THIA CAL liquid B1 calcium supplement uses a blend of all natural ingredients in a palatable liquid formula to relax horses that suffer from nervous conditions and will not test positive. Frequently, the cause of nervous behavior in a horse is related to treatable nutritional deficiencies. Specifically, a deficiency of Thiamine, or Vitamin B1, is the most common culprit. Horses with low levels of Thiamine will often act irrationally, struggle to keep weight on, and lack focus in competitions.