EPDs Expected Progeny Differences

1. ‘EPDs’Expected Progeny Differences Jeanne Dietz-Band, Ph.D. Kiko EPD Program

2. Definition

3. How Do EPDs Differ from Visual Inspection and Antidotal Evidence? Genetics are variable …..no commercial performance traits are 100% heritable >EPDs estimate the performance of each offspring based upon the performance evaluation of the parents as well as all the near relatives What part of performance is due to genetics and what part to management/environment? >EPDs make proven statistical adjustments in the data evaluation that minimize the effects of different management styles

4. How Do EPDs Differ from Visual Inspection and Antidotal Evidence?(cont.) Visual inspection and casual observations do not predict genetic performance > EPDs provide a way to quantitatively predict genetic performance while providing meaningful comparisons between Kikos in different herds SHOW me the data! >Breeders that fully participate in the EPD program are demonstrating that they are making breeding and culling decisions with the intent to improve genetic performance. EPDs raise the commercial value of their Kikos

5. How do EPDs Differ from On-Farm Performance Testing? Ratios and indexes have real value in comparing Kikos within the same herd . On-farm testing methods have value in daily decision making and in herd management On-farm performance testing is not optimal for looking a traits with low heritability. On-farm performance testing does not allow comparisons between herds > EPDs can be used to compare Kikos within a herd, compare Kikos across herds, evaluate traits of low heritability, and also identify over time which genetic lines within the Kiko breed are superior for specific performance traits.

6. How do EPDs Differ from Central Performance Testing? Using Central Performance tests as a competition for highest ‘average daily gain’ is a misunderstanding of the value of such a test. ‘Central Performance tests should be used for progeny testing (testing as many kids as possible out of the same sire). Central Performance testing (Oklahoma and Maryland) DO provide valuable information about parasite resistance and resilience >EPDs provide more robust and meaningful information about the ability of the progeny of a Kiko to gain well. > EPDs do not currently evaluate parasite data

7. How About an Example? You want to buy a doe for your herd that will most likely give you twins every year. Doe A – is a twin and the breeder tells you her dam was a twin. The doe is also black with a cute white spot on her nose. Her picture was in a flashy color ad placed in Goat Rancher. Doe B – is a twin, 97% of all the kids born on the farm are twins, and the doe’s dam and grand-dam had twins every breeding. The breeder shows you all the data and goes over it with you ad nauseum (…….snore). The doe is white. She never appeared in Goat Rancher. > EPDs do the same thing as the critical evaluation above. They gather all the important information in order to estimate future genetic performance.

8. The Birth Weight EPD Estimates the effect of a Kiko’s genes on prenatal growth Depends upon the average birth weight in the herd Identifies genetic lines predisposed to producing excessively heavy or excessively light kids

9. The Uterine Capacity EPD Measured in pounds Depends on the frequency of overweight vs. underweight kids in the herd A more direct measure of a specific doe’s maternal genetic effects on birth weight Identifies does whose daughters may be predisposed to producing heavier or lighter kids other than those identified by the birth weight EPD

10. The Uterine plus Birth Weight EPD The sum of the Uterine Capacity EPD plus one half the birth weight EPD Recognizes that a doe’s genetic contribution to birth weight is a combination of her uterine capacity and a sample one half of her genes Provides an index (no prediction error reported) of the total anticipated contribution of a Kiko’s daughters to the birth weight of their kids

11. 90-Day Weaning Weight EPD An estimate of preweaning growth potential

12. Maternal Milk EPD Expressed in pounds of kids weaned, not pounds of milk produced Identifies individual does whose kids grow faster to weaning than predicted by the weaning weight EPDs of her parents Dams with a high Maternal Milk EPD are assumed to produce more milk

13. Milk plus Growth EPD Provides an index (no prediction error reported) of the total anticipated contribution of a Kiko’s daughter on the weaning weight of her kids It is the sum of the Maternal Milk EPD and one half the 90-Day Weaning Weight EPD Combines the effects of her milk production and a sample one half of her genes for preweaning growth potential

14. 150-Day Postweaning Weight EPD Combines information on preweaning and postweaning weights to predict the genetic contribution attributed to postweaning growth This EPD is used to predict genetic differences in market weights when marketing is done at a constant age other than at weaning

15. Percent Kid Crop EPD Evaluates genetic potential for prolificacy Expressed as number of kids born per 100 does kidding Used to identify Kikos whose daughters are predicted to have more kids during their years as a commercial dam

16. Avoid Single Trait Selection IF a breeder is constantly selecting for higher EPD values of a single trait, they run a very significant risk that over time other important commercial traits will be lost in the herd. Strive to achieve a productive balance of contributing genetics in your herd

17. Sample EPD Data

18. Prediction Errors The Prediction Error is a measure of the anticipated stability of an EPD. As a substantial amount of performance data accumulates on a Kiko, the EPD values becomes increasingly stable and accurate

19. Prediction Errors The Prediction Error is a measure of the anticipated stability of an EPD. As a substantial amount of performance data accumulates on a Kiko, the EPD values becomes increasingly stable and accurate

20. Prediction Errors (cont.) There is about a 0.33 chance that a Kiko’s EPD for a given trait will change by more than the amount of the prediction error. There is approximately one chance in 20 that an EPD will change by more than two times the prediction error. There is one chance in 385 that an EPD will change by more than three times the prediction error

21. Sample EPD Data

22. Suggested Guidelines for Using EPDs and Prediction Errors Choosing Bucks: Young buck with high EPDs and high prediction errors vs. Older Progeny-tested buck with good EPDs and low prediction errors

23. Suggested Guidelines for Using EPDs and Prediction Errors (cont.) Choosing Does: Differences in prediction errors among does in a breeding herd are almost never large enough to be important Concentrate on the EPD values to make selections for breeding and culling

24. The Goal To select groups of replacement does and bucks that will provide consistent genetic improvement. Larger herds can pay less attention to prediction errors and concentrate on the difference between individual Kikos to average out future changes in EPDs Small, single sire, herds will need to place greater emphasis on prediction errors to enhance the potential for genetic progress

25. Reference Sire Ideally a progeny-tested buck with good performance data and a well balanced set of EPDs Identifying reference sires is not about finding vastly exceptional bucks, it’s about creating genetic linkages between herds Semen needs to be readily available and provided nearly ‘at cost’ to make it easy for all breeders to fully participate in the EPD program

26. Artificial Insemination (AI) Realize that without the widespread use of AI, the meat goat industry will never have the large number of proven sires found in the beef and dairy cattle industry

27. New EPDs to Consider EPDs for parasite resistance EPDs for carcass traits that yield a better meat to bone ratio

28. Is the Kiko goat the ideal breed for the commercial meat goat industry? What does it mean to successfully raise commercial meat goats? Is it time to get serious and to work together to see that the Kiko breed reaches its full potential as a meat producing animal? Is it time to quit putting so much false value in pedigrees, pictures, and hype without proven performance data?