Effects of short-term feeding of clenbuterol on nitrogen retention, performance and meat quality in finishing pigs

Abstract

S U M M A R YAn experiment using 30 Belgian landrace finishing pigs was carried out, in 1989, at the University of Leuven, Belgium, to examine the effect of clenbuterol in the diet (1 mg/kg) on the repartitioning of nutrients and body composition. Clenbuterol was administered for 20 days preceding the week before slaughter. Fifteen animals were fed a diet containing the /?-agonist, and 15 other animals served as negative controls. Weight gain, feed conversion and N utilization improved during /?-agonist treatment. Removal of clenbuterol from the diet rapidly increased blood urea concentrations, indicating immediate, less efficient, N utilization. In the week before slaughter, the animals did not lose the extra weight gained in the period of clenbuterol feeding. Backfat thickness at slaughter was reduced by 15% in the animals fed clenbuterol. Dressing percentage and post mortem pH decline, colour and water-holding capacity in ham and the longissimus dorsi were not affected by dietary treatment. Clenbuterol was not detected in renal fat and the longissimus dorsi at slaughter.