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AU Sire Catalogue 2016
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the power of breeding for
ntm
we consider
ntm
the best breeding goal in the world, but still people have different preferences and therefo- re may use different breeding objectives. for holsteins the
tpi
index seems to be the most known. differently from
ntm
, where relative weights are defi ned mainly by objective economical modelling, weights in
tpi
are more subjectively defi ned by holstein association usa.
ntm
is a more complete total merit index with many unique traits which are beyond the scope of
tpi
. moreover, some traits having similar names in
tpi
have much more data behind them in
ntm
(such as the fertility index). but what happens with ebvs included in
ntm
if one starts to select holsteins from vikinggenetics using
tpi
? for that purpose we analyzed correlations between nordic ebvs and
tpi
versus
ntm
for all vikingholstein bulls (born in denmark, sweden and finland) listed on www.dairybulls.com (dec 2015), born 2008-2014 (643 sires). the results of the correlation analysis could be interpreted as relative breeding progress for the nordic ebvs if you select sires on
tpi
alternative
ntm
(fig 1). the results showed that vikingholsteins chosen on
tpi
would have superior frame and somewhat higher pro- duction, but only slightly better mammary than those chosen by
ntm
. on the other hand,
ntm
provides much better progress for all
health
and fertility traits along with longevity. better correlation of f&l conformation with
ntm
refl ects that our f&l composite in vikingge- netics is not completely the same as f&l are defi ned in us. still all the traits have positive correlations with both total merit indices. that is because all the bulls are viking bulls and were selected for
ntm
and therefore in general having good fertility and
health
. it is however a good illustration how considerably one will compromise on
health
and fertility without gaining much extra for production if one will consider to select viking holsteins using
tpi
index. don?t compromise on fertility and
health
by selecting viking holsteins on
tpi
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 yield fertility birth index calving index frame feet & legs mammary milkability temperament udder
health
other diseases hoof
health
longevity
ntm
tpi
fig 1 6
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