Ruminant farmers most times try to find out the recommended place where they can source their feeds. Well as for forages, they are readily available everywhere. However, for concentrates, feed-mills and already existing farmers should be contacted for link.
A good feed formula could be got from your consultant in case you need one. In sourcing your feed however, you must be sure of the quality of the feeds from that source otherwise you will be exposing your animals to diseases.
See also: For how long can Ruminant Animals be starved? Find out