From the Dagestan and Chechnya entry in The Penguin Companion to Food:
Still on the topic of sheep, Chenciner observes that both main types of sheep are eaten: the plains sheep with fat tails, and the mountain sheep without. He quotes from Thomas Love Peacock (1823):
The mountain sheep are sweeter,
But the valley sheep are fatter,
We therefore deemed it meeter
To carry off the latter.
Peacock… hmm, was peacock ever eaten? Sure it was! “It was so greatly prized in classical Rome as a bird to serve at banquets that Cicero (1st century BC) said that it was ‘daring’ to give a banquet without one.” But
Witteveen…, in an essay which is the best source of information on the subject, observes that peacocks seem not to have made good eating. He cites modern experiments which confirm the view expressed by some authorities in premedieval and medieval times that the flesh of a peacock is tough and needs to be hung and then given a prolonged cooking if it is to be edible. Implicit confirmation is provided by the fact that when the turkey arrived from the New World it rapidly displaced the peacock… A full explanation of its high status at banquets for 1,600 years and its subsequent eclipse within a century would have to take into account more factors than can be considered in this brief note.