We've never had one like this . We've looked through B.Y.C. posts and only seen a hypothetical guess of another's query stating Mareks . However , according to a vetmd reference site the vet stated that Mareks had to have more than just liver damage . They stated that Mareks would be identified by spotted liver and tumors throughout the carcass . The spotted liver they showed was only spotted white . Our problem is that out of the thousands of chickens we've handled here , processed , etc.... We've never encountered any type of tumors at any level . These spots are different , They have a tip of green . There was absolutely nothing else on any organs within otherwise . It acted just fine as we transferred our batch from grow out house to breeder house . One day later it was mopey . The next day it was used by the others as a toe warmer as some haven't began perch just yet . Any ideas besides Mareks ? As there's no tumors .