Animal cover having a temperature altering device

System for temperature modification comprising: - a blanket (2) with a size and sized to cover a horse; - First and second pockets (16B, C, D, E) arranged on a lower side (4) of the blanket (2), each of which has a cavity that includes a device for changing the temperature can I extract (18), wherein each of the first and second pockets can be placed freely in the blanket using fasteners hook and loop; and that the first pocket (16B, 16C) has a first size and the second pocket (16D, 16E) has a second size that is different from the first size; and because a skirt (12) is coupled to the blanket (2), wherein the skirt (12) includes another pocket (16F) positioned to deliver a regime change in temperature to a joint babilla horse.