291 - Weaned Holstein Calves Fed an Experimental Botanical Extract Alone or in Combination with an Eubiotic Product

A botanical extract (BE; garlic oil, anise oil, cinnamaldehyde, rosemary, and thyme blend) has been shown to enhance dry matter intake (DMI) and gut health, while eubiotics (EU; lactobacillus acidophilus fermentation product), has been shown to improve gut health and growth performance of growing Holstein calves. The hypothesis was the combination BE and EU could be synergistic to post-weaning neonatal calf growth performance. Seventy-seven (77) Holstein bull calves from a previous milk replacer trial were randomly assigned to 1 of 4 treatments using a 3 wk experimental period. Treatments were: 1) Control: Calf starter (CS) without BE or EU; 2) BE: CS with 275.6 g/ton of an experimental BE (Adisseo North America, Alpharetta, GA); 3) EU: CS with 0.22% EU (RumaCell DF 5G; Pacer Technology, Murtaugh, ID); and 4) BE&EU: CS with added BE and EU. The 22% crude protein CS was a mini-pellet and fed for ad-libitum consumption with amounts fed and orts recorded daily. Calves fed EU demonstrated greater (P < 0.05) body weight (BW; 81.3, 80.8, 84.8, and 84.2 kg for Control, BE, EU, and BE&EU, respectively) compared with calves fed Control and BE with calves fed BE&EU being intermediate and similar (P > 0.10). Calves fed BE demonstrated greater (P < 0.05) average daily gains (ADG; 965.5, 984.3, 1052.8 and 989.1 g/d) compared with calves fed Control with calves fed BE and BE&EU being intermediate and similar (P > 0.10). The DMI (2.19, 2.18, 2.31, and 2.14 kg/d) and feed conversions (0.45, 0.46, 0.45, and 0.45 kg BW gain/kg DMI) were similar (P > 0.10) among calves fed all treatments. Blood urea nitrogen concentrations (14.7, 14.6, 14.9, and 13.4 mg/dL) were similar (P > 0.10) among calves fed all treatments. Feeding a EU improved BW of weaned growing Holstein bull calves, but the BE and EU combination was not beneficial for enhancing growth performance.