Question (Rav Kahana): Is a cat Matrif?
Answer (Rav): Even a weasel is Matrif! (All the more so, a cat is.)
Question (Rav Kahana): Is a weasel Matrif? (All this will be explained shortly.)
Answer (Rav): Even a cat is not Matrif. (All the more so, a weasel is not.)
Question (Rav Kahana): Are cats and weasels venomous?
Answer (Rav): Cats are venomous, but weasels are not.
We can resolve the apparent contradictions;
Rav said that even a weasel is Matrif birds;
He said that even a cat is not Matrif large sheep;
He said that a cat is Matrif, but not a weasel, if they clawed kids and lambs.
(The Mishnah taught that a Netz is Matrif small birds, and a Gas (large hawk) is Matrif large birds.)
Question (Rav Ashi): Are other Tamei birds venomous?
Answer (Rav Hillel): Yes.
Question (Mishnah): A Netz is Matrif small birds. (This implies that other birds are not Matrif!)
Answer #1: A Netz is Matrif birds its own size Any other bird is Matrif only birds smaller than itself.
Answer #2: A Netz is Matrif birds larger than itself. Any other bird is Matrif only birds its own size (or smaller).
Version #1 (Rav Kahana): A fox is not venomous.
Question: Rav Dimi reported that a fox was Dores a ewe, and Chachamim ruled that it is Tereifah!
Answer (Rav Safra): The case was, a cat was Dores it.
Version #2 (Rav Kahana): A fox is venomous.
Question: Rav Dimi reported that a fox was Dores a ewe, and Chachamim ruled that it is Kosher!
Answer (Rav Safra): The case was, a dog was Dores it;
(Rav Yosef): A dog is not venomous.
WHICH SCRATCHES ARE MATRIF?
(Abaye): We are concerned only for an intentional scratch with the claw of the foreleg, while the attacking animal is alive.
Inference: We are not concerned for bites, unintentional scratches, scratches with the (claws of the) hind leg, or scratches after the attacker died.
Question: If unintentional scratches are not a problem, obviously we are not concerned for after the attacker dies!
Answer: The Chidush is when the foreleg was cut off before it was withdrawn:
One might have thought that it poisons its victim when it inserts the claw. Abaye teaches that this is not so. Rather, the venom comes when it withdraws the claw.
CASES OF SAFEK DERISAH
(Rabah bar bar Chanah citing Rav): If a lion came amidst cattle, and a claw was found in the back of one of them, it is Kosher.
Question: What is the reason?
Answer: Even though most lions are Dores, a claw (Tosfos - almost) never comes off. Since a claw came off, we assume that the ox came upon this claw when it scratched itself on the wall.
Question: (Tosfos - most) oxen that scratch themselves would not get a claw in their back. We should assume that the lion clawed it!
Conclusion: There are reasons to assume one way and the other. This is like an even doubt, so we leave the ox in its Chazakah. (It is Kosher);
Rav is generally lenient about Safek cases of Derisah.
(Abaye): This is only if a claw is found, but if only a scratch mark is found, we are concerned.
Even when a claw is found, we are lenient only if it is moist, but not if it is dry, for dry claws often come off.
Even when it is moist, we are lenient only if one was found, but if two or three are found like they are positioned on the paw, we are concerned.
(Rav): We are not concerned about Safek cases of Derisah.
(Shmuel): We are concerned.
Both agree that we are not concerned in the following cases;
If we are unsure whether the attacker entered the herd, we assume that it did not;
If we do not know whether a dog or cat clawed the victim, we assume that it was a dog;
If the attacker is sitting quietly among the herd, we assume that it made peace with them;
If the attacker cut off a head, we assume that this abated its rage, and it was not Dores any others.
If the attacker and the herd are both 'talking', we assume that both are afraid of each other. (It was not Dores.)
They argue when the attacker is quiet, and the herd is noisy:
Shmuel holds that they are noisy because one was clawed. Rav holds that they are merely afraid.
(Ameimar): The Halachah is, we are concerned.
Question (Rav Ashi): Rav says that we are not concerned!
Answer #1: Ameimar holds like Shmuel.
Answer #2: Rav retracted and agreed with Shmuel.
Support: The following episode shows that Rav retracted.
Some doubtfully Nidras birds were brought in front of Rav. He sent them to Shmuel to give a ruling. Shmuel choked them and threw them in the river.
If Rav held that they are permitted, he would have permitted them!
Question: If he retracted, and held that they are forbidden, he should have ruled about them himself!
Answer (and rejection of support): Rather, Rav didn't retract. (This is why he did not forbid them himself);
He did not want to permit them, for this is unlike Shmuel, and the question was asked in Shmuel's area.
Question: Why did Shmuel choke them before throwing them in the river?
Answer: He was concerned lest they fly away (and someone find them, unaware that they were clawed).
Question: Why didn't he wait 12 months? (If they lived, this would prove that they are not Tereifos!)
Answer: He was concerned lest someone (accidentally) eat them in the interim.
Question: Why didn't he sell them to Nochrim?
Answer: He was concerned lest the Nochrim sell them to a Yisrael.
Question: Why didn't he just throw them in the wasteheap after choking them?
Counter-question: Why didn't he feed them to dogs?
Answer (to both): He wanted to publicize the law that we are concerned for Safek Derisah.
A goose was bleeding from the neck.
(Rav Ashi): When we are unsure if a scratch came from a dog or cat, we assume that it came from a dog. Likewise, if we are unsure whether it came from a cat or reed, we assume that it came from a reed.
CHECKING A DERUSAH
(Bnei R. Chiya and Shmuel): One must check around the innards of a clawed animal.
Question (Ilfa): Are we concerned that venom can affect the Kaneh and Veshet?
Answer (R. Zeira): From Rav, we learn that we are concerned.
(Rav): One must check around the entire interior of a Derusah, including the Simanim.
Question (Ilfa): How much must Simanim be uprooted to make the animal Tereifah?
Answer (R. Zeira citing Rabah bar bar Chanah): The majority must be uprooted.
Question (R. Ami): If the flesh rotted near a scratch, what is the law?
Answer (R. Zeira): We learn this from (the second law of) Rav Yehudah.
(Rav Yehudah): If an animal was Nidras, if the flesh near the innards turned red, it is Tereifah;
If flesh rotted, we consider that it was removed. (If removal of that flesh would make an animal Tereifah, it is Tereifah.)
Question: What is considered rotted flesh?
Answer (Rav Huna brei d'Rav Yehoshua): If a doctor would remove it, it is like rotted flesh.
(Rav Ashi): Lungs were brought in front of Rav Kahana. They were fine while resting flat, but when hung, they started crumbling. Rav Kahana said that the animal is Tereifah due to Rav Huna's law.
(Rav Nachman): We are concerned for a puncture of a thorn only if the wound extends to the inside (i.e. went past the skin). We are concerned for Derisah if the flesh reddens near the innards;
We are concerned for reddening of the Simanim themselves (but not of the surrounding flesh).