This video will discuss whether it is really necessary to rotate from one ionophore to another.
This practice developed before the discovery of ionophores when the only available anticoccidials were chemicals. At that time, prior to the 1970s, it was often necessary to rotate to another chemical because of the build-up of resistance. However, with the advent of the ionophores eliminating concerns of a resistance and providing long-term anticoccidial effectiveness, such rotation is no longer merited or necessary.
In fact, there is no advantage in rotating from one ionophore to another since they all have essentially the same mode of action. Therefore, the coccidia would not really perceive the difference in this change and there would be no actual improvement in performance of broilers with this change of anticoccidial medication.
In other words, when no change is needed, it is best not to make a change.
Videos 12 – 9 from the series can be viewed here: