353 Neonatal Holstein Calves fed a Pelleted Calf Starter Containing a Botanical Extract and Direct-fed Microbial (DFM) Alone or in Combination without or with Milk Replacer DFM

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 actobacillus 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-d old bull calves were blocked by body weight (BW) randomly assigned one 8 treatments arranged in 2 x 4 factorial using randomized complete block design. Main factors milk replacers (MR) without (Control) with RC added at 5 g/d fed starter (CS) main effect experimental CS being: 1) Control: no additives; or 2) BE 496 mg/kg the (CS); 3) 2.50 g/kg; 4) BE&RC: same rates CS. 25% crude protein basis MR being 22:20 (CP:fat) 2x/day 0630 1800 h along free choice water. Weaning occurred after d 42 for 56-d experiment. No significant (P > 0.10) interactions detected BW, BW gain, intake, total DMI, feed conversion parameters. gain (38.0 39.3 kg Control RC, respectively) similar both MR, (38.7, 39.7, 39.2, 37.2 Control, BE, BE&RC, among all This study demonstrated little benefits when feeding an and/or alone compared Control.