Understanding Wagyu

Wagyu genetics have a complex and long history beginning with their origins in Japan. Wagyu pedigree reading and genetics can be difficult and time consuming. Fortunately, Wagyu specific Estimated Breeding Values (EBVs) are readily available and increasing in reliability. EBVs assign numerical values to a wide variety of traits making it easy to identify the strengths, weaknesses, and rankings of animals. This creates easier decision making for current breeders and less daunting decision making for those looking to enter the Wagyu industry. EBVs, along with pedigrees, prefectural analysis, and recessive testing represent a wealth of information available to all breeders.

There is an ever-increasing wealth of performance and carcass data available to breeders. It is important to consider several factors when reviewing raw data. First, what is the story behind the data? What environment were animals raised in? We cannot be comparing apples to oranges; this is why contemporary grouping and software data analysis (i.e. Breedplan) are extremely important because they attempt to take into account the influence of the environment. What was the environment; were all animals fed the same ration, were all animals on feed for the same number of days? Remember data of animals/sires from different herds cannot be directly compared because of differences in environment. EBVs and EPDs are the only way to accurately compare animals raised in different environments.

Wagyu Breedplan

Run by the Australian Wagyu Association (the largest Wagyu registry outside Japan), Breedplan has published EBVs for Fullblood and Purebred Wagyu since 2015. This is the largest Wagyu EBV/EPD database outside of Japan. Wagyu Breedplan’s analysis includes more than 101,000 dams and 11,700 sires. Breedplan data includes more than 31,500 birth weights, 33,500 weaning (200 Day) weights, 28,000 400 Day weights, Fullblood carcass data of 9,500 carcass weights, 5,700 carcass EMAs, and a total of 9,100 carcass AUS-Meat marble scores, camera marbling percent and camera fineness index measures.

Wagyu Breedplan is backed by world leading genetic analysis software from Agricultural Business Research Institute (ABRI) and Animal Genetics and Breeding Unit (AGBU) geneticists. This has led to the utilization of industry leading single-step genomic analysis to produce Genomic Enhanced EBVs (GEBVs). Commonly referred to as “Genomics”, GEBVs produce increased accuracy through the analysis of 50K SNP DNA data, along with tradition pedigree and performance data. Genomics or GEBVs allow for earlier and more accurate selection and identification of elite cattle.

Wagyu Breedplan publishes four independent profitability indexes for different production strategies. They are the Self-Replacing Breeding $Index (SRI), Wagyu Breeder $Index (WBI), Wagyu Fullblood Terminal $Index (FTI), and Wagyu F1 Terminal $Index (F1I). The SRI and WBI are aimed at production systems where females are retained as herd replacements and each have different carcass value assumptions. FTI and F1I are aimed at production systems where all animals are intended for slaughter and again both have different carcass value assumptions. These indexes all have different weighted values for traits and attempt to consider production costs along with assumed carcass values. Read more about these on the Australian Wagyu Association’s website.

WSU Sire Summary 2017

The Washington State Sire Summary was last published in 2017. It is a Wagyu specific Estimated Progeny Difference (EPD) sire summary. It is computed using the BOLT genetic analysis system and published by Dr Charles T. Gaskins of Washington State University. The summary utilizes data exclusively from F1 or half-blood Wagyu in its analysis. In the latest publication 4,066 marble scores, 1,742 rib eye areas, 1,740 back fat thicknesses, and 1,352 hot carcass weights records were used to compute the EPDs.  It is important to note this EPD data is not directly comparable to other EBVs or EPDs calculated using other systems and data. The 2017 WSU Sire Summary publishes EPDs for Marbling, Rib Eye Area, External Fat, and Hot Carcass Weight.

Wagyu Recessive Disorders

Wagyu cattle are known to have six recessive genetic conditions. They are Erythrocyte Membrane Protein Band III Deficiency (Spherocytosis) (B3), Claudin 16 Deficiency (CL16), Chediak-Higashi Syndrome (CHS), Bovine Blood Coagulation Factor XIII Deficiency (F13), Factor XI Deficiency (F11), and IARS Disorder. The most prevalent in the Wagyu population are F11 and IARS Disorder. All are simple recessive disorders and easily managed through testing and mating decisions.

The following is a simple description of each: B3 homozygous have pernicious anemia, death normally occurs within the first week of birth. CHS homozygous have reduced immune response to disease, blood is slow to coagulate, pale coat color. CL16 homozygous have terminal kidney failure, onset can occur anywhere from late adolescence on. F13 homozygous have severe anemia, proteins for blood clotting missing or reduced. F11 homozygous have mild anemia often resulting in prolonged bleeding at castration or dehorning, mating carrier x carrier may have increased difficulty in producing viable embryos, generally non-lethal. IARS Disorder homozygous result in death of calves within the last weeks of pregnancy or shortly post birth, anemia, depression, weakness, etc. common.

SCD & Tenderness Tests

SCD: The Stearoyl CoA Desaturase (SCD) test was designed to identify cattle that exhibit a genotype that produces superior fat composition. Stearoyl CoA Desaturase (SCD) is an enzyme that changes stearic acid into oleic acid. There are two different alleles for this trait Valine (V) and Alanine (A). Therefore, the possible genotypes are AA, VA, and VV. One study found animals with the AA correlated to a lower melting point in intermuscular fat (IMF). This gene has no effect on marble score or other commonly measured carcass traits.

TENDERNESS Test: A conventional cattle test not applicable to Wagyu. Developed for and validated on Brahman, Brangus, Charolais, Red & Black Angus. A numerical 1-10 scoring scale based on the genotype of the tested animal at three different SNP locations.

Akaushi Association EPDs

The American Akaushi Association publishes some of the most extensive EPDs on Red Wagyu or Akaushi cattle. Their EPDs are based on data from F1 through Fullblood Akaushi cattle. They currently publish EPDs on Growth & Maternal Traits, Carcass Traits, and have two Indexes (Growth & Carcass).

Prefectural Analysis

The prefectural or 16/16 analysis is a Japanese pedigree analysis model that attempts to classify/group cattle by prefectural origin. This has been a common way to group and evaluate cattle prior to the development of EBVs and EPDs outside of Japan. This is also an especially useful tool in managing inbreeding during mating decisions. Traditionally F1 breeder have sought high % Tajima sires and Mr. Takeda’s rotational breeding system utilized this to classify sires. The Australian Wagyu Association has implemented its own Prefectural Analysis System into ABRI publishing a percentage Tajima, Kedaka, Tottori, Shimane, Itozakura, Okayama, and Hiroshima along with the pedigree and EBVs of each animal registered with them. The average Wagyu according to the Australian Wagyu Association’s analysis is 53.6% Tajima, 16.2% Itozakura, 7.6% Kedaka, 5.1% Shimane, 3.3% Tottori, 6.8% Okayama, 2% Hiroshima, and 5.4% Other.

Takeda Rotational Breeding

The idea of classifying cattle and breeding in a rotation to maintain balance and diversity is utilized in many breeds of cattle. This philosophy was popularized by Mr. Shogo Takeda in the Wagyu breed and is often referred to as the Takeda rotational breeding system. The principals of this system are that cattle are classified into four different groups (A,B,C,D) based on their characteristics. Group A consists of animals of with strong frame, growth, and calf raising. Group B are animals with extreme marbling and carcass traits that are small framed. Group C are animals with large frame, milk, and maternal traits. Group D consists of animals with strong marbling and carcass traits that are generally medium framed. Then cattle are bred in a circle with group A mated to group B, group B mated to C, group C mated to D, and completing the circle group D is mated to A. This, ideally, achieves similar results to the utilization of EBVs, by utilizing corrective mating of cattle to create balance. However, this system lacks any way of quantifying genetic gains achieved.


Wagyu Breedplan (EBVs)

EBV Enquiries: http://abri.une.edu.au/online/cgi-bin/i4.dll?1=3C212A07&2=2031&4=59272F59252D24252E232E2F2A&5=2B3C2B3C3A

About Wagyu Breedplan: https://www.wagyu.org.au/content/uploads/2020/09/AWA-BreedGuide2020.pdf


Wagyu $Indexes: https://www.wagyu.org.au/content/uploads/2020/06/BreedObject-Index-Comparison-2020-FactSheet.pdf



WSU Sire Summary

2017 WSU Sire Summary: https://wagyu.org/uploads/page/Washington%20State%20University%20Sire%20Summary.pdf

Wagyu Recessive Disorders

AWA Genetic Condition Fact Sheet:  https://www.wagyu.org.au/content/uploads/2020/08/Genetic-Conditions-in-Wagyu-FactSheet-2020.pdf

Foundation Sire Recessives Fact Sheet: https://www.wagyu.org.au/content/uploads/2020/08/IARS-Foundation-Sires-Aug-2020-v2.pdf

AWA Original Fact Sheet 2014: https://wagyu.org/uploads/page/Inherited%20Recessive%20Traits%20in%20the%20US%20Red%20%20Black%20Wagyu%20Breed_v5(1).pdf

SCD & Tenderness Testing

SCD Test Summary: https://wagyu.org/uploads/page/EXON%205%20and%20SCH%20tests%20for%20Japanese%20Black%20Cattle(2).pdf

SCD Test Data: http://www.rocking711.com/wp-content/uploads/2018/02/SCD-Gene-Japanese-Study-Paper-Taniguchi-4-2-2003.pdf

Test Summary: https://wagyu.org/uploads/page/Igenity%20Tenderness%20Marker.pdf

Test Validation: https://www.nbcec.org/validation/igenity/tenderness.html#summary

Akaushi Association EPDs

EBV Data Base: https://akaushi.digitalbeef.com/

Progeny Tested Sire List: https://akaushi.digitalbeef.com/modules/UpDownload/store_folder/Sire_Summary/Akaushi%202020%20Spring%20Progeny%20Tested%20Sire%20Listing.pdf

Prefectural Analysis

AWA Fact Sheet- Prefectural Analysis: https://www.wagyu.org.au/content/uploads/2020/08/AWA-FACTSHEET_prefectural-bloodlines.pdf

Traditional Prefecture Bloodlines: https://australianwagyuforum.com.au/traditional-bloodlines/


Takeda Rotational Breeding

Rotational Breeding Summary: http://www.wagyuinternational.com/rotation.php

Takeda Rotation Information: http://www.rocking711.com/16×16/