The Mishnah taught (Chulin 105(f)) that one who beat the produce (to thresh it without the use of an animal) is praiseworthy. He is more praiseworthy than who? Than one who treads.

Baraisa: How does one tread (growths of Terumah)? It was taught from R. Shimon that the best thing he can do is to hang Carshinim for the animal to eat while he is working.

(R. Yosi): This shows that if the owner did the same to an animal with Chulin, he does not transgress the prohibition of muzzling an animal while working. (One does not need to feed the animal the same species of food that he is threshing.)

If one uses his animal to thresh legumes and fenugreek, he does not transgress the prohibition of (Devarim 25:4), "You shall not muzzle an ox when it is threshing'', but it is prohibited because of Maris HaAyin (i.e. it looks bad).

One Tanna taught that one only transgresses for produce that is suitable for him (rather than, for example, Terumah or Hekdesh, that he may not use). Another Tanna taught that it even applies to produce that he may not use.

(R. Ba bar Mamal): Our Mishnah follows the opinion that one transgresses even for prohibited produce, as it taught that he should hang baskets on the necks of the animals (in order to avoid the prohibition of muzzling. That shows that if one would muzzle for Terumah produce, he would transgress.) (Note: An entire section in the middle of this entry was wrongly printed here. It's correct location is at the beginning of the 10th Perek.)

"(You shall not muzzle an ox) when it is threshing'' - but not when it's crushing (grapes). R. Eliezer ben Yaakov says that it's prohibited even when crushing (grapes).

(R. Avin): R. Akiva asked R. Shimon ben Yochai to test his response - did the Torah only prohibit muzzling at the time of threshing or even if it was muzzled beforehand?

(R. Shimon ben Yochai to R. Akiva): Just as we expound (Vayikra 10:9), "You shall not drink wine or intoxicating drinks when you come to the House of Meeting'' - must refer to first drinking and then entering, so too the prohibition of muzzling must even refer to muzzling before the threshing begins.