Praziquantel and Ivermectin horse wormer paste

[emrldgrn1]

I just recieved a letter from the state lab saying that the chick i turned in for necropsy died feom roundworm and tapeworm infestation. These chicks are only five months old and have been raised in a horse stall where i figure they picked up eggs. My horses are wormed rotaionally every other month and for tapes in november. That asside, I have a tube of Ivermectin gold which has the praziquantel in it for tapes also. Can i use this on my flock and if so how do i dose it as i have a very large flock of over 50 birds. Other wise, other than all natural, what can i use to treat a mass flock all at once via water that will kill rounds and tapes both?