Snorter Dwarfism

What is snorter dwarfism? Snorter dwarfism is a heredity disease that causes a cow to have a smaller nose them normal. It was named “snorter” dwarfism in the late 1940s and 50s because of the sound the calve produces when it breaths. Snorter dwarfism is a simple recessive trait. The phrase simple recessive trait is only visible when the gene is homozygous. AA – normal,Aa – normal, aa – shows the defect.If both members of a gene pair are the same, it is referred to as “homozygous”. If they are different then it is referred to as “heterozygous”.

“Attempts to determine the actual physiological cause of dwarfism were not too successful, although various effects of the dwarf gene were observed which caused the dwarf to differ significantly from the normal.” Says V. G. Dev and J. F. Lasley in the article Growth Hormone Level in the Blood of Dwarf and Normal Hereford Cattle. After all the testing they did Marlow, Rooney and Mestanza (1962), for example, found that the anterior pituitary glands of snorter dwarf cattle possessed growth hormone but in amounts significantly lower than found in the pituitaries of normal cattle.

There are many ways to test for snorter dwarfism for example there is e-rays and blood testing. Taking a sample of the calves blood is the most common one.in the article “ Use of Hematological Techniques in Study of ”Snorter” dwarfism”they used the blood technique,and here are some of the steps of testing blood. “ The blood characteristics analyzed were red cell count, white cell count, white cell differential count, percent hemoglobin, percent packed red cells and fragility of erythrocytes.With the exception of the method for determining erythrocyte fragility, conventional hematological laboratory procedures were used. The fragility technique consisted of introducing 0.4 cc. oxalated blood into a colorimeter tube containing 8 cc. of sodium chloride solution. The saline solution and blood were mixed by inverting the tube five times. The tubes were placed in a rack for 30 minutes to permit complete hemolysis and then centrifuged for ten minutes at 1700 R.P.M. The supernatant fluid was decanted and read in a Klett colorimeter against a distilled water bank. The samples having the higher degrees of hemolysis gave the higher colorimeter reading. The colorimeter reading was the observation for erythrocyte fragility.”

References:

Marlowe, Thomas. “Journal of Animal Science.”Journal of Animal Science. 454-460. Print. Dev, V.G., and J.F. Lasely. “Journal of Animal Science.”Journal of Animal Science. (1969): 384-388. Print. High, Jr., J.W., H.J. Smith, C.M. Kincaid, and C.S. Hobbs. “Journal of Animal Science.” Journal of Animal Science. 1438-1446. Print. Temple, R.S., and l.N. Hazel. “Journal of Animal Science.”Journal of Animal Science. 20 (1961): 459-463. Print.