One must keep his animal from working on Shabbat: Shabbat 153a, Pesachim 53a
Determining Law by the Local Custom in selling non-working animals to Nochrim: Pesachim 53a
It is permissible to have an animal do anything which is a Rabbinic prohibition for a friend to do: Shabbat 153b
Selling working animals to Nochrim: Pesachim 53a
Selling damaged/non-working animals to Nochrim: Pesachim 53a
Selling a horse to a Nochri: Shabbat 94a, Pesachim 53a
Putting one's animal in a position where it can graze on uncut grass, or on items which one may not move: Shabbat 122a; Eruvin 79a
"Michamer" - Leading an animal which is carrying a burden: Shabbat 153b, 153b-154b
The above "Michamer" as a Prohibition for which the Requisite Warning is for a Death Penalty, not Whipping: Shabbat 154a