During the class I taught at Pennsic 38, someone asked the question of whether we knew if the people in the 4th – 7th centuries raised sheep for wool, milk or food.
At the time, I did not remember reading about how this was determined. In perusing some of my research materials (ok, I was looking through my one notebook) I again came across how an “indication of purpose” was postulated by the relative age of the bones found in a midden heap. We know that the Picts had sheep. We also know that they probably had sheep in their diet based on the presence of sheep bones found. What we don’t know is if they were raising the sheep for meat, milk or wool – with any certainty. It would seem, to modern people, that they would have raised them with multi-purpose in mind – but that may simply be a modern mind-set.
One of the ways “purpose” of the sheep can be determined, is the relative age of the sheep by the bones found. If sheep were being raised predominantly for wool and/or milk, the bones found would be predominantly of older sheep (gender is still an issue given that the bones were not kept separate by gender or even by ‘single sheep’). If the sheep were primarily being kept for meat, the relative age of the sheep bones would be from younger animals – lambs or yearlings.
Early archaeological reports only kept records of the percentage of occurrence of sheep bones versus cattle, deer, pig, goat, etcetera. This makes answering the question of “purpose” of the sheep kept an elusive one to answer with any authority. Much like many shepherds today, some were no doubt raised for their wool, milk or meat. Some could have been raised for multiple purposes in the same flock.
So, the answer here is – we don’t know for sure either way. We can only guess.