The coronary arteries of the dromedary camel (Camelus dromedarius)

Gross anatomy of the heart of the alpaca (Vicugna pacos, Linnaeus 1758)

The available information about anatomical characteristics of the cardiovascular system of the alpaca (Vicugna pacos, Linnaeus 1758) is scarce. The general objective of this work was to describe its heart anatomy. We dissected six adult animals and five neonates. The heart of the alpaca was located in the middle mediastinum, with a craniocaudal extension from the third to the sixth rib. No ligament that connected the fibrous pericardium to the sternum or to the diaphragm was detected. In the right atrium, there was a developed crista terminalis and small pectinate muscles. In the right ventricle, the septomarginal trabecula was very large. From the proximities of the interventricular septum arose small septomarginal trabeculae that ended in carnous trabeculae of the septal wall. The left atrium included little developed pectinate muscles. On the left ventricle, both papillary muscles were bilobed. Two left septomarginal trabeculas were detected in this ventricle. The left subclavian artery was originated from the aortic arch separately from the brachiocephalic trunk, and bicarotid trunk was present. The other branches of the subclavian artery were similar to the domestic ruminants. The arterial supply of the heart was of the right type. In conclusion, the heart anatomy of alpaca and the irrigation of thoracic cavity were more similar to those of old world camels and different from domestic ruminants.

Coronary Artery Anomalies in Animals

Coronary artery anomalies represent a disease spectrum from incidental to life-threatening. Anomalies of coronary artery origin and course are well-recognized in human medicine, but have received limited attention in veterinary medicine. Coronary artery anomalies are best described in the dog, hamster, and cow though reports also exist in the horse and pig. The most well-known anomaly in veterinary medicine is anomalous coronary artery origin with a prepulmonary course in dogs, which limits treatment of pulmonary valve stenosis. A categorization scheme for coronary artery anomalies in animals is suggested, dividing these anomalies into those of major or minor clinical significance. A review of coronary artery development, anatomy, and reported anomalies in domesticated species is provided and four novel canine examples of anomalous coronary artery origin are described: an English bulldog with single left coronary ostium and a retroaortic right coronary artery; an English bulldog with single right coronary ostium and transseptal left coronary artery; an English bulldog with single right coronary ostium and absent left coronary artery with a prepulmonary paraconal interventricular branch and an interarterial circumflex branch; and a mixed-breed dog with tetralogy of Fallot and anomalous origin of all coronary branches from the brachiocephalic trunk. Coronary arterial fistulae are also described including a coronary cameral fistula in a llama cria and an English bulldog with coronary artery aneurysm and anomalous shunting vessels from the right coronary artery to the pulmonary trunk. These examples are provided with the intent to raise awareness and improve understanding of such defects.

Inner ventricular structures and valves of the heart in white rhinoceros (Ceratotherium simum)

In this study, we describe the internal structures of both ventricles and the valvular apparatus of the heart of the white rhino. In the right of the heart, three papillary muscles were found in septal and marginal walls and m. papillaris magnus was the biggest. There was only one m. papillaris parvus in the right ventricle. The right atrioventricular valve was tricuspid, and the parietal cusp was longest. In the left of the heart, two papillary muscles were found on the septal wall and the subauricular was the biggest. The left atrioventricular valve was bicuspid and the parietal cusp was longest. There were no nodules in the valves of the pulmonary trunk and aorta, and the semilunar valves had many fibrous folds and transparent parts. Within the cardiac skeleton there was a cartilago cordis which occupied a small part of the right fibrous trigone. While the right ventricle included only one septomarginal trabecula, there were many trabeculae in the left ventricle. In both ventricles, the endocardium was thin and the subendocardial network was visible, also their continuation with the septomarginal trabeculae. We also found many trabeculae carneae in the dorsal part of the ventricles.

The arterial vascularization of septum interventriculare in donkeys (Equus asinus L.)

In this study, arteries that supply the septum interventriculare in donkeys, their course and variations, if present, were defined. Six hearts belonging to donkeys of varying age and sex constituted the material of the study. In order to expose the arteries, latex coloured with Rotring ink was injected into a. coronaria sinistra and a. coronaria dextra and dissection was performed. The arterial vascularization of the heart in donkeys is supplied by a. coronaria sinistra and a. coronoria dextra, which have their origin at the aorta. A. coronaria sinistra gives off two branches: one is ramus interventricularis paraconalis, which extends into the sulcus interventricularis paraconalis and the other is ramus circumflexus sinister, which lies within the sulcus coronarius. A. coronaria dextra is formed by the union of ramus interventricularis subsinuosus and ramus circumflexus dexter. Septum interventriculare is supplied by rr. septales, which originate from ramus interventricularis paraconalis, a branch of a. coronaria sinistra, as well as rami septales which have their origin in ramus interventricularis subsinuosus, a branch of a. coronaria dextra.

The macroanatomy of coronary arteries in donkeys (Equus asinus L.)

The aim of this study was to define the arteries that supply the cardiac muscle in donkeys with regard to their course and possible variations. Six hearts belonging to donkeys of different age and sex constituted the material of the study. Following exposition of the arteries by means of injection of latex coloured with Rotring ink to a. coronaria sinistra and a. coronaria dextra, dissection was performed. The arterial vascularization of the heart in donkeys was determined to be supplied by a. coronaria sinistra and a. coronaria dextra which originate from the aorta. A. coronaria sinistra, measured to be larger than a. coronaria dextra, was determined to have its origin at the aorta, at the level of the free border of valvula semilunaris sinistra, and to extend between truncus pulmonalis and auricula sinistra. The mentioned artery was detected to give off two branches, namely, ramus interventricularis paraconalis and ramus circumflexus sinister which extend in sulcus interventricularis paraconalis and sulcus coronarius, respectively. However, a. coronaria dextra was determined to have its origin at the beginning of the aorta, at the level of valvula semilunaris dextra, and to extend to margo ventricularis dexter between truncus pulmonalis and auricula dexter. This study has revealed ramus interventricularis subsinuosus and ramus circumflexus dexter to intercommunicate by means of anastomosis and to form a. coronaria dexter. Examination of material revealed the absence of anastomosis between r. circumflexus sinister and r. circumflexus dexter. Branches named rami septales, originating from ramus interventricularis paraconalis and ramus interventricularis subsinuosus were determined to supply septum interventriculare. Ramus proximalis atrii sinistri was determined to have its origin at ramus circumflexus sinister whereas ramus proximalis venriculi dextri was determined to stem from the beginning of a. coronaria dextra in the material of this study. However, examination of the cranial and caudal branches of ramus coni arteriosi, revealed the cranial branch to be ramus proximalis ventriculi dextri in a cadaver.