Vitamin A in dairy rations

Vitamin A sits within the dairy mineral and vitamin program. The target depends on the herd’s starting conditions, ration, measured status, and vitamin supply in the complete program. The discussion considers how source, premix quality, storage, intake, forage contribution, animal stage, and baseline status affect supplementation decisions. Immune, respiratory, reproductive, and milk outcomes have different evidence requirements and should be monitored with appropriate records. A consistent supply does not by itself prove a production response.