Gross, Histological and Histochemical Studies on the Chordae Tendineae of Heart in Prenatal Goat (Capra hircus)

Abstract

A study was conducted on goat fetuses collected from local slaughter houses to know structure of chordae tendineae during prenatal life. The fetuses were divided into three groups viz; Group-I (early prenatal period; d†50 days of gestation), Group-II (mid prenatal period; e†51 days and d†100 days of gestation) and Group-III (late prenatal period; e†101 days) comprising of 12 goat (each). The heart tissues were collected and fixed in Neutral buffered formalin for routine histology, PAS and AMPS, Zenker’s solution for DNA and cold acetone for lipid, alkaline phosphatase and acid phosphatase studies. The study revealed that chordae tendineae were thick, short and less branched in early stages of gestation. Size and number of chordae tendineae increased with increase in gestation period. There was no set pattern of their attachment with the cusps, however, chordae tendineae arising from one papillary muscle were attached with two cusps and each cusp was attached with the chordae tendineae coming from two papillary muscles. Histologically, on 32 days old goat embryo chordae tendineae were noticed in the ventricle and its central core was made up of myocardial cells with reticular fibers surrounded by single layer of endothelial cells. In mid and late prenatal periods the chordae tendineae were mainly collagenous along with few fibroblast, reticular and elastic fibers, and lined by endothelial cells. The histochemical reaction showed that the activity for the presence of polysaccharides, lipids, DNA and alkaline phosphatase in the chordae tendineae increased with the advancement of age.