The age of Kali or Shaktism we do not have men who are desireless in their actions, who can subdue their minds and give up all works to become ascetics and who could remain chaste at heart even in the company of women. Hence with the passage of time the sacrifice became increasingly elaborate, and priests became highly skilled specialists. The meaning of the sacrifice also changed. As the socio-economic structure of the Hindu communities became increasingly complicated, so did the ritualistic practices and their implications. Sacrifice in the form of bloodshed became an integral

For example in the vedic age one might find instances of Ashwamedh Yajna or Horse sacrifice and also Goumedha Yajna or Cow sacrifice. Horse sacrifice was one of the most important royal rituals of Vedic religion, described in detail in the Yajurveda. The Ashvamedha could only be conducted by a king. Its object was the acquisition of power and glory, the sovereignty over neighbouring provinces, and general prosperity of the kingdom.The horse to be sacrificed must be a stallion, more than 24, but less than 100 years old. Pusyamitra Sunga is said to have performed the Ashvamedha rite after he toppled Mauryan rule in 185 BC. In the Mahabharata, the sacrifice is performed by Yudhishtira and in Ramayana it was performed by Rama.

Cow sacrifice was also common at one time but as time passed people started realizing the importances of these two animals in their socio-economic life. Hence in the later age these sacrifices were banned and cow is considered as a holy animal in Hinduism. Ajmedha or goat sacrifice continued to be sacrificed from ancient times till date. Goats are most commonly used and may have the connotations of being the scapegoat of all the sins of the family who are patrons of the worship.

Literally speaking goats, sheep and deer are considered as symbols of kam or extreme greed, passion and lust. On the other hand a buffalo is most probably considered as a symbol of anger. Ritual killing of various kinds of birds like rooster, duck, pigeon are usually common among tribal communities. They prefer these animals as objects of sacrifice probably due to their lower economic conditions.
Since sacrifice or bali is symbol of power, kings and rich zaminders of early ages showed their might practicing such rituals in order to fulfill their long cherished desires. One might get instances of human sacrifice in this regard. The scene of blood creates a sense of excitement/hostility inside ones mind which was perhaps essential for the kings and the princes as well as the zaminders who were used to violence and killings. Followers who practiced Virachar system of Tantrism encouraged human and animal sacrifice. They did this in order to arouse the feeling of valour in them.
In the Vaishnav cult sometimes sacrifice of vegetables or fruits like gourd, pumpkin, sugarcane, betel nut, ginger, cucumber, etc are seen. The Vaishnav cult does not encourage animal sacrifice and bloodshed as the followers of this cult are the worshippers of ahimsa or non-violence.
It is to be noted that whatever things or animals are sacrificed, they had to be in a perfect state with no injuries or deformities in their body. Earlier when human sacrifice took place, the worshippers preferred handsome children or youths as the objects of sacrifice. So was in the case of animal sacrifices.
To attain Moksha or pure salvation of the soul, sacrifice is essential but not at the cost of other innocent lives. One should sacrifice his or her inner evil traits of passion, greed, anger, ego, avarice, and emancipate oneself from any bondage.