AASHUDNA

Registered DOGS NSW Breeder of Miniature Smooth Dachshunds

X-ray showing calcifications in a dachshund spine.
X-ray showing calcifications in a dachshund spine.
Important! Copyright © information.

It is important to mention that the text you are about to read is an opinion piece penned by Aashudna Dachshunds, owned by Heather Coles. All the images in this article have been created exclusively by Heather Coles and are protected by copyright ©. Please remember that you need our written permission to reproduce this article or its images. Contact us for more information on obtaining permission.

What do backscores REALLY mean?​

Dachshunds are unfortunately prone to developing IVDD (Intervertebral Disc Disease), which results in debilitating back pain and paralysis that can last for the remainder of their lives. IVDD is a very painful condition for dachshunds, and often their prolonged suffering is compounded by misdiagnosis or incomplete treatment. The exact cause of Dachshund IVDD is not known. However, there are several contributing factors which may include:

  1. Genetics and/or Calcifications,
  2. Structure and physical health
  3. Accidents and/or blows to the lower back region.

What tools are available to breeders to help reduce the risk of IVDD?

Currently, 5 radiographic (x-ray) examinations of the back between the ages of 2 and 4 years old can reveal the number of calcifications and therefore the risk of disc herniation and or prolapse can be estimated.

Results: Disc calcification at 2 years of age was a significant predictor of clinical disk herniation (odds ratio per calcified disk, 1.42; 95% confidence interval, 1.19 to 1.81). https://pubmed.ncbi.nlm.nih.gov/18828719/

What is a disc calcification?

Disc calcification can be described as the body’s attempt to safeguard a damaged or strained disc. When a disc becomes inflamed due to deformation or excessive stress, the body instinctively sends calcium to that specific area in order to aid in the healing process and reduce inflammation. The presence of calcium in the disc can lead to drying out, which in turn triggers inflammation. As a response, the body sends more calcium to the inflamed disc. Over time, this process leads to the encasement and hardening of the disc through the formation of a calcified outer shell.

Due to this process, the disc in the spine becomes stiffer and less flexible over time. Within the disc, there is a gel-like substance called the nucleus pulposus, which is surrounded by layers similar to an onion called the annulus fibrosus. When the calcified disc undergoes water loss from the gel-like substance of the nucleus pulposus, it leads to a decrease in its size. The outer casing of a spinal disc, known as the annulus fibrosus, can become less resilient and prone to damage. As a result, the inner nucleus pulposus may shrink in size, causing the annulus fibrosus to contract and create fractures within its various layers composed of fibrous tissue. The calcified layer surrounding the annulus fibrosus plays a crucial role in safeguarding the intervertebral disc from tears and ruptures by preventing excessive contractions. However, there are instances where this protective function may fail, leading to disc herniation or prolapse.

When a disc herniation or prolapse happens, it can lead to the breaking of a hardened calcified protective shell into small pieces. These fragments often get pushed into the spinal cord and can cause significant damage. It is important to note that it is typically the calcified debris that poses the most damage to the spinal cord during an episode of intervertebral disc disease (IVDD).

Back scoring is a breeder’s tool for risk assessment for the potential for IVDD in dachshunds.

To obtain an X-ray of an adult dachshund’s spine, it is necessary to capture images from various angles. This approach allows the spinal analyst to assess whether the spinal column has degenerated due to water loss within the disc and the formation of calcifications around each disc between each vertebra. In high-risk areas of the spine, disc calcification can lead to additional weakness, causing the disc to herniate. This condition is often referred to as a “slipped disk,” which puts pressure on the spinal cord and nerves. The spinal analyst receives the detailed X-rays and proceeds to count the number of calcifications. Based on this count, the dachshund is assigned a grade ranging from 0 to 3. The ultimate aim is to achieve the lowest possible grade, with a grade of 0 being the most desirable outcome.

Number Calcifications (Backscore)Grade
0 CalcificationGrade 0
1 – 2 CalcificationsGrade 1
3 – 4 CalcificationsGrade 2
5 – 28 CalcificationsGrade 3
Source : https://www.dachshund-ivdd.uk/screening-for-ivdd/what-do-the-scores-mean/

Regardless of the backscore test results, backscoring will not provide a definitive answer as to whether or not your dachshund has IVDD. However, breeders utilise these score results to analyse and compare various aspects of the spine, enabling them to make more informed decisions about breeding. By combining this information with the pedigree history of known IVDD occurrences, breeders are able to select the most suitable mates for breeding in order to reduce the number of calcifications in the offspring of the selected pairings.

It is our mission to provide healthy, quality Dachshunds in Australia. We place a strong focus on the prevention of IVDD. We back-score our breeding stock at the age of 2 years old and this has been very successful in helping us keep IVDD at bay.

What are the reported findings of IVDD between the different backscore grades?

Back Score GradeOdds Ratio
Grade 0 versus Grade 1For every dachshund with a grade 0 which experiences IVDD, 3.3 dachshunds with a grade 1 will experience IVDD.
Grade 0 versus Grade 2For every dachshund with a grade 0 which experiences IVDD, 5.3 dachshunds with a grade 2 will experience IVDD.
Grade 0 versus Grade 3For every dachshund with a grade 0 which experiences IVDD, 17.9 dachshunds with a grade 3 will experience IVDD.
Grade 1 versus Grade 2For every dachshund with a grade 1 which experiences IVDD, 1.6 dachshunds with a grade 2 will experience IVDD.
Grade 1 versus Grade 3For every dachshund with a grade 1 which experiences IVDD, 5.4 dachshunds with a grade 3 will experience IVDD.
Grade 2 versus Grade 3For every dachshund with a grade 2 which experiences IVDD, 3.4 dachshunds with a grade 3 will experience IVDD.
Source: https://actavetscand.biomedcentral.com/articles/10.1186/s13028-014-0089-4/tables/3

Dogs with five or more calcified discs (grade 3) have 11 times greater risk of disc herniation compared to dogs with fewer than five calcifications (grade 0-2).

Bruun, C.S., Bruun, C., Marx, T. et al. Breeding schemes for intervertebral disc disease in dachshunds: Is disc calcification score preferable to genotyping of the FGF4 retrogene insertion on CFA12?. Canine Genet Epidemiol 7, 18 (2020). https://doi.org/10.1186/s40575-020-00096-6

Are the areas of the spine that are more at risk of herniation and/or prolapse?

Yes.

According to the study data provided by Rohdin, C., Jeserevic, J., Viitmaa, R. et al., it has been found that 30% of all cases of intervertebral disc disease (IVDD) occur in the T12-T13 disc location. Out of the 100 dachshunds that were x-rayed, 34 of them had a calcification in this specific location. Interestingly, out of those 34 dachshunds, 30 of them (88.24%) went on to develop IVDD in the same T12-T13 location.

The majority of IVDD disc prolapse, about 77%, tends to occur in four specific disc locations: T11-12, T12-13, T13-L1, and L1-2. These locations are located in the middle of the back and can be found at the end of the rib cage.

The thoracic lumbar region of the spine, specifically from T1 to T13, accounts for 69% of all disc herniation or prolapse. However, the segments from T1 to T10 are supported by the rib cage and crucial ligaments, making them less likely to be affected unless under extreme circumstances.

According to a recent study, the overall risk of cervical or neck issues is estimated to be approximately 6%. However, it is important to note that some claims made outside this study have suggested a higher risk of around 15%.

Based on the findings of this study, a notable portion (25%) of disc herniation or prolapse cases were identified in the lumbar L1-L7 region. This particular area is known to lack support, making it more vulnerable to such conditions. Recent studies, conducted independently of this study, have compared thoracic length to lumbar length in dogs. These studies have shown that dogs with a higher lumbar-to-thoracic ratio are at an increased risk of experiencing disc herniation or prolapse in the lumbar region.

This study did not include observations on L7-S1. However, it is worth noting that IVDD type II at this level tends to develop slowly and progressively. It is more commonly observed in older individuals and can be triggered or aggravated by external factors like over-exercising or exposure to cold weather. In the case of Dachshunds, anti-inflammatories and crate rest might help improve their condition in the L7-S1 location.

According to researchers, it is recommended to prioritise breeding dogs with back scores below 5 (grade 0-2). However, it may be worth considering the potential risks associated with breeding in higher-risk locations as well.

Yes, breeders should be aware that there is no perfect solution when it comes to breeding. It is important to carefully select and breed the desired attributes for future generations. This involves targeting and reducing areas at higher risk of calcifications leading to the development of IVDD, addressing immediate health concerns and taking preventive measures. It also focuses on enhancing and maintaining the dachshund’s temperament, ensuring the improvement of breed conformation, and ensuring that they are well-suited for their intended function.

Back scoring is a valuable tool that gives us valuable information in advance, often before we decide to include a dachshund in our breeding program. This allows us to make informed decisions and ensure the quality and suitability of the dogs we use.

Some breeders opt to breed low-scoring dogs with other low-scoring dogs, while others may choose to concentrate on higher-risk areas. For instance, when addressing the issue of prolapses in the T11-L1 locations where they are most common, it would be beneficial to utilise a sire without calcifications in that specific area. This can help effectively eliminate or enhance this particular region within their selected lines.

It is important to adopt a realistic mindset when it comes to breeding miniature smooth dachshunds with consistently low scores. It typically takes multiple generations of careful breeding and selection to achieve the desired results. At present, Australia has a very limited number of miniature smooth dachshunds that are currently of breeding age and have undergone back-scoring evaluation. Following the strict recommendation of breeding dogs based on their grades can pose challenges. It may not be feasible to only breed grade 2 dogs with grade 1 or 0 dogs, grade 1 dogs with grade 0 dogs, and grade 0 dogs with another grade 0 dachshund while eliminating all grade 3’s from breeding programs. Data collected from other ANKC breeders across Australia by Aashudna Dachshunds reveals that approximately 44% of MS Dachshunds have scores indicating more than five calcifications (grade 3). It is important to consider genetic diversity when making decisions about breeding dogs. Taking a more balanced and thoughtful approach is necessary when considering the removal of certain miniature smooth dachshunds from the gene pool. Completely eliminating them may result in a loss of genetic diversity. It is important to prioritise the preservation of genetic variation among the breed.

When breeders don’t have access to back screening data for IVDD (Intervertebral Disc Disease), they rely on their expertise, knowledge of pedigrees, and understanding of the family history of the condition to make well-informed breeding choices. This involves utilising their best judgement and considering all available information to ensure the health and well-being of future generations.

Breeding advice obtained from Dachshund Health UK https://www.dachshund-ivdd.uk/screening-for-ivdd/what-do-the-scores-mean/

The Australian National Dachshund Council Health Database currently contains a small number of 5 backscored, breeding-aged, miniature smooth dachshunds sires, with results ranging from grade 0 to grade 2. Out of these sires, 4 are connected to our kennel.

As of the amendment date of this article, 20-09-2023. http://www.nationaldachshund.com/index.php/health-and-welfare/surveys/

Would you complete this breeding?

An example of a fictitious back score breeding pair. Left, 4 calcifications (grade 2) and right, 6 calcifications (grade 3) are bred together and the following is considered.

🔎 Analyzing the Backscore Results of Our Fictional Pairing! 📊

Curious about the outcomes? Let’s take a closer look at the anticipated results and evaluate if this breeding can be deemed successful in terms of “back health.”

The mentioned pair successfully produced a litter of 6 puppies. One parent has 4 calcifications (grade 2), while the other parent has 6 calcifications (grade 3). Let’s analyse the results of these 6 puppies below.

To facilitate a better understanding, let’s label the puppies in a specific order based on the image above. Starting from the top row and moving from left to right, we have offspring 1, offspring 2, and offspring 3. Then, on the bottom row, again moving from left to right, we have offspring 4, offspring 5, and offspring 6.

According to researchers, it is recommended to retain dachshunds with less than 5 calcifications (grade 0-2) in a breeding program based on backscores. Out of the 6 offspring, 5 of them meet this criteria. These five dachshunds have made significant progress in reducing their risk by carefully selectively breeding their parents to target high-risk areas in the back.

Share your thoughts on this extraordinary fictional pairing and let us know if you think it was a successful breeding in terms of “back health.” We love hearing your insights! 💬🤔

#BreedingResults #FictionalPairing #BackscoreAnalysis

Conclusion

IVDD (Intervertebral Disc Disease) is indeed a complex issue that requires careful consideration from breeders. It’s not as simple as selecting the lowest scored dachshund. Multiple factors need to be taken into account, such as genetic diversity, temperament, improvement of conformation, and other health ailments. One tool that can assist breeders in analyzing and comparing different aspects of a dachshund’s spine is backscoring tests. These tests can provide valuable information when combined with knowledge of known IVDD occurrences in the pedigree history. While they may not definitively determine whether or not a dog has IVDD, they help breeders make more informed breeding decisions. By using this information to select suitable mates, breeders aim to reduce the number of calcifications in the offspring resulting from those pairings. This approach allows for better management and reduction of IVDD risk within the breeding program. It’s important for breeders to consider all these facets and weigh their options carefully to promote healthier outcomes for future generations of dachshunds.

Important! Copyright © information.

It is important to mention that the text you are about to read is an opinion piece penned by Aashudna Dachshunds, owned by Heather Coles. All the images in this article have been created exclusively by Heather Coles and are protected by copyright ©. Please remember that you need our written permission to reproduce this article or its images. Contact us for more information on obtaining permission.