Fawn Calf Syndrome
- First discovered in Australia in 2001.
- There it was recognized as a heritable disease affecting Angus cattle. In fact it was traced back to the four bull studs in the United States.
- Since then it has been recognized worldwide in Angus cattle.
Description of the Disease
Contractual Arachnodactyly or Fawn Calf Syndrome (FCS) results from an abnormality of skeletal development. Calves generally have a normal birth weight but a variety of symptoms affect them.
- Long and thin legs.
- Contracture of the proximal limbs; specifically the hock and stifle.
- Decreased range of motion in the hind end.
- Most recognizable feature is the malalignment of the spine, resulting in an ached back. This is what gives the disease the name "Fawn Calf" due to them resembling baby deer.
These symptoms range in severity. 10% of cattle affected do not have the ability to stand or walk, which makes them unable to nurse. Without intensive nursing these calves usually die. There are also cases were the diagnosis can be difficult due to degree of symptoms. Often times by the four to six months of age they can appear normal.
Why is this a problem?
What We Know
- Non-lethal autosomal-recessive genetic disease
- Simply inherited
- AA are homozygous dominant and non-carriers
- Aa are heterozygous carrier
- aa are homozygous recessive and affected
Example of Punnet Square and Genotypes
Current Methods of Prevention
- Laboratory DNA tests are available.
- The American Angus Association also has strict testing and registering rules in order to know carriers.
"American Angus Association Contractural Arachnodactyly (CA) Fact Sheet." American Angus Association. 10 Oct. 2013. Web. 29 Apr. 2015. <http://www.angus.org/pub/ca/CAFactSheet.pdf>.
Parish, Dr. Jane, and Dr. Trent Smith. "Managing Genetic Defects in Beef Cattle Herds." Mississippi State University Extension Service, 2010. Web. 29 Apr. 2015. <http://msucares.com/pubs/publications/p2622.pdf>.
"Contractural Arachnodactyly (CA)." Canadian Angus. 26 July 2010. Web. 29 Apr. 2015. <http://www.cdnangus.ca/breed/Contractural_Arachnodactyly.htm>.
Windsor, P., Kessell, A. and Finnie, J. (2011), "Neurological diseases of ruminant livestock in Australia. V: congenital neurogenetic disorders of cattle." Australian Veterinary Journal, 89: 394–401
Whitlock, B.K. ; Kaiser, L. ; Maxwell, H.S. “Heritable bovine fetal abnormalities.”
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