Genetics Guide

Genetic Basics
You will hear many terms that Dexter Breeders use on a daily basis.  Give those breeders grace, as once you understand the terms you will begin doing the same thing.  Here are some terms to help...

Homozygous - having two identical alleles/gene/trait.  The gene/allele/trait received from their Dam and Sire were the same.  We will use "Horned/Polled" as an example:  If the Sire passed on the polled gene, and the dam passed on the polled gene, the calf would be Homozygous Polled and could not have horned calves.

Heterozygous - having two different alleles/gene/trait.  The gene/allele/trait received from their Dam and Sire were different.  We will again use "Horned/Polled" as an example:  If the Dam passed a polled gene to the offspring, but the sire passed a horned gene on, the offspring would have 1 gene for horns and 1 gene for polled.  In this situation polled is dominant (info below on dominant traits), so it would be Heterozygous Polled.

Genotype - a "screenshot" of the Genetic "fingerprint" of the animal.  We use that to Parent Qualify.

Parent Qualification/Verification - is essentially using the Genotype of the Sire and the Dam to determine the offspring is from said parents.

Obligate/Obligation - Obligate status is when you have tested the Sire and Dam, and their Parent Qualified offspring, only has 1 genetic result due to the sire and dams gene/allele/trait.  Example 1 - An A2A2 Cow bred to an A2A2 Bull, the offspring can only be A2A2.  Example 2 - An A1/A1 Cow bred to an A2A2 Bull, the offspring can only be A1/A2.  Obligation can save you big big money.  As of the writing of this page, The Purebred Dexter Cattle Association will utilize this to save you money, at the time of writing this page, the ADCA will allow you to do that on 2 traits only.  Chondrodysplasia and PHA.  You will find some buyers care not about the genetics, while a large swath of the Dexter Breeders will want to know the genetics.  The less you need to spend, the better.

Phenotype - the composition of your Dexter that can be seen/touched/measured often referred to as Conformation of the Dexter, such as hindquarters, head, legs, feet, udder, topline (back) etc.

Dominant - will be, block or override the expression of the recessive allele/gene/trait.  An example of this is Polled, White Dexter Pattern, Black, etc  Polled being dominant means that when a Dexter has 1 Polled Gene and 1 Horned Gene, the animal will be Polled.  

Recessive - can only be expressed if the dominant allele/gene/trait is not inherited. 
An example of this is Horned.  In order for Dexters to be horned, no Polled gene can be present.

* * * * * * * * * * * * * * 

Genotype & Parent Qualification/Verification - It is fairly customary to Genotype and Parent Qualify/Verify your registered Dexter.  This ensures integrity and will help a new Dexter owner have confidence that what they are buying is what you say they are.  Bulls can jump a fence.  Cows can jump a fence.  Both can jump back.  Bull Calves as young as 6 months can be fertile.  An older breeding bull does not prevent pregnancies 100% of the time.  UC Davis, is taking a snapshot, not every single marker/allele.  They do the international standard plus a few extras.  Parent "Verification" is technically "Parent Qualification" as it is possible for Dexters from closely inbred/line bred herds can be hard to distinguish from one another making false confirmations unlikely but possible.  Once you receive a Genotype, it will have a list of markers at the bottom that will make very little sense, that is ok.  It is the Parent Qualification at the top and the Case Number that are what is important.  I recommend always submitting that Case Number to the PDCA or Registry.  The PDCA will post that Case number on the online pedigree.  This will forever more transfer with new owners from then on, so it never gets lost and new owners don't get forced to re genotype the Dexter.  This is just good business and animal husbandry.  To test for this select UC Davis in the link above.

A2 Beta Casein - Test results for A2 Beta Casein are grouped into... A1/A1, A1/A2 and A2/A2.  A2/A2 is considered "the best" by many, but all documentation for benefits, stem from a company promoting A2 Milk.  That is not me saying that I do or do not believe in A1 and A2 milk, just stating I have a healthy skepticism like I do about nearly everything.  I am simply stating the case that you will encounter Dexter Breeders that absolutely believes in A2/A2 being the best.  You will also encounter people that do not agree that A2/A2 is better or even different.  To each their own.  No matter what camp you fall in, we want to teach you how to breed Dexters to get your desired A2 Beta Casein status.  If the bull you use is A2/A2.  On an A1/A1 Cow, the offspring will already be A1/A2.  That is the only result that is possible aka Obligate.  To test, scroll up to the top to the "Milk Panel" from Neogen in the links above.  The milk Panel gives you 4 tests for one price.  (A2 Beta Casein, Kappa Casein, AB Beta Casein and Beta Lactoglobulin)   UC Davis does do 3 of those 4 tests, but they can total up to nearly $123.00, even with the PDCA discount instead of the $16 Neogen Charges (As of May 2025) where you get the 4th milk gene test (AB Beta Casein).

Horned and Polled - the test for Horned and Polled Status, is more than just seeing whether your Dexter has horns or not.  The type of polled, is important for a multitude of reasons.  Horned is a recessive trait.  Polled is a dominant trait.  So if a Dexter has atleast1 polled gene, they are polled.  When testing for polled and horned status, you want to do this test at UC Davis.  With the PDCA discount, UC Davis is the cheapest place to test for Horned & Polled. 
There are only 3 possible results you will get for this test. 
     * H/H means Horned - Animal will have horns unless you dehorn them.
     * Pc/H means Heterozygous Polled - These animals will not have horns, will be polled.
     * Pc/Pc means Homozygous Polled. 
Homozygous Polled will always pass 1 Polled gene on to the offspring. Horned will always pass 1 horned gene on to the offspring.  So when you breed a Homozygous Polled Bull to a Horned Cow, there is no need to test the offspring, as the offspring can be obligated out to be Pc/H.  A Pc/H animal can pass either one to the next generation.  Bottom line, if you want horns on your calves make sure both the sire and dam are horned.  Some people like both horned and polled Dexters. In that case, a Heterozygous Polled bull will be able to throw horned or polled calves (depending on the Dam) or at least carry a horned gene if you want a mix of horned and polled.  If you want every calf to be polled, you want to get yourself a Homozygous Polled Bull.

PHA - PHA also known as (Pulmonary Hypoplasia with Anasarca) in Dexter cattle CAN be a lethal genetic defect characterized by incomplete lung development and severe fluid accumulation, leading to abortion or stillbirth.  It's caused by a recessive gene, meaning calves must inherit two copies to be affected.  PHA is particularly relevant in Dexter cattle due to a specific Dexter variant of the PHA gene.  PHA is personified like the Devil reincarnate - especially on some classless discussion groups on social media platforms like Facebook.  Is PHA something that someday should be eradicated?  Probably!  Should you slaughter every carrier you have?  Absolutely not!  This can be bred away just like any other trait.  When you are testing for PHA, both labs can test it, personally I use UC Davis.  Remember to click PDCA as Primary Affiliate to receive the PDCA discount.  There are only 2 outcomes from the test...
     *A Carrier of PHA is denoted by (PHAD/N or HC)
     *A Non-Carrier of PHA is denoted by (N/N or HN). 
Once you send a copy of your test results to PDCA.Registrar@DextersToday.com, they will put the results online simply "Non-Carrier" or "Carrier".  Once your sire and dam are both on file as Non-Carriers, and the calf is Parentage Qualified, the resulting calf may be marked as a Non-Carrier obligate.  It is important to note, I would absolutely NEVER tell you to butcher, cull or otherwise remove a Dexter from the gene pool that is so limited as it is, over PHA Status.  You shouldn't use a bull that is a Carrier of PHA unless it is of important genetics.  If it is important
genetics, the cow should be a Non-Carrier of PHA.  We have stored Semen from a few PHA carrying bulls that we plan to absolutely use.  50% off the offspring will NOT carry PHA, and we always need beef if they do.  Keep in at no point does it look bad having offspring of a Carrier.  It doesn't have cooties.  Especially if it is tested and is a Non-Carrier.  Otherwise, just make sure your Bull is a Non-Carrier of PHA, then it doesn't matter, just test the offspring.  If your goal is to eradicate PHA in your herd, wonderful, just do not push your beliefs on to others or it becomes propaganda. 
In a Carrier X Non-Carrier mating, 50% will not carry PHA.  50% will.  Feel free to send the Carriers to the Locker, or often people are looking for a milk cow, sell as a pet, etc.  They are not diseased.  They have a genetic trait/fault.  It isn't contagious and the only POTENTIAL problem is breeding two carriers together.  Non-Carriers of PHA, you can retain, in many cases, are spectacular genetics with the one flaw.  I have seen some amazing cows be eliminated from the National Herd over a trait that can be bred around.  We have been breeding for over 21 years, and to this day we still have 4 PHA Carriers and those carriers are some of the best looking Dexters I have ever seen.  One is currently alive at 22 Years of Age.  Forget the propaganda and breed responsibly. 
Breeding Results: 
     * A Non-Carrier Bred to a Non-Carrier will always be a Non-Carrier and can be obligated on your Purebred Dexter Cattle Association Registration Papers. 
     * A Non-Carrier bred to a Carrier, will give you 50% Non-Carriers and 50% Carriers. 
     * A PHA Carrier bred to a PHA Carrier will give you 25% Non-Carriers, yes that is correct, 25% will NOT even carry the gene. 50% will carry the PHA Gene to the offspring.  Again they have use.  The remaining 25% will be aborted sometime between conception and full term.  The issue is that full term Homozygous PHA calves can be dangerous to the cow and in some extreme cases cause death.  That is why we NEVER recommend a Carrier to Carrier mating.  In our tenure in the Dexter Cattle world, we the PHA test was launched it was the biggest purge of genetics in the Dexter Cattle National Herd, that I have ever witnessed.  
 
Beta Lactoglobulin - Beta Lactoglobulin - A major whey protein that has a significant effect on cheese yield. Three outcomes are possible (A/A, A/B and B/B) with this test that is included in the Neogen Milk Panel.  B/B is most favorable; A/B is intermediate; A/A is least favorable.  It's a lipocalin protein with a small size, around 18,400 Da, and is known for its role in various biological processes.  If this is a trait you are going for, don't cull everyone that doesn't have the B/B outcome.  Get a great B/B bull and in a couple generations you will have stock that are B/B.  Too many great animals are sacrificed chasing numbers.

Kappa Casein - Κ-casein, or kappa casein, is a mammalian milk protein involved in several important physiological processes. Chymosin (found in rennet) splits K-casein into an insoluble peptide (para kappa-casein) and water-soluble glycomacropeptide (GMP).  K-Casein serves to maintain the micelles in milk in suspension. The cheese-making protease, rennet, hydrolyzes a single specific peptide bond in the k-casein fraction of milk resulting in destabilization of the milk micelles and coagulation.  A non-whey protein associated with increased protein yield and percentage.  Six outcomes (B/B, A/B, B/E, A/A, A/E, and E/E) happen in this test done at Neogen as part of their Milk Panel.  B/B is most favorable; A/B and B/E are intermediate; A/A, A/E and E/E are least favorable. The E/E variant of Kappa Casein does not clot well and therefore is not suitable for cheese making.

AB Beta Casein - A protein associated with improved cheese making. AB beta-casein refers to a genetic variant of the beta-casein protein found in milk, where the individual carries both the A1 and A2 alleles. A1 and A2 beta-casein are two different forms of the same protein, differing by a single amino acid at position 67 of the protein chain. This single amino acid difference can affect how easily the milk is digested and whether it triggers sensitivities in some individuals. Three outcomes are possible in this test.  (B/B, A/B, and A/A).  B/B is most favorable; A/B is intermediate; A/A is least favorable.  

MC1R (Red & Black) - MC1R also known as Melanocortin Receptor.  I am going to try and stay out of the weeds with this one and keep it simple for everyone to understand.  There are three types (Black ED, Wild Red E+, Recessive Red e)  When testing for Red, you can use either lab, and uniquely, this particular test is higher or lower priced based on what else you test at said lab.  If you need help deciding where to test to save the most money, and you aren't sure after reading all of this,  feel free to reach out to the PDCA Registrar at PDCA.Registrar@DextersToday.com or Pedigree & Genetics Committee Chair or us!  GrandmasDexters@gmail.com.  With this test, there is Six possible outcomes.  ED/ED, ED/E+, ED/e, E+/E+, E+/e, e/e. 
Let's get into some meanings...
     * ED/ED - Homozygous Black, will be black in appearance unless TYRP1/Dun is Homozygous
     * E+/E+ - Homozygous Wild Red, will be Red in appearance.
     * e/e - Homozygous Recessive Red, will be Red in appearance.
     * ED/E+ - Heterozygous Black, Heterozygous Wild Red, will be black in appearance unless TYRP1/Dun is Homozygous.
     * ED/e - Heterozygous Black, Heterozygous Recessive Red, will be black in appearance unless TYRP1/Dun is Homozygous.
     * E+/e - Often described as "Split Red", is Heterozygous Wild Red, Heterozygous Recessive Red, will be Red in appearance.
When it comes to breeding for a color, it works like any other gene/allele or trait.  The sire carries 2 options at MC1R and the Dam does as well.  Each will give 1 of their markers to their offspring.  So when you have Homozygous options, the offspring will obligate out (once the offspring is Parent Qualified).  Example:  If I have a E+/E+ Red Bull and I breed it to an e/e Red Cow.  The offspring will be Red 100% of the time but her MC1R will be E+/e as she would receive E+ from the sire and e from the Dam.  Very simple once you get the hang of genes.

Dun (TYRP1 aka Dexter Dun) - Dun is very interesting.  All we know about the Dun gene is thanks to John Potter of Spruce Grove Farm, Carol Davidson of Hiyu Herd, and Patti Adams from Wakarusa Ridge Ranch picking up the mantle of Carol Davidson's research and work, after her passing discovering Dexters in fact have a second gene for Dun.  Dun is a beautiful color than can come in any shade between blonde all the way to a deep chestnut and everything in between.  As of June 2025, I can only report about the TYRP1 version of Dun.  The test performed at UC Davis will have 3 outcomes. (B/B, B/b, b/b).
     * B/B - Homozygous for Non-Dun - Doesn't Carry Dun, Is not Dun, will not produce a Dun Calf.
     * B/b - Heterozygous for Dun - Carries Dun, is not Dun in color, can produce a Dun Calf if the other parent also carriers or is Dun.
     * b/b - Homozygous for Dun - Dexter will be Dun (unless Red dominates Dun) and will throw at least a gene for Dun to every single calf.  Can be Red or Dun in Color depending on what the MC1R test is.  (or the White test in the case of White Dexters)  This is such an interesting topic.  Down below we will explain how TYRP1 (Dun), MC1R (Black & Red, and (WDP) White work together.  At Grandma's Dexter Farm, we love having Red Dexters that are also Homozygous for Dun.  They are always Red, and will breed as though they are Red, BUT, they will also breed as they are Duns.  Examples of this.  SGF LPFK Antares, a very well known AI Bull and FF Freedom's Harvest Moon are both (e/e b/b)  They are Homozygous Recessive Red - and - Homozygous Dun.  If you bred them to a Red cow, you will get a Red offspring 100% of the time.  If you breed them to a Dun Cow, that does not carry Red (ED/ED) the offspring 100% of the time will be Dun!  A Dun bred to Dun will always produce a Dun, unless both carry Red and Red is expressed.

White Dexter Pattern (WDP) -  The white color in our Dexters is created through a variant in chromosomal sequencing. The variant is dominant, meaning if the animal has at least one copy of the White Dexter Pattern (WDP) gene, the animal will show white (sometimes in varying degrees).  White breeds similar to polled, the Dexter either has it or it doesn't and does not "Carry the gene" on.  Texas A&M is the only place currently that does the WDP test.  So by default that is where you will want to go to get that testing done.  That is the only testing I do at TAMU.  When testing you have 3 outcomes.  N/N, W/W, W/N.  Let's dig into what that means. 
     * N/N - Any Dexter that has no White Dexter Pattern, will be N/N.  This means whatever they are at MC1R and TYRP1 is what they will be in coat color.
     * W/N - This result means your White Dexter is a White with some color of tips/pattern.  This can be a varying degree.  When breeding, 50% of the offspring will receive a WDP Gene, 50% will not.  This is how you get Red Black and Dun offspring out of white parents.
     * W/W - Your Dexter is Homozygous White.  Since it carries 2 White Genes, every single calf will receive one, meaning this particular Dexter will throw a White offspring 100% of the time regardless of the color of the opposite parent.
Tip Color - The Tip/Pattern Color will be exactly like it would have been, had no White gene been introduced.  Example:  W/W, E+/E+ b/b Dexter would be White, have Red Tips and would breed as if it was White, Red and Dun at the same time.

Color wrap up -  Genetically there are so many genetic combinations of color.  Color can be a fun add on to your Dexter Breeding Program * However * Do not let the color be the main objective that you breed for.  Often in the past during the "Red Craze" sub par animals were used and bred in mass, just to create more Reds, unfortunately many times if you don't look at the WHOLE picture, you can wind up letting conformation, legs and feet, udder, head, temperament, etc. can all be pushed aside and that is when disaster can happen.  It is a fine goal to breed for Black, Red, Dun or White.  Just make sure the quality is not lost chasing color or for that matter, even the numbers from the tests above and below.

Chondrodysplasia (BD1) - This one is a sensitive topic.  There is a tremendous amount of propaganda regarding Chondro (Pronounced Con Dro) on the internet.  When many people look at old Dexter Cattle books, what do they see? Chondro+ cows.  Chondro was such a pronounced part of the breed, at one time people hid non-carriers "Behind the Barn" out of embarrassment.  Chondro is, has been and always will be part of the breed.  It is part of what made Dexter Cattle unique and honestly the national herd has changed immensely by those trying to eradicate it.  In 2003 RFD-TV and Maureen McCready from Fan-C-Dexters recorded a show on Dexter Cattle and had it not been for Chondro+ Dexters my Grandma may have never gotten into Dexters.  Her 1st, 2nd, 3rd, 6th Dexters were Chondro+.  That is what drew her and many many others to the breed.  Many "Miniature Breeds of Cattle" have used Dexters to breed in the Chondro gene, to help lower size and give them that beefy look that comes from many Chondro+ Dexters, we know this because BD1 is a Dexter Variant.  While we are on that subject BD2 and BDZ are not necessary to test in Dexter Cattle across North America.  Simultaneously, we are trying to eradicate Chondro, mostly in service to the almighty dollar.  While a few people run their mouth about shortened lives, here is something to think about.  If they were other breeds of cattle, they would NEVER live as long as a Chondro+.  Chondro+'s live longer than Traditional Cattle.  Non-Carriers of Chondro live even longer.  Saying it is not fair for a cow to have a 15 year life is crazy when most are beef by 8 to 12 years of age, many Dairy cattle are retired and beefed by 8 or 9.  Do Non-Chondro's live longer than Chondro+'s?  Sure!  If you don't wish to breed Chondro+ Dexters, I am happy for you.  If you do wish to breed Chondro+ Dexters, I am happy for you.  If you push your beliefs on others, you should be ashamed of yourself.  When testing for Chondro, I would recommend UC Davis.  They are cheaper (Most of the time) than Neogen, especially when you click PDCA Affiliated for the discount.  You will get 2 possible outcomes N/N or N/BD1. 
     * N/N or CHOF or HN - means Non-Carrier of Chondro.  Breeding 2 Non-Carriers together will always obligate out to a Non-Carrier.  In order to express the Chondro Gene, you must have one or the other parent capable of passing the gene on.
     * N/BD1 or CHOC or HC - means they are a Carrier of Chondro aka Chondro+.  Breeding a Non-Carrier bull with a Carrier cow, will result in 50% of the offspring being Non-Chondro and 50% being Chondro+.  We do not recommend breeding 2 Carriers together, however, if you do, 25% of the offspring will be a Non-Carrier of Chondro, 50% of the offspring will be a Carrier of Chondro, and the other 25% will be aborted between conception and 7 months in
womb, with many at the 60 day mark.  Many people report that in actuality it is no where near 25% of the time.  Keep in mind, in many cases it is 25%, however, if they lose the calf at 2, 4, 8 weeks, it just looks like she slipped (loses/aborts) the calf, gets re bred and then it is a new roll of the dice.  I use that language because the propaganda arm of Dexters are constantly posting pictures about Dead calves as if your pasture will be littered all over the pasture.  Again, most of the time, they will lose that calf in the first 60 days of pregnancy and it looks like they just took a little longer to settle than the other cows.    At the same time - I do not advocate for you to breed 2 carriers together.  Not because of a holocaust of calves in your pasture some claim but it feeds into the narrative of those trying to change the breed.  Dexters are an amazing breed of cattle and you should not be brow beat into locking arms and changing the breed because a handful of people have ulterior motives on what a "Dexter" should be.  Breed the type you like.  Breed responsibly.  Hopefully some day the Associations will get a grip on the tyrants that are trying to make the original intent of the breed - a dark time in the Dexter Breed for the history books. 

Tenderness! (TEND) - Let's talk Tenderness!  Genetic potential for beef tenderness based on Warner-Bratzler Shear Force. Trait is scored in the Igenity Beef and the Tenderness/Leptin Test.  This is currently an "all-breed'' test with the breeds not singled out from one another.  Personally, I believe there are Tenderness Genes specific to a Dexter that they are not using for the test, which is fine.  I have personally seen 3 and 4 Dexters be more tender than an 8 or above "Non-Dexter".  The scoring is a 1 through 10, the higher the number the more tender the beef.  This isn't an arbitrary test, meaning, if you do the "Tenderness/Leptin Panel which we will talk about next, you will be able to figure out exactly what genes your Dexter carries that makes up that score.  Calpain316, Calpain4751, CAST and Leptin make up the score based on which genes they do and do not carry for each one of those traits.  So think of Tenderness Score as an "I don't care how it got there, just want to know the score and go from there".  People that want to know how it got there, will want the Tenderness/Leptin Panel.  Sidenote:  You may encounter some people in Dexter Cattle that do not believe in this test, which is fine if they do not believe in testing.  Uninformed people will bash this test, while not only promoting but forcing you to do other tests just to be part of their cult, I mean social media page.  It's a good idea to always be aware of the propaganda.

Tenderness - Calpain316 - This gene currently, is slightly elusive in the Dexter Breed.  It is there, just harder to find.  Calpain works to break down muscle fiber and is a predictor of tenderness. Alleles each explain from 0.4% to 2% of tenderness variation across breeds. When you run the Tenderness/Leptin Test from Neogen, there are 3 possible outcomes for this test.  CC, CG, GG.  The ‘C’ allele is associated with more tender meat.  So to take advantage of this gene, a CC would be what you would shoot for.  That being said it isn't about just one gene.

Tenderness - Calpain4751 - This gene is easier to find and makes a more significant impact to the overall score.  Three potential outcomes from this test are CC, CT, TT.  The ‘C’ allele is associated with more tender meat.  So again, CC can be the goal especially of a bull, but it is just a part of the whole package.  Don't sacrifice a quality animal for an arbitrary number.

Tenderness CAST - Calpastatin is an inhibitor of Calpain. When testing through Neogen using the Tenderness/Leptin test, three outcomes are possible.  CC, CG, GG.  The ‘C’ allele is associated with more tender meat.

Leptin - Leptin is a fat-metabolism hormone with a mild effect on fat deposition. So your result outcomes are TT, CT, CC.  Leaner cattle carry allele C and more marbled cattle carry the allele T.  

Igenity Maternal Index (IMI) - This index is highly maternal and designed to select replacement heifers for fertility, longevity and higher weaned calf weight. It is a tool developed for producers who sell calves at weaning or after a short backgrounding period. 

Igenity Production Index (IPI) - The Igenity Production Index is well balanced for maternal, production and carcass progeny traits. It is designed for producers who raise their own heifers and want broad improvement across multiple traits. 

Igenity Terminal Index (ITI) - The Igenity Terminal index is specialized to identify animals with superior carcass performance. It places the highest emphasis on hot carcass weight, followed by marbling and rib eye area. There is, however, a negative emphasis placed on residual feed intake and fat thickness to control feed costs.

Birthweight (BW) - Higher scores equate to higher birthweight potential. Heavy calves can cause calving difficulty but also have more growth potential. (CED or CEM in selection indexes are preferred over BW alone).  Why is this important?  When you are breeding first calf heifers, you want to stick to a 1 or 2 to avoid calving issues.  Most Dexter Breeders wish to stay 3/4 or under unless your Dexters are large framed.  Others stick to 1's or 2's to avoid calving issues with calves being too large.

Calving Ease Direct (CED) - Greater probability a calf will be born unassisted out of a first-calf heifer, including birth weight and shape of the calf. A higher value is greater calving ease.

Calving Ease Maternal (CEM) - Includes all genetic factors that impact a first-calf heifer’s ability to calve unassisted, such as pelvic area and her genetics for birth weight. Higher value is more calving ease.

Heifer Pregnancy Rate (HPR) - A heifer’s potential to conceive during breeding season, relative to other heifers. A higher value is desired.  This can be used to select which heifers to keep back as replacement heifers.

MILK - Pounds of calf weaning weight due to dam’s milk production. Optimize “milk” to the forage environment.

Stayability (STAY) - The chance a heifer will remain in the herd as a productive cow until at least six years of age. A higher value is desired.

Hot Carcass Weight (HCW) - Unchilled weight of a beef carcass. The higher the HCW, the greater the dressing percentage.

Docility (DOC) - Genetic potential to be calm or have calm offspring. Higher scores indicate a higher probability of acceptable disposition.  This is data that can also be used to select breeding stock.  There is a nature vs nurture debate on this.  Let me attempt to clear the muddy water, If you have a 2 and a 7.  You care for them the same, you work them the same, the 7 will be more docile.  This does not judge nurture.  So if you take that 2 and halter break her and train her to be milked and give her treats and love daily, she may be tamer than the 7.  This is simply a nature test.

Weaning Weight (WW) - Difference in average 205-day weight. The higher the number, the greater the weaning weight of calves.

Average Daily Gain (ADG) - Based on pounds of gain per day. The Igenity score for Average Daily Gain (ADG) identifies genetic potential for post-weaning growth.

Yearling Weight (YW) - Difference in average 365-day weight. The higher the number, the greater the yearling weight.

Residual Feed Intake (RFI) - This is an indicator of feed efficiency. It is the difference in animals’ daily consumption of feed to achieve the same level of daily gain. Lower RFI indicates greater feed efficiency.

Scrotal Circumference (SC) - Difference in scrotal size as an indication of fertility in replacement females. A higher score equates to higher scrotal size.

Marbling (MARB) - USDA marbling score at a similar end-point. The higher the marbling, the higher the USDA quality grade.

Ribeye Area (REA) - Ribeye area as measured on a carcass. REA estimates muscling in a beef carcass in square inches of ribeye at the 12th rib. Larger REA progeny have more muscle and higher percentage of retail product.

FAT - Backfat as measured on a carcass. Fat thickness is scored as depth of fat in inches over the ribeye muscle at the 12th rib. Higher fat thickness scores equate to lower lean yield.