Dogs have a total of 26 ribs, organized into 13 pairs. Each rib is attached to the spine and the sternum, forming a protective ribcage around vital organs such as the heart and lungs. This structure is crucial for respiratory function and overall health.

Rib Anatomy

• Pairs of Ribs: Dogs possess 13 pairs of ribs, totaling 26 ribs.
• Attachment: Ribs connect to the thoracic vertebrae at the back and to the sternum at the front, creating a sturdy framework.
• Function: The ribcage protects internal organs and aids in breathing by allowing expansion during inhalation.

Chest Structure

• The chest, or thorax, is bound by the ribs, sternum, and vertebrae.
• Variations in chest shape (deep, narrow, broad) can affect a dog’s health and physical capabilities
• A chest that is too far below the elbow is just as ‘faulty’ as the chest which is too shallow (or too far above the elbow).

The ribcage should be deep enough to accommodate all the vital organs but not so deep or barrel shaped that it interferes with the movement of the elbow  The bottom of dog’s ribcage should be slightly above or just even with the elbow.

• All ribcages should have the proper length rib and proper bone to cartilage ratio.
• The more correct the rib, the more lung capacity, stamina and endurance.
• Proper spring, curve of ribs should complement the dog’s purpose.
  • Bully breeds have greater spring that Sighthounds.
• Elliptical shape is correct for all breeds at different degrees.
• Exception: Achondroplastic breeds like Dachshund and Basset, the chest will be well below the elbow.

Risks:

Anytime the ribcage shape limits the lung capacity, and thus stamina, it will impede any performance or working dog’s potential.

• Barrel-ribbed or round chest is Incorrect for all breeds.
• Slab-sided is Incorrect for all breeds.
  • Exception: Bedlington Terrier.

Herring gut refers to a specific physical condition in dogs characterized by flat ribs that lack sufficient spring from the spine.

This condition is often associated with dogs that have a shallow chest structure, making them appear less robust in their ribcage formation. The term is derived from the shape of herring fish, which have a similar flat rib structure.

Key Characteristics

• Flat Ribs: Dogs with herring gut have ribs that do not curve outward adequately.
• Shallow Chest: This condition is typically seen in breeds with a naturally shallow chest, affecting their overall appearance and sometimes their health.

Implications

• Health Considerations: While herring gut itself is not a disease, it can be associated with certain health issues related to respiratory capacity and overall body structure.

Sternum is too short. Normally the sternum should reach the 9^th rib and run parallel to the ground.  If it is shorter than that, the dog is herring gutted.

• Reduces lung capacity, endurance and stamina, as there is not enough room to permit full expansion of heart and lungs.
• This also provides inadequate protection for internal organs, which causes serious structural issues for performance and working dogs.
• This can impede the abilities of any dog which is worked hard for extended periods of time (jogging, agility, herding, hunting, etc.).

A barrel-chested dog has a wide, rounded ribcage that gives it a robust appearance. 

This type of chest is characterized by a chest that appears almost globular when viewed from the front, with a straight top and bottom.

Barrel-chested dogs typically have broader shoulders and a more muscular build compared to other chest types.

Characteristics of Barrel-Chested Dogs

• Shape: The ribcage is wide and deep, creating a visually chest-heavy look.
• Structure: The top and bottom of the chest are reasonably straight and even, contributing to a sturdy appearance.
• Breeds: Common examples include Bulldogs and Basset Hounds, which are bred for strength and stability rather than speed.

Comparison with Other Chest Types

• Deep-Chested Dogs: These dogs have a taller, narrower ribcage, suited for running and endurance, such as Greyhounds.
• Round-Chested Dogs: Most dogs fall into this category, having a chest that is neither deep nor barrel-shaped.

When the chest is too wide, the upper arm is prohibited  from swinging freely alongside the chest.  This impeded upper arm movement diminishes the dog’s speed and length of stride.

• It can also create toeing in and rolling out of the shoulder, just as too deep of a chest can.

The prosternum is a key anatomical feature in dogs, located at the front of the rib cage. It serves as the most forward projection of the rib cage, contributing to the overall structure and balance of the dog’s chest.

Specifically, the prosternum is the top part of the sternum, which connects the rib cage and plays a crucial role in the dog’s posture and movement.

Key Characteristics

• Location: Positioned at the front of the rib cage, jutting out ahead of the shoulder joint.
• Function: Acts as an anchor point for the rib cage, helping to define the chest structure and contributing to the dog’s forward balance and strength.
• Importance: A well-defined prosternum can indicate good conformation in dog breeds, particularly in show dogs.

This needs to be sufficient enough to allow for proper muscle attachment from the upper arm, which creates stability and strength in the upper arm.

• Without this it will cause a sloppy forward motion and instability on landings from jumps.
• Similar to loose elbows in that it can lead to the same kinds of injuries for performance dogs.

Eventual wear and tear in the upper arm will likely result in arthritis.

A prosternum that is too far forward in a dog can indicate a structural abnormality. The prosternum is the most forward projection of the rib cage, and its position is crucial for proper thoracic structure and function. When it protrudes excessively, it may lead to:

• Altered Chest Shape: This can affect the overall appearance of the dog and may be associated with conditions like pectus excavatum or pectus carinatum, where the chest is either indented or protruding.
• Breathing Difficulties: An abnormal prosternum position can reduce the space available for the heart and lungs, potentially leading to respiratory issues.
• Congenital Issues: Such deformities are often congenital, meaning they develop during the dog’s growth and can be hereditary.

Dog pigeon chest, also known as pectus carinatum, is a congenital condition where the dog’s sternum protrudes outward, creating a noticeable bulge in the chest area. This deformity can affect any breed, although it is more common in certain types.

Characteristics

• Appearance: The chest appears pointed rather than curved due to the abnormal growth of the sternum and ribs.
• Breathing: In some cases, it may impact respiratory efficiency, although many dogs adapt well.

Causes

• Congenital: Often present at birth, it can develop during growth.
• Acquired: Rarely, it may develop due to trauma or other health issues.

There are several reasons, including the breastbone being shorter than the ideal and characterized by a relative absence of prosternum or too much or exaggerated prosternum. Extremes in either direction will cause some weakness.

• When the prosternum protrudes to the extent it creates a shelf, muscle attachment will be limited.
• Muscle attaching from the upper arm to ribcage are improper, which results in the same sloppy front movement that is seen when the front is set too far forward.
• Can affect the neck and head carriage, muscles that run down the front of the neck attach to the ribcage in the same area as the muscles from the upper arm.
• Improper attachment diminishes muscle strength.

Risks:

Any degree of this causes more susceptibility to injuries when landing from jumps. 

A slab-sided dog has a rib cage that is flat and lacks curvature. This condition is characterized by ribs that are narrow and do not have the typical arch or roundness, which can restrict the dog’s lung capacity and overall movement.

Slab-sidedness is often seen as undesirable in many breeds, particularly those that require agility, as it can hinder their ability to maneuver effectively.

Characteristics of Slab-Sidedness

• Rib Structure: Ribs are flat with little to no curvature.
• Chest Depth: The chest is deeper at the sternum but not broad, leading to a narrow appearance.
• Impact on Performance: This conformation can affect a dog’s ability to perform tasks, especially in breeds that need to navigate tight spaces.

Implications

• Health Concerns: A slab-sided structure may indicate potential respiratory issues due to reduced lung capacity.
• Breed Standards: Many breed standards discourage slab-sidedness, emphasizing the importance of a well-rounded rib cage for optimal health and performance.

Occurs when the ribs are flat with almost no spring. 

• Incorrect for all breeds
• Exception: Bedlington Terrier

Risks:

Disadvantage in working dogs that require stamina, including Sled dogs, Hunting dogs, Lure Coursing, Agility.

The term “dog wasp waist” refers to a specific anatomical feature observed in certain dog breeds. This term is often used to describe a very slender or narrow waist, similar to the shape of a wasp’s body.

In dogs, this can be indicative of a lean physique, which is often seen in breeds that are bred for agility or speed.

Characteristics of Dog Wasp Waist

• Anatomy: The waist is narrower than the chest and hips, creating a streamlined appearance.
• Breeds: Commonly seen in breeds like Greyhounds and Whippets, which are built for running.
• Health Implications: A pronounced wasp waist can be a sign of good fitness, but excessive thinness may indicate health issues or malnutrition.

Importance

• Performance: A lean waist can enhance agility and speed in athletic dogs.
• Aesthetics: Many dog enthusiasts appreciate the sleek appearance of dogs with a wasp waist, as it is often associated with breed standards in show dogs
• Less impact on lung capacity than herring gut, however both are serious faults in all breeds that require stamina and endurance.
• Both issues diminish lung capacity, fluidity, and elasticity of stride.
• This will predispose these dogs to back injuries.

Dog heart-shaped ribs refer to a specific anatomical feature of certain dog breeds. 

This term typically describes the shape of the rib cage, which can resemble a heart in some dogs, particularly those with a more rounded or barrel-shaped chest.

Characteristics of Heart-Shaped Ribs

• Shape Variations: Dogs can have different rib shapes, including oval, round, and heart-shaped. The heart-shaped rib cage is often broader and more rounded, providing ample space for the heart and lungs.
• Breeds: Breeds with a heart-shaped rib cage often include those with a stocky build, such as Bulldogs and Boxers.

The bony part of the rib is too short and cartilage is too long.  The lower portion of the chest is too narrow and has too much give.

• Dogs with a heart-shaped rib cage may have different physical capabilities compared to those with narrower rib shapes, affecting their stamina and agility.
• These ribs lack attachment for the upper arm and makes a sloppy front motion, which makes the dog more susceptible injury when jumping.

A shallow chest in dogs refers to a chest structure that is not deep enough, which can affect their overall health and performance.

Impact on Health

• Heart and Lung Efficiency: A shallow chest limits the capacity of the heart and lungs, which can reduce endurance and overall stamina.
• Physical Stability: When the chest is positioned above the elbow, it can affect how the upper arm connects to the chest, potentially compromising the stability of the dog’s front assembly.

Breathing Considerations

• Shallow Breathing: Dogs with a shallow chest may also exhibit shallow breathing, which can indicate various health issues, including respiratory infections or heart disease.
• Monitoring: It’s important to monitor a dog’s breathing patterns, as changes can signal underlying health problems.

The depth of chest should reach the elbow in most breeds.

• When the chest is above the elbow, it affects the way the upper arm ties into the chest and do diminishes stability of the front assembly.
• Decreases lung capacity, stamina and endurance.
• Exception: Ibizan standard calls for the deepest part of the chest to be inches behind the elbow.

Risks:

Agility dogs are more likely to hit the ribs when the land from jumps and can “jam them”.

A deep chest in dogs refers to a specific anatomical feature where the rib cage is elongated and extends lower than the elbows when the dog is standing. 

This characteristic is commonly found in larger, working breeds such as the Great Dane, Doberman Pinscher, and Boxer.

Characteristics of Deep-Chested Dogs

• Anatomy: The deep chest allows for increased thoracic volume, which can accommodate larger lungs and a more powerful heart.
• Breeds: Common deep-chested breeds include Greyhounds, Boxers, and German Shepherds.

Health Considerations

• Bloat Risk: Deep-chested dogs are at a higher risk for conditions like gastric dilatation-volvulus (GDV), commonly known as bloat, which can be life-threatening.
• Care Tips: Owners should be aware of feeding practices and exercise routines to mitigate health risks associated with deep-chested dogs.

Chest should reach the elbow. When it reaches too far below the elbow, the upper arm is prevented from moving back and forth across the cartilage on the lower part of the chest. 

• It will run into the curve of the rib bone so the dog has to roll the upper arm forward rather than pulling in straight forward.
• This movement has the tendency to turn the front feet inward.
• Exception: Achondroplastic breeds standards call for increased depth.