This textbook provides a detailed view of the relationship between reproductive inefficiency due to developmental disturbance in the reproductive system (Testicular hypoplasia; intersexuality including freemartins) and chromosomal constitution in domestic animals has so far been confined to sex chromosome aneuploidies; mosaicism and chimerism. A major objective of the book is to draw attention to information which may be used directly to increase the efficiency of reproduction of domestic animals. The present work proved a relationship between some of certain pathological conditions, in cattle and buffaloes, and chromosomal aberrations.