Kagtihar is the first day of Yampanchak, the five days of Tihar.

Kagtihar is observed by worshipping crows and offering it food. Crow is revered as a bird that helps mankind by conveying messages and balancing ecology by eating worms and insects.

It is also believed, Yamuna sent the invitation for Bhaitika to her brother Yamraj – the god of death – through a crow.

According to Hindu mythology, Yampanchak is observed in memory of the five days Yamraj spent in his sister's place.

Dog, cow and bull are also worshipped during Yampanchak in addition to the crow.
nepalnews.com