Although small animals may not be kept in Eretz Yisrael, however they may be kept by a butcher for thirty days prior to the day of the market but after the market is over the animal may no longer be kept even if the thirty days are not up.
R. Gamliel says that a person may keep small animals even in Eretz Yisrael as long as he keeps them tied to the posts of his bed.
A shepherd who raised small animals in Eretz Yisrael and he wants to do Teshuvah is not obligated to sell all of his animals at once; instead he may sell them off one by one.
A Ger who inherits pigs or dogs is not obligated sell all of the animals at once; instead he may sell them off one by one.
If someone vows to buy a house or to marry a woman in Eretz Yisrael he is not obligated to do so immediately, instead he may wait until he finds the right one.
Just as it is forbidden to raise small animal so too it is forbidden to raised small Chayos.
R. Yishmael says that it is permitted to raise small dogs, cats, monkeys and weasels in Eretz Yisrael.
R. Yehudah says in the name of Rav that it is forbidden to raise small animals in Bavel just like it is forbidden in Eretz Yisrael.
R. Huna says that it was only forbidden to raise small animals in Bavel after Rav came to Bavel. (1)
Rav displayed respect to Shmuel and would not enter a room in front of Shmuel because of an incident in which he cursed him.
Shmuel displayed respect to R. Asi and would not enter before him while R. Asi displayed respect to Rav and would not enter in front of him.
Rav says that it is permitted to kill a white cat and it is forbidden to keep it and it is permitted to steal it and if it is lost even the hide doesn't have to be returned.
The Tzibur shall blow the Shofar even on Shabbos when pleading to Hashem regarding a plague of dry Shechin.
When the Tzibur pleads to Hashem regarding a plague of wet Shechin, locust, flying creatures, snakes or scorpions the Shofar is not blown.
Mar Zutra says that a Talmid Chacham who doesn't receive Semichah at first will not easily receive it in the future.
R. Ashi says when bad things occur to a person his situation doesn't easily change.
Someone who buys a house from a non-Jew in Eretz Yisrael may have a Shtar written by a non-Jew even on Shabbos. (3)
If someone buys a city in Eretz Yisrael he is forced to buy a road in all four directions for the purpose of settling Eretz Yisrael.
A BIT MORE
1. After Rav came to Bavel many more people settled there because of the existence of his Yeshivah and therefore it was forbidden to raise small animals because of the possibility that they will stray into people's fields.
2. A black cat that was born from a white cat that was born from a white cat is also forbidden, however a black cat that was born from a white cat that was born from a black cat is a Safek.
3. Even though it is forbidden d'Rabanan to ask a non-Jew to do a Melachah for you on Shabbos in this case the Rabanan permit it for the sake of settling Eretz Yisrael.