Abstract
The heart is the chief organ of the cardiovascular system, which distributes oxygenated blood to all parts of the body. This study was conducted to identify differences in the hearts of sheep and goats, both internally and externally. The study was performed on the hearts of healthy sheep and goats, all from a native breed, aged 2 to 4 years. The animal hearts were obtained from the slaughterhouse in Matrouh governorate. Once obtained, the samples were thoroughly cleaned and then dried on clean tissue to prevent debris or blood accumulation, which could compromise image quality. All hearts were subjected to external measurements, then longitudinally and transversely sectioned to explain all differences that can be observed either internally or externally. The shape of the heart was conical in shape with a blunt apex in the case of sheep, while the heart of the goat was conical in shape with a pointed apex, similar to the heart of the sheep, which was compressed dorsoventrally, while the heart of the goat was more elongated. The heart of both animals consists of four chambers: two atria dorsally and two ventricles ventrally, which are separated from each other by the coronary groove. The two ventricles are separated from each other by the right and left interventricular grooves, which connect on the cranial border of the heart. The right interventricular groove was straight in sheep, while in goats it was more sinuous. Both hearts showed a shorter, shallower intermediate groove on the caudal border. Internally, the right and left ventricles contain papillary muscles, which give chordae tendinae attached to the tricuspid or bicuspid valve, respectively. The right ventricle of both hearts contained three papillary muscles, which were larger in sheep than those of the goat. The left ventricle of both hearts contained only two papillary muscles, which were approximately similar in length. Still, those of sheep were wider with longer chordae tendinae than those of the goat. The gross morphometry of the heart serves as a guide for imaging morphometrics that aid in accurate diagnosis.

Key words: Heart, sheep, goat, gross anatomy, morphometry.