Comparative Vertebrae Anatomy of Different Animals

Welcome again. Hope you are well. I recommend reviewing my articles on Comparative Anatomy of Forelimb and Hind Limb Bones if you haven’t already. Today, I will discuss the comparative anatomy of vertebrae (atlas, axis, thoracic, lumbar, and sacrum) in different animals (ox, sheep, goat, horse, and dog).

If you have a basic idea of vertebral osteology and want to memorize these features, please visit my previous article: Animal Vertebrae Identification, which contains more videos and images.

Let’s compare the osteological features of vertebrae from different animals.

I will compare vertebrae based on the most important osteological features; you may discover more to compare.

Vertebrae anatomy of different animal

We will compare the osteological features of the following vertebrae:

• Comparative anatomy of the atlas of the ox, sheep, goat, horse, and dog
• Comparative anatomy of the axis of the ox, sheep, goat, horse, and dog
• Comparative anatomy of other cervical vertebrae of the ox, sheep, goat, horse, and dog
• Comparative anatomy of thoracic vertebrae of ox, sheep, goat, horse, and dog
• Comparative anatomy of the sacrum of the ox, sheep, goat, horse, and dog

Let’s learn and identify the comparative osteological features of vertebrae from different animals.

Comparative anatomy of atlas vertebrae from different animals

Consider the following important osteological features when comparing atlas anatomy among animals:

Wing or transverse process

• Less curved in ox, more curved in sheep and goat, more curved in horse, and flattened, wide horizontally in dog

Ventral arch

• The ventral arch is thick, with a ventral tubercle present in ox, sheep, and goat.
• More thick and the presence of a ventral tubercle in the horse
• The ventral arch is not developed in the dog.

Foramen

• Intervertebral and alar foramina are present in ox, sheep, goat, horse, and dog. The alar notch is present in the case of the dog only.
• The transverse foramen is absent in ox, sheep, and goat.

You may get basic information from the table below –

Features	Ox, sheep and goat	Horse	Dog
Wing	Less curved in ox, Modified and form blunt point caudally in goat	Modified and curved	Flattened and wide horizontally
Ventral arch	Thick and form ventral tubercle	More thick and form ventral tubercle	Not developed
Intravertebral and alar foramen	Present	Present	Present. Alar notch present
Transverse foramen	Absent	Present	Present

Comparative anatomy axis vertebrae from different animals

This overview compares the osteological features of the axis vertebra among different animals. The following key features will be discussed for comparison:

Odontoid process

• Short and wide in ox, sheep, and goat
• Narrow and longest in the horse
• Longer and pointed in a dog.

Spinous process

• Short and projected cranially in ox
• Divided into two parts by a ridge and projected caudally in the horse
• Thin and large in a dog

Intervertebral foramen

• Present in ox, sheep, goat, horse, and absent in dog

Let’s get all important information (in short) from the table below –

Features	Ox, sheep and goat	Horse	Dog
Odontoid process	Short and wide	Narrow and largest	Longer and pointed
Spinous process	Short, projected cranially in ox,  not so longer in goat	Divided into two part by ridge, projected caudally, connect to caudal articular process	Thin and larger
Transverse foramen	Present	Present	Absent

Comparative anatomy of other typical vertebrae (third, fourth, and fifth) from different animals

We will consider the following osteological features to compare the cervical vertebrae from different animals –

Body of vertebrae

• The body of the vertebrae is shorter in ox, sheep, and goat, longer in the horse, and relatively longer and compressed dorso-ventrally in the dog.
• Longer in the case of a horse
• Relatively longer and compressed dorso-ventrally in the dog

Ventral crest or spine

• Prominent in ox, sheep, and goat
• More prominent in horse and
• Not so prominent in the dog

Cranial articular process

• Faced dorso-medially in case of ox, sheep, goat, and also in the horse
• Almost dorsally in the dog

You may also get the important information from the table below –

Features	Ox, sheep and goat	Horse	Dog
Body	Shorter	Longer	Relatively longer and compressed dorso-ventrally
Ventral crest	Prominent	More prominent	Not prominent
Cranial articular process	Dorsomedially	Dorso-medially	Almost dorsally

Comparative anatomy of the sixth cervical vertebra from different animals

To compare the sixth cervical vertebrae across animals, we will focus on these osteological features:

Ventral part of the transverse process

• The ventral part of the transverse process is large, thick, and quadrilateral in shape; it is oriented nearly parallel to the sagittal plane and directed downward in ox, sheep, and goat.
• Divided into three parts, and caudal articular process is short and thick in the horse.
• Divided into two parts in a dog

You may also follow the table below –

Features	Ox, sheep and goat	Horse	Goat
Ventral part of transverse process	Large, thick, ventrally directed	Three parts	Two parts
Spinous process	Rudimentary	Developed	Rudimentary

Comparative anatomy of thoracic vertebrae from different animals

We will consider the following important osteological features to compare the thoracic vertebrae anatomy from different animals –

Body of vertebrae

• Longer and constricted in the middle in ox, sheep, and goat.
• Short and constricted in the middle of the horse
• Wide and compressed dorso-ventrally in the dog

Arch of vertebrae

• Notch is shallow in ox, sheep, and goat.
• The caudal notch on the arch is larger in the horse.
• Notch is shallow in the dog, also.

Spinous (accessory process)

• The last three thoracic vertebrae possess an accessory process (in the spinous process) in ox, sheep, and goat.
• The accessory process is absent in the horse.
• Present in the dog also

Okay, let’s get all the important comparative features from the table below –

Features	Ox, sheep and goat	Horse	Dog
Body	Longer, constricted in middle, relatively wider in goat and less constricted	Short and constricted at middle	Wide and compressed at dorso-ventrally
Arch	Notch shallow	Caudal notch larger	Notch shallow
Spinous process	Thin and sharp	Thick and blunt	Cranial surface convex
Accessory process on spinous process	Present in last three spinous process	Absent	Present

Comparative anatomy of lumbar vertebrae from different animals

We will consider the following important features to compare the lumbar vertebrae from different animals –

Body of vertebrae

• The body is constricted at the middle and expanded at either end, with a rudimentary ventral crest present in ox, sheep, and goat.
• Semi-eliptical body and present a distinct ventral crest in the horse
• The body is flatter from top to bottom in the dog.

Transverse process

• Curved laterally and have expanded ends in ox, sheep and goat
• Elongated plate and flattened dorso-ventrally in the horse
• Thin plate-like and directed cranially and ventrally in the dog

You may also follow the table below –

Features	Ox, sheep and goat	Horse	Dog
Body	Constricted at middle, expanded at both ends, rudimentary ventral crest	Semi-eliptical body, distinct ventral crest	Dorso-ventrally flatten body
Articular process	Facet strongly curved	Dorsal concave surface	Larger and compressed laterally
Transverse process	Curved laterally and have expanded ends	Elongated plate and flattened dorso-ventrally	Thin plate, directed cranially and ventrally

Comparative anatomy of sacrum vertebrae from different animals

We will look at the following main features to compare sacrum vertebrae from different animals –

Fusion of bones

• Five vertebrae are fused to form the sacrum in the ox, horse, and the triangular in shaped.
• Three vertebrae are fused to form the sacrum in the dog, and it is quadrangular in shaped.

Spinous process

• United to form the median sacral crest in ox, sheep, goat, and also in the dog.
• Separated sacral spine and directed dorsally and caudally in the horse

Wing of the sacrum

• Curved ventrally and cranially, a quadrangular short bone in ox, sheep, and goat
• Strong prismatic bone with a pointed end in a horse
• Prismatic in the shaped of a dog

Sacral tuberosity

• Absent in ox, sheep, goat, and dog
• Present in the horse and more prominent

Let’s get all the important features in the table below –

Features	Ox, sheep and goat	Horse	Dog
Fusion of bones	Five in ox; triangular , three in sheep, goat	Five vertebrae	Three
Spinous process	United to form median sacral crest	Separated and bified (except first)	Fused to form medial sacral crest
Wing	Curved, quadrangular	Strong prismatic, pointed	Prismatic
Sacral tuberosity	Absent	Prominent	Absent
Transverse process	Rudiment	Prominent	Rudiment

Conclusion

I hope this overview clarified the comparative anatomy and key osteological features of vertebrae in various animals, such as ox, sheep, and goat, so you can confidently identify different vertebrae based on these features.

If this overview did not address all your questions about vertebral anatomy, please refer to lectures or reference books. For more veterinary comparative anatomy insights, connect with me or follow my articles.

If possible, I may update or add more information, pictures, and videos on this topic in the future. Your input is valuable to me—if you notice any mistakes or have suggestions, please let me know in the comment box. Thank you very much for your support.