In addition to
SCOWL
From Oray's deleted post, I found 3 more. Two contain 3 animal names and one contains 4.
COATI, a South American animal that also contains:
C-AT- (Cat)
--A-I (Ai, a type of sloth)
ASPIS (ancient shield) contains:
ASP-- (Asp, a snake)
A--I- (Ai, a type of sloth)
AS--S (Ass, a donkey)
KRAIT (a type of snake) also contains:
-RA-T (Rat)
--AI- (Ai, a type of sloth)
K--IT (Kit, short for kitten)
EDIT: Found another one with 4 animal names:
BRANT (a type of goose) also contains:
B-A-T (Bat)
-RA-T (Rat)
--ANT (Ant)
And another one that contains 3 or 4 animal names:
BOART (variant spelling of bort, a low-quality diamond) contains:
B-A-T (Bat)
BOA-- (Boa, a snake)
BOAR- (Boar, a wild pig)
BO--T (Bot, the larva of the botfly)
And if 'bot' counts, there are other words (like 'boast') that contain 3.
As for a simple one,
CROWD contains:
CROW-
C-OW-
C-O-D
[There's also 'scrow' (crow-cow-sow), but it's obsolete]