As far as the burning of a haystack and damages how far can you extend that to a house. can you say the animal would be liable for everything in the house.
Dear Jeff,
If a person causes fire he is responsible for its damage, except when Tamun (hidden) applies, which is Patur. Tamun is discussed at length in Bava Kama 61b-62a. Normal contents of a house are not Tamun and he must pay.
You mention "the animal." If an animal causes fire there are many details concerning when there is full pay, half or nothing. (Basicly the owner is liable for the house and its contents as much as the haystack.) See Baba Kama 22a at length.
All the best,
Reuven Weiner