance from-verterinary standpoints. * The book will help in understanding od certain histological, cytological and physiological aspects of ovary and oogenesis of digenetic trematode. *Ultrastructure of ovary and oogenesis would provide knowledge for chemotherapeutic measures.