Does "Yode'a Tzadik Din Dalim" come to teach how Hash-m made a dog's digestion?

Maharsha: Primarily, it teaches that a Tzadik knows to give Tzedakah to Aniyim; the Seifa says "Rasha Lo Yavin Da'as" - to give to an Oni." However, "Din" is not so appropriate according to this. Therefore, we expound that Tzadik is Hash-m. He knows the Din of Dalim - dogs, that Din is on them, that their food is sparse, unlike birds and fish.

Why is a dog's food sparse?

Rashi: Man does not have mercy on it, to feed it liberally.

Iyun Yakov: Hash-m made it sparse, for dogs are brazen - "v'Ashir Ya'aneh Azus." If dogs were rich (NOTE: they would be far more brazen, and) the world could not bear them. This is why poverty is proper for Yisrael (Chagigah 9), to weaken their audacity. A Chacham does not become poor, for Torah weakens his audacity (Beitzah 25). "Hash-m Oz l'Amo Yiten Hash-m Yevarech Es Amo va'Shalom" - Oz is Torah. Due to this, Yisrael will not become poor, and there is Shalom - when barley is finished from the barrel, quarrels come in the house (Bava Metzi'a 59a).

What was the question 'how long does food remain in the innards, and it is Tamei?'

Rashi: If an animal ate Tum'as Mes, while it is alive, the Tum'ah is Balu'ah (swallowed), it is not Metamei. If the animal died, for how long is the Tum'ah intact inside, and Metamei?

R. Shimshon (Ohalos 11:7): The three days are between eating and dying.

How do we learn that it is proper to throw meat to dogs?

Rashi: We said that Hash-m is concerned for a dog's food.

Maharal: Hash-m put special Hashgachah on a dog.

Should one throw meat even to a dog that is not his?

Maharsha: Yes; we infer so from Rashi. If it was his own dog, we need not learn from the verse that he must feed it! We said that one feeds his dog on Shabbos, for he is obligated to feed it! In Bava Kama 83a we permit raising dogs on a chain, or near the border.

Rav Elyashiv: It is permitted on Shabbos, even if it ate earlier today, lest it not eat for the next three days.

How much is an ear's worth?

Rashi: A small amount, like the size of its ear.

Maharal: One should not give to it much, like the Gemara says, lest it follow him. Also, this is wasting food if he gives to it much. (NOTE: i.e. l'Chatchilah, food proper for people, we do not feed it to animals. Maharal assumes that he feeds to it Kosher meat - it is not common for a Jew to be carrying Tereifah or Neveilah meat. - PF)

Why should he hit it immediately after?

Rashi: This is lest it regularly seek food from him.

Why is a pig the wealthiest creation?

Rashi: It eats anything. It finds what to eat, and people feed it much.

Why does Rav Papa teaches that a dog is the poorest creature, and a pig is the wealthiest?

Divrei Eliyahu: Hash-m gave the entire Torah, but some Lavim people are very careful about them, and others not. If one sees Ploni eat pork, he will not make a marriage with him, and he is ashamed to talk to him. There is a more severe Lav that is light in people's eyes, e.g. Leshon ha'Ra. They do not take the Isur seriously. The Lav of Chazir is 'rich' - all fear it. The Lav of Leshon ha'Ra is poor - no one fears it. Anyone who speaks Leshon ha'Ra, it is proper to cast him to the dogs (Pesachim 118a). This is because he always barks, like a dog. A dog is the poorest, i.e. the Lav of Leshon ha'Ra, and the Lav against eating a pig is the wealthiest.