Govatsa Dwadashi fast is observed for the long life of the son. According to religious belief, Bach Baras or Govatsa Dwadashi festival is celebrated every year on Bhadrapada Krishna Dwadashi. The other names of this festival are Bachha Dua and Vasu Dwadashi or Bacch Baras

According to Padma Purana, the four Vedas reside in the mouth of the cow. Lord Shankar and Vishnu are always seated in his horns. Kartikeya in the stomach of the cow, Brahma in the head, Rudra in the forehead, Indra in the front of the horns, Ashwini Kumar in both the ears, Sun and Moon in the eyes, Garuda in the teeth, Saraswati in the tongue, All the shrines in the apana (anus), urine- There are Ganga ji in the place, Rishi Gana in the follicles, Yamraj in the back, Varun and Kuber in the south side, Mahabali Yaksha in the left side, Gandharva in the mouth, snakes in the front of the nostrils, Apsaras in the back of the hooves.

On this day, the real cow and calf are also worshipped.

The Significance of Govatsa Dwadashi is stated in Bhavishya Puran. It is said that Govatsa Dwadashi was first observed with fasting, by King Uttanpada  (the son of Swayambhuv Manu) and his wife Suniti. Resulting the prayers and fast, they were blessed with a son named Dhruv.

On this day both  Nandini and Nandi are considered sacred and is celebrated to thank the cows for their help in sustaining human life and thus both cows and calves are worshiped and fed with wheat products. The worshipers abstain from consuming any wheat and milk products.

on this day only Millet Roti or  Whole millets, sprouted moth, moong, and gram  etc. are used as offerings and knives are not used today by the ladies No food items cut with knife is consumed.