Very few animals possess visceral bones in different soft organs like the heart, eye, and nose. Here, you will know the answer to the question – what animal has a bone in its heart with labeled figures.
Quick answer: There are many animals, like cattle, buffalo, sheep, goats, deer, and horse have a bone in their heart that supports the cardiac valves.
I will show you the exact location and anatomy of the bone from the cattle’s heart with diagrams.
What animal has a bone in its heart?
The large ruminant, like cattle and buffalo, has a small but identifiable bone in their heart. They are known as the ossa cordis of cattle and buffalo that specifically support aortic, bicuspid, and tricuspid valves.
Again, these bones are also found in the heart of small ruminants like sheep, goats, and deer. But, they are smaller than those of the ossa cordis of large ruminants.
Here, Figure 1 shows the location and shape of the bone from the heart of the cattle.
These types of bones (bones in the soft tissue) are also known as the visceral or splanchnic bones. These bones are not part of the animal /cattle/ cow skeleton and occur in very few organs of the body.
Location of the os cordis (cardiac bone) in the cattle heart
Before going to locate the os cordis, you might have the basic anatomical features of the cattle heart. Here, Figure 2 shows the atrium, ventricles, right and left atrioventricular valves, aorta, and pulmonary trunk from the cattle heart.
It is very important to identify the right and left ventricles / atrium practically. This is because, depending on your identifying skill, you may easily understand the location of the aortic, tricuspid, and bicuspid valves.
Key features to identify the right and left ventricles of the cattle heart –
- The left ventricular wall is thin and doesn’t reach the apex,
The os cordis / bone of the cattle heart is located between the aorta and right and left atrioventricular valves (tricuspid and bicuspid valves). Sometimes this bone may occur singly in the ruminant heart or may be double, right and left os cordis.
Here, Figure 3 shows the exact location of the os cordis among the aorta, tricuspid (right), and bicuspid (left) valves.
If the cattle’s heart presents right and left os cordis, the right one is comparatively larger than that of the left. The right os cordis is located in the cardiac muscle of the cattle’s heart, just proximal to the interventricular septum at the level of conus arteriosus.
Sometimes you may find this bone in the junction between intrartial and inter-ventricular septum. It may also extend cranially into the rings of atrioventricular valves.
Anatomy of the os cordis in the cattle heart
According to Ghonimi et al., this cardiac bone is a fibrous structure that consists of collagen and elastic fibers. This is because they can maintain the shape of the cattle’s heart during systole.
The single or double cardiac bone possesses two trigones – right and left. Each of the right and left trigones is placed into the corresponding atrioventricular ring.
Here, Figure 4 shows the position of the right and left trigones among the aortic, bicuspid, and tricuspid valves.
Trigone can be made of bone, hyaline cartilage, and fibrocartilage. Depending on the components of the trigone, they are classified as the follow –
- Os cordis: When the trigone is made up of only bone, then it is known as the os cordis.
- Cartilago cordis:when the trigone is formed by the distinct cartilage in the heart of cattle or other animals are termed the cartilago cordis.
Again, other authors measured the length of the os cordis about 30 – 40 millimeters. They describe this cattle’s cardiac bone as follows –
- It has two surfaces: the aortic (concave) and the ventricular surface (convex).
- Possess two borders: dorsal and ventral borders, and
- It also possesses two extremities: cranial and caudal,
Why is this bone important in the large ruminant heart?
Different authors like Pour, Ghonimi, and Ergerbacher have investigated the os cordis of the heart. They proposed their theories in relation to the functions of the os cordis in the cattle’s heart.
The os cordis / cardiac bone plays a great role in protecting the damage of cattle’s heart specially in the valve area, during systole. Again, as this cardiac bone is embedded into the cardiac muscles, it indirectly enhances the contraction of the heart.
According to Trainini et al., the os cordis of a cattle heart works as a supportive structure. They usually support the right and left atrioventricular valves during the contraction of the heart.
Conclsuion
So the answer to the question ‘What animal has a bone in its heart’ is that large ruminants like cattle and buffalo have a bone in their heart. But the small ruminants like sheep, deer, and goats also have bones in their heart.
The number of bones in an animal’s heart varies according to species. Again, in a specific species like cattle, you may find a single or double cardiac bone (os cordis) in their heart.
References
- Aoun, H A, and Kadhim, A B. Os cordis in local adult male ruminants: Histomorphological and histochemical study. Iraqi Journal of Veterinary Sciences, Vol. 39, No. 4, 2025 (757-763)
- Egerbacher M, Weber H, Hauer S. Bones in the heart skeleton of the otter (Lutra lutra). J Anat. 2000;196(3):485–91.
- Ghonimi, W, Abuel-atta, AA, Bareedy, MH, Balah A. Left Atrium of the Mature Dromedary Camel Heart (Camelus dromedaries): Microanatomy. Journal of Advanced Veterinary Research, 2014; 4:24-34.
- Pour, A. Comparative morphometry of the heart in Holstein and a native Iranian cow breeds wth emphasis on the OS cordis. Indian Veterinary Journal,2004; 81, 806-809.
- Trainini, J, Lowenstein, J, Beraudo, M, Wernicke, M, Trainini, A, Llabata, VM, Carreras, CF. Myocardial torsion and cardiac fulcrum. Morphologie : bulletin de l’Association des anatomistes, 2021; 105(348), 15–23.
