No Hay to Free-Choice Hay in One Day?
Here we are in the transition heifer housing. Heifers at this dairy move from hutches into small outdoor group pens (10 calves) where they continue their ration of free-choice pelleted grower concentrate (18% protein) and water.
Then they come into this transition heifer barn - starting at one end and in several months moving to pens in the other end. On this in-coming end the ration continues with free-choice pelleted growth concentrate and water AND free-choice hay.
Yes, the heifers go from no hay to free-choice hay in one day.
By my visual inspection I cannot see any significant growth until the heifers have been in this barn for nearly a month. Today there is a small amount of coughing among heifers in the youngest pens.
What is going on in this situation?
These youngest heifers appear to be enjoying the hay today - all I can think of is the lack of the appropriate fiber-digesting microbes in their rumens necessary for breaking down all this fiber. Hay goes in the front, turns brown, goes out the back without any significant nutrition received.
Net result of hay intake the first week or two? Fills up the very small rumen displacing the grower pellet. Available energy and protein drops drastically - growth flat lines - some calves show symptoms of bovine respiratory disease.
Recommended introduction of hay at this dairy
1. For at least a few days after moving into this barn continue same ration used in outdoor pens.
2. For the first week or ten days for feeding hay, limit hay to what the heifers will clean up in an hour. By the way, this dairy has enough bunk space for all the heifers to eat at one time - good.
3. After ten to fourteen days (time enough for the fiber-digesting microbial population to reach a new balance in the rumen) then move to free-choice hay.