Performance effects of extended feeding of monensin to Eimeria-challenged tom turkeys.

Abstract The benefits of extended feeding of monensin beyond the traditional 8-9 wk of age was demonstrated in a trial in which tom turkeys were fed monensin for either 8, 12, or 16 wk of an 18-wk growout in a step-down program. Four anticoccidial programs were evaluated in the trial: 1) no anticoccidial; 2) monensin at 75 g/ton for the first 8 wk followed by no anticoccidial; 3) monensin at 75 g/ton for the first 8 wk, reduced to 67 g/ton until 12 wk, followed by no anticoccidial; and 4) monensin at 75 g/ton for the first 8 wk, reduced to 67 g/ton until 12 wk, further dreduced to60 g/ton until 16 wk, followed by no anticoccidial. In the presence of an induced coccidial challenge, turkeys fed monensin for the first 8 wk (Treatments 2, 3, and 4) were significantly heavier with improved feed efficiency compared with turkeys not fed monensin. Extended feeding of monensin beyond the traditional 8-9 wk of age (Treatments 3 and 4) resulted in significantly heavier body weights and significantly improved feed efficiency at 18 wk of age.