1. A method of determining an animal weight, the method comprising: receiving a digital image of a target object, the image comprising a plurality of pixels, the target object being at least a portion of an animal, the at least a portion of the animal disposed in the image according to a predetermined disposition; analyzing at least some of the pixels of the image of animal to determine a perimeter of an outline of the at least a portion of the animal, wherein the perimeter of the outline of the at least a portion of the animal is iteratively determined by obtaining a current outline and subsequently calculating a new outline, the new outline being based upon at least one candidate boundary point from the digital image, the determining being terminated based upon a comparison of the current outline with the new outline; determining an area enclosed by the perimeter; and determining the weight of the animal using at least a quotient obtained by dividing a square of the perimeter by the area enclosed by the perimeter.