Morphological and morphometrical study of fetal heart in sheep

Sheep as an experimental animal has been used in many veterinary researches. Although heart has been consistently considered as one of the most sensitive organs in medical basic science researches, there was not any available report about embryology and macroscopic developmental growth in sheep heart. Therefore, this study was done to investigate morphology and morphometry of sheep heart in fetal period. In present study, 41 sheep fetuses were collected from slaughterhouses and fixed in 10% formalin solution. These fetuses were divided into 3 groups according to their crown – rump – length. First group has CRL≤15 cm, second group has CRL: more than 15 cm and less than 30 cm and the last group has CRL≥30 cm. Fetal CRL were 6 to 40 cm, approximately resulting in ages from 48 days to 120 days. Morphometrical parameters of the fetal heart include: heart weight, long and short diameters of the heart, circumference of the heart, cranial and caudal borders, length of right and left ventricles, thickness of right and left ventricles wall and interventricular septum of the heartwere measured. The results showed that the body weight process and increasing of the mentioned parameters followed by fetus aging. Also, there was not significant difference between both sexes. The chart of their process showed an ascending increase from 99 days onwards and their growth rate was higher from these days. From the morphological standpoint, the fetal heart showed sharp apex and had right and left atriums, right and left ventricles and coronary groove. The study of internal surface of the hearts showed some small tendons in the ventricles. They did not have any links between papillary muscles and valve cusps in the ventricles chambers. They called small moderate bands. The results showed that concomitant with general developmental growth of fetal sheep body like weight and length, also the fetal heart showed increasingly growth in all dimentions.