Few comments since this topic is as perennial as the AIT issue among internet H -- of course you may not like it, so don't @ me. The domesticated Bos was a central animal for the subsistence of the Indo-European pastoralists on the steppe. It was also a major domesticate for the

the pre-IE Indian peoples like the Harappans and the neolithic Ash Mound culture of southern India (i.e. the bUti-palli/halli-s; early Dravidians?). What is clear is that these pre-IE & circum-IE entry peoples of India consumed the flesh of cattle. However, it is like the female

animal (henceforth cow) was also valued for milk->curds/cheese(?) among both the Harappan and Ash Mound peoples. The former probably also used them as draught animals. The situation was similar with the IEans on the steppe with their version of Bos cattle playing a major role in

food (both diary and flesh) and as draught animals. Given their value for the IEans, the idea of the protection of cattle was central to their culture (independently of them consuming their flesh). Thus, the cattle raids& countering such were very central to their imagination.

Hence, we may infer that the concept of cattle-protection, emerged entirely independently of their consumption among the steppe IEans. For a IEan king whose wealth was animal herds such protection was a central role. Hence, the ideal of go-pAlana emerged long before beef-taboo.