Designer
"Teddy Bear" Puppy Network!
AKA Shichons
What
is a Teddy Bear aka zuchon?
A
teddy bear's registered breed is called a Zuchon, a hybrid cross
between a
AKC Bichon Frise - AKC Shih Tzu.
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Heterosis is a term used in genetics and selective breeding. The term heterosis, also known as hybrid vigor or outbreeding enhancement, describes the increased strength of different characteristics in hybrids; the possibility to obtain a genetically superior individual by combining the virtues of its parents.
A mixed-breed dog Heterosis is the opposite of inbreeding depression,
which occurs with increasing homozygosity. The term often causes controversy,
particularly in terms of the selective breeding of domestic animals,
because it is sometimes believed that all crossbred animals are genetically
superior to their parents; this is true only in certain circumstances
: when a hybrid is seen to be superior to its parents, this is known
as hybrid vigor. When the opposite happens, and a hybrid inherits traits
from their parents that makes them unfit for survival, the result is
referred to as outbreeding depression.
The dominance hypothesis attributes
the superiority of hybrids to the suppression of undesirable recessive
genes from one parent by dominant genes from the other. It attributes
the poor performance of inbred strains to loss of genetic diversity,
with the strains becoming purely homozygous at many loci.
Certain combinations of genes that can be obtained by crossing two strains
are advantageous in the hybrid vigor.
