Impacts of Dam Age on Lifetime Productivity of Angus Replacement Beef Females

SIMPLE SUMMARY: Selecting replacement beef females is often based on individual producers and their own individual needs. Selection criteria typically vary from producer to producer but generally include productivity of the mother, ability to rebreed and wean a heavy calf. Increased longevity of the dam may be an indicator of potential productivity of their female offspring. Greater longevity of females with beef herds allows producers to be more selective when choosing replacement females; although, this may increase generation intervals. Using comprehensive cow-calf production data can help improve overall selection criteria associated with cow-calf productivity such as reproductive ability, weaning weights of offspring and ability to remain in the herd. ABSTRACT: Comprehensive cow-calf production data was utilized to evaluate the impact of dam age on lifetime productivity of Angus replacement beef females. Cows used in this study were commercial Angus replacement females born between 2006 and 2020, ranging in age from 1 to 14-yr of age (n = 3568). To determine the impact of dam age on lifetime productivity, cows were classified by age groups, specifically 2-, 3-, 4-, 5-, 6/7-, and 8-yrs old and older. The 8-yr and older group consisted of females that were up to 14-yr of age. Cow BW at breeding exhibited a cow age × dam age interaction (p < 0.01). Cows at 5-yrs of age from 2-yr old dams weighed less at breeding than cows at 5-yrs of age from 3-, 4-, 5- and 8-years and older dams, with cows at 5-yr of age from 6/7-yr old dams being intermediate. The probability of remaining in the herd at the age of 5 was significant for dam age (p = 0.05) averaging 69.41%, but after further delineation, no significant impacts of dam age were observed. Productivity as a measure of total pounds of calf weaned through 5-yrs displayed a dam age effect (p = 0.01) with cows from 8-yrs or older dams weaning more total pounds of calf, than cows from 3-yr-old dams. In summary, the impact of dam age on lifetime productivity indicates that dam age can impact future productivity of their offspring.