Spider lamb syndrome

Symptoms

Symptoms have been observed on fetal lambs as early as by the completion of the second gestational trimester. Under normal production circumstances, the lambs usually do not survive past the neonatal period. For this reason, the disease is considered semi-lethal. The disease typically affects the musculo-skeletal system. The clinical signs can include: skeletal abnormalities, twisted or humped spines, facial defects, bent legs, abnormally long legs, flat ribs, and underdeveloped muscles. Due to these symptoms, lambs cannot stand to nurse.

Spider lamb syndrome is untreatable, and in almost all cases, the lambs must be euthanized.

Causes

Spider lamb syndrome is caused by a mutation to the gene for fibroblast growth factor receptor 3 (FGFR3), on ovine chromosome 6. FGFR3 is in the tyrosine kinase receptor family and its function is to restrict the proliferation of cartilage at the growth plates of the long bones: regulating ossification (the conversion of cartilage into bone), limiting skeletal elongation, and thereby ensuring that the limbs are the right length.

References

References

1. [http://www.sheepresearch.co.nz/publication_database/hereditary-chondrodysplasia-spider-syndrome-new-zealand-suffolk-lamb-american Hereditary chondrodysplasia ("spider syndrome") in a New Zealand Suffolk lamb of American origin.], originally published in ''New Zealand veterinary journal'', Volume 43, p.118-22 (1995); by West, DM; Burbidge, H M; Vermunt, J J; Arthur, D G; archived at the International Sheep Research Centre; retrieved July 19, 2012
2. [http://www.smallruminantresearch.com/article/0921-4488%2895%2900722-W/abstract Developmental progression of the Spider Lamb Syndrome] in ''Small Ruminant Research'', Volume 18, Issue 2, Pages 179-184, October 1995, by A.M. Oberbauer, N.E. East, R. Pool, J.D. Rowe, and R.H. BonDurant
3. (2006). "A novel mutation in FGFR3 causes camptodactyly, tall stature, and hearing loss (CATSHL) syndrome". Am J Hum Genet.
4. [http://www.vgl.ucdavis.edu/services/SpiderLamb.php Spider Lamb Syndrome: Introduction] at [[UC Davis School of Veterinary Medicine]]; retrieved July 19, 2012
5. [http://www.ag.ndsu.edu/archive/hettinge/livestock/Archive/spider98sdr.pdf Spider Lamb Syndrome - 1998 Sheep Day Report: The Test for Spider Lamb Syndrome Gene in Sheep] at [[North Dakota State University]]; by Bert Moore, Wes Limesand and Paul Berg; publisher 1998; retrieved July 19, 2012
6. [http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/90228.htm Spider Lamb Syndrome], at the [[Merck Veterinary Manual]]; published 2011; retrieved July 19, 2012
7. Fitch, Gerald. (March 2017). "Spider Syndrome".
8. "spider".
9. [http://www.udifmv.ulg.ac.be/genmol/Department/Publications/Cockett_1999.pdf Localization of the locus causing Spider Lamb Syndrome to the distal end of ovine Chromosome 6], from ''Mammalian Genome'' 10, 35–38 (1999); by N.E. Cockett, T.L. Shay, J.E. Beever, D. Nielsen, J. Albretsen, M. Georges, K. Peterson, A. Stephens, W. Vernon, O. Timofeevskaia, S. South, J. Mork, A. Maciulis, T.D. Bunch; archived at the [[University of Liège]]; retrieved July 19, 2012
10. [http://jas.fass.org/content/84/11/2942.full Enhanced skeletal growth of sheep heterozygous for an inactivated fibroblast growth factor receptor 3], ''Journal of Animal Science'', vol. 84 no. 11 2942-2949; by L. B. Smith, M. R. Dally, R. D. Sainz, K. L. Rodrigue and A. M. Oberbauer
11. [https://www.sciencedirect.com/science/article/pii/092144889500722W Developmental progression of the Spider Lamb Syndrome], by A.M. Oberbauer, N.E. East, R. Pool, J.D. Rowe, and R.H. BonDurant; in ''Small Ruminant Research''; Volume 18, Issue 2, October 1995, Pages 179-184
12. (2006). "A single-base change in the tyrosine kinase II domain of ovine FGFR3 causes hereditary chondrodysplasia in sheep". Animal Genetics.