Chullin 137 - First Fleece - Only Wool of Sheep, not of Goats
We learned that the kohen's gifts are strict: they apply to all animals, many or few, while the first fleece is more lenient. But there is yet another stringency: kohen's gifts do not apply to a sick animal ( terefah ), why is this not mentioned? - Because the author of our ruling is Rabbi Shimon, who says that the first fleece also does not apply to sheep that are terefah either - because the Torah used the same word "give" here and in discussing animal tithe; the tithed animal "walks under the rod" and terefah sometimes cannot walk.
The first fleece is given to a kohen only from sheep, because the word "shearing" used by the Torah only applies to sheep, and goat hair is "plucked." This meaning of the word "shearing" becomes clear from the book of Job: "from the fleece of my sheep he warmed himself."
"Any amount" of fleece that the Sages require to be given to a kohen was only said in contrast to Rabbi Yose's eight pounds, but really they mean about five times less than that, and there are four opinions about their opinion.
Art: Paolo Veronese (Caliari) - Portrait of a Man in a Fur Coat