Evaluating performance of beef cattle consuming a supplemental probiotic-prebiotic during the first 21 or 42 days after feedlot arrival

Abstract

The objective of this study was to evaluate the effects of a supplemental probiotic-prebiotic blend (P-PB) on newly received beef cattle during the first 21 and 42 d after feedlot arrival. Crossbred steers (n=258; BW = 250 ± 11.4 kg) were received at the Texas A&M AgriLife Research Feedlot in Bushland, TX. Steers (n=240) were stratified by average initial BW (d -1, d -0) and allocated to 1 of 2 weight blocks and 1 of 3 dietary treatments. The control treatment (CON) received a pellet without P-PB. Treatment 2 received a pellet with P-PB from d 0 to 21 and then the CON pellet from d 22 to 42 (P-PB21). Treatment 3 received the P-PB pellet from d 0 to 42 (P-PB42). Following the 42-d receiving period, treatment pellets were removed and replaced with steam flaked corn for the remainder of the finishing period. If DMI was < 6.35 kg/steer daily, the P-PB pellet was included at 8.75% of the diet. If DMI was ≥ 6.35 kg/steer daily, the P-PB pellet was included at 6.25% of the diet. Body weight was measured on d 21 and d 42 of the feeding period. Statistical analysis for the randomized complete block design was analyzed using SAS 9.4. Pen was the experimental unit with 10 per treatment. There were no treatment effects between d 0 to 42 for body weight (BW), average daily gain (ADG), gain to feed (G:F), and dry matter intake (DMI) (P ≤ 0.99). No differences were observed for percent morbidity or mortality (P ≤ 0.65) from d 0 to 42. P-PB did not impact LM area, rib fat, marbling score, USDA QG or YG (P ≤ 0.99), while CON had a greater DP (P ≤ 0.05) and tended to have a greater hot carcass weight (P = 0.09). While results remained similar between treatments, there were no negative effects on cattle health and performance during the first 42 days after receiving.