The cow lumbar vertebrae form the lower back region of the spine. You may easily identify these vertebrae from the cow’s spine with their unique osteological features.
Here, I will show you the unique osteological features of these lumbar vertebrae from the cow’s axial skeleton. You will easily understand the osteological differences between the lumbar vertebrae while comparing them with other vertebrae.
Quick overview: the cow lumbar vertebrae are in the lower back region and possess long plate-like transverse processes. You may easily distinguish the first lumbar vertebra from the last thoracic vertebra by their lack of costal facets.
Finally, I will show the anatomical differences between the horse and cow’s lumbar vertebra with the diagrams. So, let’s continue this article to learn the details (number and structure) of bovine lumbar vertebrae.
Cow lumbar vertebrae
The cow lumbar vertebrae also possess the bodies, arches, and processes like a typical vertebra. But, you will find the larger and long transverse processes in the structure of a lumbar vertebra.
First, let’s identify the different osteological features of the cow lumbar vertebra –
- Short and flattened body of the lumbar vertebra,
- Cranial less convex and caudal less concave extremity of the lumbar vertebra,
- Equal-sized arches (pedicles and laminae),
- Larger caudal notches on the pedicle of the lumbar vertebra,
- Cranial concave (dorsally) articular process,
- Caudal convex (ventrally) articular process of lumbar vertebra,
- Longer, flattened (plate-like) transverse process of the lumbar vertebra, and
- The quadrilateral dorsally directed spinous process of the lumbar vertebra,
The labeled diagram identifies all these features from the bovine lumbar vertebrae. The bodies of these lumbar vertebrae are wider and flattened compared to the other vertebrae of the spine.
If you want to memorize the typical features of a vertebra, you may go through the below-mentioned article from anatomy learner –
The cranial convex body of the first lumbar vertebra articulates with the caudal end of the last thoracic vertebra. Again, the last lumbar vertebra articulates with the body of the sacrum bone.
The features of the cow sacrum vertebrae are different than the lumbar vertebra. You may get an idea of the different features of sacrum bone from the below-mentioned article –
Unique features of cow lumbar vertebra
Now, you will know the unique osteological features of the cow lumbar vertebra. Here, I will enlist the unique features of the lumbar bone, but you may learn more in the next section.
- #1. The body of the cow lumbar vertebra is compressed dorsoventrally (looks like semi-elliptical),
- #2. There are no costal facets and ventral crest in the structure of lumbar vertebrae,
- #3. The body of the last lumbar vertebra is a little more compressed than the other vertebrae of this series,
- #4. The pedicle and lamina of the lumbar vertebra are equal in size and possess notches on both ends,
- #5. You will see the larger notches on the caudal aspect of the pedicle of a lumbar vertebra that forms the larger intervertebral foramen,
- #6. The neural rings of the lumbar vertebrae (first to fourth) are round and gradually become triangular in the last,
- #7. The junction between the body and pedicle of the lumbar vertebra possesses a long, plate-like transverse process that inclines cranially,
- #8. You will find the cranial curved inward articular process and caudal convex and pointed articular process in the lumbar vertebra,
- #9. The spinous process is in the form of quadrilateral plates and is of uniform height,
Sometimes you may find the accessory process or bifid structure in the spinous process of a lumbar vertebra. Again, you will find a gradual change in the structure of the transverse process of the ox lumbar vertebra.
How many lumbar vertebrae do cows have?
Quick answer: the cows have 6 (six) lumbar vertebrae that form the bony roof of the abdomen. All these lumbar vertebrae show the typical features of a larger plate-like transverse process and quadrilateral dorsally directed spinous process.
- Number of lumbar vertebrae in cows – 6 (six),
The length of the transverse process of the first lumbar vertebra of an ox is short. Again, you will find the comparatively narrow transverse process in the structure of the last lumbar vertebra of a cow.
The length of the transverse process from the second lumbar vertebra gradually increases and continues up to the fourth vertebral bone. From the fifth lumbar vertebra, the transverse process becomes shorter and narrower.
How many lumbar vertebrae are there in animals?
Quick answer: you will find a variation in the number of lumbar vertebrae (6 – 7) in various animals. In horses, you will find 7 lumbar vertebrae, like the cows.
But the spine of a dog possesses 7 (seven) lumbar vertebrae. In comparison, the pig and rabbit possess 6 – 7 lumbar vertebrae in their spine.
Let’s see the number of lumbar vertebrae in the spine of various animals from Table 1 –
| Animals | Number of lumbar vertebrae |
| Cow / ox | 6 |
| Horse | 6 (5 in few breed) |
| Sheep | 6 or 7 |
| Dog | 7 |
| Pig | 6 – 7 |
| Rabbit | 6 – 7 |
Cow lumbar vertebrae anatomy
In the cow lumbar vertebrae anatomy, I will discuss the details features of the body, arches, and processes with the diagram. So, let’s see and identify the body, arche, and process from the lumbar vertebrae and discuss again –
- Anatomical facts of bodies of the lumbar vertebra,
- Osteological features of the arches of the lumbar vertebra, and
- Osteological features of the three main processes from the lumbar vertebra of cows,
First, let’s start with the features of the bodies of the ox lumbar vertebra.
Body of the bovine lumbar vertebrae
The appearance of the body of lumbar vertebrae in the cow’s spine is somewhat little different in the first three bones. You will see the semi-elliptical body (on cross-section) in the first three lumbar vertebrae.
These first three lumbar vertebrae possess distinct ventral crests. But you will see wider and flatter bodies in the fourth to sixth lumbar vertebrae.
There is no ventral crest in the ventral part of the bodies of the fourth, fifth, and sixth lumbar vertebrae.
Both cranial and caudal extremities are present in the structure of all lumbar vertebrae. But, the cranial extremity of the lumbar vertebra is less convex, and the caudal extremity is also less concave than the cervical vertebrae.
You may see the convexity and concavity of the seventh cervical vertebra from the below-mentioned article of anatomy learner –
You will not find any other essential features in the body of the lumbar vertebra like the bodies of thoracic vertebrae. The dorsal part of the bodies of lumbar vertebrae contributes to forming the base of a rounded or triangular vertebral ring.
Arches of cattle lumbar vertebrae
The arches (both pedicle and lamina) of the lumbar vertebrae are equal in size to the last three thoracic vertebrae. Again, they become gradually smaller from the fourth to sixth lumbar vertebrae.
You will find both cranial and caudal notches in the pedicles on both sides of the lumbar vertebra. But the caudal notches on the lumbar vertebral pedicles are larger compared to the cranial notches.
These larger caudal notches of the pedicle contribute to forming the larger rounded intervertebral foramen. But, you will not find any other intravertebral foramen in the lumbar vertebra like the thoracic vertebra.
You know, the ventral part of an arch (pedicle) arises from the base of the body. Again, the upper plate-like structure above the pedicle is the lamina that forms the roof of the vertebral rings.
Process of ox lumbar vertebra
The structure of the ox lumbar vertebrae shows three developed processes –
- Dorsally – quadrilateral plate-like supraspinous process,
- Cranially and caudally – cranial and caudal articular processes, and
- Laterally – the longer and plate-like transverse processes,
The cranial articular process of the lumbar vertebra is well-developed and possesses dorsal concave surfaces. This dorsal concave surface of the lumbar vertebral articular process receives the caudal articular process of other bones.
Sometimes you may find the mammillary process in the structure of lumbar vertebrae that fuse with the cranial articular process.
The caudal articular surface of the bovine lumbar vertebrae is also well-developed. They possess a ventrally convex articular surface.
This ventral convex articular surface fits into the concave surface of the cranial articular process of the next lumbar bone.
Unique features of a transverse and spinous process
The unique features are found in the structure of the transverse and spinous processes of the lumbar vertebrae. Here, the transverse process of the lumbar vertebrae is elongated and flattened dorsoventrally.
You will find the cranial inclination of the transverse process of the ox lumbar vertebrae. But sometimes, you may find a little variation in the inclination of the transverse process in different breeds of cows.
Again, the inclination of the transverse process of dog and horse’s lumbar vertebrae varies from the cows.
The spinous process of the first two lumbar vertebrae resembles the last thoracic vertebrae. You will find the same length and height of the spinous processes from the third to sixth lumbar vertebrae.
But, the wideness of the spinous processes may diminish in the last two or one lumbar vertebrae. All the spinous processes of the lumbar vertebrae look like more or less quadrilateral plates.
Summary of bovine lumbar vertebra
Now, let’s see the summary of the bovine lumbar vertebra from Table 2. Here, you will only find the unique and short features of the bovine lumbar vertebra.
| Cow lumbar vertebra | Unique features |
| Body | First three – Semi-elliptical and have a ventral crest Last three vertebrae – Wider and flatter Diminish ventral crests |
| Arches | Equal in size in the first three Caudal notch larger Form larger intervertebral foramen |
| Processes | Spinous process – Quadrilateral plate Dorsally directed Articular process – Cranial – dorsally and concave Caudal – ventrally and pointed Transverse process – Long and plate-like structure |
Cow lumbar vertebrae diagram
Now, I will show you all the osteological features again from the cow’s lumbar vertebrae labeled diagram. You will also see how the bodies, arches, and processes articulate and form the joints.
The diagram identifies all the arches, bodies, and processes from the ox lumbar vertebrae (lower back region). Again, the larger foramina from the lumbar vertebrae are also identified in the labeled diagram.
You may find more labeled diagrams on the horse, pig, and rabbit’s lumbar vertebrae on social media of anatomy learners.
What are the differences between the lumbar vertebrae of horses and cows?
Quick answer: the lumbar vertebrae of a horse show a semi-elliptical body with a distinct ventral crest. But there is no distinct ventral crest in the body of the cow’s lumbar vertebra.
Again, the articular process of the horse lumbar possesses a dorsal concave surface with less curve. In contrast, you will find the strongly curved facets on the cranial articular process of the cow’s lumbar vertebra.
You may also see the other osteological differences between the horse and cows’ lumbar vertebral bones from Table 3 –
| Features | Horse lumbar vertebra | Cow lumbar vertebra |
| Number | 6 (six); sometimes five (5) | 6 (six) |
| Body | Semielliptical Present distinct ventral crest | Wider and flatter Rudimentary ventral crest |
| Articular process | Less curve | Have strongly curve |
| Transverse process | Elongated plate Flattened dorsovenetrally | Curved laterally Have expanded ends |
Conclusion
So the cow lumbar vertebrae have an exceptionally larger plate-like lateral transverse process. Again, the quadrilateral plate-like dorsally directed spinous process is another important osteological feature of a lumbar vertebra.
The appearance of bodies and curved articular cranial articular processes might help you to differentiate the cow lumbar vertebrae from others. You may also differentiate the bovine lumbar vertebrae from other species like horses, dogs, and pigs.
