Let’s face it; sometimes understanding bull proofs can be like reading a document in a foreign language. With all the letters, numbers and acronyms on a proof sheet, it is enough to confuse even the most passionate dairy breeder. With the Bullvine has developed this cheat sheet to help you understand North American Genetic Evaluations easier.
Most genetic selection indexes are set by national organizations or breed associations. Genetic indexes help dairy producers focus on a total approach to genetic improvement, rather than limiting progress by single trait selection. It is important to remember that every farm is unique, with different management environments and situations and goals. With that in mind, it is important to understand what traits are included in each industry standard index. When you know what’s involved, you can more efficiently evaluate if the index indeed matches your farm’s goals.
TPI® = Total Performance Index
The primary selection index recommended by the Holstein Association USA is the Total Performance Index. TPI® is not necessarily aimed at breeding individual cows, but rather to advance the entire genetic pool. TPI® it consists of the following emphasis:
- PRODUCTION TRAITS = 46%
- 21% Pounds of protein
- 17% Pounds of fat
- 8% Feed efficiency
- HEALTH TRAITS = 28%
- 13% Fertility index
- -5% Somatic cell score
- 4% Productive life
- 3% Cow livability
- 2% Daughter calving ease
- 1% Daughter stillbirth
- TYPE TRAITS = 26%
- 11% Udder composite
- 8% PTA type
- 6% Foot & leg composite
- -1% Dairy form
LPI = Lifetime Profit Index
The Lifetime Profit Index (LPI) is the primary selection tool used within each dairy breed in Canada. The main goal of LPI in each breed is to define the combination of traits for which genetic progress is desired and the relative importance of each trait for achieving the overall breed improvement goals. The current Holstein LPI formula places the following emphasis on its three major components:
- 51% Production
- 34% Durability
- 15% Health & Fertility
Read more: (Everything You Need To Know About TPI and LPI)
NM$ = Net Merit Dollars
NM$ is a genetic index value calculated by the Council on Dairy Cattle Breeding (CDCB which estimates lifetime profitability of an animal; defined as the difference in expected lifetime profit of an animal, compared with the average genetic merit of cows within the breed born in the year of the genetic base. Like the TPI®, NM$ combines several production, type and health traits with weightings placed on their economic importance and the goals of the index. Trait weightings are updated approximately every five years and are currently:
- PRODUCTION TRAITS = 43%
- 24% Pounds of fat
- 18% Pounds of protein
- -1% Pounds of milk
- HEALTH TRAITS = 41%
- 13% Productive life
- 7% Cow livability
- 7% Daughter pregnancy rate
- -6% Somatic cell score
- 5% Calving ability
- 2% Cow conception rate
- 1% Heifer conception rate
- TYPE TRAITS = 16%
- 7% Udder composite
- 6% Body weight composite
- 3% Foot & leg composite
CM$ = Cheese Merit Dollars
Lifetime Cheese Merit $ was designed for producers who sell milk in a cheese market. Protein has more value in the cheese market than it does in the standard component pricing market. Milk receives a negative economic weight in the Cheese Merit index. Calculated by the current CM$ index was adjusted in April 2017 and the following trait weights are:
- PRODUCTION = 50%
- 22% Pounds of protein
- 20% Pounds of fat
- -8% Pounds of milk
- HEALTH = 37%
- 12% Productive life
- -7% Somatic cell score
- 6% Cow livability
- 6% Daughter pregnancy rate
- 4% Calving ability
- 1% Cow conception rate
- 1% Heifer conception rate
- TYPE TRAITS = 13%
- 6% Udder
- 5% Body weight composite
- 2% Foot & leg
Recently Zoetis introduced new health and wellness trait indexes with their Clarifide Plus Testing (Read more: The Complete Guide to Understanding Zoetis’ New Wellness Traits – CLARIFIDE® Plus). The composite indexes that were introduced are:
- Wellness Trait Index™ (WT$™)
WT$ focuses exclusively on six wellness traits (mastitis, lameness, metritis, retained placenta, displaced abomasum, and ketosis) and includes an economic value for Polled test results.
- Wellness Profit Index™ (DWP$™)
DWP$ is a multi-trait selection index which includes production, fertility, type, longevity and the wellness traits, including Polled test results.
General Proof Terms
- CDCB: Council on Dairy Cattle Breeding
CDCB calculates production and health trait information for all breeds in the USA
- CDN: Canadian Dairy Networks, calculates the genetic evaluations for all the major Dairy Breeds in Canada.
- NAAB: The National Association of Animal Breeders (NAAB) maintains a database of marketing code numbers assigned to all bulls who enter AI. The NAAB Uniform Code conveys three useful pieces of information:
- A one to three digit numeric code indicating where the semen was processed (AI Unit)
- A two letter alpha code designating the breed of the bull (HO = Holstein)
- A one to five digit numeric code identifying the bull which produced the semen.
- MACE: Multiple-trait across country evaluation
MACE combines information from each country using all known relationships between animals, both within and across populations.
- PTA: Predicted transmitting ability
Predicted Transmitting Ability is the predicted difference between a parent animal’s offspring from average, due to the genes transmitted from that parent. Each PTA is given in the units used to measure the trait. The PTA for milk is reported in pounds or kilograms, the PTA for productive life is reported in months.
- EFI: Effective future inbreeding
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 (Read more: The Truth about Inbreeding)
- GFI: Genomic future inbreeding
Similar to EFI, an animal’s GFI value predicts the level of inbreeding he/she will contribute to 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.
- aAa: aAa analysis defines a cow’s structure under six categories. It relies purely on the physical attributes of the animal; no genetic merit is taken into consideration. The analysis aims to strike a balance between enough “roundness” to live and enough “sharpness” to milk high yields.
- DMS: The Dairy Mating Service (DMS®) program is designed to be an efficient, totally independent system to help dairymen breed higher-producing and longer-living cattle.
Similar to aAa DMS is a visual analysis of a dairy cow. Each cow is visually analyzed to determine strengths and weaknesses which may be passed on to offspring. When available it also considers each animal’s ancestry to find trends and patterns in the transmission of various genetic traits.
Production Trait Terms
- PTAM: PTA for milk production in pounds, reflecting the expected milk production of future mature daughters
- PTAP: PTA for protein production in pounds, comparing the expected production of future mature
- PTAP%: Indicates the genetic variance of a bull’s PTA for transmitting protein as being positive or negative
- PTAF: PTA for butterfat in pounds, reflecting the expected butterfat production of future mature daughters.
- PTAF%: Indicates the genetic variance of a bull’s PTA for transmitting fat as being positive or negative.
- PRel: the percent reliability of a sire’s production proof
- Daughter ME Averages: This number tells you what daughters of a bull are actually averaging for a given trait, in this case, what they average for milk production. These values are based on twice a day milking, 305-day lactation, on a Mature Equivalent (ME) basis. If a bull has an official MACE evaluation, the daughter production averages will be based on the bull’s domestic U.S. evaluation.
- Management Group ME Averages: This number allows you to contrast how daughters of a bull perform compared to herdmates of the same age, so you can evaluate whether they are, on average, superior or inferior to herdmates. Herdmates of the same age as Planet’s daughters are averaging 27,487 pounds of milk; on average, Planet daughters are producing 2,289 pounds of milk more in a 305-day lactation than their herdmates of the same age, on an ME basis.
- Management Group ME Averages: Herdmates of the same age as Planet’s daughters are averaging 1,011 pounds of fat; on average, Planet daughters are producing 75 pounds of fat more in a 305-day lactation than their herdmates of the same age, on an ME basis.
- Beta-Casein: Beta-Casein is a major casein protein making up 30% of the total milk protein. Studies have shown health benefits for diseases such as type 1 diabetes, IHD, schizophrenia and autism. (Read more: 12 Things You Need to Know About A2 Milk)
- A2A2 – Most ideal test result
- A1A2 – Median result – produces equal amounts of A1 and A2
- A1A1 – Least ideal test result
- Kappa-Casein (cheese production)
There are many forms of Kappa-Casein A, B and E associated with milk protein and quality. Variants are related to the processing of cheese. Studies show yield for cheese production is higher with BB milk versus AA milk.
- BB – Preferred result for cheese production
- AB + BE – Intermediate result for cheese production
- AA + AE – Least favorable result for cheese production
Health & Fertility Trait Terms
- PL: Productive Life
Productive life (PL) gives a measure of the amount of time a cow stays in the herd as a “productive” animal and represents how many months of additional (or fewer, if a negative number) lifetime you can expect from a bull’s daughters. Cows receive credit for each month of lactation, and the amount of credit corresponds to the shape of the lactation curve. The most credit is given to the months at the peak of lactation, and credit diminishes as the cow moves to the end of her lactation. First, lactations are given less credit than later lactations, in proportion to the difference in average production. PTAs for PL generally range from -7.0 to +7.0, with higher numbers being preferred. (Read more: Breeding for Longevity: Don’t believe the hype – It’s more than just high type)
- LIV: Cow livability)
Measure of a cow’s ability to remain alive while in the milking herd. (Read more: Cow Livability: Breeding for Cows That Stay in the Herd)
- SCS: Somatic cell score
The PTA for SCS is used to improve mastitis resistance. Bulls with low PTA for SCS (less than 3.0) are expected to have daughters with lower mastitis than bulls with high PTA for SCS (greater than 3.5). Health management has the biggest effect on SCS, but just like some people inherit a higher chance of getting ear infections, cows can inherit traits which cause higher Next to traits like milk or protein production, SCS has a low heritability.
- DPR: Daughter pregnancy rate
Daughter Pregnancy Rate is defined as the percentage of non-pregnant cows that become pregnant during each 21-day period. DPR takes into account how quickly cows come back into heat after calving and conception rate when bred. 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. DPR PTA values typically range from +3.0 to -3.0, with higher values being preferable. Each increase of 1% in PTA DPR equals a decrease of 4 days in PTA days open. (Read more: Does Your Breeding Program Save You Labor?)
- HCR: Heifer conception rate
A virgin heifer’s ability to conceive – defined as the percentage of inseminated heifers that become pregnant at each service. 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. Services are only included if the heifer is at least 12 months old and less than 2.2 years.
- CCR: Cow conception rate
A lactating cow’s ability to conceive – defined as the percentage of inseminated cows that become pregnant at each service. 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. CCR simply looks at the daughter’s ability to conceive when inseminated.
- SCR: Sire Fertility
Service Sire Conception Rate (SCR) is the difference of conception rate of sire expressed as a percent comparison. SCR is based on conception rate rather than non-return rate. SCR utilizes multiple services per lactation (up to 7), rather than first service only. A SCR of 1.2 means the bull is 1.2% above average.
- HRel: the reliability percentage for a sire’s health traits
- Body Condition Score (BCS)
BCS is sourced from the Canadian Dairy Network (CDN). BCS reflects the animal’s energy balance status in which research has clearly shown an association with improved female fertility, longevity and disease resistance. BSC evaluations are expressed as relative breeding values with 100 being average. The scale of expression generally varies from 85 for bulls with daughters that generally have very low scores for body condition to 115 or higher for bulls with daughters that have high scores. Bulls rated over 100 are more desired.
- Mastitis Resistance (MR)
MR is sourced from the CDN. MR combines both clinical and sub-clinical mastitis into a single genetic selection index. The MR index puts equal weighting on the three areas of clinical mastitis in first lactation cows, clinical mastitis in later lactations and somatic cell score across the first three lactations. MR is expressed as a relative breeding value where 100 is average.
- Milking Speed and Milking Temperament
Data points come from the CDN. Milking Speed is evaluated in terms of the percentage of first lactation daughters evaluated as average or fast. Milking Temperament can be defined as milking behavior. Milking Temperament is expressed in terms of the expected percentage of future daughters evaluated as average, calm or very calm during their first lactation. A bull with a score of 100 for both traits indicates average.
Calving Trait Terms
- SCE: Sire calving ease
The percentage of bull’s calves born that are considered difficult in first lactation animals. Difficult births include those coded as a score of 3, 4 or 5 on a scale of 1-5, with a 1 classified as “no problem”). The percent difficult births among first-calf Holstein cows is approximately 8 percent. In general, bulls with an SCE of 8% or less are considered “calving ease” bulls that are fine to use on heifers and smaller cows. Bulls with a high SCE percentage should be used with caution on heifers and smaller cows, as they have a higher percent chance of siring larger calves that may pose more of a problem at delivery.
- DCE: Daughter calving ease
Like Sire Calving Ease (SCE), Daughter Calving Ease (DCE) is a measurement of the tendency of calves from a particular animal to be born more or less easily. DCE measures the ability of a particular cow (a daughter of a bull) to calve easily; daughters of bull’s with high DCE numbers would be expected to have a more difficult time giving birth than daughters of bulls with lower DCE numbers. DCE is evaluated on the same scale as SCE.
- SSB: Sire stillbirth
The percentage of a bull’s offspring that are born dead to first lactation animals.
- DSB: Daughter stillbirth
Measures the ability of a particular cow (daughter) to produce live calves. Stillbirth is expressed as percent stillbirths, where stillborn calves are those scored as dead at birth or born alive but died within 48 hours of birth.
Type / Conformation Trait Terms
In the US 18 linear traits are expressed on a scale of Standard Transmitting Abilities (STAs) deviations, typically between -4.0 and +4.0. For example, Rear, legs side view – an extreme negative value – a cow will have very posty, straight legs, while a extreme positive value will have sickle, curved rear legs. In Canada there are 22 descriptive traits appraised using a 9-point linear
scale, with resulting breeding values typically between -20 to +20. A rule of thumb we use to understand CDN proofs is divide by 5 and you will have their approx US scale for that trait.
- PTAT: Predicted transmitting for type
PTA Type is an estimate of the genetic superiority for conformation that a bull will transmit to its offspring. This is directly correlated with the final score of the bull’s daughters, not the linear traits.
- UDC: Udder composite index
Udder Composite is an index based on ability for udder improvement. Udder composite includes six linear traits, and the weighting for each trait’s contribution to higher udder scores. The traits and their weightings are:
- 19% Rear udder height
- 17% Udder depth
- -17% Stature
- 6% Rear udder width
- 13% Fore udder attachment
- 7% Udder Cleft
- 4% Rear teat optimum
- 4% Teat length optimum
- 3% Front teat placement
- FLC: Foot and leg composite index
FLC is a measure of a bull’s ability for foot and leg improvement. Weights for the four traits in the composite are:
- 58% foot and leg classification score
- 18% rear legs rear view
- -17% stature
- 8% foot angle
- Mammary System (Canada)
- Udder Floor 4%
- Udder Depth 12%
- Udder Texture 14%
- Median Suspensory 14%
- Fore Attachment 18%
- Front Teat Placement 5%
- Rear Attachment Height 12%
- Rear Attachment Width 10%
- Rear Teat Placement 7%
- Teat Length 4%
- Feet and Legs (Canada)
- Foot Angle 9%
- Heel Depth 22%
- Bone Quality 10%
- Rear Leg Side View 14%
- Rear Legs-Rear View 31%
- Thurl Placement 14%
- Dairy Strength (Canada)
- Stature 12%
- Height At Front End 3%
- Chest Width 23%
- Body Depth 17%
- Angularity 28%
- Rump (Canada)
- Rump Angle 23%
- Pin Width 21%
- Loin Strength 32%
- Thurl Placement 24%
- TRel = the percent reliability for a sire’s conformation/type proof
- PO: observed polled
- PC: genomic tested as heterozygous polled; means 50% of offspring are expected to be observed as polled
- PP: genomic tested as homozygous polled; means that 100% of offspring are expected to be observed as polled
- COAT COLOR
- RC: carries the recessive gene for red coat color
- DR: carries a dominant gene for red coat color
- RECESSIVES & HAPLOTYPES
These codes, or symbols representing the code, will only show up on a proof sheet if an animal is a carrier or test positive for one of the following. The acronyms denoting that an animal is tested free of a recessive will only show up on its pedigree.
- BY: Brachyspina
- TY: Tested free of brachyspina
- BL: BLADS, or Bovine leukocyte adhesion deficiency
- TL: Tested free of BLADS
- CV: CVM or Complex vertebral malformation
- TV: Tested free of CVM
- DP: DUMPS, or Deficiency of the uridine monophosphate synthase
- TD: Tested free of DUMPS
- MF: Mulefoot
- TM: Tested free of mulefoot
- HH1, HH2, HH3, HH4, HH5: Holstein haplotypes that negatively affect fertility
- HCD: Holstein haplotype for cholesterol deficiency
The Bullvine Bottom Line
The letters, numbers, and acronyms on a proof sheet can be complicated. We hope that this cheat sheet will help you better understand them the next time you go to make your mating decisions. It is important to remember not to try and correct everything with each mating, but instead pick the 2 to 3 traits that your animals need to be corrected most.