I claim the ornamental design for an animal collar, as shown and described.
FIG. 1 is a top perspective view of an animal collar showing the new design;
FIG. 2 is a bottom perspective view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a left view thereof;
FIG. 6 is a right view thereof;
FIG. 7 is a rear view thereof; and,
FIG. 8 is a front view thereof.
The broken line features in FIGS. 1 and 2 showing fasteners are environmental subject matter and form no part of the claimed design. The dotted lines in FIGS. 1-8 depict stitching and form no part of the claimed design. All other dashed broken lines shown in the drawings depict portions of the animal collar that form no part of the claimed design.