Comparative animal anatomy – Is it human, or not? In order to be able to distinguish between human remains and those of animals, the forensic pathologist and anthropologist must have some knowledge of comparative anatomy. The following information relates to distinguishing features of the organs of (mainly) food animals - tissues that are frequently confused by the lay public with human remains.
Heart Ox 3 ventricular furrows right/ posterior furrow extends approx 3-4 cm above apex left/ anterior furrow runs parallel to posterior border and ends at apex. There is more fat at the coronary furrow end of the left furrow than at the ends of the other 2 furrows intermediate furrow is shallow and extends down left side of posterior border but doesn't reach the apex 2 bones (ossa cordis) present in the aortic ring comparatively larger than horse and longer (base is smaller) ventricular part is more conical and more pointed than horse fat is firmer than horse fat not as yellow as horse more fat in the furrows compared to horse weight approx 2 kg
Sheep and Goat 3 ventricular furrows bredth at base equals the length no ossa cordis (some older sheep may have ossified cartilage present) firm white fat more pointed than calf's pulmonary artery has a much smaller diameter and thinner wall than calf weight approx 150 g
Pig 2 large and 1 small ventricular furrows right furrow runs obliquely across heart left furrow is parallel with left border intermediate furrow may be present when it is small, situated on left border (may extend to apex) fat is soft, greasy and generally sparse has blunt apex lower end of the left atrium is notched and lower than the right globular shape - broad with blunt apex heart looks twisted as the right ventricle appears to sag weight varies according to size of pig - approx 250 g
Horse 2 ventricular furrows right furrow begins at the coronary furrow just below the posterior vena cava and ends approx 3-4 cm above apex left furrow descends parallel to posterior border and ends at apex no ossa cordis more conical shape than bovine (ox) (less elongated than ox and has bigger base) less fat than bovine fat is oily and yellow weight approx 3 kg
Livers Ox 3 lobes - left lobe is thinner than right + caudate lobe. In younger animals the liver is almost circular in outline - it elongates with age, becoming oval with a narrowing between the right and left lobe gall bladder is pear shaped weight approx 6-7 kg
Calf almost circular in outline remnants of umbilical vein soft texture rounder edges than sheep liver caudate lobe extends beyond the liver edge, unlike that of the sheep
Sheep 3 lobes pointed caudate lobe all edges are 'sharp' deeper division between lobes cigar shaped gall bladder weight approx 500-700 g
Pig 5 lobes Morocco leather appearance (due to large lobules) weight approx 1 kg (larger in sows) pear shaped gall bladder
Horse 3 indistinct lobes triangular shaped caudate lobe middle lobe has 3 finger like projections (actually due to small fissures on the free edge) no gall bladder purplish colour weight approx 5 kg
Lungs Ox left lung - 3 lobes right lung 4 or 5 lobes right accessory bronchus (to apical lobe) trachea - dorsal ridge (approx 50 rings) + large calibre well marked lung lobulations weight approx 2-3 kg
Sheep similar to Ox - small calibre trachea dense leathery consistency indistinct lung lobulation weight approx 0.25 - 1 kg
Pig long trachea (20 cm) dorsal rings of trachea overlap (no dorsal ridge) right accessory bronchus lung substance extremely compressible spout-like larynx (interarytenoid cartilage) distinct lobulations weight approx 0.5 kg
Horse long trachea (80 cm) - large calibre (no tracheal ridge) pointed epiglottis left lung - 2 lobes right lung 3 lobes no distinct lobulations - lobes not divided by large fissures no accessory bronchus much longer than Ox weight approx 2-3 kg
Kidneys
Ox lobulated - 15-20 lobes 15-25 renal papillae no renal pelvis left kidney 3 sided (open or free) right eliptical and fixed red/ brown colour weight approx 300-350 g
Sheep bean shaped dark brown smooth has a renal pelvis weight approx 60-90 g
Pig elongated bean shape smooth flattened from side to side and thin 10-12 renal papillae with a renal pelvis weight approx 80-180 g
Horse right side - heart shaped left side - bean shaped smooth deep notch at renal pelvis weight approx 400-600g
Spleens
Ox elongated oval shape bluish colour sharp edges (rounded in younger animals) white lymph follicles easily seen on cross section weight approx 1 kg
Sheep triangular shape - rounded corners ('oyster shape') often attached to pluck red/ brown soft and elastic to the touch weight approx 100 g
Pig elongated/ narrow ('dog tongue') triangular in cross section red colour longitudinal ridge with fat-filled omentum attached weight approx 0.25 - 2 kg
Horse flat sickle shape bluish weight approx 1kg
Testicles
Ox/ Bull elongated with oval outline yellow parenchyma heavy veining narrow epididymis - closely attached along posterior border - head is long and curved over the upper extremity and 1/3 the way down the anterior border weight approx 280-340 g
Sheep/ Ram similar to bull - but smaller pear shaped and more rounded than a bull's light veining weight approx 250-280 g
Pig/ Boar very large and irregularly elliptical grey/ brown parenchyma branched main vein distinct lobulations abundant interlobular tissue well developed epididymis - forms blunt conical projection at both ends of testicle
Horse/ Stallion relatively smaller than those of the other animals red/ grey parenchyma ovoid but compressed from side to side light veining body of epididymis loosly attached but the head and tail are more firmly attached to the lower thirds of the upper and lower extremities weight approx 220 g
Skeletons
Ox/ Horse spinal processes of the anterior dorsal vertebrae of horse are shorter and stouter than Ox ribs of Ox are smoother and in the lower 2/3 are broader ox has 13 pairs of ribs - horse has 18 Ox scapular is more triangular than horse and the spine is more prominent and placed further forward (the supraspinus fossa is narrow and doesn't extend to the lower part of the bone). Instead of subsiding as in the horse, the spine rises and has a pointed projection (acromion). There is a distinct notch in the glenoid cavity of the horse, not in the Ox. horse humorus has 3 tuberosities - lateral tuberosity is divided into 2 giving a bicipital groove). In the Ox the lateral tuberosity is very large and rises 2.5-5 cm above the level of the bone the ulna extends only half way down the radius in the horse. In the Ox it is more developed and reaches the carpus the small head of the fibula in the Ox is hook-shaped. In the horse it is separate and extends 2/3 down the tibia
Sheep and Goat bones of the goat are more slender than those of the sheep and the bony processes are longer and more sharply edged than in the sheep the scapula of the sheep is shorter compared to its breadth and the edge of the spine in the centre is thickened backwards, while in the goat it is straight and unthickened
Cat and Rabbit the lateral processes of the lumbar vertebrae in the cat finish in a point whereas in the rabbit there are 2 extensions - one backwards and one forward 13 pairs of rounded ribs in the cat, 12 pairs of more flattened ribs in the rabbit rabbit has long metacromium on the scapula directed backwards which is absent in the cat tibia and fibula in the cat are separate for their complete length. In the rabbit they are separate only in the upper half radius and ulna are separate in the cat but are united in the rabbit the male cat has an os penis the coccygeal vertebrae in the rabbit are very small
Rabbit skeleton ...
Cat skeleton ...
Fowl skeleton ...
Fowl and Rabbit bones of the fowl tend to be whiter in colour and larger in all dimensions than the rabbit the humerus is hollow in the fowl the metatarsus is very large in the fowl and has a spur in the male the ribs are flat with uncinate processes projecting backwards in the fowl. In the rabbit the ribs are long and slender with no uncinate processes in the fowl the pelvis and sternum are very typical and not at all like those in mammals in fowl the clavicle (wish bone) and coracoid are present unlike in the rabbit the fowl scapula is not the typical triangular shape the sternal bones are fused in the fowl but not the rabbit the pygostyle is present in the fowl