Relationships between maintenance energy EPD and performance measures of progeny from Red Angus sires divergent for maintenance energy EPD
The Red Angus Association of America (RAAA) developed the maintenance energy (MEM) EPD as an estimator of maintenance requirements, in an attempt to lower cow maintenance costs within the breeding herd. However, no studies have evaluated the selection and incorporation of MEM EPD into breeding programs, and the resulting effects upon progeny postweaning performance. Conducted as part of a larger study, postweaning performance measures were recorded in three birth year contemporary groups from the progeny (n = 222) of sires (n = 12) divergent for MEM EPD. The objective was to evaluate relationships between various phenotypic performance measurements and EPDs of progeny and sires. Sires were partitioned into high and low MEM EPD groups based on the RAAA breed average for MEM EPD. Sire MEM EPD was found to be positively correlated (P < 0.05) with progeny phenotypic performance measurements including ADG (r = 0.32), DMI (r = 0.21), and metabolic BW (MBW; r = 0.22), while being negatively correlated with progeny feed-to-gain ratio (r = -0.21). In addition, sire MEM EPD was also positively correlated (P < 0.05) with progeny ADG EPD (r = 0.43) and MBW EPD (r = 0.24). No association (P > 0.05) was observed between sire MEM EPD and progeny DMI EPD. Therefore, our data analyses indicate that sire MEM EPD is associated with growth and BW in Red Angus-sired cattle.
maintenance energy, performance, Red Angus