(Mishnah): One who makes an animal pen in his field in Sheviis, he should enclose an area of a Beis Seasayim (100 Amos by 50 Amos) with 4 fences and move his animals to there. When it is filled with manure, he should remove the fences on 3 sides and leave the 4th standing and transfer those 3 fences to the other side of the 4th fence and enclose it from the other side, thereby ultimately having a pen of Beis Arbaas Se'im (200 Amos by 50 Amos).

(R. Shimon ben Gamliel): He may do this in Beis Shemonas Se'im (400 Amos by 50 Amos).

If his entire field was an area of Beis Arbaas Se'im, he should leave a small part of it without a pen because of Maris Ayin and he should take manure from the enclosure (rather than leave it there), but afterwards, he can put it in his field in the way of those that apply fertilizer.

(Gemara) Question (Mishnah later on): If a field had its thorns removed, it may still be sown in Sheviis. If it was thoroughly plowed or used as a pen, it may not be sown after Sheviis...? (Our Mishnah even ideally permitted making a pen.)

Answer (R. Yona): Our Mishnah was discussing when he merely wishes to stand his animals there, but he is not trying to fertilize. The wording also indicates this, as it implies that he merely wishes to stand his animals there, but he doesn't intend to fertilize.

Tosefta: One may construct an enclosure from any material (that can contain the animals) - from mats, straw and stones and even using three parallel horizontal ropes. He may construct another enclosure, as long as he distances it the width of an enclosure away. And in that space (between the enclosures), he may milk, shear and walk the sheep (with no concern if they making droppings there).

Baraisa (R. Shimon ben Elazar): He may thrust a peg into the ground and make the enclosure (of Beis Seasayim) on each sides of it, making Beis Shemoneh Se'im (8 Se'ah),

One may not even tell a gentile to make a pen on Shabbos, Yom Tov or Chol Hamoed, even if he does it as a favor. He may not appoint a gentile guard (if the sheep came there on their own, to prevent them from leaving). The gentile may not move the sheep from place to place in order that they make more droppings. If the sheep came on their own, he may not direct them into the owner's field.

If gentiles are working for him on Shabbos or Yom Tov (for example, if he hired them to do a job over a period of time etc., known as Kablanus), if they come to make a pen, he may assist them, appoint a guard, or move the sheep around. If the sheep came there on their own, he may direct them.

Baraisa (R. Shimon ben Gamliel disagrees): On Shabbos, he may have a gentile make a pen as a favor; on Yom Tov he may pay the gentile by supplying him food; and on Chol Hamoed, he may even pay him money.

(Baraisa): If one rents a sheep (for its wool or milk), he may not 'mena'er' it.

What is the meaning of 'mena'er it'? Moving it from place to place (in order that it make droppings; it is prohibited since he is causing a loss to the owner, who has rights to the droppings as fertilizer). This is discussing when he rented it for a short period of time, but for a long period, it is permitted, except on the last day of the rental.

(Rav Chuna citing R. Nachman bar Yaakov): If a person goes to relieve himself and he is unable to do so, he should walk from place to place.

(Rav citing Mar Ukvan) The vegetable called Chafrisa is good for constipation.

Question (R. Chiya bar Ba): Before the workers stop working, is it permitted to take manure out of the enclosure and put it in his field in the way of those that apply fertilizer? (The Gemara leaves this question unanswered.)