Table 1.

Estimates of NEm (Mcal/d) required for pregnancy in beef cattle^†

Day of gestation	NRC (1996, 2000)	NRC (1984)	CSIRO (1990)
130	0.327	0.199	0.280
160	0.634	0.505	0.509
190	1.166	1.083	0.923
220	2.027	1.952	1.673
250	3.333	2.916	3.029
280	5.174	3.518	5.478

^†Estimates are based on a calf birth weight of 38.5 kg. Adapted from NASEM (2016).