No, it is not, it's a word from either Russian or Belarusian and as such it might be used in some regions of Ukraine. In Ukrainian the proper term is худóба. UPD: I've looked in a dictionary, and in fact it does list скот among other synonyms, but худоба is definitely a correct term.
Скот (< Proto-Slavic (s)kъptъ) is a pan-Slavic word from Indo-European origin - it doesn't belong to any particular language. Originally it meant a "head of cattle" and is related to the English 'head' / German 'haupt'. It may also be related through an ablaut with the verb коуповати "to buy, purchase goods"