Genetic Evaluations Glossary

GLOSSARY OF TERMS

ALL OFFICIAL ME AVERAGE: an average calculated by USDA using completed and records in progress.
Records are converted to a mature equivalent (see explanation below) basis. If a doe has multiple records, the
mature equivalents (ME) from all records are all used in this calculation.

AR: stands for Advanced Registry. Does on DHIR test can be recognized as AR, and are awarded a star
(*M), by meeting qualifying milk and/or butterfat levels outlined in the ADGA Guidebook. Bucks qualify, and are
awarded a plus (+B or ++B), by virtue of their sons and daughters. Specific qualifications for the AR status are
found in the ADGA Guidebook.

BEST OFFICIAL RECORDS AVERAGE: an average calculated from the highest record (whether a qualifying
record or not) of each daughter in this sire’s file. These are actual records only.

CDCB ACRONYMS:  H = number of herds; D = number of daughters; L = number of
lactations; R = reliability; Predicted Transmitting Abilities for milk, PTAM; butterfat, PTAF; percent
butterfat, PTA%; protein, PTAP; percent protein, PTA%P; percentile ranking within the breed.

ESTIMATED TRANSMITTING ABILITY (ETA): an estimation of an animal’s potential genetic worth. ETAs are
calculated using the Production Type Indexes (PTI) of the sire and dam of a young animal. They are used to
evaluate and rank bucks in the ADGA Sire Development Program. ETAs are expressed as 2:1 (emphasis on
production) and 1:2 (emphasis on type) ratios. (A brochure entitled “THE ADGA SIRE DEVELOPMENT
PROGRAM“, which includes detailed information on ETAs and PTIs, is available at the ADGA website,
adga.org.)

LINEAR APPRAISAL: a program designed to evaluate 14 (13 primary and 1 secondary) individual type traits
from one biological extreme to the other. Scored on a scale from 1-50, these evaluations, together with the
final score, are used by USDA to calculate PTATs. The actual scores can also be used to aid with herd
management decisions, and for advertising and promotion. Additional evaluations are made on eight (seven
for bucks) structural traits. A booklet, entitled “LINEAR APPRAISAL SYSTEM FOR DAIRY GOATS” is
available online at the member’s portion of the ADGA website. This booklet provides a detailed explanation of
the Linear Appraisal program, and has illustrations of the primary and secondary traits, excluding stature.

MATURE EQUIVALENT (ME): records that are standardized for days in milk (305), twice-a-day milking,
freshening between January and March, and a mature age of 36 months. They allow for an accurate and
unbiased comparison of records.

PREDICTED TRANSMITTING ABILITY (PTA): genetic evaluation for a specific trait; milk (M), butterfat (F),
percent butterfat (%), protein (P), percent protein (%P), and final score for type (FS). (NOTE: The FS on the
CDCB type proof refers to the PTA for type, the FS on the current appraisal line for either the doe or buck is in
reference to their actual final score from the Linear Appraisal program.) PTAs are calculated using information
from DHI production testing, and the ADGA Linear Appraisal programs.  Yield PTA’s are expressed in pounds, and Type PTA’s are expressed in standard deviations.

PRODUCTION TESTING: a milk testing program available through Dairy Herd Improvement Association
(DHIA). Members can choose between DHI and DHIR test. Records made on DHI are official with DHIA, and
will be used in CDCB production summaries, but are not recognized by ADGA. To receive recognition by
ADGA, members need to be enrolled on DHIR (R = Registry) test. Records printed  on Performance Pedigrees are DHIR records. Also, Breed Leader records must be made on DHIR test. Consult the ADGA Guidebook for more information on the Production Testing
programs.

PRODUCTION TYPE INDEX (PTI): an index calculated by combining genetic evaluations for production and
type. To get a PTI calculation, a doe must have at least one completed DHI production record and be
evaluated in the ADGA Classification and/or Linear Appraisal program. A buck must have USDA summaries
for both production and type. PTIs are expressed as 2:1 (emphasis on production) and 1:2 (emphasis on type)
ratios. Bucks need 5 production daughters and 3 type daughters.

RELIABILITY: the accuracy of the PTA expressed as a percentage (%). The higher the reliability percentage,
the more accurate the proof, and the less susceptible it is to large changes when new information is added.

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