The pet owner and the first-year veterinary students have a common inquiry – how many bones does a dog have? Ideally, you will find 321 bones in the skeleton of a dog. But, this number of bones may vary from 291 to 321 in the different breeds of the dogs.
Here, I will show you the number of bones from the different regions like the forelimb, hindlimb, spine, skull, ear, and tail of a dog. You will know why and how dogs have 321 bones in their skeleton.
I hope you will enjoy counting the number of bones from different regions of the dog skeleton. So, let’s continue and know the possible explanation for having 321 bones in a dog.
How many bones does a dog have
Bones are the hardest structures of the animal skeleton and are classified into mainly long, short, flat, irregular, and sesamoid. I have previously described all types of bone from animal skeletons in another article by anatomy learner.
Quick answer: In a dog skeleton, you will find long, short, flat, irregular, and sesamoid types of bone. First, let’s see how many bones does a dog have in its skeletal system –
- Bones in the vertebral column – 50
- Skull and hyoid bones – 50
- Number of ribs and sternum – 34
- Bones in the thoracic limb – 90
- Number of bones in the pelvic limb – 96
- Heterotopic skeleton (baculum) – 1
So, there is a total of 321 bones in the skeletal system. Now, I will show you how there are 50 bones in the vertebral column, 50 in the skull and hyoid apparatus, 34 in the ribs and sternum, 90 bones in the thoracic limb, and 96 bones in the pelvic limb.
But, the number of bones (321) may vary in different breeds of dogs, especially in their vertebrae, skull, and limbs.
Before counting the dog bones, let’s try to identify different types of bones from the different regions. Here, I will help you identify the bones from both axial and appendicular skeletons of the dog. But, you may identify the bones from the dog skeletal system with their details description with the help of another article that was published previously in anatomy learner.
Bones of the axial and appendicular skeleton of a dog with a labeled diagram
Bones identification from dog skeleton
So, this is your first duty to identify different bones from the axial and appendicular skeleton. Let’s try to identify the axial and appendicular bones from the skeletal system with the help of the following labeled diagram.
- Bones of the dog’s axial skeleton – include the bones of vertebrae, skull, ribs, and sternum.
- The bones of the dog’s appendicular skeleton – include the bones of the thoracic limb and pelvic limb.
I think the dog skeleton labeled diagram might help you accurately identify all the bones (291 – 321).
Bones of the vertebral column of a dog
There are approximately 50 irregular bones in the vertebral column of a dog. Like the other animals’ vertebrae, you will also find five groups of bones in the vertebral column of a dog. Let’s see these groups of bones from the vertebral column with their numbers –
- Cervical vertebrae of the dog – 7,
- Thoracic vertebrae of dog vertebral column – 13,
- Lumbar vertebrae of the dog – 7,
- Scaral or sacrum of the dog – 3,
- Caudal vertebrae of the vertebral dog column – 19 – 20.
All these groups of bone from the vertebral dog column are identified in the labeled diagram. First, you should identify the groups of bone-like cervical, thoracic, lumbar, sacrum, and caudal.
A typical vertebra of any animal comprises three parts – a body, arch, and processes. The body is a cylindrical structure that possesses mainly cranial and caudal articular surfaces. But, you may find some other extra features or modifications in the body in different groups of the vertebra.
Again, the arch of an animal vertebra consists of a ventral pedicle and dorsal lamina. These pedicles and lamina of the vertebra help to form the vertebral ring. And they also contribute to forming different processes.
You will find three developed vertebral processes: articular, transverse, and spinous. These processes are very modified in the different groups of the vertebra.
You may learn more about the typical vertebrae and identifying features of another different group of vertebras of an animal from other articles from anatomy learners.
Osteological features of a typical vertebra of animal, and
Identifying features of vertebrae from the animals’ vertebral column.
I hope these two articles will help you identify the different bone groups from the dog’s vertebral column.
Dog skull bones identification
You will find a great variation in the number of skull bones in the different species of dogs. The dog skull bones vary from 36 to 50 bones (including the hyoid and mandible). There are two types of bone present in the skull of a dog – cranium and facial bones.
The cranium bones of the dog skull surround the brain, whereas the fascial bones surround the eye, respiratory, and digestive passageways. You will find 14 bones in the cranium of the dog’s skull. Again, there are 36 bones present in the facial part of the dog skull.
But, first, I would like to show you the different bones from the cranium and facial parts of a dog skull with a labeled diagram. Okay, let’s see the cranium bones from the dog skull –
- Occipital, supraoccipita, and basioccipital bones of dog skull,
- Parietal and interparietal bones of dog skull,
- A frontal bone of dog skull,
- The sphenoid bone of dog skull (presphenoid and basisphenoid),
- A temporal bone of a dog skull, and
- The ethmoid bone of a dog skull.
So, these are the cranial bone that you will get in a dog’s skull. Again, there are almost 36 bones in the facial part of the dog skull. Before counting the number of the facial bones of the skull, first, try to identify them –
- Incisive bones of dog skull,
- The nasal bone of a dog skull,
- Maxilla bone of dog skull,
- Zygomatic and palatine bones of dog skull,
- Lacrimal, pterygoid, and vomer bones of a dog skull,
- Dorsal and ventral concha of the dog skull, and
- Mandible of the dog.
The hyoid apparatus consists of stylohyoid, thyrohyoid, basihyoid, ceratohyoid, and epiphysis. Again, in the middle ear of a dog, you will find malleus, incus, and stapes.
Dog thoracic limb bones identification
How many bones does a dog have in its thoracic limb? Each thoracic limb of a dog contains almost 45 bones. So, you will find 90 bones in two thoracic limbs of a dog. Like other animals, you will find the same bones in a dog’s thoracic limb.
So, first, let’s identify all the bones from the thoracic limb of a dog with the help of a labeled diagram –
- Bones of the shoulder girdles (consists of scapula, clavicle, and coracoid),
- The humerus of a dog (arm or brachium bone),
- Radius and ulna bones (forearm or antebrachium bone),
- Bones of the manus – include carpal, metacarpal, and phalanges,
- Proximal sesamoid bones of the thoracic limb, and
- Distal sesamoid bones of the dog’s thoracic limb.
You will find some differences in the osteological features in the dog’s thoracic limb bones compared to the ruminant. Again, there is a variation in the number of bones found in the dog’s carpal, metacarpals, phalanges, and sesamoid bones.
You may learn the details anatomical facts of the specific bones from the dog thoracic limb from another article by an anatomy learner. All the osteological features of each bone from the thoracic limb are identified with the labeled diagrams.
Read dog skeleton anatomy or dog leg bones anatomy with a labeled diagram.
Identification of bones from dog’s pelvic limb
There are 46 bones in the pelvic limb of a dog skeleton. So, you will find 96 bones in the hind limb of a dog. But, the number of bones (321) may vary in different breeds of the dogs.
Each of the pelvic limbs of a dog consists of a pelvic girdle, thigh, leg, and pes. You will find ilium, ischium, and pubis bone in the structure of a dog’s pelvic girdle. Again, you will find the sacrum bone in the structure of the pelvic girdle of a dog.
Let’s identify the bones from the dog’s pelvic limb –
- Os coxae bones (consists of ilium, ischium, and pubis),
- Femur bone of a dog (bone of the thigh),
- Tibial and fibula bone of dog’s pelvic limb (leg bones),
- Patella of the stifle joint (large sesamoid bone),
- Bones of the hind’s paw – include tarsal, metatarsal, and phalanges,
- Proximal and distal sesamoid bones of the pelvic limb of a dog.
The osteological features of the dog’s hip bone (os coxae), tibia, fibula, tarsal, and metatarsals are somewhat different than those of the ruminants. You will get the details guide on the pelvic limb bones of a dog in another article by anatomy learner.
Suggested reading for you: osteological features of hind limb bones of a dog with a labeled diagram
Dog bone anatomy
It is also important to know dog bone anatomy when you learn how many bones a dog has. You may skip this part (bone anatomy) if you have already read my previously suggested articles from anatomy learner. Here, I will summarize the dog bone anatomy with the labeled diagram.
So, what will I cover here –
- Dog skull bones anatomy,
- Anatomy of the vertebral dog column,
- Dog thoracic limb bones anatomy, and
- Anatomy of the pelvic limb bones of a dog.
Nice, let’s see the anatomical features of the dog bones.
Dog skull bones anatomy
You already know cranial and facial group bones present in the dog skull. They may be paired or unpaired bones in the skull of a dog. Here, I will only show you some of the important anatomical features of the dog skull bones with a labeled diagram.
The dog’s skull is oval elongated but varies highly from breed to breed. You will find a highly curved zygomatic process in the dog skull. The basioccipital bone joins with the tympanic bulla. Again, the interparietal bone fuses with the occipital bone before birth.
The parietal bones take part in the formation of the roof of the cranial cavity. You will find the well-developed alveolar socket for the incisor in the premaxilla bone of the dog. There is no horn in the skull of a dog like a ruminant.
For details description, you may read – dog skull bone anatomy with a labeled diagram.
There is an incomplete orbital rim present in a dog’s skull, which is one of the most exceptional features. The two halves of the mandible of the dog fuse incompletely. Each half of the mandible have three alveolus for incisiors, one alveolus for canine, and seven alveoli for premolar and molar teeth.
You will find another important special feature in the mandible of a dog. There is a depression on the lateral aspect of the ramus of the mandible, which is known as the masseteric fossa.
There are 50 bones in the dog skull, including the hyoid apparatus and mandible.
Anatomy of dog’s vertebral column
In the vertebral column of a dog, you will find cervical, thoracic, lumbar, sacral, and caudal vertebrae. They are 50 bones in a dog’s vertebral column, which may also vary in the different breeds. Here, I will show you a few anatomical features from the dog’s vertebral column bones.
There is a transverse foramen (foramen transversarium) at the caudal aspect of the dog atlas bone. But, you will not find the transverse foramen in the atlas of other animals like a ruminant.
Read – osteological features of atlas or other vertebrae from ruminant with a labeled diagram.
The spinous process of the dog’s vertebrae bones is comparatively short. But, they are broad ventrally and narrow dorsally in the lumbar region of a dog’s vertebral column.
The odontoid process of the dog’s axis vertebra is a pointed and well-developed rod than that of the ruminant. You will find three sacral bones in the structure of a dog sacrum; thus, the sacrum is very short in a dog.
Again, the caudal vertebrae of a dog’s vertebral column are more well-developed than a ruminant. Let’s talk about the sternum and ribs of a dog skeletal system.
The sternum of a dog is formed by eight sternal segments that generally do not fuse. But, they may fuse in the older dog. You will find the longest segment in the manubrium, whereas the last segment is short and possess a narrow blunt end.
There are 13 pairs of ribs found in the axial skeleton of a dog. Nine pairs are sternal, and the other four pairs are asternal ribs. A dog’s ribs are more cylindrical and curved than those of the ruminant’s ribs.
Thoracic limb bones anatomy of a dog
The dog’s thoracic limb bones possess some extra or exceptional osteological features compared to the ruminant. Let’s talk about the exceptional features of the thoracic limb bones of a dog.
The spine of the dog scapula remains in the midline and divides the lateral surface into two halves. Both the cranial and caudal borders of the scapula are convex. You will not find any coracoid process in the dog scapula, and the tuber scapulae are blunt.
There is an acromion process in the dog scapula that is very short and extends to the level of the glenoid cavity. The humerus of a dog is a comparatively more long bone and less twisted than the cow. So, the musculospiral groove is not so prominent in dog humerus. You will find exceptional features – supratrochlear foramen at the distal part of a dog’s humerus.
There are radius and ulna bones separated from each other and in contact at their ends. So, you will find the interosseous space that extends throughout the length of the bones. There are a pair of small tubercles on the olecranon process of the dog’s ulna bone.
You will find three proximal carpal bones and four distal carpal bones in the thoracic limb of a dog. Learn more about these thoracic limbs bones from another article by an anatomy learner.
Dog leg bones anatomy with a labeled diagram.
There are five metacarpal bones in the dog’s thoracic limb. The first metacarpal is short; the third and fourth are the largest, and the second and fifth are almost equal in length. There is two depression for sesamoid bone at the palmar aspect of each metacarpal except the first one.
Anatomy of pelvic limb bones from a dog
There is many variations in the structure of a dog’s hip bone. The ilium of the left and right sides of the dog’s hip is almost parallel. You will see a concave gluteal surface in the ilium bone where the gluteal line is indistinct.
The crest of the ilium bone of the dog hip is strongly convex. You will find a twisted ischium in the hip of a dog. There is also a huge variation in the ischial tuberosity of the dog hip. The dog hip’s ischial tuberosity (tuber ischia) is flat, whereas the trifid is ruminant.
Again, the greater and lesser ischiatic notches are shallow, but the acetabular notch is wide. The femur of a dog also possesses some exceptional osteological features. There is no supracondyloid fossa in the distal part of the dog femur bone. The greater trochanter (laterally) is lower than the humeral head.
Again, the patella of a dog is comparatively longer and possesses a convex anterior surface. The body of the dog tibia is convex medially at the upper end and again convex laterally at the distal end. You will find a prominent tibial crest in the dog’s tibia bone.
The fibula is a long (modified) and thin bone in the dog’s pelvic limb that extends the whole length of the tibia. There is a typical flat end that articulates with the lateral condyle of the tibia.
There are seven tarsal bones found in the pelvic limb of a dog that is arranged in three rows. Again, the dog’s pelvic limb possesses five metatarsal bones. In addition, the number of proximal and distal sesamoid bones is the same as that found in the thoracic limb.
How many bones does a dog have in its body?
Now, let’s count the number of bones from the dog skeleton and get your answer – how many bones does a dog have in its body. I will explain how there are 321 bones in the dog’s skeleton. You will find 134 bones in the axial skeleton, 186 bones in the appendicular skeleton, and one bone-in heterotopic skeleton of a dog.
- The axial skeleton of a dog – consists of a vertebral column, skull, hyoid apparatus, ribs, and sternum (134),
- The appendicular skeleton of a dog – consists of bone from thoracic and pelvic limbs (186), and
- A heterotopic skeleton of a dog – only one bone
Let’s see the name and number of bones in the axial and appendicular skeleton of a dog. Now, I will show you the number of bones from the vertebral column (spine), skull, ribs, sternum, thoracic limb, and pelvic limb of a dog.
How many bones does a dog have in its spine?
You will find 50 bones in a dog’s spine (vertebral column). Let’s see the formula of the vertebral column of a dog. Here, the cervical group of vertebrae comprises 7 bones, the thoracic group contains 13 bones, and the lumbar group consists of 7 bones.
Again, you will find three sacral bones in the sacrum vertebra of a dog. But, the number of caudal vertebrae in dogs varies from breed to breed. Ideally, you will find 20 bones in the caudal group of vertebrae of a dog.
So, there are 50 (7+13+7+3+20) bones in the vertebral column or spine of a dog.
You may learn the anatomical facts of the dog spine from another article by anatomy learner –
Dog spine anatomy with a labeled diagram – bone, muscle, ligament, vessels, and nerves.
How many bones in the dog’s skull
In the skull of a dog, you will find 50 bones (including hyoid and middle ear bones). Now, I will show you how there are 50 bones in a dog’s skull. Let’s see the name and number of dog skull bones from the table or image below.
There are both paired and unpaired bones in the cranium part of the dog skull. You will find the following paired bones in the cranium part of the dog skull –
Occipital, parietal, frontal, and temporal bones of the dog skull
So, in the cranium part of the dog skull, you will find four paired bones (4×2). Again, there are some unpaired bones in the cranium part of a dog skull, and they are –
- Supraoccipital and basioccipital bones (2),
- Interparietal bone in the cranium part of the dog skull (1),
- Basisphenoid and presphenoid bones in the cranium part (2), and
- Ethmoid bone (1)
So, there are six unpaired bones in the cranium part of a dog skull.
Thus, you will find 14 cranium bones in the dog skull.
In the facial part of a dog skull, you will also find both the paired and unpaired bones. You will only find one unpaired (vomer) bone in the facial part of a dog skull. But, there are ten paired bones in the facial part of a dog skull.
The paired facial bones of a dog skull include –
- Incisive bones (2),
- Nasal bones (2),
- Maxilla bone (2),
- Zygomatic bones (2),
- Palatine bones (2),
- Lacrimal bones (2),
- Pterygoid bones (2),
- Dorsal concha (2),
- Ventral concha (2), and
- Mandible bones (2).
So, there are 21 (paired 20×2= 20, and 1 unpaired) bones found in the facial part of a dog skull.
How many bones does a dog have in its middle ear and hyoid apparatus
There are also paired and unpaired bones found in the hyoid apparatus of a dog. The paired bones of a hyoid apparatus of a dog include the following bones –
- Stylohyoid bones (2),
- Thyrohyoid bones (2),
- Creatohyoid bones (2), and
- Epiphyoid bones (2).
Again, there is only 1 unpaired hyoid bone (basihyoid) present in the hyoid apparatus. So, there is a total of 9 bones (2+2+2+2+1) in the hyoid apparatus of a dog.
You will find three bones (Malleus, incus, and stapes) in each dog’s middle ear. So, there are 6 (3×2) middle ear bones in a dog.
Thus, you will find 50 bones in the skull (35), hyoid apparatus (9), and middle ear (6) of a dog.
Number of bones in ribs and sternum of a dog
Okay, how many bones does a dog have in its ribs and sternum? You will find 13 pairs of ribs in the axial skeleton of a dog. So, there are 26 ribs bones in the axial skeleton of a dog.
Let’s count the ribs from the thoracic cage of a dog. You may learn details anatomical facts about the dog rib cage anatomy from another article by anatomy learner.
Please read – dog rib cage anatomy with a labeled diagram.
You will find a dorsoventrally compressed sternum in the axial skeleton of a dog (ventrally). Eight segments are present in the dog sternum, whereas seven are ruminant.
You know the name of the first segment of dog sternum is manubrium, which is longer than other segments. The last segment of the dog sternum is the xiphoid process. You will find a thin cartilaginous plate at the caudal part of the xiphoid process. This is the xiphoid cartilage of the xiphoid process of the dog sternum.
As there are eight segments in the dog sternum, there are eight (8) bones in the dog sternum.
Thus, you will find 34 (thirty-four) bones in the ribs and sternum of a dog.
Bones counting from dog’s thoracic limb
Now, I will show you how there are 45 bones in each thoracic limb of a dog. I know you know all the names of the bones from the thoracic limb of a dog skeleton. Let’s count the bones from the thoracic limb –
- Scapula of a dog in one thoracic limb – 1,
- Humerus bone in dog thoracic limb – 1,
- Radius and ulna bones in the thoracic limb – 2,
- Carpal bones in the thoracic limb – 7,
- Small sesamoid bone in the carpal joint – 1,
- Metacarpal bones in the thoracic limb – 5,
- Proximal sesamoid bones in thoracic limb – 14,
- Phalanges in five digits – 14.
Thus, each thoracic limb of a dog contains 45 bones. Let’s explain how seven carpals and 14 sesamoid and phalanges are present in the dog’s thoracic limb.
In the first row of carpal bone, you will find fused radial and intermediate carpal, ulnar carpal, and accessory carpal. Again, in the distal row of the carpal, you will find four carpal bones – first, second, third, and fourth. So, there are seven carpal bones in the thoracic limb of a dog.
In the proximal sesamoid bone, you will find two types – nine posterior and five anterior. There are two posterior proximal sesamoid bones for each developed digit and one for the first digits. Thus, you will get 9 proximal (posterior) sesamoid bones in the thoracic limb of a dog.
You will find 5 proximal (anterior – one for each digit) sesamoid bones at the anterior aspect. But, the distal sesamoid bones are cartilaginous.
The first digit of a dog contains two phalanges, and the other four digits contain three phalanges. Thus, there are 14 phalanges in the thoracic limb’s digits.
How many bones does a dog have in its pelvic limb?
In this part, I will show you how there are 48 bones in each pelvic limb of a dog. The number of bones in the pelvic limb differs from the thoracic limb. Okay, let’s count the number of bones from the dog’s pelvic limb.
You know os coxae consists of ilium, ischium, and pubis of two lateral sides. So, there are 6 bones in a dog’s hip region (os coxae).
- Os coxae of a dog – 6 bones,
- Femur bone of a dog – 1,
- Patella (ideal sesamoid bone) – 1,
- Tibia and fibula of a dog – 2,
- Tarsal bones of a dog – 7,
- Metatarsal bones of a dog – 5 (4 developed and one considered as the dewclaw),
- Proximal sesamoid bones (anterior and posterior) – 14 (9+5; same as a thoracic limb),
- Phalanges in the dog’s pelvic limb – 12
Thus, there are 48 bones in each pelvic limb of a dog. But, how there are 7 tarsal bones and 12 phalanges in the pelvic limb of a dog.
In the proximal row of dog’s carpus, you will find the tibial and fibular tarsal bones. Again, there is only one carpal bone (central carpal). There are four carpal bones in the distal row of the dog’s carpus – first, second, third, and fourth.
In addition, there are four developed digits in the pelvic limb of a dog, and each of these digits contains three phalanges. Thus, you will find 12 phalanges in the pelvic limb of a dog.
How many bones does a dog have in its tail?
Okay, how many bones does a dog have in its tail? You will find a great variation in the number of tail bones (caudal vertebrae) in a different breeds of the dogs. The average number of the tail bone is 20, but you may find 6 – 24 bones in the tail in the different dog breeds.
The first one or two caudal vertebrae of a dog possess the body, arch, and processes. But, the rest of the caudal vertebrae possess a cylindrical body and modified cranial and caudal articular processes.
Frequently asked questions on dog bones and others
Let’s talk about the number of bones in the different dog breeds and other animals. But, it will be better if you read the previous information to count the number of dog bones.
How many bones can a dog have?
The dog should have a minimum of 291 bones in its skeleton. But, the ideal number of bones is 321 in a dog. I have already described how there are 321 bones in the skeleton of a dog.
How many bones does a fish have?
The fish have approximately 130 (one hundred and thirty) bones in their skeleton. You may read more about the fish bones from another article by anatomy learner.
How many bones does a cat have?
The number of bones in the cat skeleton may vary from breed to breed. Ideally, you may find 230 bones in the skeleton of a cat. You will get more information on the number of cat bones in another article by anatomy learner.
How many bones does a giraffe have?
You will find almost 170 – 175 bones in the skeleton of a giraffe.
How many bones does a bird have?
There is a variation in the number of bones in the bird skeleton. Ideally, you may find 169 bones in the skeleton of a bird.
Why do dogs have more bones than humans
How many bones does a boxer dog have?
The boxer dog also has the same number of bones in its skeleton. That means you will find 319 – 321 bones in the skeleton of a boxer dog.
Conclusion
I hope you got your answer to your question – how many bones does a dog have. So, there are ideally 321 bones in the skeleton of a dog where the vertebrae contain 50, skull and hyoid apparatus contain 50, thoracic limb contains 90, and pelvic limb contains 96 bones.
But, variation may find in the number of bones in the skeleton of a different breed of dogs. Then the number of bones may vary from 291 – to 321. The variation may occur in the vertebral column and a dog’s limbs.
