It's important for new breeders to understand about those important factors when starting to think and acquire knowledge about genetics of breeding and selecting dogs for breeding pairs. Here's a more in-depth collection of research with sources about inheritability.
Getting our first correct breeding pair is sometimes a costly and painful experience. Many breeders that have been there before us embellish and aggrandize traits of their dogs, and sadly fail to reveal the problems or
issues that might arise, specially diseases that are thought to be transmitted
genetically. It's up to us to investigate and research.
Thankfully, a lot of information can be found on the world wide web and a new breeder does not have to accept many out-dated myths as the "law". We can find out if there is any truth to what is being said! We can question the conclusions made by a breeder that a Sire or a Dam transmitted a conformation trait or behavior trait and in which probability.
From the Behavioral Sciences Department of Palomar College, San Marino California:
"The value of studying genetics is in understanding how we can predict the likelihood of inheriting particular traits. This can help plant and animal breeders in developing varieties that have more desirable qualities. It can also help people explain and predict patterns of inheritance in family lines.One of the easiest ways to calculate the mathematical probability of inheriting a specific trait was invented by an early 20th century English geneticist named Reginald Punnett. His technique employs what we now call a Punnett square. This is a simple graphical way of discovering all of the potential combinations of genotypes that can occur in children, given the genotypes of their parents. It also shows us the odds of each of the offspring genotypes occurring."
How does this relate to dogs?
Abby Dernburg does a wonderful explanation of how Gregor Mendel tried to solve this question and how the views were before Mendel. Most importantly she explains with pictures that when parents of "pure-bred", "in-bred" or "true-bred" and how the the outcome is more predictable and specific traits can be more isolated. She uses very clear visual image that can help even the most confused of beginners.
In her wonderful thesis copy-written in 2008 by Abby Dernburg, University of Berkely which explains with great graphics and pictures which questions: "Do progeny inherit traits from their parents in predictable ways? "
She explains Mendals Laws using graphic of peas. Unfortunately, we dont have the text-book that comes with this text that explains "dihybrid" crosses ( here is a simple explanation), which explains his second law.
she writes:
"It is difficult to overstate the brilliance or significance of Mendel’s insights
•the units of inheritance are “particulate,” not blended
•phenotypes are determined by a combination of two discrete particles, one
from each of the reproductive cells that give rise to an organism
•it is inconsequential whether a particular particle is inherited through the
pollen or the ovum
- that is, both sexes make equal contributions to the progeny
•distinct traits are determined independently of each other
The graphic explanation with photos of the recessive/dominant traits of the Rhodesian Ridgeback litter is very educational. It also showed the association of how the "ridge" on the Rhodesian Ridgeback is caused by a dominant mutation and predisposes to the congenital developmental disorder dermoid sinus. So how to avoid breeding the congenital disorder, while keeping the "ridge" trait? A must read for the aspiring breeder.
How does the apply to behavior traits?
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