ive had this happen many times with the ones that i had and out of multiple groups. i fed them many many different common foods and i had as many as 50 babies eaten at a time out of different trios. i ditched the effort period and i know of quite a few actual breeders that have had the same problems every now and then.
Thats funny, I haven't heard of it happening. I have been breeding them for a while now, and have not experienced this. It seems obvious to me that either something was wrong with the setup, the diet, or that particular line of ASF.