Genetic Proof Terminology Explained

The letters, numbers and acronyms on a proof sheet can be complicated. Here, we break down the meaning and explanation of the proof indexes, traits, and terminology.

SELECTION INDEXES

We know that every farm is unique. So, we help every farm approach genetic selection with a process that’s customized to fit their operation. We focus on three key questions to help streamline the process of setting and implementing a genetic strategy that matches where you’re at and where you want to go.

Each question helps address one of three genetic plan ‘buckets.’ The amount of emphasis you put on the traits within each bucket sums to 100% of your customized genetic plan.

Industry-formulated genetic indexes can certainly fit your farm’s current situation and future goals. But to know whether that is the case, you must understand what is included in each selection index.

When you know what’s included, you can more effectively evaluate if the index truly matches your farm’s goals.

Customized Breeding Goals

• A customized genetic plan, separate from industry indexes

• Can be developed in partnership between a farm and their Alta advisor

• Can evolve to fit each farm’s needs, and are popular among progressive US dairies

• These are four preset indexes in Alta Bull Search that can serve as a starting point for a customized genetic plan

Production + Balance | A Customized Genetic Plan

Production + Health | A Customized Genetic Plan 

Balance | A Customized Genetic Plan

Industry Indexes

TPI (Total Production Index)

• An industry index calculated by the Holstein Association USA (HA-USA)
• Offers a balanced approach to selection for production, health and conformation
• Most recent update: April 2026

Merit Indexes

• Includes NM$ (Net Merit), CM$ (Cheese Merit), FM$ (Fluid Merit), and GM$ (Grazing Merit)
• Industry Indexes calculated by the Council on Dairy Cattle Breeding (CDCB)
• Describe expected lifetime profit per cow as compared to the base population
• Each of the four indexes is designed to fit a specific type of farm or milk market
• NM$ is the most common of the four merit indexes
• Most recent update: April 2025

NM$ (Net Merit)

CM$ (Cheese Merit)

FM$ (Fluid Merit)

GM$ (Grazing Merit)

Production Traits & Terms

CFP

Combined Fat and Protein

PRel

Percent reliability of a sire’s production proof

PTAM (Predicted Transmitting Ability for Milk)

PTA Milk predicts the expected milk production of future mature daughters, in pounds, in comparison to other cows of the breed born in the same base year. Shown as pounds of milk an animal is expected to produce above or below the average of its herdmates.

PTAF (Predicted Transmitting Ability for Milk Fat)

PTA Fat predicts the expected milk fat production of future mature daughters, in pounds and %, in comparison to other cows of the breed born in the same base year. Calculated in pounds and as a percentage.

PTAP (Predicted Transmitting Ability for Milk Protein)

PTA Protein predicts the expected milk protein production of future mature daughters, in pounds and %, in comparison to other cows of the breed born in the same base year. Calculated both in pounds and as a percent.

Health & Efficiency Traits & Terms

CA$ (Calving Ability Subindex)

Included in NM$, but not calculated directly as its own index. It combines the four calving traits, DCE, DSB, SCE, and SSB along with the economics associated with difficult calvings or calves born dead. Net Merit integrates all four traits 3.3% of Total NM$. TPI focuses on DCE and DSB 3.0% of Total TPI.

• SCE (Sire Calving Ease): The percentage of births of bull’s calves that are considered difficult in first lactation animals

• DCE (Daughter Calving Ease): The percentage of a bull’s daughters who have difficult births during their first calving

• SSB (Sire Stillbirth): The percentage of a bull’s calves that are born dead to first lactation animals

• DSB (Daughter Stillbirth): The percentage of a bull’s daughters who give birth to a dead calf in their first lactation

CCR (Cow Conception Rate)

Updated August 2026

Cow Conception Rate is defined as the proportion of inseminations that result in pregnancy for an individual cow, based on outcomes for up to the first seven inseminations. CCR PTA predicts the expected difference in conception rate of an animal’s daughters as lactating cows relative to the breed base. A bull’s CCR of 1.0 implies that daughters of this bull are 1% more likely to become pregnant during that lactation than daughters of a bull with an evaluation of 0.0.

• The 2026 CCR revision adds a days-in-milk covariable to the model

• Improves genetic selection for successful conception in lactating cows

• Supports reduced breeding costs and fewer inseminations per pregnancy

• Complements Daughter Pregnancy Rate by focusing on conception success rather than time to pregnancy

• Enhances reproductive efficiency in modern herd management systems

• PTA Range of Active A.I. Bulls

  • Holstein CCR: -8.3 to +7.3

  • Jersey CCR: -4.1 to +5.1

  • Brown Swiss CCR: -3.6 to +2.9

DIA (Resistance to Diarrhea)

New August 2026 for Holsteins and Jerseys

• Represents the expected resistance of an animal’s offspring to calfhood diarrhea in a herd with average management conditions

• PTAs for DIA evaluations are expressed in percentage points of resistance above or below the breed average. Larger, positive values are more favorable, indicating greater resistance

• Holstein bulls will range from -2.6 to +2.6

DPR (Daughter Pregnancy Rate)

Updated August 2026

Daughter Pregnancy Rate is defined as the percentage of non-pregnant cows that become pregnant during each 21-day cycle, relative to the breed base. A DPR of ‘1.0’ implies that daughters from this bull are 1% more likely to become pregnant during that estrus cycle than a bull with an evaluation of zero. Each increase of 1% in PTA DPR equals a decrease of 4 days in PTA days open.

• The 2026 DPR revision changes the voluntary waiting period (VWP) used in the calculation of DPR from a fixed 50-day VWP with a 20-day grace period to herd-level and lactation group-specific values.

• Improves reproductive efficiency by reducing days open

• Supports better herd reproductive performance and sustainability

• Contributes to greater longevity and lifetime productivity

• Provides a standardized reproductive performance metric that can be used across herds and management systems

• PTA Range of Active A.I. Bulls

  • Holstein DPR: -5.3 to +5.7

  • Jersey DPR: -3.6 to +5.0

  • Brown Swiss EFC: -1.6 to +3.0

EFC Early First Calving

Updated August 2026

Early First Calving PTA predicts an animal’s genetic ability to influence the age at which its daughters have their first calving, relative to the breed base. EFC is defined and calculated as the number of days from a heifer’s birth to her first calving. A positive value means a heifer is more likely to calve younger. A negative value means a heifer is more likely to have an older age at first calving.

• Supports early reproductive maturity in replacement heifers

• Contributes to improved lifetime productivity and herd efficiency

• Reduces nonproductive days prior to first lactation

• Complements conception-based reproductive performance traits by capturing timing of reproductive onset

• The 2026 revision moves the calculation of EFC to a single-trait model.

• PTA Range of Active A.I. Bulls

  • Holstein EFC: -16.9 to +8.4

  • Jersey EFC: -13.1 to +10.1

  • Brown Swiss EFC: -9.4 to +8.9

FE (Feed Efficiency Index)

A composite index that includes production traits, body weight composite and residual feed intake to reflect better feed utilization. Included in TPI, it’s not published as its own index.

FI (Fertility Index)

Updated August 2024

Combines several reproductive components all into one index. It’s included in the TPI formula, but not published as its own index. It includes the following traits, in order by weight within the index:

• Daughter Pregnancy Rate (DPR = 40%)

• Cow Conception Rate (CCR = 40%)

• Heifer Conception Rate (HCR = 10%)

• Early First Calving (EFC = 10%)

FSAV (Feed Saved)

The FSAV predicted transmitting ability (PTA) represents the expected pounds of feed saved per lactation based on evaluations for Body Weight Composite (BWC) and Residual Feed Intake (RFI). Expressed in pounds of feed saved per lactation above or below the breed average. It combines Body Weight Composite (BWC) and Residual Feed Intake (RFI) evaluations based on actual, rather than expected feed intake data. Larger, positive values are more favorable.

• FSAV trait was introduced in December 2020 and incorporated into NM$ in August 2021 for Holsteins.

FSC (First Service to Conception)

New August 2026

First Service to Conception is a reproductive performance trait that measures an animal’s genetic ability to achieve a successful conception in fewer days after the first insemination. Useful for producers who select voluntary waiting periods on a cow basis and want cows to get pregnant as quickly as possible after the first breeding without focusing on how many services it takes.

• PTA Range of Active A.I. Bulls

  • Holstein FSC: -24.8 to +20.7

  • Jersey FSC: -12.5 to +15.2

  • Brown Swiss FSC: -7.8 to +9.2

GL (Gestation Length)

For service sires, the Gestation Length (GL) PTA’s represent the influence the service sire is expected to have on the number of days his mates (the cow carrying his calf) carry his calves during their pregnancies. Indication of the length that a sire’s mate carries a calf, in days, as compared to the average of the breed

• In grazing or seasonal calving herds, differences in gestation length may help concentrate calvings into a specified period

• In all operations, gestation length may help herds schedule dry dates, pinpoint expected calving dates and manage the maternity pen

• Increase understanding correlated effects of GL on other traits such as calving ease, stillbirth, and age at first calving

• GL trait was introduced in August 2017

HCR (Heifer Conception Rate)

Updated August 2026

Heifer Conception Rate is defined as the proportion of inseminations that result in pregnancy for an individual heifer, based on outcomes for up to the first seven inseminations. HCR PTA predicts the expected difference in conception rate of an animal’s daughters as maiden heifers relative to the breed base. An HCR of 1.0 implies that daughters of this bull are 1% more likely to become pregnant as a heifer than daughters of a bull with an evaluation of 0.0.

• The 2026 HCR revision updates the model to account for service sire breed, mating type, and short cycling (an insemination that takes place 10 to 17 days after the previous insemination).

• PTA Range of Active A.I. Bulls:

  • Holstein HCR: -5.3 to +4.6

  • Jersey HCR: -3.4 to +4.2

  • Brown Swiss HCR: -5.6 to +3.7

HLIV Heifer Livability

Heifer Livability predicts the difference in female young offspring expected to remain alive between 2 days after birth and 18 months of age, expressed in percentage points from the breed base.

HRel

Percent reliability for a sire’s health trait proof numbers

HTH$ Health Trait Subindex

Calculated by CDCB, included in TPI and NM$, but not released as its own index. It is made up of the following traits, in order of weight within the index. For each of the following traits, a positive number equates to better resistance against the given health condition.

• MAST (Resistance to Mastitis): Measures a cow’s resistance to contract mastitis

• METR (Resistance to Metritis): Measures a cow’s ability to resist contracting metritis

• DA (Resistance to Displaced Abomasum): Measures a cow’s ability to resist having a displaced abomasum

• RETP (Resistance to Retained Placenta): Measures a cow’s ability to resist having a retained placenta

• KETO (Resistance to Ketosis): Measures a cow’s ability to resist contracting ketosis

• MFEV (Resistance to Milk Fever or Hypocalcemia): Measures a cow’s resistance to contract milk fever at calving

LIV Cow Livability

A measure of the cow’s ability to stay alive in the herd. Data is a subset of Productive life, but accounts for whether a cow was sold for a cull price or died on the farm.

MSPD (Milking Speed)

Milking Speed (MSPD) in Holsteins provides dairy producers with an opportunity to further optimize parlor efficiency. Genetic evaluations for male and female Holsteins predict the average pounds of milk an animal’s offspring will give per minute in a conventional milking system. Evaluations are expressed on a phenotypic scale with a Holstein breed average of 7 pounds per minute.

• Faster-milking cows can be selected for, allowing more cows to be milked through the parlor in the same period of time.

• Slower-milking cows can be selected against, improving herd consistency and limiting disruptions to the milking routine.

• Greater parlor throughput is a more efficient use of labor and facilities.

• New trait August 2025 for Holsteins

• Active A.I. Holstein bulls will range from 6.2 pounds per minute to 8.1 pounds per minute

PL (Productive Life)

Measured as the total number of additional or fewer productive months that you can expect from a bull’s daughters over their lifetime. Cows receive credit for each month of lactation, with more credit given to the first months around peak production, and less credit given for months further out in lactation. More credit is also given for older cows than for younger animals.

REI (Repro Efficiency Index)

This index is a genetic selection tool developed by PEAK Genetics to support overall improved female fertility. REI combines the most relevant female fertility traits together into one index. This index drives improved reproduction in both cows and heifers, while maintaining a more positive relationship with both production and longevity traits. With REI, dairies can focus on improved production while also improving repro efficiency across the full herd. This makes REI a truly revolutionary index.

What traits are included in REI?

• 25% Daughter Pregnancy Rate (DPR) • 25% Cow Conception Rate (CCR)

• 25% Heifer Conception Rate (HCR) • 25% Early First Calving (EFC)

This means that half of the weight within REI focuses on improved heifer fertility – through HCR and EFC, and half of the weight focuses on improved cow fertility – through DPR and CCR.

RFI Residual Feed Intake

Residual Feed Intake (RFI) is a measure of feed efficiency and is defined as the difference between an animal’s actual feed intake and its expected feed intake based on its size and growth compared to the breed average base. RFI is independent of the level of production. The lower the RFI value, the more efficient the animal is.

RSP (Respiratory Problems)

Respiratory Problems (RSP) represents the expected resistance of an animal’s offspring to calfhood respiratory problems in a herd with average management conditions. PTAs for RSP evaluations are expressed in percentage points of resistance above or below the breed average. Larger, positive values are more favorable, indicating greater resistance.

• Holstein bulls will range from -3.6 to +3.6

• New trait August 2026 for Holsteins and Jerseys.

SCS (Somatic Cell Score)

Somatic Cell Score (SCS) indicates genetic susceptibility for udder health, as revealed through somatic cell count. Animals with PTA SCS <3.0 are expected to transmit favorable udder health, while animals with PTA SCS >3.0 are expected to have daughters with cell counts higher than breed average. The SCS is expressed as the log score of somatic cells per milliliter.

CONFORMATION Traits and Terms

BWC (Body Weight Composite)

An index to measure the overall size and efficiency of a cow, included in NM$ as part of the Feed Saved index. Economic Penalty: Every 1.0 point increase in a bull’s BWC score correlates to an estimated 35-pound increase in their daughters’ mature body weight, raising lifetime feed overhead costs.

The BWC index is comprised of the following linear type traits, in order of weight within the Holstein BWC index: Strength (72%), Dairy Form (-47%), Stature (23%), Rump Width (17%), and Body Depth (8%). Holstein BWC weights are calculated directly from standard deviation impacts (STAs) established by Holstein USA, meaning they do not add up to 100.

The Jersey Breed does not measure Body Depth and has weights of Strength (42%), Stature (42%), Rump Width (35%), and Dairy Form (-21%)

FLC (Foot & Leg Composite Index)

Calculated by Holstein USA, it is an index to describe animals that transmit superior mobility, steeper foot angle, wider rear leg stance with little or no hock-in and slightly straight rear legs side view. It’s comprised of the following linear type traits, in order of weight: Foot & Leg Score (FLS=70%), Stature (ST=-20), Rear Legs Rear View (RLRV=20%), Foot Angle (FA=5%), and Rear Legs Side View (RLSV=5%). Updated April 2025.

HCC (Holstein Conformation Composite)

New July 2026

The Holstein Conformation Composite (HCC) is a selection tool designed to identify animals with the combination of conformation traits most associated with balanced, functionally correct Holstein cattle. The HCC emphasizes intermediate optimum values for key traits that support long-term functionality. It promotes moderate frame size, balanced udders built for longevity and production potential, and sound feet and legs.

Trait Weighting Emphasis:

• Stature 15%

• Feet & Leg Score 7%

• Strength 9%

• Fore Udder Attachment 6%

• Body Depth 3%

• Rear Udder Height 3%

• Dairy Form 4%

• Rear Udder Width 5%

• Rump Angle 6%

• Udder Cleft 8%

• Rump Width 5%

• Udder Depth 5%

• Rear Legs – Side View 5%

• Front Teat Placement 2%

• Rear Legs – Rear View 2%

• Rear Teat Placement 4%

• Foot Angle 8%

• Teat Length 5%

MUI (Modern Udder Index)

MUI was created by PEAK for progressive dairies that need one or both of the following:

• Emphasis on udder selection that promotes moderate sized, long-living, highly productive cows

• A next generation of cows that operate more efficiently in the parlor or robot because they have a more desirable udder cleft, teat length, and teat placement.

The primary objective of MUI is to maintain functional udder traits that impact parlor performance while advancing udder traits that contribute to lifetime production

Values for MUI range from about 0.00 – 15.00. Higher numbers are more favorable for creating cows with modern udders that work more functionally in today’s progressive dairy environments

The following traits are included in MUI:

• Rear Udder Height*

• Fore Udder Attachment*

• Rear Teat Placement***

• Rear Udder Width*

• Udder Depth***

• Front Teat Placement***

• Teat Length***

• Udder Cleft***

* = trait with a capped maximum | *** = two-way trait

PTAT (Predicted Transmitting Ability for Type)

PTA Type predicts the animal’s genetic ability to transmit to the offspring’s final classification or appraisal score in the breed’s program. Published by breed association

TRel: Percent reliability for a sire’s conformation/type proof.

UDC (Udder Composite Index): Calculated by Holstein USA, it’s an index to describe a well-formed, trouble-free udder, capable of holding large volumes of milk. It is comprised of the following linear type traits, in order of weight: Rear Udder Height (RUH) = 23%, Udder Depth (UD) = 20%, Rear Udder Width (RUW) = 19%, Fore Udder (FU) = 16%, Udder Cleft (UC) = 8%, Teat Length (TL) = 5%, Front Teat Placement (FTP) = -4%, Rear Teat Placement (RTP) = -10%, Stature (ST) = -20%.

Genetic Recessives

Carrier Codes

Animals are confirmed carrier of the respective genetic recessive.

• BY: Tested carrier of BLAD (Bovine Leukocyte Adhesion Deficiency)

• CV: Tested carrier CVM (Complex Vertebral Malformation)

• DP: Test carrier of DUMPS (Deficiency of the Uridine Monophosphate Synthase)

• MF: Tested carrier of Mulefoot

• MW: Tested Heterozygous carrier of Early Muscle Weakness

• MW1: Tested Heterozygous carrier of Early Muscle Weakness

• MW2: Tested Homozygous carrier of Early Muscle Weakness

• PO: Observed polled, but not necessarily genetically tested for this trait (polled is a dominant trait)

• PC: Tested heterozygous polled (meaning 50% of offspring are expected to be polled)

• PP: Tested homozygous polled (meaning 100% of offspring are expected to be polled)

• RC: Carrier of recessive red hair color

• B/R: Black/Red hair color

• DR1: Tested heterozygous for the dominant red hair color

• DR2: Tested homozygous for the dominant red hair color

Tested-free Codes

Animals have been tested free of the respective genetic recessive.

• TC: Tested free of the haplotype for cholesterol deficiency

• TD: Tested free of DUMPS

• TE: Tested free of Early Muscle Weakness

• TL: Tested free of BLAD (Bovine Leukocyte Adhesion Deficiency)

• TM: Tested free of Mulefoot

• TP: Tested free of the polled trait (meaning the animal has no polled allele for horns)

• TR: Tested free of red hair color

• TV: Tested free of CVM (Complex Vertebral Malformation)

• TY: Tested free of Brachyspina

Haplotypes

These haplotypes represent specific strands of DNA that cause early embryonic loss, stillbirths, or calf mortality when inherited from both parents (homozygous status). Because affected embryos often die in the early weeks of gestation, these defects usually manifest as poor conception rates, irregular return to heat, or unexplained open cows.

An ‘F’ after each haplotype ensures the animal is tested free of that haplotype. A ‘C’ after each haplotype means that animal is a carrier of that haplotype

• HH1C | HH1F

• HH2C | HH2F

• HH3C | HH3F

• HH4C | HH4F

• HH5C | HH5F

• HH6C |HH6F

HCD0: Non-carrier of the haplotype for cholesterol deficiency, free of HCD

HCD1: HCD carrier, confirmed with pedigree information of the haplotype for cholesterol deficiency

HCD2: Homozygous for HCD, confirmed on both sides of pedigree

HCD3: Suspect carrier, haplotype origin could not be confirmed from pedigree

HCD4: Suspect homozygous, probable carrier and may be homozygous; origin could not be confirmed from pedigree

Codes for Haplotype Associated with Recessive Red (HRR)

ZOETIS INDEXES & TRAITS

The following traits are calculated by Zoetis, and are separate from the health traits from CDCB. Breed average is represented by a value of 100 with higher values signifying improved health and efficiency.

CW$ (Calf Wellness Index)

A selection index calculated by Zoetis that focuses exclusively on calf wellness traits including calf livability, respiratory disease and scours. It estimates the differences in expected lifetime profit associated with the risk of calfhood diseases and early death losses. (Calf Scours = 42%, Calf Respiratory Disease = 25%, Calf Livability = 33%)

DWP$ (Dairy Wellness Profit Index)

Updated April 2026

Calculated and published by Zoetis, it’s a selection index that includes production, reproduction, functional type, longevity, calving, plus Zoetis cow and calf wellness traits, Zoetis fertility traits and Polled test results.

• The Holstein bucket weights break down with approximately 36% on production traits and 64% on health traits. (Quality Production = 43%, Fertility = 12%, Precision Nutrition = 15%, Antibiotic Stewardship = 18%, Animal Welfare = 12%)

• The Jersey bucket weights breakdown with approximately 53% on production traits and 47% on health traits. (Quality Production = 53%, Fertility = 9%, Precision Nutrition = 7%, Antibiotic Stewardship = 17%, Animal Welfare = 13%)

WT$ (Wellness Trait Index)

An index calculated by Zoetis that focuses exclusively on cow wellness traits (Mastitis = 46%, Lameness = 27%, Metritis = 13%, Retained Placenta = 4%, Displaced Abomasum = 6%, Ketosis = 3%, Respiratory Disease = 3%) and estimates potential profit contribution of these wellness traits.

Z_LAME (Zoetis Lameness Index)

The Z_LAME trait is a genetic prediction index developed by Zoetis (via their Clarifide Plus genomic test) that measures a dairy animal’s genetic resistance to lameness. Z_LAME is expressed as a Standard Transmitting Ability (STA), where 100 represents the average disease risk in the baseline population. A score above 100 means the animal has a lower genetic risk of becoming lame compared to the population average.

Z_MAST (Zoetis Mastitis Index)

Z_MAST, is a specific mastitis index developed by Zoetis. When used to compare two animals, higher values indicate the animal with a lower mastitis risk. The productive indexes (i.e., milk, fat, and protein) give an indication regarding the genetic differences in the relative trait yield during a standard lactation of 305 days. Z_MAST is expressed as a Standard Transmitting Ability (STA), where 100 represents the average disease risk in the baseline population. Higher numbers mean the animal has a lower genetic risk of contracting mastitis. For example, a bull or cow with a Z_MAST score of 105 or higher is predicted to sire daughters with better resistance to udder infections than an animal scoring 100 or below.

Cow Wellness Traits

Higher scores mean fewer health incidences.

• Z_MAST (Mastitis): Resistance to udder infections.

• Z_METR (Metritis): Measures resistance to uterine infections after calving.

• Z_LAME (Lameness): Resistance to hoof and leg issues.

• Z_DA (Displaced Abomasum): Measures genetic risk for a twisted stomach.

• Z_REPL (Retained Placenta): Measures the ability to shed the placenta normally after birth.

• Z_KETO (Ketosis): Measures resistance to metabolic ketosis.

• Z_RESP (Respiratory Disease): Measures resistance to pneumonia and upper respiratory infections in adult cows.

• Z_MILK_FEVER (Hypocalcemia): Measures resistance to clinical milk fever during calving.

Calf Wellness Traits

Zoetis scores heifer calves to predict their survival and health before they ever reach the milking string.

• Z_LCALF_RESP (Calf Respiratory): Predicts resistance to calfhood pneumonia.

• Z_CALF_SCOUR (Calf Scours): Predicts resistance to severe diarrhea in early life.

• Z_CALF_LIV (Calf Livability): Predicts overall calf survival from 2 days of age through 10 months.

Fertility Traits

• Z_ABRT (Cow Abortion): Higher values are consistent with animals possessing a lower risk of abortion relative to herdmates with lower values. Higher values are more desirable.

• Z_CYST (Cystic Ovary): Higher values are consistent with animals possessing a lower risk of cystic ovary relative to herdmates with lower values. Higher values are more desirable.

• Z_TWIN (Twinning): Higher values are consistent with animals possessing a lower risk of twinning relative to herdmates with lower values. Higher values are more desirable.

Sustainability and Heat Resilience Traits

• Residual Feed Intake (Z_RFI): Measures the kilograms per day of dry matter consumed that wasn’t accounted for by feed requirements of milk production, metabolic body weight, body weight change, lactation, stage of lactation, and age. A higher value indicates genetic potential for more residual dry matter intake. A lower value is more desirable.

• Milk Methane Intensity (Z_MI): The amount of methane, in carbon dioxide equivalents, a cow is predicted to produce per kilogram of milk in a 305-day lactation. A higher value indicates the genetic potential for more methane per kilogram of milk. A lower value is more desirable.

• Milk Heat Resilience (Z_MR): the change in daily milk production (lbs) per point increase in Temperature-Humidity Index. Higher values are more desirable.

• Fertility Heat Resilience (Z_FR): the change in probability of 1st service conception rate per point increase in Temperature-Humidity Index. Higher values are more desirable.

GENERAL PROOF TERMS

aAa

An independent method for making mating decisions. Learn more HERE.

Beta Casein

A key protein in milk. Studies have shown the A2A2 protein is preferred for its ease of digestibility.

CDCB (Council on Dairy Cattle Breeding)

The CDCB calculates production, health, and efficiency traits and the NM$, CM$, FM$, and GM$ indexes.

DMS (Dairy Mating Service)

An independent method for making mating decisions. 

EFI % (Effective Future Inbreeding Percentage)

An estimate, based on pedigree, of the level of inbreeding that the progeny of a given animal will contribute in the population if mated at random

GFI % (Genomic Future Inbreeding Percentage)

Similar to EFI, an animal’s GFI also predicts the level of inbreeding he/she will contribute in the population if mated at random. Yet, GFI provides a more accurate prediction. It takes into account genomic test results and the actual genes an animal has.

HA-USA (Holstein Association USA)

The world’s largest dairy cattle breeding organization, and the entity that calculates TPI and the conformation trait indexes.

Interbull (Interbull Centre-ICAR)

The Interbull Centre provides genetic information services and applied research for improvement of livestock to a worldwide network and fulfills a mandate as an European Union Reference Centre for the scientific and technical contribution to the harmonization and improvement of the methods of performance testing and genetic evaluation of purebred breeding animals of the bovine species. ICAR is the global provider of independent Guidelines, Standards and Certification for animal identification, recording and evaluation. Responsible for MACE.

Kappa Casein

A key protein in milk. The B variant is often preferred over the A or E variant for cheese making.

MACE (Multiple-Trait Across Country Evaluation)

Denotes that a bull’s proof evaluation includes daughter information from multiple countries.

NAAB (National Association of Animal Breeders)

The NAAB represents 95% of the dairy cattle semen sales in the United States. Responsible for Certified Semen Services CSS that regulates semen and sire health and identification. NAAB provides several genetic programs Cross Reference Program, Issuance of Stud Codes, Issuance of Marketing Codes and the Uniform Coding System for Identifying Semen.

NAAB Code (Uniform NAAB Code)

The system that is the responsibility of the NAAB with a uniform coding system to provide a unique code number for each bull. It includes:

• ID Source of the Semen (organization that produced or processed the semen) Three number prefix

• ID of the breed of the bull Two Letter Breed ID

• A code number identifying each respective bull within each AI organization or marketing company

Example: 011 = Alta | HO = Holstein | 18042 = AltaGoldengate | NAAB Code = 011HO18042

PTA (Predicted Transmitting Ability)

Stands for Predicted Transmitting Ability. It is the estimate of genetic superiority or inferiority for a given trait that an animal is predicted to transmit to its offspring. This value is based on the animal’s own records and the records of known relatives and is equal to half of the Estimated Breeding Value.

RHA (Registered Holstein Ancestry)

The percentage of the animal’s ancestry that can be traced to the origin of US or Canadian Holsteins.