Clean Run - November 2017 - 59

breeders) had no reason to believe
that ETOs might be caused by something other than physical pain or training. No one even considered that the
cause(s) of ETOs could have a heritable
component. Thus, there was no reason
to be concerned about it when selecting breeding stock. But now that we
understand more about ETOs, those
who are breeding performance dogs
that will be required to jump should
be concerned.
Today, most breeds in agility are still
bred for a purpose other than agility,
which creates a problem if that other
purpose does not involve jumping. It
becomes very difficult to determine
which sire and dam will produce nice
agility prospects! Even in breeds that
excel in agility, performance dog
breeders are the minority or they
do not focus solely on agility. Many
breeds are bred primarily for conformation or companionship, with only a

Emmetropia
Myopia
Hyperopia
Not Tested

small percentage bred strictly for performance. Many pups that enter agility
are offspring of dogs that have never
jumped a jump in their lives. Some
breeds participate in more than one
performance sport. A breeder that focuses on producing top herding dogs
is understandably not going to be concerned about jumping ability.
Many breeders are still unaware that
a problem even exists. For those who
are not breeding performance dogs
and selling them as agility prospects,
it probably doesn't matter. But it is
very important that performance dog
breeders understand what ETOs are
and the impact they might have on the
future of their puppies. These breeders need to educate themselves and
evaluate their dogs. Most breeders are
unaware of the risk factors for ETOs
and that they are presumed to be inherited, or they are aware and do not
want to admit it. The unusually high

incidence of ETOs in some lines (and
some breeds) very strongly supports
the heritability of ETO causes, and the
current recommendation is that breeders (and puppy buyers) err on the side
of caution.
The current thinking is that breeding
an affected individual is inadvisable. It
is also not advisable to breed an unaffected individual that has produced
affected pups in one or more litters,
particularly when bred to a different
individual each time, or an unaffected
individual that has siblings, or other
close relatives with ETOs. Obviously,
much more data needs to be collected
to ascertain which breeds have higher
incidence of one or more of the risk
factors. In one study, conducted to
determine whether the distribution of
naturally occurring myopia in Labrador
Retrievers has a genetic component,
the results indicated that indeed there
was a signi´Čücant genetic component.3

From: A Canine Model of Inherited Myopia: Familial Aggregation of Refractive Error in Labrador Retrievers.
Invest. Ophthalmol. Vis. Sci.. 2008;49(11):4784-4789. doi:10.1167/iovs.08-1828

This diagram shows the relationships between the 134 dogs in the study, including the mating loops. The sample included
62 females and 72 males, with 92 dogs having yellow, 37 black, and 5 unknown coat color. Although the diagram shows dogs from
37 litters, it does not show all dogs in each litter. Refractive error was obtained from an average of 42% of dogs from each litter
(only those whose refractive errors were determined are shown).
November 17 | Clean Run

59



Table of Contents for the Digital Edition of Clean Run - November 2017

Contents
Clean Run - November 2017 - Cover1
Clean Run - November 2017 - Cover2
Clean Run - November 2017 - Contents
Clean Run - November 2017 - 4
Clean Run - November 2017 - 5
Clean Run - November 2017 - 6
Clean Run - November 2017 - 7
Clean Run - November 2017 - 8
Clean Run - November 2017 - 9
Clean Run - November 2017 - 10
Clean Run - November 2017 - 11
Clean Run - November 2017 - 12
Clean Run - November 2017 - 13
Clean Run - November 2017 - 14
Clean Run - November 2017 - 15
Clean Run - November 2017 - 16
Clean Run - November 2017 - 17
Clean Run - November 2017 - 18
Clean Run - November 2017 - 19
Clean Run - November 2017 - 20
Clean Run - November 2017 - 21
Clean Run - November 2017 - 22
Clean Run - November 2017 - 23
Clean Run - November 2017 - 24
Clean Run - November 2017 - 25
Clean Run - November 2017 - 26
Clean Run - November 2017 - 27
Clean Run - November 2017 - 28
Clean Run - November 2017 - 29
Clean Run - November 2017 - 30
Clean Run - November 2017 - 31
Clean Run - November 2017 - 32
Clean Run - November 2017 - 33
Clean Run - November 2017 - 34
Clean Run - November 2017 - 35
Clean Run - November 2017 - 36
Clean Run - November 2017 - 37
Clean Run - November 2017 - 38
Clean Run - November 2017 - 39
Clean Run - November 2017 - 40
Clean Run - November 2017 - 41
Clean Run - November 2017 - 42
Clean Run - November 2017 - 43
Clean Run - November 2017 - 44
Clean Run - November 2017 - 45
Clean Run - November 2017 - 46
Clean Run - November 2017 - 47
Clean Run - November 2017 - 48
Clean Run - November 2017 - 49
Clean Run - November 2017 - 50
Clean Run - November 2017 - 51
Clean Run - November 2017 - 52
Clean Run - November 2017 - 53
Clean Run - November 2017 - 54
Clean Run - November 2017 - 55
Clean Run - November 2017 - 56
Clean Run - November 2017 - 57
Clean Run - November 2017 - 58
Clean Run - November 2017 - 59
Clean Run - November 2017 - 60
Clean Run - November 2017 - 61
Clean Run - November 2017 - 62
Clean Run - November 2017 - 63
Clean Run - November 2017 - 64
Clean Run - November 2017 - 65
Clean Run - November 2017 - 66
Clean Run - November 2017 - Cover3
Clean Run - November 2017 - Cover4
http://www.nxtbook.com/nxtbooks/cleanrun/1119
http://www.nxtbook.com/nxtbooks/cleanrun/1019
http://www.nxtbook.com/nxtbooks/cleanrun/0919
http://www.nxtbook.com/nxtbooks/cleanrun/0819
http://www.nxtbook.com/nxtbooks/cleanrun/0719
http://www.nxtbook.com/nxtbooks/cleanrun/0619
http://www.nxtbook.com/nxtbooks/cleanrun/0519
http://www.nxtbook.com/nxtbooks/cleanrun/0419
http://www.nxtbook.com/nxtbooks/cleanrun/0319
http://www.nxtbook.com/nxtbooks/cleanrun/0219
http://www.nxtbook.com/nxtbooks/cleanrun/0119
http://www.nxtbook.com/nxtbooks/cleanrun/1218
http://www.nxtbook.com/nxtbooks/cleanrun/1118
http://www.nxtbook.com/nxtbooks/cleanrun/1018
http://www.nxtbook.com/nxtbooks/cleanrun/0918
http://www.nxtbook.com/nxtbooks/cleanrun/0818
http://www.nxtbook.com/nxtbooks/cleanrun/0718
http://www.nxtbook.com/nxtbooks/cleanrun/0618
http://www.nxtbook.com/nxtbooks/cleanrun/0518
http://www.nxtbook.com/nxtbooks/cleanrun/0418
http://www.nxtbook.com/nxtbooks/cleanrun/0318
http://www.nxtbook.com/nxtbooks/cleanrun/0218
http://www.nxtbook.com/nxtbooks/cleanrun/0118
http://www.nxtbook.com/nxtbooks/cleanrun/1217
http://www.nxtbook.com/nxtbooks/cleanrun/1117
http://www.nxtbook.com/nxtbooks/cleanrun/1017
http://www.nxtbook.com/nxtbooks/cleanrun/0917
http://www.nxtbook.com/nxtbooks/cleanrun/0817
http://www.nxtbook.com/nxtbooks/cleanrun/0717
http://www.nxtbook.com/nxtbooks/cleanrun/0617
http://www.nxtbook.com/nxtbooks/cleanrun/0517
http://www.nxtbook.com/nxtbooks/cleanrun/0417
http://www.nxtbook.com/nxtbooks/cleanrun/0317
http://www.nxtbook.com/nxtbooks/cleanrun/0217
http://www.nxtbook.com/nxtbooks/cleanrun/0117
http://www.nxtbook.com/nxtbooks/cleanrun/1216
http://www.nxtbook.com/nxtbooks/cleanrun/1116
http://www.nxtbook.com/nxtbooks/cleanrun/1016
http://www.nxtbook.com/nxtbooks/cleanrun/0916
http://www.nxtbook.com/nxtbooks/cleanrun/0816
http://www.nxtbook.com/nxtbooks/cleanrun/0716
http://www.nxtbook.com/nxtbooks/cleanrun/0616
http://www.nxtbook.com/nxtbooks/cleanrun/0516
http://www.nxtbook.com/nxtbooks/cleanrun/0416
http://www.nxtbook.com/nxtbooks/cleanrun/0316
http://www.nxtbook.com/nxtbooks/cleanrun/0216
http://www.nxtbook.com/nxtbooks/cleanrun/0116
http://www.nxtbook.com/nxtbooks/cleanrun/1215
http://www.nxtbook.com/nxtbooks/cleanrun/1115
http://www.nxtbook.com/nxtbooks/cleanrun/1015
http://www.nxtbook.com/nxtbooks/cleanrun/0915
http://www.nxtbook.com/nxtbooks/cleanrun/0815
http://www.nxtbook.com/nxtbooks/cleanrun/0715
http://www.nxtbook.com/nxtbooks/cleanrun/0615
http://www.nxtbook.com/nxtbooks/cleanrun/0515
http://www.nxtbook.com/nxtbooks/cleanrun/0415
http://www.nxtbook.com/nxtbooks/cleanrun/0315
http://www.nxtbook.com/nxtbooks/cleanrun/0215
http://www.nxtbook.com/nxtbooks/cleanrun/0115
http://www.nxtbook.com/nxtbooks/cleanrun/1214
http://www.nxtbook.com/nxtbooks/cleanrun/1114
http://www.nxtbook.com/nxtbooks/cleanrun/1014
http://www.nxtbook.com/nxtbooks/cleanrun/0914
http://www.nxtbook.com/nxtbooks/cleanrun/0814
http://www.nxtbook.com/nxtbooks/cleanrun/0714
http://www.nxtbook.com/nxtbooks/cleanrun/0614
http://www.nxtbook.com/nxtbooks/cleanrun/0514
http://www.nxtbook.com/nxtbooks/cleanrun/0414
http://www.nxtbook.com/nxtbooks/cleanrun/0314
http://www.nxtbook.com/nxtbooks/cleanrun/0214
http://www.nxtbook.com/nxtbooks/cleanrun/0114
http://www.nxtbook.com/nxtbooks/cleanrun/1213
http://www.nxtbook.com/nxtbooks/cleanrun/1113
http://www.nxtbook.com/nxtbooks/cleanrun/1013
http://www.nxtbook.com/nxtbooks/cleanrun/0913
http://www.nxtbook.com/nxtbooks/cleanrun/0813
http://www.nxtbook.com/nxtbooks/cleanrun/0713
http://www.nxtbook.com/nxtbooks/cleanrun/0613
http://www.nxtbook.com/nxtbooks/cleanrun/0513
http://www.nxtbook.com/nxtbooks/cleanrun/0413
http://www.nxtbook.com/nxtbooks/cleanrun/0313
http://www.nxtbook.com/nxtbooks/cleanrun/0213
http://www.nxtbook.com/nxtbooks/cleanrun/0113
http://www.nxtbook.com/nxtbooks/cleanrun/1212
http://www.nxtbook.com/nxtbooks/cleanrun/1112
http://www.nxtbook.com/nxtbooks/cleanrun/1012
http://www.nxtbook.com/nxtbooks/cleanrun/0912
http://www.nxtbook.com/nxtbooks/cleanrun/0812
http://www.nxtbook.com/nxtbooks/cleanrun/0712
http://www.nxtbook.com/nxtbooks/cleanrun/0612
http://www.nxtbook.com/nxtbooks/cleanrun/0512
http://www.nxtbook.com/nxtbooks/cleanrun/0412
http://www.nxtbook.com/nxtbooks/cleanrun/0312
http://www.nxtbook.com/nxtbooks/cleanrun/0212
http://www.nxtbook.com/nxtbooks/cleanrun/0112
http://www.nxtbook.com/nxtbooks/cleanrun/1211
http://www.nxtbook.com/nxtbooks/cleanrun/1111
http://www.nxtbook.com/nxtbooks/cleanrun/1011
http://www.nxtbook.com/nxtbooks/cleanrun/0911
http://www.nxtbook.com/nxtbooks/cleanrun/0811
http://www.nxtbook.com/nxtbooks/cleanrun/0711
http://www.nxtbook.com/nxtbooks/cleanrun/0611
http://www.nxtbook.com/nxtbooks/cleanrun/0511
http://www.nxtbook.com/nxtbooks/cleanrun/0411
http://www.nxtbook.com/nxtbooks/cleanrun/0311
http://www.nxtbook.com/nxtbooks/cleanrun/0211
http://www.nxtbook.com/nxtbooks/cleanrun/0111
http://www.nxtbook.com/nxtbooks/cleanrun/1210
http://www.nxtbook.com/nxtbooks/cleanrun/1110
http://www.nxtbook.com/nxtbooks/cleanrun/1010
http://www.nxtbook.com/nxtbooks/cleanrun/0910
http://www.nxtbook.com/nxtbooks/cleanrun/0810
http://www.nxtbook.com/nxtbooks/cleanrun/0710
http://www.nxtbook.com/nxtbooks/cleanrun/0610
http://www.nxtbook.com/nxtbooks/cleanrun/0510
http://www.nxtbook.com/nxtbooks/cleanrun/0410
http://www.nxtbook.com/nxtbooks/cleanrun/0310
http://www.nxtbook.com/nxtbooks/cleanrun/0210
http://www.nxtbook.com/nxtbooks/cleanrun/0110
http://www.nxtbook.com/nxtbooks/cleanrun/1209
http://www.nxtbook.com/nxtbooks/cleanrun/1109
http://www.nxtbook.com/nxtbooks/cleanrun/1009
http://www.nxtbook.com/nxtbooks/cleanrun/0909
http://www.nxtbook.com/nxtbooks/cleanrun/0809
http://www.nxtbook.com/nxtbooks/cleanrun/0709
http://www.nxtbook.com/nxtbooks/cleanrun/comp-demo
http://www.nxtbook.com/nxtbooks/cleanrun/0609
http://www.nxtbook.com/nxtbooks/cleanrun/0509
http://www.nxtbook.com/nxtbooks/cleanrun/0409
http://www.nxtbook.com/nxtbooks/cleanrun/0309
http://www.nxtbook.com/nxtbooks/cleanrun/0209
http://www.nxtbook.com/nxtbooks/cleanrun/0109
http://www.nxtbook.com/nxtbooks/cleanrun/1208
http://www.nxtbook.com/nxtbooks/cleanrun/1108
http://www.nxtbook.com/nxtbooks/cleanrun/1008
http://www.nxtbook.com/nxtbooks/cleanrun/0908
http://www.nxtbook.com/nxtbooks/cleanrun/0808
http://www.nxtbook.com/nxtbooks/cleanrun/0708
http://www.nxtbook.com/nxtbooks/cleanrun/0608
http://www.nxtbook.com/nxtbooks/cleanrun/0508
http://www.nxtbook.com/nxtbooks/cleanrun/0408
http://www.nxtbook.com/nxtbooks/cleanrun/0308
http://www.nxtbook.com/nxtbooks/cleanrun/0208
http://www.nxtbook.com/nxtbooks/cleanrun/0108
http://www.nxtbook.com/nxtbooks/cleanrun/1207
http://www.nxtbook.com/nxtbooks/cleanrun/1107
http://www.nxtbook.com/nxtbooks/cleanrun/1007
http://www.nxtbook.com/nxtbooks/cleanrun/0907
http://www.nxtbook.com/nxtbooks/cleanrun/0807
http://www.nxtbook.com/nxtbooks/cleanrun/0707
http://www.nxtbook.com/nxtbooks/cleanrun/0607
http://www.nxtbook.com/nxtbooks/cleanrun/0507
http://www.nxtbook.com/nxtbooks/cleanrun/0407
http://www.nxtbook.com/nxtbooks/cleanrun/0307
http://www.nxtbook.com/nxtbooks/cleanrun/0207
http://www.nxtbook.com/nxtbooks/cleanrun/0107
http://www.nxtbook.com/nxtbooks/cleanrun/1206
http://www.nxtbook.com/nxtbooks/cleanrun/1106
http://www.nxtbook.com/nxtbooks/cleanrun/1006
http://www.nxtbook.com/nxtbooks/cleanrun/0906
http://www.nxtbook.com/nxtbooks/cleanrun/0806
http://www.nxtbook.com/nxtbooks/cleanrun/0706
http://www.nxtbook.com/nxtbooks/cleanrun/0606
http://www.nxtbook.com/nxtbooks/cleanrun/0506
http://www.nxtbook.com/nxtbooks/cleanrun/0406
http://www.nxtbook.com/nxtbooks/cleanrun/0306
http://www.nxtbook.com/nxtbooks/cleanrun/0206
http://www.nxtbook.com/nxtbooks/cleanrun/0106
http://www.nxtbookMEDIA.com