Written By Ron Metz, Vice President PDCA
Photo - Pepper, owned by Rick and Eliena Bodtke
Phenotype Testing
In this second part of the DexStar series, I will be talking about the initial phenotype testing that will take place and how to enroll in the program. As I mentioned in the first article it will take time to develop protocols for genetic tests on beef and milk quality. In the meantime, PDCA has to begin compiling a database for Dexter cattle. It is important when launching a new breed testing initiative to not overwhelm the membership with requirements. Data collection will start with some basic phenotype evaluations and scoring. Keep in mind cattle breeds involved in the production of commodity beef and dairy products concern themselves with phenotype evaluations that put emphasis on quantity. Because our breed goals are focusing on markets outside the commercial commodity production arena, DexStar will be measuring values that emphasize the quality of Dexter beef and milk and traits that have a direct effect on that quality.
Female Evaluation
DexStar is scheduled to launch in early 2022 with the focus on Dexter females. Four basic phenotypes have been chosen for phase one of female evaluation and scoring. The categories will be hip height measurement (at the hook bones), udder evaluation, rear feet/legs evaluation and temperament evaluation. Scores will range from 1-5. One being the lowest score and 5 being the highest. A PDCA guide is being developed which will provide explanations on how to do evaluations and scoring. Illustrations of what is unacceptable (scored low) and ideal (deserving of a high score) in each phenotype category will be included. I chose these phenotype categories because they represent the areas our females need the most improvement in.
Hip height measurement is critical in maintaining the breed’s correct size. Maintaining a correct size will directly affect our breed’s ability to capture new markets outside commodity beef and dairy, keep input and maintenance costs low and preserve calving ease. Evaluation of rear feet/legs addresses mobility, productivity and longevity issues. An animal with weak rear feet, poor leg structure and incorrect angulation will not have as long of a productive life within the herd compared to an animal that is strong in those traits.
One of the biggest problems I see in our breed is an abundance of very poor udders. It is of the utmost importance we pay special attention to the improvement of udder size, front and rear attachment, suspensory ligament strength, teat size and teat placement. Udder and teat problems directly affect milk production and milking by hand or machine. The ability of a calf to nurse is seriously impacted by a poorly made udder. This can result in a negative impact on growth and development of the calf. Pendulous udders with poor front and rear attachment can lead to serious udder and teat damage. A weak suspensory ligament and collapsed udder floor will cause teats to splay outward affecting milking ability.
The fourth category, temperament, is substantially heritable and addresses safety issues. Whether horned or polled, a Dexter female significantly outweighs any human and can cause considerable harm if ill-tempered or flighty. Temperament should be taken seriously, evaluated honestly and scored accordingly. Scores can be used to identify females that need to be culled and bloodlines that produce temperament issues.
There are some important requirements to adhere to when doing phenotype evaluations and scoring. First, females being scored have to be from the same peer group (two or more animals of the same sex within an age group). An example of this would be heifers 12-24 months. Specific categories and age groups for female evaluations will be outlined in the PDCA guide. Second, it is very important only one person be designated to do all the evaluations and scoring for the herd. Ask two people what they think of an animal and you will get two different opinions resulting in two different scores. Inconsistencies in scoring caused by more than one person doing evaluation and scoring on a herd can be detected. Algorithms in the program generating EPD values (expected progeny difference) can identify inconsistencies which may cause data to be invalid and not used.
The higher the value of a score in each phenotype category, the more likely a given female will produce offspring showing improvements for a given trait. Low score values will identify areas needing improvement and help you avoid perpetuating problems in your herd. Lastly, it is very important to be critical when evaluating your females. “Barn blindness” will not help you improve your herd or the breed. Evaluate and score ruthlessly with an eye towards increasing quality and value. Identifying strengths and weaknesses through realistic scoring will give you the ability to make better selection and breeding decisions thus improving the performance and value of your herd.
Enrollment
Enrolling your herd in DexStar is easy. Contact Deb Botruff, PDCA Registrar, at PDCA.registrar@dexterstoday.com . When enrolled, your PDCA breeder number will be assigned as your DexStar number. Each owner enrolled will receive a certificate indicating their participation in DexStar. Participants name, farm or ranch name and contact information will be added to a published list of DexStar breeders. Again, 2022 will be the year of the Dexter female. Initial focus will be on the enrollment and data collection on Dexter female peer groups. Bull enrollment, evaluation and scoring will be added at a later date. Females entered in DexStar will need to be registered with the PDCA. Owners participating in DexStar are required to be PDCA members. Indicate to the registrar the number of females you will be entering in the program along with their names, registration numbers and dates of birth. When DexStar phase one female testing is officially launched, each owner will receive an evaluation/scoring guide and score sheets. When you are finished with the evaluation and scoring of each female you entered, return a copy of the score sheets to the PDCA registrar. The scores will be recorded on each female’s registry information as part of their permanent record.
DexStar is an exciting new program that has never been implemented before with the Dexter breed. By participating in the program not only will you have a hand in improving the breed, you will also have a tool to use for the improvement of your herd. Through the use of DexStar data you will be able to make better selection and breeding decisions thereby increasing your herd value. A tested herd is a proven herd. I encourage all Dexter owners to seriously consider enrolling. Enrollment will open January 15, 2022. Announcement of the official launch of DexStar phase one testing will follow.
