Variable
|
No. of dogs tested*
|
% normal hearing
|
% unilateral deafness
|
% bilateral deafnessa
|
Multilevel logistic model**
|
Logistic animal model***
|
---|
Odds ratio (95% CI)†
|
P-value
|
Odds ratio (95% CI)†
|
P-value
|
---|
Sex
| | | | | |
0.044
| |
0.059
|
Male
|
381
|
91.1%
|
5.8%
|
3.1%
|
Reference category
| |
Reference category
| |
Female
|
417
|
86.8%
|
9.1%
|
4.1%
|
1.7 (1.0 to 2.8)
|
0.044
|
1.6 (1.0 to 2.6)
|
0.057
|
Not recorded
|
12
|
75.0%
|
16.7%
|
8.3%
| | | | |
Colour*****
| | | | | |
0.785
| |
0.916
|
Red
|
327
|
88.7%
|
8.0%
|
3.4%
|
Reference category
| |
Reference category
| |
Blue
|
137
|
87.6%
|
7.3%
|
5.1%
|
1.2 (0.6 to 2.7)
|
0.589
|
1.1 (0.5 to 2.3)
|
0.824
|
Blue black tan
|
319
|
88.7%
|
7.5%
|
3.8%
|
0.8 (0.4 to 1.6)
|
0.563
|
0.9 (0.5 to 1.7)
|
0.775
|
Blue tan
|
18
|
88.9%
|
11.1%
|
0.0%
|
0.7 (0.1 to 4.1)
|
0.723
|
0.6 (0.1 to 3.1)
|
0.571
|
Red tan
|
1
|
100.0%
|
0.0%
|
0.0%
| | | | |
Blue black
|
6
|
100.0%
|
0.0%
|
0.0%
| | | | |
Blue mottled
|
1
|
100.0%
|
0.0%
|
0.0%
| | | | |
Red mottled
|
1
|
100.0%
|
0.0%
|
0.0%
| | | | |
Base colour
| | | | | |
0.882
| |
0.885
|
Blue
|
481
|
88.6%
|
7.5%
|
4.0%
|
Reference category
| |
Reference category
| |
Red
|
329
|
88.8%
|
7.9%
|
3.3%
|
1.0 (0.6 to 1.9)
|
0.882
|
1.0 (0.6 to 1.8)
|
0.890
|
Blue black tan
| | | | | |
0.447
| |
0.768
|
No
|
491
|
88.6%
|
7.7%
|
3.7%
|
Reference category
| |
Reference category
| |
Yes
|
319
|
88.7%
|
7.5%
|
3.8%
|
0.8 (0.4 to 1.5)
|
0.447
|
0.9 (0.5 to 1.6)
|
0.775
|
Blue black
|
No
|
804
|
88.6%
|
7.7%
|
3.7%
|
NM
| |
NM
| |
Yes
|
6
|
100.0%
|
0.0%
|
0.0%
| | | | |
Blue tan
| | | | | |
0.688
| |
0.951
|
No
|
792
|
88.6%
|
7.6%
|
3.8%
|
Reference category
| |
Reference category
| |
Yes
|
18
|
88.9%
|
11.1%
|
0.0%
|
1.4 (0.2 to 8.5)
|
0.688
|
1.0 (0.2 to 4.7)
|
0.954
|
Red tan
|
No
|
809
|
88.6%
|
7.7%
|
3.7%
|
NM 2
| |
NM 2
| |
Yes
|
1
|
100.0%
|
0.0%
|
0.0%
| | | | |
Speckled
| | | | | |
0.609
| |
0.726
|
No
|
423
|
88.7%
|
7.3%
|
4.0%
|
Reference category
| |
Reference category
| |
Yes
|
387
|
88.6%
|
8.0%
|
3.4%
|
1.2 (0.7 to 2.1)
|
0.609
|
1.1 (0.6 to 1.9)
|
0.733
|
Mottled
| | | | | |
0.507
| |
0.589
|
No
|
805
|
88.7%
|
7.7%
|
3.6%
|
Reference category
| |
Reference category
| |
Yes
|
5
|
80.0%
|
0.0%
|
20.0%
|
2.4 (0.2 to 33.0)
|
0.507
|
1.9 (0.2 to 20.8)
|
0.593
|
Mask
| | | | | |
0.001
| |
****
|
No
|
185
|
85.4%
|
12.4%
|
2.2%
|
Reference category
| |
Reference category
| |
Left
|
66
|
83.3%
|
10.6%
|
6.1%
|
1.0 (0.4 to 2.4)
|
0.992
|
1.0 (0.4 to 2.3)
|
0.988
|
Right
|
58
|
81.0%
|
12.1%
|
6.9%
|
1.4 (0.6 to 3.3)
|
0.455
|
1.2 (0.5 to 2.9)
|
0.603
|
Bilateral
|
229
|
95.6%
|
3.1%
|
1.3%
|
0.2 (0.1 to 0.5)
|
0.001
|
0.2 (0.1 to 0.5)
|
<0.001
|
Not recorded
|
272
|
87.9%
|
6.6%
|
5.5%
| | | | |
Head spot
| | | | | |
0.767
| |
0.911
|
No
|
439
|
88.8%
|
8.7%
|
2.5%
|
Reference category
| |
Reference category
| |
Yes
|
99
|
89.9%
|
6.1%
|
4.0%
|
0.9 (0.4 to 2.0)
|
0.767
|
1.0 (0.5 to 2.0)
|
0.916
|
Not recorded
|
272
|
87.9%
|
6.6%
|
5.5%
| | | | |
Pigmented body spot
| | | | |
0.034
| |
0.043
|
None
|
430
|
87.4%
|
9.3%
|
3.3%
|
Reference category
| |
Reference category
| |
At least one
|
104
|
95.2%
|
3.8%
|
1.0%
|
0.3 (0.1 to 0.9)
|
0.034
|
0.4 (0.1 to 1.0)
|
0.041
|
Not recorded
|
276
|
88.0%
|
6.5%
|
5.4%
| | | | |
White head/body patches
| | | | |
0.852
| |
0.933
|
No
|
508
|
89.0%
|
8.3%
|
2.8%
|
Reference category
| |
Reference category
| |
Yes
|
27
|
88.9%
|
7.4%
|
3.7%
|
1.1 (0.3 to 4.7)
|
0.852
|
0.9 (0.3 to 3.5)
|
0.937
|
Not recorded
|
275
|
88.0%
|
6.5%
|
5.5%
| | | | |
Sire CHSD status
| | | | | |
0.085
| |
0.205
|
Tested normal
|
502
|
91.4%
|
6.4%
|
2.2%
|
Reference category
| |
Reference category
| |
Unilateral deaf left ear
|
10
|
70.0%
|
20.0%
|
10.0%
|
5.9 (0.8 to 44.0)
|
0.085
|
3.3 (0.5 to 21.1)
|
0.200
|
Unknown
|
298
|
84.6%
|
9.4%
|
6.0%
| | | | |
Dam CHSD status
| | | | | |
0.321
| |
0.402
|
Normal
|
430
|
88.6%
|
8.4%
|
3.0%
|
Reference category
| |
Reference category
| |
Unilateral deaf right ear
|
3
|
66.7%
|
0.0%
|
33.3%
|
4.8 (0.2 to 105.5)
|
0.321
|
3.4 (0.2 to 59.7)
|
0.400
|
Unknown
|
377
|
88.9%
|
6.9%
|
4.2%
| | | | |
- The odds ratios are for having at least one deaf ear rather than normal hearing.
- *No. indicates number.
- ** Multilevel logistic models with dog fitted within litter within kennel of birth. Bolded P-values are overall likelihood ratio test P-values; unbolded P-values are Wald P-values for each coefficient.
- *** Logistic animal (‘threshold’) models using the full pedigree (ie all pedigree data that were available), with dog fitted as a random effect with a numerator relationship matrix. Bolded P-values are overall Wald P-values; unbolded P-values are Wald P-values for each coefficient.
- **** Overall p-value for mask in logistic animal model not calculated.
- ***** Last 5 categories were pooled for analyses.
- † 95% CI indicates 95% confidence interval.
- EX Dogs excluded because 0 dogs or 1 dog in group had hearing loss.
- NM Variable not modelled as no dogs in group had hearing loss.
- NM 2 Variable not modelled as only one dog in red tan group.
- a Some rows do not sum to 100.0% due to rounding.