The Institute of Canine Biology
  • HOME
  • Blog
  • Courses
    • COI BootCamp (FREE!)
    • Basic Population Genetics (FREE)
    • The Science of Canine Husbandry
    • Managing Genetics For the Future >
      • Syllabus - Managing Genetics for the Future
    • The Biology of Dogs (Open Reg )
    • DNA For Dog Breeders >
      • Syllabus - DNA for Dog Breeders
      • Open Reg - DNA For Dog Breeders
    • Understanding Hip & Elbow Dysplasia >
      • Open Reg - Understanding Hip & Elbow Dysplasia
    • Genetics of Behavior & Performance >
      • Syllabus - Genetics Behavior & Performance
      • Open Reg - Genetics of Behavior & Performance (Open Reg)
    • Strategies for Preservation Breeding >
      • Open Reg - Strategies for Preservation Breeding
    • Group Discounts
    • MORE FREE COURSES >
      • Quickie Genetics (Free!)
      • Heredity & Genetics (Free!)
      • Useful Genetics (Free!)
      • Basic Genetics Videos
  • Breed Preservation
    • Breed Status
    • Breeding for the future >
      • BFF Breed Groups
    • The "Elevator Pitch"
    • What's in the Gene Pool?
    • The Pox of Popular Sires
    • What population genetics can tell us about a breed
    • What population genetics can tell you...Tollers & Heelers
    • How to use kinship data
    • Using EBVs to breed better dogs >
      • How population size affects inbreeding
      • EBV Examples
    • How to read a dendrogram
    • Global Pedigree Project >
      • The Database
    • Finding the genes without DNA
    • How to read a heat map
  • Health Data
    • Bloat (Purdue Study)
    • Body Condition Score >
      • % Dysplastic vs BCS
    • Breed Comparions
    • Cancer
    • Cardiac
    • Cataracts
    • Caesareans
    • Deafness
    • Degenerative Myelopathy
    • Elbow Dysplasia
    • Epilepsy
    • Genetic Diversity
    • Genetic Diversity (MyDogDNA)
    • Hip Dysplasia >
      • Hip Dysplasia (Hou et al 2013)
    • Inbreeding Effects
    • Inbreeding (Gubbels)
    • Inbreeding (Dreger)
    • Lifespan
    • Litter size
    • Metabolic
    • mtDNA
    • Orthopedic
    • Mode of Inheritance
    • Patella Luxation
    • Thyroid
    • Portosystemic shunt
    • Purebred vs Mixed (UC Davis)
    • Purebred vs Mixed Breed (Bonnett)
    • Spay & Neuter Effects
    • Calboli et al 2008
    • Hodgman (1963)
    • Scott & Fuller (1965)
    • Stockard: Purebred crosses
    • Summers (2011)
  • Projects
    • How To Interpret Breed Analyses
    • Afghan Hound
    • More details about the Toller study
    • Belgian Tervuren >
      • Belgian Terv p2
      • Belgians- why population size matters
    • Bernese Mountain Dog
    • Boxer
    • Brussels Griffon
    • Bullmastiff
    • Canaan Dog >
      • Canaan analyses
    • Cesky Terrier >
      • Cesky genetic history
    • Chinook
    • Curly-coated Retriever
    • Doberman
    • Entelbucher Mountain Dog
    • Flatcoat Retriever
    • French Bulldog
    • German Shorthair
    • Golden Retriever >
      • Golden Retriever Pedigree Charts
    • Irish Water Spaniel >
      • IWS (6 Nov 17)
    • Labrador Retriever
    • Manchester Terrier
    • Mongolian Bankhar >
      • Research Updates
      • Bankhar 1
    • Norwegian Lundehund
    • Plummer Terrier
    • Otterhound
    • Portuguese Water Dog >
      • Portuguese Water Dog (pt 2)
    • Ridgeback
    • Schipperke
    • Standard Poodle >
      • The Problem With Poodles
      • 3poodle pedigree charts
      • 3Poodle Wycliff dogs
      • Poodle Genetics
    • Tibetan Spaniel
    • Tibetan Mastiff
    • West Highland White Terrier
    • Whippet
    • Wirehaired Pointing Griffons
    • UK KC Graphs >
      • UK KC Breed Status
      • UK Groups
      • KC Gundogs
      • KC Hounds
      • KC Terriers >
        • Terriers (select breeds)
      • KC Pastoral
      • KC Toys
      • KC Working
      • KC Utility
      • Australian KC
    • Breed outcrossing programs
  • Resources
    • Genetics Databases
    • Stud Books >
      • American Kennel Club stud books
      • Field Dog stud books
      • The Kennel Club (UK)
    • Learn
    • Videos about dog genetics
    • The Amazing Things Dogs Do! (videos) >
      • Livestock Management
      • Livestock guarding
      • Transportation, exploration, racing
      • Conservation & wildlife management
      • Detection Dogs
      • Medicine & Research
      • Entertainment
      • AKC/CHF Podcasts
    • Read & Watch
    • Bookshelf
  • Preventing Uterine Inertia

Bigger puppies develop hip dysplasia

9/16/2015

 
By Carol Beuchat PhD
Although we think of hip dysplasia (HD) as a "large breed problem", a small dog - the Pug - is right at the top of the OFA rankings. In fact, I have argued in a previous post that that it's not the size of the dog, but the "robustness" of the dog that seems to have the best association with ranking on the OFA "hip list".

I also pointed out that there was clear evidence that food consumption affected the risk of developing HD in an experiment done by Purina. Labrador Retriever puppies raised on a restricted diet weighed less than their litter mates as adults, they developed signs of dysplasia much later in life, and they also lived longer. Clearly, how much the dogs were fed from puppy to adult affected the risk of developing dysplastic hips.

But is the effect due to growth rate or weight?
Picture
There are clearly differences among breeds in growth rates. This is a graph of the growth curves of 12 breeds of dogs that cover the range in adult body size from Papillon to Mastiff. The large breeds are substantially heavier than the smaller ones by 2 or 3 weeks after birth, and the trajectory of their growth is exponential for about the first 8 months. While the small breeds reach adult body mass by 6-8 months, the larger breeds don't attain adult body weight before 1 year and the largest among them continue to put on weight for up to 18 months.
Picture
Hawthorne et al 2004
Picture




So, growth rate is linked to adult body size, and dogs that grow faster will weigh more, so it's hard to experimentally separate the effects of food consumption and weight.

But we can look at the effect of size without the confounding effect of food consumption if we look at newborn puppies. A study of Newfoundlands, Labradors, Leonbergers, and Irish Wolfhounds followed dogs from birth until up to 9 years (Vanden Berg-Foels et al 2006). They found that the weight of puppies at birth was affected by litter size: smaller litters had puppies that weighed more at birth. Furthermore, these larger pups had a higher risk of abnormalities or lesions of the hip cartilage by 8 months. This is despite the fact that the pups that were smaller at birth had exponential "catch-up" growth, so that by 12 days there were no longer differences in weight due to litter size.
Picture
Vanden Berg-Foels et al 2006.


The more puppies weighed at birth, the more likely they were to have abnormalities or lesions of the cartilage on the head of the femur by the time they were 8 months old. Also, for pups of a specific size, males had a higher risk of abnormalities of lesions than females.

So a male puppy weighing more than 0.4 kg at birth, or a female weighing more than 0.5 kg, had a greater than 50% risk of developing hip abnormalities. 

This experiment suggests that it is the weight of the puppy very early in life, and not growth rate, that is the significant factor in the development of HD.

As the authors of this study point out, heavier puppies could challenge the capacity of the immature connective tissues and skeleton for support. If this allows some laxity of the head of the femur, the contact area over which force is distributed would be reduced, putting greater stress on the areas of contact. As the weight of the animal continues to increase with growth, a less than perfect fit of the head of the femur in the hip socket could produce a viscous cycle of damage and greater laxity that could eventually manifest as dysplastic hips.

They conclude that "These results support the hypothesis that increased body weight during the critical early postnatal period was sufficient to alter the course of hip development and result in measureable degenerative changes at adulthood."

So we're left with these thoughts:
  • Puppies from larger litters weigh less at birth
  • Puppies that weigh less at birth grow faster and catch up with the larger pups
  • Puppies from smaller litters weigh more at birth, don't grow as fast as pups from larger litters, and are more likely to show degenerative changes in the hip joint when they get older

The bottom line:
  • The risk of hip dysplasia is related to how much a puppy weighs when it is born.

Inbreeding causes inbreeding depression, which results in smaller litters.
Smaller litters have larger puppies.
Larger puppies are more likely to develop hip dysplasia.
Hmmmmm.

Join our Citizen Science Project!

We have been trying to solve the puzzle of hip dysplasia for decades. Have we been looking for answers in the wrong places? 

ICB is planning a Citizen Science project to study hip dysplasia in dogs. If you're planning on having a litter of puppies in the near future, you can join us! We will be recording the weight of the puppies, how much they eat, how fast they grow, and a few other things might provide the information we need to figure out how to reduce or even eliminate hip dysplasia in dogs. We will need a lot of data for many different breeds, both large and small, so we need your help!

We will need to all of the study participants to be up to speed on what is already known about hip dysplasia from previous studies like this one. To do this, we have organized a course that will start in October that all of the participants need to enroll in. It will last about 8 weeks, and you will learn about anatomy, development, genetics, biomechanics, and much more to lay the foundation for the project. After the course is over we will continue working with those participating in the study to organize the protocol for data collection.

That course is scheduled to start on 1 October and is open to everyone whether you are participating in the study or not.

You can register from the "Courses" tab on the ICB website. We hope to see you there!
  • Hawthorne AJ, D Booles, PA Nugent, G Gettinby, and J Wilkinson. Weight changes during growth in puppies of different breeds. Journal of Nutrition 134: 2027S-2030S.

  • Vanden Berg-Foels WS, RJ Todhunter, SJ Schwager, and AP Reeves. 2006. Effect of early postnatal body weight on femoral head ossification on set and hip osteoarthritis in a canine model of developmental dysplasia of the hip. Pediatric Research 60: 549-554.


Don't miss a post - subscribe to our blog!

Enter your email address:

Delivered by FeedBurner


To learn more about the genetics of dogs, check out
ICB's online courses.
******************************

Visit our Facebook Groups


ICB Institute of Canine Biology
...the latest canine news and research

ICB Breeding for the Future
...the science of animal breeding 


Comments are closed.

    Archives

    January 2025
    November 2022
    July 2022
    May 2022
    April 2022
    March 2022
    February 2022
    November 2021
    October 2021
    December 2020
    January 2020
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    October 2017
    August 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    September 2016
    August 2016
    July 2016
    June 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    February 2014
    December 2013
    October 2013
    September 2013
    July 2013
    March 2013
    July 2012
    April 2012

    Categories

    All
    Behavior
    Border-collie
    Herding

Blog

News


About Us

Contact Us








Copyright © 2012-2017 Institute of Canine Biology
Picture
Picture