What are the three most critical required “nutrients” for high-risk calves who have been on a truck for an extended period? Hay, water, and rest. Alright, those aren’t all exactly “nutrients” per se, but they are definitely REQUIRED. Nutritionists, veterinarians, and feedyard managers could probably argue for a month as to which of the three is the most important and urgent; none the less, they all are both important and urgent.
The rumen thrives on constancy. The animal is designed to keep a steady supply of forage and water flowing to the rumen, a steady amount of waste products flowing out from the rumen, and a steady stream of nutrients from fermentation absorbed through the rumen wall. Cattle that have been off feed and water for a number of hours need to re-start this flow.
Good quality grass or cereal grain hay, long-stemmed, needs to be available for calves to nibble on, along the bunk line and also in a hay feeder. Normally we want to encourage calves to get all their feed from the feed bunk but extremely stressed calves need to feed immediately and there may not be sufficient linear space at the bunk for all calves to eat at once. There needs to be a safe place for small or timid calves to eat hay in peace.
Clean, fresh water needs to be available. A separate additional water tank should be placed along the fence line so that (a) there is room for many calves to water immediately after arrival and (b) there is plenty of water for all the calves. These tanks may need to be re-filled throughout the day depending on demand.
Exhausted calves will want to lay down immediately after arrival. Opinions vary with respect to the urgency of rest. Some experts believe that immediately upon entry to the receiving pen exhausted calves should be gently moved to the feeding and drinking areas, to encourage them to eat and drink prior to bedding down; others contend that 30 minutes of rest prior to feeding and drinking is valuable. Most agree that after feeding and drinking, calves should be allowed an extended rest period prior to post-arrival processing. Some suggest an hour of rest for every hour on the truck. This is a rough guideline.
If pen conditions are wet upon arrival, straw or corn stalks should be put out, on the mounds, to give calves a relatively, dry, clean place to bed down. Regardless, receiving pens should have abundant area per animal, bedding during wet conditions, and shade during hot conditions.
We often place unrealistic expectations on vaccines and antibiotics to prevent disease in high-risk calves. It might be better to focus on these three important “nutrients” first.