arrangement of the muscular fibers of the ventricular portion of the heart of the donkey

Twelve adult donkeys' formation hardened ventricles of the hearts were used in this study. The ventricular myocardium is formed of three layers: Subepicardial [outer], middle and subendocardial [inner]. The subepicardial layer of the left ventricle, is more thicker [0.3 cm] than of the right ventricular [0.2 cm]. This layer is decreased gradually in the thickness towards the apex of the heart [left ventricle]. On the auricular surface of the ventricle this layer is directed caudoventrally mostly, but it is directed transversely of the conus arteriosus. On the atrial surface, the subepicardial layer is directed cranioventrally, except at the proximal third of the right ventricle where it has transverse direction. At the apex at the heart, the subepicardial fibers has clockwise manner and is formed a vortex cardis. The middle layer is the thickest layer of the heart [1 cm] specially at the middle part of the left ventricle. The outer part of this layer encircle both ventricles and the inner part encloses to each ventricle. The middle layer is attached at the fibrous skeleton at the atrioventricular ring similar to the subepicardial and subendocardial layers. The subendocardial layer is thicker than the subepicardial layer and has 3 different directions [ventricle, transverse, oblique caudodorsally] in the left ventricle, but in the right ventricle there are 2 directions [ventricle, cranioventrally]

External features of stomach and intestine in some wild birds in relation to food habits with special references to their vasculature

The present study was carried out on the stomach and intestine of four groups of wild birds which were classified according to their food habits into insectivorous, omnivorous, granivorous and herbivorous groups. The anatomical differences of the stomach and intestine were recorded. The average length and weight of each part of the stomach as well as intestine were measured. The arterial supply of gastrointestinal tract with relation to food habits was studied also. The data revealed that the percentage of the length of the gl and ular stomach to that of the trunk increased from herbivorous to insectivorous where it reached its maximum in muk [21%]. The percentage of the length of the muscular stomach to that of the trunk increased from insectivorous to the herbivorous where it was the longest in moorhen [36.4%] hence the muscular stomach was larger and stronger in herbivorous group where their food was of hard tincture and vice versa in the insectivorous which present a soft and easily digestible food. Some correlations between the percentage of the length of the same parts of intestine and type of food, to that of the trunk were done. The two caeca and rectum were generally increased from the insectivorous muk to the herbivorous [moorhen] and vice versa of the duodenum. The percentage of the weight of the gastrointestinal tract to the total weight of the body increased from insectivorous to the herbivorous where it reached its maximum, [14.97%] in moorhen. The proximal, middle and distal parts of the caeca, either not clear in insectivorous and omnivorous or clear in granivorous and herbivorous birds. The gl and ular stomach was supplied by large dorsal and ventral proventricular arteries of celiac artery, the dorsal proventricular artery extended caudally to the dorsal margin of the muscular stomach in insectivorous and omnivorous. While, in granivorous and herbivorous the dorsal aspect of the gl and ular stomach was supplied by short and small, two dorsal arteries [proventricular and gastric]. According to food habits, the arterial supply of the intestine was variable, jejunal, and one ileal arteries to small intestine in insectivorous, 4 jejunal and 2 ileal arteries in the omnivorous, 6 jejunal and 5 ileal arteries in granivorous, while in herbivorous, 8 jejunal and 5 ileal arteries where observed. The cranial and caudal branches of the caudal mesenteric artery are arise either separated in insectivorous or separated with anastomotic branch in omnivorous, and by a common trunk in granivorous and herbivorous