For successful fish culture the breeding of the fish is the most vital aspect and can not be even thought without the knowledge of breeding behavior of the fish, for that purpose the Endocrinological observations have to be carried out. During the last decade, fish endocrinology has observed stirring developments due to advanced research at all levels of biological organization. The book entitled as "CYCLIC ENDOCRINOLOGICAL CHANGES IN A TEMPERATE FISH" will serve as a great scientific tool in the field of fish endocrinology. The fish species of the tribe Oreinini of the family Cyprinidae breed in running water only and their induced breeding could not be carried out under controlled conditions in confined waters. It is because of our meager knowledge about the reproductive biology of these fishes. It is reported that their population is continuously depleting in the water bodies of Kashmir Valley which may be dangerous for their existence. It is expected that this book will prove useful in breeding them in captivity and thus protect them from extinction.