Using Herd Genetics

Table of Contents

Name & Class Info

Give your class a name and, if you'd like, a short description. Both are shown to your students on their dashboard, so pick something they will recognize (for example, "Period 3 Animal Science" or "Fall 2026 Dairy Genetics"). You can rename your class or update its description at any time from the class settings page. Changing them does not affect any student data or progress.

Selecting a Traitset

Herd Genetics uses "traitsets" to give each class its own set of traits. A traitset is chosen for the whole class, so every student sees the same recessives and traits, even though each student may work with a different type of animal. Different classes can choose different traitsets to study different parts of genetics. Some classes need a complete set of traits tied to an industry, such as the dairy cattle industry's "ANIMAL_SCIENCE_422" traitset. Other classes need a more general set of traits and more types of animals, such as "ANIMAL_SCIENCE_322." You can compare the options using the traitset reference.

Note: the traitset cannot be changed after your class is created. Changing it would invalidate every animal and breeding record your students have already built. If you are unsure, compare options in the traitset reference before you finish creating your class.

Every trait in a traitset has a few core values that control how it behaves genetically. For example, the MILK trait in ANIMAL_SCIENCE_322 has a base standard deviation of 567, a heritability of 0.2, an inbreeding depression percentage of -73.4, and a net merit value of $0.02. The DPR (Daughter Pregnancy Rate) trait has a base standard deviation of 1.4, a heritability of 0.04, an inbreeding depression percentage of -0.22, and a net merit value of $11.

Each trait is shown differently depending on the type of animal, because the same genetics can mean different things in different livestock. For Holstein Dairy Cattle, MILK is shown as Milk Yield, measured in pounds, with a mean of 18,000 and a standard deviation of 567. DPR is shown as Daughter Pregnancy Rate, measured as a percentage, with a mean of 30 and a standard deviation of 1.4. For Beef Cattle, MILK is shown as Wean Weight, measured in pounds, with a mean of 450 and a standard deviation of 40. DPR is shown as Daughter Pregnancy Rate again, with the same mean of 30 and standard deviation of 1.4.

Setting Up Your Initial Class Herd

The class herd is the one herd that all students share. Every animal your students submit is added to it. Students can also use it to find sires (bulls) outside of their own herds, which helps when a student's herd does not have enough genetic diversity for a particular cross.

When you set up the class herd, you choose its starting males and females. Males become the sires available to the whole class, so their individual genetics matter. Pick males with a range of traits so students have real breeding decisions to make. Females mainly affect the class herd's starting averages and do not change any one student's results much, so their individual makeup matters less.

Note: the initial class herd animals cannot be changed after your class is created. Review your selections before you finish setup.

Enrolling Students in Your Class

After you create your class, you are taken to the class page. You can also reach the class page from the home page. The class page shows your class code, which students use to enroll. To enroll, a student selects the join class button on the home screen, enters the class code, and sends an enrollment request. You must accept the request before the student is enrolled.

To accept requests, go to the management section of the class page and click the enrollments button. On the enrollments page you can accept or deny each student's request. After a student is enrolled, you can also view their individual simulations from this page.

Note: each student you accept uses one enrollment token. Each class starts with five enrollment tokens. To enroll more students, click the request enrollment tokens button on the enrollments page. Tokens are limited to prevent misuse of Herd Genetics.

Changing the Default Animal Lens

The animal lens is the type of animal that students see their traits expressed through, such as Holstein Dairy Cattle or Beef Cattle. You can change the default animal lens using the select on the class page. If you want all students to use the same animal lens, there is a field on the class page for that as well.

Allowing Students to Rename Herds

If you want students to be able to rename their herds, turn on the allow herd rename field on the class page.

Calculating PTAs

You can recalculate the PTAs of the animals in your class using the Calculate PTAs button. If you want to run genomic testing to make the PTAs more accurate, use the Run Genomic Testing & Calculate PTAs button instead.

PTAs become more accurate after sires have progeny. Because of this, you need to recalculate PTAs to match real life accuracy. If you do not recalculate, the PTAs will stay based on the sire having no progeny.

Downloading Animal Data

Every animal in the class simulation is available through the Download animal data button. This gives you a CSV file with every animal in the simulation, both dead and alive.

Information Visibility

By default, students can see all of the genetic information for every animal. To hide some of it, change the visibility fields on your class page: Net merit visibility, Hide female pta, Genotype visibility, Phenotype visibility, Pta visibility, and Recessive visibility.

Creating Assignments

Students complete all of their work through assignments. To create an assignment, go to the management section of the class page and click the assignments button. On the assignments page you can create new assignments and view past assignments, including their completion status.

Each assignment is made up of steps, and students must complete the steps in order. There are three types of steps:

  1. "Submit Male": the student submits a male animal to the class herd.
  2. "Submit Female": the student submits a female animal to the class herd.
  3. "Breed": the student breeds their herd and advances their simulation by one generation.

Note: by default, animals are added to the class herd right away. To hold submitted animals in quarantine first, set the quarantine days option on your class page.

After you create an assignment, students can view it from the home page or from their herd page.