No, you dont have to weigh each bird. Just the average weight will be fine. If you're going to use the safeguard liquid goat wormer, the dosage for a 5 pound hen is 1.25ml given orally.There has got to be an easier way. So you have to hold each bird and weigh it, 60 times? That’s just not plausible.
The valbazen would be best. It's a 500ml bottle and will last you a long time, also less to to dose.... 1/2ml.