The opening half saw both Ahoghill rinks register three-shot wins.
The Towers rink skipped by Darren McCullough scored two shots on the first end but the next three ends cost the District League champions eight shots, although they had got it back all square by seven ends. William Morrison's Ahoghill rink then scored a pair of twos and lost a single on the last end.
On the other mat, Andrew Morrison's rink won just four of the 10 ends, but scored '3' of two of them against David McCullough, who managed just five singles.
After the break, David Morrison's rink scored a 10-shot win against Ivan Craig, aided by a '4' on the seventh end and a '3' on the second.
James Gaston's rink made a bold attempt at overturning Towers' deficit with a 17-3 win over Tom Morrison, helped by a '5' on the last end.
First Ahoghill 36, Towers 34: W Morrison 12, Darren McCullough 9; A Morrison 8, David McCullough 5; T Morrison 3, J Gaston 17; D Morrison 13, I Craig 2.
A collection of almost 300 was raised for the Ulster Cancer Foundation, with Mrs Betty Millar present to receive the cheque from Bryan Magrath, the donor of the Shield.