Osteopetrosis in Calves
Also known as Metaphyseal Dysplasia or Marble Bone disease
Background on Osteopetrosis
Osteopetrosis, also known as marble bone disease is a skeletal disorder in cattle that causes the bones to be overly dense. The reason the bones become so dense is due to a deficiency in the number/function of osteoclast cells. Osteopetrosis can develop either from the Dam during fetal development or the offspring can inherit the genetic mutation. This disease is most common in Red Angus cattle which are known carriers for the genetic mutation.
Diagnosing Calves with Osteopetrosis
- Have short lower just with impacted molars
- Shortened long bones
- Usually are stillborn calves
- Failure of the bone marrow cavity
- Thickened bones of and around the skull
- Protruding tongue
- Open fontanelle
Newborn calf that has survived the first couple hours of life
Calves that are born with osteopetrosis are usually born as still born calves but if they are born alive they will die within 24 hours of parturition.
A stillborn calf due to osteopetrosis.
In this picture you can see their shorter bottom jaw, which also causes the calf to have impacted molars. The calf also displays the protruding tongue.
A Stillborn Red Angus calf
Most calves will die between 251-272 days into partrurition
Prevention/Treatment
- Genetically inherited mutations, all known Sire carriers should be culled from herd
- Heifer carriers can be kept as long as they are bred with non-carrier Sires(Homozygous dominant)
- No known treatments, all calves should be euthanized that are (op) postive
Genotype
- Homozygous dominant sire(OP free) bred with heterozygous dam will result in:
1. 50 % chance of offspring having carrier allele
2. 50% chance offspring will not have carrier allele and be homozygous dominant
- Breeding heterozygous sire with heterozygous dam will result in:
1. 50% chance the offspring will be a carrier for osteopetrosis
2. 25% chance offspring will be inffected with osteopetrosis
3. 25% chance offspring will be homozygous dominant and not be a carrier
Genetic Transmission
- Non sex-linked
- Autosomal recessive in Red Angus carriers
- Caused by a deletion mutation
- Affects the Bovine gene known as SLC4A2
- Loss of SLC4A2 gene function causes early cell death, which is believed to disrupt acidification if the resorption lacunae
- Research Done by several Animal Scientists at University of Illinois- tested >54,oo base pairs on seven different calves
Opinion
Considering this a lethal disease to calves it is fairly easy to detect a carrier dam or sire. If you have a stillborn calf or a live calf born diagnosed with osteopetrosis it is vital to your herd that you get genetic testing on your bulls and the Dam that produced the osteopetrosis calf. Calves born with osteopetrosis will not recover from this disease, so every calf born with this disease is an automatic production loss. Herd management is the key to a successful operation and diseases like osteopetrosis must be taken serious and culled out of your herd as soon as possible. Its very always report carrier animals to your appropriate breed association.
References
Picture references:
- https://www.google.com/search?q=osteopetrosis+in+cattle+genotype+ratio&rlz=1C1TSNJ_enUS485US485&espv=2&biw=1242&bih=545&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjo5OHW16_MAhVL1WMKHfGlBNsQ_AUIBigB&dpr=1.1#imgrc=ggtVsm_ZL9eWtM%3A
- http://d1jeytwjaq17t7.cloudfront.net/content/dmm/7/1/119/F4.large.jpg
Information References:
- Red Angus Association of America. 2016. web 25 April. 2016/http://redangus.org/genetics/dna-tools/defects/OS
- .A missense mutation accelerating the gating of the lysosomal Cl−/H+-exchanger ClC-7/Ostm1 causes osteopetrosis with gingival hamartomas in cattle. Diseases Models and Mechanisms.2014. web. 24 April. 2016 http://dmm.biologists.org/content/7/1/119
- Meyers, SN, McDaneld TG, Swist SL, Marron BM, Steffen DJ, O’Toole D, O’Connel JR, Beever JE, Sonstegard TS, and Smith TP. A deletion mutation in bovine SLC4A2 is associated with osteopetrosis in Red Angus cattle.BMC Genomics 2010;11(337) http://calfology.com/library/wiki/osteopetrosis
- McGavin, MD and Zachary JF. Pathologic Basis of Veterinary Disease, 4th Ed. Mosby Elsevier, St Louis MO. 2007 http://www.ncbi.nlm.nih.gov/pubmed/20507629