How does the total egg weight rise after the egg duck is changed?

It is like this: the laying rate of farmers in our company has reached 80% with the feed of other companies, and then the egg laying rate has dropped by nearly 50% as a result of switching to our company's feed. After using it for three days, it has suddenly been replaced by the front feed, and as a result, the egg laying rate has gone up again. How do you explain this? There was no gradual transition in both changes-the egg weight decreased after the change, for two reasons: low levels of energy or protein in the feed. When the material is changed back, the weight of the egg increases for the same reason. Isn't it stressful to change feed?