356 Neonatal Holstein Calves fed a Pelleted Calf Starter Containing a Botanical Extract and Direct fed Microbial Alone or in Combination

Abstract Botanical extracts (BE; Adisseo North America, Altanta, GA) are known to enhance dry matter intake (DMI) and gut health, while direct-fed microbials (DFM), such as a Lactobacillus acidophilus fermentation product (RC: RumaCell DF 5G; Pacer Technology, Inc., Murtaugh, ID), had shown improved health growth performance of growing Holstein calves. The hypothesis was this combination may be synergistic neonatal calf performance. Eighty 2- 5-day old bull calves were blocked by body weight (BW) randomly assigned 1 4 treatments in randomized complete block design. Treatments were: 1) Control: no additives; or 2) BE added at 496 mg/kg the starter (CS); 3) RC CS 2.50 g/kg with milk replacer (MR) 5 g/d; 4) BE&RC: same rates MR. 25% crude protein basis MR 22:20 (CP:fat) fed 2x/d 0630 1800 h along free choice water. Weaning occurred after d 49 for 70 experiment. Calves demonstrated greater (P < 0.05) BW gain compared BE&RC Control being intermediate similar (63.9, 63.5, 65.0, 59.7 kg Control, BE, RC, BE&RC, respectively). Total experiment DMI (MR+CS) less than remaining (116.5, 114.2, 116.4, 104.9 kg). gain/DMI (0.55, 0.56, 0.57 kg/kg). This that specific should not DFM.