You don't want to see ribs sticking out on the heifers. They really need to be in good condition. If necessary, they should be separated from the other cows and eating well.
For example, a rancher can use tech cloth and rock to create a hardened crossing or feeding area in what had been wet spots. OSU Extension has materials available to explain how to stabilize those areas.
Think about the amount of energy it takes a person to walk across a nice, dry, grassy area versus a field of mud. The same is true for livestock. Also, livestock may be huddled up under a tree to escape the rain and aren't coming to the feeding area. It may be a challenge to get enough nutrients into them.
It's a good year for moving sheep into barns for lambing. Remember to keep the sheep in clean, dry pens, free from drafts. There needs to be good ventilation to avoid pneumonia. We've just been spoiled in recent years by fairly easy winters.