An early and accurate diagnosis of pregnancy in cattle and buffaloes is required for successful breeding programs and management of pregnant animals, as pregnant animals require extra care. Pregnancy diagnosis (PD) is also required for obtaining a certificate for the sale and slaughter of animals. PD acts as a tool to determine and understand the success rate of breeding programs like estrus synchronization and artificial insemination. It also helps in identifying the females required to be bred again and/ or treated to get the optimum production from animals. Thus, early PD in cattle and buffalo will help in increasing the income of farmers by increased production, cost-effective management of the herd, and early replacement of the herd. PD methods can be divided into Direct methods and Indirect methods. In direct methods the pregnancy is directly seen or felt as in case of ultrasonography and rectal palpation. While in indirect methods the pregnancy is determined by hormones, proteins or other markers in the biological fluids like blood, urine or saliva. In the past, the pregnancy diagnosis was usually based on the non-return of estrus in the animals.
