Section 05 – Conformation Recording

From ICAR Wiki

1. Introduction

This document contains a description of conformation traits scored in dairy cattle breeds, dual purpose cattle, beef cattle breeds and dairy goats. For the four groups a separate trait list has been established. For the traits, trait definitions are given in wording and with drawings.

Besides giving trait definitions, recommendations are given on improvement and transparency of data collection and monitoring classifiers.

For the dairy, dual purpose and beef cattle breeds a recommendation on scoring conformation defects is given.

2. Linear and composite type traits

2.1 Linear Type Traits

Linear type traits are the basis of all modern type classification systems, and are the foundation of all systems for describing the animal. Linear classification is based on measurements of individual type traits instead of opinions. It describes the degree of trait not the desirability.

Advantages of linear scoring are:

  1. Traits are scored individually.
  2. Scores cover a biological range.
  3. Variation within traits is identifiable.
  4. Degree rather than desirability is recorded.

Standard Traits

The standard traits satisfy the following conditions:

  1. Linear in a biological sense.
  2. Single Trait.
  3. Heritable.
  4. Economic value, direct or indirect with reference to the breeding goal.
  5. Possible to measure instead of score.
  6. Variation within the population.
  7. Each linear trait should describe a unique part of the animal which is not covered by a combination of the other linear traits.


Composite traits and general characteristics

Composite traits

  1. Composite traits are groups of linear traits relating to one specific area.
  2. The individual linear traits are weighted according to economic breeding objectives.
  3. The main composite traits for dairy cattle are: frame including rump, dairy strength, mammary, feet/legs.
  4. The main composite traits for dual purpose breeds are: frame, mammary, feet/legs and muscularity.
  5. The main composite traits for beef breeds are: muscularity, type (breed standard), feet/legs, development and final score.
  6. The main composite traits for dairy goats are: frame, udder, feet/legs and final score.

General characteristics

Type classification programs also include phenotype assessment. These are described as general characteristics or combined traits, which are not linear in a biological sense. A subjective score is given for the desirability of the animal according to the breeding goal.

  • Female animals for dairy and dual purpose breeds are inspected, classified and assigned grades/scores ranging from 50-97 points.
  • For beef breeds animals are inspected, classified and assigned grades/scores ranging from 60-99 points.
  • Dairy goats are inspected, classified and assigned grades/scores ranging from 1-9 points.

The most common scale for mature cows (second or more lactations) in points are described in Table 1.

Table 1. Range of scores for general characteristics or combined traits for cattle of dairy, dual purpose and beef breeds and for dairy goats.

Dairy and dual purpose breeds Beef breeds Dairy goats
Excellent 90 - 97 90 - 99 9
Very Good 85 - 89 85 - 89 7 - 8
Good Plus 80 - 84 80 - 84 4 - 6
Good   79 - 75 79 - 75 2 - 3
Fair/Poor/Insufficient 50 - 74 60 - 74 1


The awarding of classification grades varies in each country depending upon the breeding goals, and therefore classification scores must be considered in the context of the country of inspection.

The final class and score are derived from a breakdown of the main functional areas of the female:

  • For dairy cattle: 1) Frame including Rump, 2) Dairy Strength, 3) Mammary System and 4) Legs/Feet.
  • For dual purpose cattle: 1) Frame, 2) Mammary System, 3) Feet & Legs and 4) Muscularity.
  • For beef breeds: 1) Muscularity, 2) Type (breed standard), 3) Legs/Feet and 4) Development.
  • For dairy goats: 1) Frame, 2) Udder and 3) Legs/Feet.

For the quality of data for beef breeds it is important to score the traits for categories of similar age or sex. For example:

  • Calves at weaning (5-10 months).
  • Heifers: 6 months before calving.
  • Cows: between first and second calving.

For the quality of data of dairy goats it is important to score the traits for categories of similar age or sex.

The weighting of the component breakdown scores should meet the breeding goals in the Country of inspection.

  • It is recommended that for first lactating cows of dairy and dual purpose breeds the range of scores used is 70 - 90 points. The average score is always in the middle of the maximum and minimum a first lactating cow can be awarded.
  • For beef breeds it is recommended that for animals the range of scores used is 60 - 99 points. In the case of the range 60 - 99, the population average should be close to 80.

For dairy goats it is recommended that for animals the range of scores used is 1 - 9 points. The average score is always in the middle of the maximum score and the minimum score the group (for example population within a country) can be awarded. In the case of the range 1 - 9, the population average should be close to 5.

Genetic evaluation of dairy and dual purpose animals

Type Inspection System - Genetic Evaluation

  1. Breeding values for bulls and cows to be based on the classification of cows in the first lactation scored in a herd evaluation system.
  2. In a herd evaluation system all first lactating cows, which have not be previously evaluated, must be scored during the visit of the classifier
  3. Additional classifications to obtain a bull proof may only be possible if completed by the same organisation and daughters are sampled randomly with sufficient number of herd mates (contemporaries) scored during the same visit. A minimum of 5 first lactating cows, which qualify for genetic evaluation, are inspected at the same visit      

Evaluation Model

  1. Modern BLUP evaluation techniques should be used to obtain accurate unbiased evaluations.
  2. Data should be corrected for influencing factors such as age, stage of lactation and season by the model. Classifiers should not make adjustments during scoring.
  3. Corrections for variation between classifiers are required to avoid heterogeneity of variance.
  4. Herd mates are defined as the contemporaries of the evaluated heifers in the same lactation, scored during the same visit by the same classifier.

Publication of Information

  1. Publish bull-proofs around an average of 0 and a genetic standard deviation of 1.0.
  2. Proofs of widespread bulls should be published as bar graphs covering the range between +3 and -3 standard deviations.
  3. Or: Mean of 100 & the standard deviation in the base population where this standard deviation is adjusted to the situation the proofs of cows have a reliability of 100%.
  4. The base of sire and cow evaluation should follow the definition of the production proofs, given by Interbull. This includes a stepwise fixed base that should be renewed every five years. The base is defined by cows born 5 years previously.

Sub-sections

Appendices

Appendix 1: The standard trait definition for Dairy Cattle
Appendix 1: The standard trait definition for Dairy Cattle
Appendix 2: The standard trait definition for Dual Purpose Cattle
Appendix 3: The standard trait definition for Beef Breeds
Appendix 4: The standard trait definition for Dairy Goats
Appendix 5: Relationship between Conformation and Functional Traits
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