Protruding Tongue

Currently it is not possible to identify ‘ Protruding Tongue’ carriers by looking for defective Chromosomes by DNA analysis ; however the Belgian Herdbook has calculated the likely incidence of the disease by inspecting all calves at birth (0-4 months), at the point of registration of the calf onto the Belgian Herdbook.

Calves are assesed on a 1 – 3 scale.

1 = No problem

2 = Small signs of a problem

3 = A major the calf cannot suck.

The Prodruding Tongue Index is published when it has achieved an reliability of at least 50%, to have this level of precision on average 110 calves have to be observed from each bull being assessed.

The average value of the Indexes is 100, the higher the index value, the higher the frequency of the defect, expected in the offspring of the sire.




% of defects in offspring















Green Coloured Index – Good

White coloured index - Average

Red Coloured Index – Bad

The above table shows the expected frequencies of the defects in offspring.

Eg. If a bull has an index value of 100, you can expect 10.71% of his calves to show the Protruding Tongue defect, if the index is 80, only 5.42% of his offspring could be expected show the defect.

Bloodlines to be Avoided. (non exhaustive list):

  • Orvet du Bois de Baillonville
  • Cubitus du Pré Rosine
  • Ajusté du Bronheit
  • Lasso vh Kookshof

Bloodlines to be Prefered

  • Bruegel d’Au Chene
  • Ecrin de St Fontaine
  • Baron du Bois Bauloye…

Protruding Tongue is also associated with ‘Jaw Deviation’ and when selecting sires this Index should also be consided. 

Please see the accompanying listing.

download Protruding Tongue Listing June 2013

Acknowledments to the Herd-Book Blanc-Bleu Belge