Influence of Ionophore Supplementation on Growth Performance, Dietary Energetics and Carcass Characteristics in Finishing Cattle during Period of Heat Stress.

摘要: Forty-eight crossbred heifers (378.118 kg) were used in a 56-d feeding trial (four pens per treatment randomised complete block design) to evaluate the influence of ionophore supplementation on growth performance, dietary energetics and carcass characteristics finishing cattle during period heat stress. Heifers fed diet based steam-flaked corn (2.22 Mcal NEm/kg) with without an ionophore. Treatments were: i) control, no ionophore; ii) 30 mg/kg monensin sodium (RUM30); iii) 20 lasalocid (BOV20), iv) (BOV30). Both dry matter intake (DMI) climatic variables measured daily temperature humidity index (THI) was estimated. The maximum THI study averaged 93, while minimum 70 (THI average = 79.22.3). Compared controls, did not gain, estimated NE value diet, or observed-to-expected DMI, but tended (p 0.07) increase (4.8%) gain feed. group BOV30 increased (p0.03) (11.8%), feed (8.3%), net energy (5%), observed-to- expected DMI (5.2%). Daily weight greater (7.6%, p 0.05) for than MON30. Otherwise, differences between two treatments feed, statistically significant (p>0.11). Plotting weekly intakes versus THI, observed controls ionophores (CV 1.7%) control 4.5%). Inclusion resulted relatively minor changes characteristics. It is concluded that exacerbate decline DM heat-stressed high-energy diet; contrary, it stabilised favoured efficiency. Ionophore reduced maintenance coefficients around 10%