Does the perception of the opening takbeer cease to exist if a worshiper perceives it, then his ablution is nullified and he leaves the prayer, and then returns?

If a worshipper's ablution (wudu) is nullified during prayer, he must leave the prayer, perform ablution, and recommence the prayer with a new opening takbir (ihram). What he completed before his ablution was nullified is not counted as part of his prayer, but he will be rewarded for it. Thus, if ablution becomes invalid during prayer due to an impurity (hadath) or other reason, he will be rewarded for what has passed if it became invalid through no choice of his own. And if a worshipper's prayer becomes invalid due to an excuse after, for example, two rak'ahs, he will be rewarded for them with the reward of prayer, not merely for recitation and remembrance.