Predicted Transmitting Ability (PTA) is the part of an animal's genetic makeup that is transmitted to offspring. PTAs have the same genetic base, the same meaning, and the same interpretation for does and buck. PTAs are published for milk, fat, protein, component percentages, and the economic indexes PTA$ from milk and fat, PTA$ including protein, and Cheese Yield Dollars. PTAs are also published for linear appraisal final score and each individual type trait.
Examples:
A PTA value of 200 lbs milk is the expected difference in a single lactation 305d-2X-ME milk yield between the daughters, on average of the animal with PTA = 200 and the daughter average of an animal with PTA = 0. 0 being the average for the breed. PTA does not tell how much milk a daughter of a sire will give. PTAs only have meaning relative to PTAs on other animals.
A PTA value of +1.5 for the Fore Udder Attachment linear trait is the expected standard deviation of the daughters, on average, of an animal with PTA = +1.5 and the daughter average of an animal with a PTA = 0. 0 being the average for all. PTA does not tell what the actual raw linear score will be.