The reason for the 5 day dosage is to make sure to kill the cecal worms (also will kill capillaria worms) which are difficult to kill with one dose. Eggs should be tossed for 14 days from the last dose. Eggs shouldn't be given to any animals because of the possible residual medicine, on the...
Here are some places to order the above dewormers:
http://www.kvsupply.com/valbazen-suspension-16-ounces?CAWELAID=983684421&CAGPSPN=pla&catargetid=320011160000087263&cadevice=c&gclid=Cj0KEQjw3M6oBRDnnIywo5i287ABEiQAXRm7S6zk87uFDds7GVNqywoJo23Zzm_MkxzS7a6dZkcB5A0aAt_28P8HAQ...
If I were you I would use Valbazen 1/2 ml orally and repeat in 10 days, or use SafeGuard Liquid Goat Wormer 1/4 ml per pound for 3-5 straight days given orally to worm the chickens. Heterakis worm is also know as cecal worms. Here is a good article from Merck Manual...
Mareks can cause impaired immunity to many common diseases because of a low white blood cell count. The word "lymphatic" in several areas of the report can be associated with Mareks disease or avian leukosis. Are they doing further studies to check for those? That can cost extra in necropsies...