What type of feed do you use for cattle?

This depends on what stage of pregnancy they are in and whether they are still suckling a calf or not.

Cows in their first trimester are often still nursing, and still need plenty of good quality feed to keep the milk flowing. However, during this last three months that the calf is on his dam, feed quality of the cow can be progressively decreased because the calf is relying less and less on his dam's milk than he is on other feed sources like the creep feed he's getting prior to being weaned, grass, and hay. When the calves and cows are weaned, the cows should be put on low-quality feed or pasture to help speed the drying up process.

Cows in their 2nd trimester (after weaning) can be put on lower quality feed or pasture during these next three months. During the winter, this is a good time to get them grazing stockpiled grass or swath graze, since the feed at this time is lower quality than what is needed for nursing a calf.

When cows start into their third trimester leading up to calving, feed quality should be gradually increased during these 3 months. If you are still feeding cows on swath grazed fields or stockpiled pastures, you may want to supplement them with better quality hay to help with their increasing nutritional demands during this time. This nutritional incline will continue to climb up until the new calf is around 2 to 3 months of age.

After the calf is born, and the cows are lactating, you will need to feed your cows 50% more than what they eat when not lactating.