| Autor: |
Wellnitz KR; Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717, USA., Parsons CT; Northern Agricultural Research Center, Montana State University, Havre, MT 59501, USA., Dafoe JM; Northern Agricultural Research Center, Montana State University, Havre, MT 59501, USA., Boss DL; Northern Agricultural Research Center, Montana State University, Havre, MT 59501, USA., Wyffels SA; Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717, USA., DelCurto T; Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717, USA., Van Emon ML; Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717, USA. |
| Abstrakt: |
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. |
