A polyherbal phytogenic additive improved growth performance, health, and immune response in dairy calves

The objective was to characterize the effects of a supplemental Herbal Antibiotics Source (HAnS) on performance, blood chemistry, blood cells, and antibody counts of Holstein calves. Forty calves (initial BW 45.8 ± 7.2 kg) were randomly assigned to treatments: 0, 3, 4, and 5 g d−1 HAnS. The additive improved hip height and thoracic girth. The reduction of starter diet intake among individuals varied greatly, while milk replacer intake increased. HAnS at intermediate doses reduced the cases of pneumonia. It also linearly reduced the blood serum glucose and B-OH butyrate. Urea and monocytes showed a quadratic response, and basophils decreased. HAnS improves calf development at intermediate doses and reduces the incidence of diseases.