New traits and composites added to Type Classification
2019 sees the introduction of four new traits in classification as well as three new composites. Meurig James, NBDC Head of Breed Development, explains the upcoming changes.
Dairy cattle breeding changes over time to respond to market requirements. This leads to new or different bloodlines coming to prominence within breeds and inevitably the linear conformation or ‘type’ of cattle changes as a result.
The core role of classification is to record type in cattle and provide composite scores that enable the identification of animals that are capable of a long productive life. As dairy cattle populations change in type then classification sometimes also needs to evolve to record and monitor those changes.
Four new traits
Udder tilt, Height at front end, Loin strength and Thurl position are the four new traits to be scored in heifers and cows – applying across all dairy breeds classified by NBDC, including Holsteins and British Friesians. Udder tilt is a recent phenomenon appearing in dairy cattle, whereby in particular the rear udder sits markedly higher than the fore udder, which is undesirable. Height at Front end and Loin strength are introduced to monitor the skeletal structure, with the aim of promoting sound spine and rump conformation. Thurl position will also be scored to provide more information on rump conformation. These new traits bring the total number of individual traits scored up to twenty four.
Three new composites
Body conformation and Dairy strength are being replaced by three new composites – Dairy Capacity, Rump and Dairy Character. The composite box breakdown of the traits is shown in the table below, as well as the percentage weighting applied to each in the overall classification score. There will therefore now be five composite boxes instead of four.
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NEW HOLSTEIN TYPE CLASSIFICATION SCORING SYSTEM (new traits in bold) |
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Mammary |
Feet and Legs (30%) |
Dairy Capacity (10%) |
Rump |
Dairy Character (10%) |
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> Udder depth > Udder texture > Central ligament > Fore udder attachment > Front teat placement > Rear udder height > Rear udder width > Teat length > Teat position > Udder tilt |
> Foot angle > Rear leg side view > Rear leg rear view > Bone quality > Locomotion |
> Stature > Body depth > Chest width > Height at front end |
> Rump angle > Rump width > Loin strength > Thurl position |
> Angularity |
Overall score
The new traits and composites will not have a major effect on the overall score of most animals and the current overall score classes remain unchanged as per the table below.
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TYPE CLASSIFICATION SCORE |
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90-97 |
Excellent (Ex) |
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85-89 |
Very Good (VG) |
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80-84 |
Good Plus (GP) |
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75-79 |
Good (G) |
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65-74 |
Fair (F) |
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50-64 |
Poor (P) |
If you wish to discuss the new classification system, please contact Meurig James on 07860438510 or Darren Todd at darrentodd@nbdc.uk