Table 2.

Effects of late gestational nutritional plane of primiparous beef females on calf size at birth

	Nutritional plane1
Item	Control	Nutrient Restricted	SEM2	P-value
Gestation length, d	278	279	1	0.46
Calf sex, % male	66.7	69.2	–	–
Assisted calving, %	16.7	30.8	–	0.64
Abnormal presentation, %	0.0	23.1	–	0.22
Calf size3
Birth weight, kg	30.7	29.9	1.5	0.72
Shoulder to rump length, cm	55.4	55.0	0.9	0.76
Heart girth, cm	70.2	69.1	1.1	0.46
Abdominal girth, cm	63.3	62.5	1.2	0.64
Flank girth, cm	58.2	56.9	1.3	0.48
Cannon circumference, cm	11.5	11.3	0.2	0.49
Cannon length, cm	17.2	17.7	0.3	0.27
Coronet circumference, cm	17.7	17.4	0.3	0.35
Height at shoulder, cm	67.0	66.6	0.7	0.68
Calf ponderal index4, kg/m3	180	180	6	0.99
Heart girth:length5	1.27	1.26	0.01	0.50
Volume6, L	17.9	17.2	0.9	0.57
Longissimus muscle area7, cm2	10.8	11.2	0.7	0.65
Birth weight8, % initial dam body weight	6.88	6.58	0.32	0.52
Birth weight9, % final dam body weight	6.43	7.23	0.33	0.09

¹Primiparous dams were individually-fed either 100% (Control) or 70% (Nutrient Restricted) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to parturition.

²Standard error of the mean for Control (n = 12) and Nutrient Restricted (n = 13).

³Calves were weighed and measured at 0.9 ± 0.3 h (SD) of age (pre-suckling).

⁴Ponderal index = calf birth weight (kg)/shoulder to rump length (m)³.

⁵Ratio of heart girth (cm):shoulder to rump length (cm).

⁶Volume (L) = [π × average girth radius (cm)² × shoulder to rump length (cm)]/1,000.

⁷Determined at 7 d of age.

⁸Dam body weight before dietary treatment initiation (days 158 and 159 of gestation).

⁹Dam body weight post-calving (days 1 and 2 of lactation).