“…In the pig, clenbuterol (Jones et al, 1985), cimaterol (Mersmann et al, 1987), salbutamol (Warriss et al, 1990b), and ractopamine all decreased carcass fat and increased muscle volume. Sheep (Kim et al, 1987), steers (Moloney et al, 1990), mice (Rothwell & Stock, 1985), rats (Reeds et al, 1988), and quail (Merkley &Garwood, 1989) all respond positively to various ~i-adrenergic agonists, as evidenced by increased lean body composition. The unexpected improvement in carcass protein content stimulated further research into the efficacy and potential economic benefit of these compounds to enhance efficient meat production.…”