When the Torah commanded us to refrain from labor on, it also commanded us to rest our animals. An animal may not perform labor on behalf of its owner on (Shemot 20:9; 23:12). The fifth perek of Massekhet, which begins on today’s daf does not clarify the full extent of the mitzva to rest one’s animal; it deals extensively with preventing one’s animal from performing just one prohibited labor, the labor of carrying out on. The halakhot of carrying out are cited first primarily because one must be aware at the onset of which vessels and equipment may be left on the animal on and which items must be removed.
The central issue discussed in this chapter is: Which of the items that one customarily places on an animal – a saddle, reins, and chains – are considered a garment for the animal? If they serve the animal’s needs, it is permitted to place them on the animal.
Which items are considered a burden, and it is prohibited to place them on the animal?
The assumption is that any item typically used for protection of the animal is considered to be serving the animal’s needs, and leaving it on the animal is permitted. Therefore, it is necessary to ascertain the means of protection standard for each animal and whether or not excessive security measures constitute a burden.
The first Mishna in the perek asks:
With what may an animal go out into the public domain on and with what may it not go out? A camel may go out on with an afsar, and a naka may go out with a ḥatam, and a luvdekim may go out with a perumbiya.
What is the meaning of naka with a ḥatam? Rabba bar bar Ḥana said: A white female camel with an iron nose ring. And what is the meaning of luvdekim with a perumbiya? Rav Huna said: A Libyan donkey with an iron halter.
The Gemara explains that an object designated to protect the animal or to prevent it from fleeing is not considered a burden, and these examples fall into those categories.