Asthenosphere Asthenosphere, Layer beneath the lithosphere. The asthenosphere is the layer of our planet that lies beneath the lithosphere. It was first named by J. Barrell, a British geologist when he divided the interior of the Earth into three parts. The lithosphere is the outer layer of the Earth that contains crustal plates.
It is wise, however, to have the test repeated by a different laboratory using a different technique (Western Blot). Mother cats with FIV pass antibody to their kittens whether the kittens become infected or not. So positive test results in kittens do not mean they harbor the virus of FIV. If kittens are positive, they need to be retested every two months until they are six months old to see if the test becomes negative. If the test is still positive at six month, they probably have the disease.
As a result of immunodeficiency, most infected cats do not show symptoms and have normal life expectancy, however they are prone to developing other infections and certain types of cancer. A retrovirus, such as FIV, inserts a copy of its genetic material into the DNA of a host cell, where it can replicate. FIV is a lentivirus. a specific type of retrovirus that can take months, or even years to incubate, so the virus is slow moving, capable of lying dormant in the body before causing symptoms.