Relationships between maintenance energy EPD and performance measures of progeny from Red Angus sires divergent for maintenance energy EPD

Abstract Text:

The Red Angus Association of America (RAAA) developed the maintenance energy (ME_M) 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 ME_M 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 ME_M 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 ME_M EPD groups based on the RAAA breed average for ME_M EPD.  Sire ME_M 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 ME_M 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 ME_M EPD and progeny DMI EPD.  Therefore, our data analyses indicate that sire ME_M EPD is associated with growth and BW in Red Angus-sired cattle.

Keywords:

maintenance energy, performance, Red Angus