PSIX-8 - Supplementing a Natural Citrus Flavonoid Extract (Bioflavex) to Finishing Cattle

Abstract: Finishing cattle are exposed to diets with high amounts of starch and consequently to hindgut acidosis. Usually, antibiotics like ionophores are used to control dysbiosis at gut level. However, natural options are being evaluated as healthy alternatives. Flavonoids are well known as antibacterial agent, being an interesting alternative to antibiotics. The aim of this experiment was to evaluate the performance of finishing steers supplemented with monensin compared with citrus flavonoid extract (Bioflavex). Steers (n = 48; 214.3 kg live weight; LW) were assigned to two treatments: Monensin (MON; 30 g/tn DM) and flavonoids extract (FLAV; Bioflavex, Spain; 400 g/tn DM). Animals were allocated in 6 groups (3 pens/treatment; 8 animals/pen). Pen was considered as the experimental unit. Transition diet was offered from d 1 to 21 (CP 18% , starch 40.6%) whilst finishing diet from d 21 to 86; (CP 10.6%, starch 47.8%). The LW was registered at 0, 21 and 86 d. The DMI was estimated by difference between offered and refusals. Ruminal and feces pH were recorded (rumen liquor samples were obtained by ruminocentesis). Data were analyzed by proc mixed (treatment and time as fixed effects; pen as random). Differences were stated when P< 0.05. Only DMI was different between treatments, being FLAV greater than MON (6.68 kg/d vs 6.45 kg/d for FLAV and MON respectively; P< 0.05). No differences were found in terms of daily gain (1.355 kg/d vs 1.294 kg/d for FLAV and MON respectively; P >0.05), final weight (FLAV 331.6 kg vs MON 324.8 kg; P >0.05), neither conversion (4.95 kg/kg vs 4.98 kg/kg for FLAV and MON respectively; P >0.05). Rumen and feces pH did not differ across treatments (P >0.05). According to our results, a citrus flavonoid extract showed a similar performance comparing to monensin, being a potential alternative to antibiotics.