All Dals on which I have records:
Dals where both parents are bilaterally hearing:
Dals where sire is bi and dam is uni:
Dals where sire is uni and dam is bi:
Dals where both parents are uni:
Combining bi X uni and uni X bi and uni X uni into one group:
I don't feel that the uni X uni data is reliable because of a small sample size (only 26 dogs). Also, I have no idea why I have twice as many data points for dogs with bi sire and uni dam than uni sire and bi dam. Although the numbers no longer show twice the incidence of deafness with one or more uni parents (as when I first analyzed the data), there clearly is a penalty to be paid with these breedings. Note that these are not probabilities, but merely incidence numbers. The reflect a predominance of high quality dogs, since much of the data was acquired at shows, so true incidence levels for the breed overall may well be higher.
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