Is it incumbent upon the slaughterers helper (assisting in holding the animal) to recite “Bismillah, Allah-o-Akbar” ?
It is not necessary for the person who renders help in holding the animals legs, head, horns etc. to recite the takbeer. But if the helper holds the knife together with the one who slaughters and assist him in the use of the knife, such an assistant is compelled to recite Bismillah. If either of them deliberately omits to recite or thinks the recitation of one of them is sufficient, the slaughtered animal becomes unlawful.