The cow was an important form of wealth in :

In the Rigvedic age, the cow was the primary measure of wealth and the central pillar of the pastoral economy [1][t1]. The Rigvedic Aryans were predominantly pastoralists, and cattle rearing was their most significant economic activity [c1]. The importance of cows is reflected in the terminology of the period; for instance, a wealthy person was known as 'Gomat' (owner of cattle), and the term for war was 'gavishthi', literally meaning a 'search for cows' [c1][t1]. Cows were considered 'Aghanya' (not to be killed) and were frequently mentioned in prayers to Vedic gods as symbols of prosperity and strength [t4][t9][t10]. While cattle remained important in the later-Vedic age, the economy shifted significantly toward settled agriculture and the use of iron, making the cow's role as the absolute primary form of wealth most characteristic of the early Rigvedic period [c4][t9].

Sources

1. [1] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 2: Early India: The Chalcolithic, Megalithic, Iron Age and Vedic Cultures > Pastoralism > p. 24