Effect of monensin on weight gain and bloat prevention in steers feeding on lucerne pasture

An experiment was carried out, from October to December 1992, in order to evaluate bloat prevention and weight gain of steers. Animals were on an alfalfa pasture with previous records of bloating. Two groups of 20 selected steers were randomly divided into two separate fields. The treated group, with an initial body weight of 251.5 +/- 28.0 kg at the beginning of the experiment, received capsules containing 32 g of Sodium Monensine. The control group weighed 253.6 +/- 21.2 kg at the time and received no capsules. After 75 days the average weight increase in the treated group was 73.5 kg, while the control was 60.2 kg. To evaluate the degree of bloating, animals were divided into three categories: A) nonaffected; B) bloated; C) severely bloated. It was concluded that the Sodium Monensine treatment had a positive effect on bloating prevention and the treated steers gained 22% more weight than the untreated.