Table 7.

Effects of level and source of fat in the diet prepartum of beef cows on the performance of their progeny

	Treatments2				Contrasts3
Item1	LF (n = 10)	CAN (n = 10)	FLX (n = 10)	SEM	LF vs. HF	CAN vs. FLX
At birth
Date, Julian d	114	113	115	1.65	0.87	0.52
BW, kg	40.2	42.4	43.3	1.08	<0.01	0.24
First 42 d
BW, kg	61.8	65.9	65.8	1.22	<0.01	0.94
Cumulative ADG, kg/d	1.04	1.06	1.07	0.05	0.55	0.74
At weaning
Age, d	183	184	183	1.85	0.71	0.52
BW, kg	248	260	251	8.39	0.05	0.05
Cumulative ADG, kg/d	1.13	1.19	1.13	0.05	0.18	0.03
BW180, kg	244	256	247	9.19	<0.05	<0.05
Backgrounding period
Final BW, kg	411	433	420	5.59	0.02	0.14
Backgrounding ADG, kg/d	0.91	0.97	0.95	0.02	0.07	0.46
Cumulative ADG, kg/d	1.02	1.08	1.04	0.02	0.07	0.14
BW365, kg	413	437	423	7.94	0.03	0.15
Finishing period
Final BW, kg	603	639	620	9.88	0.03	0.21
Finishing ADG, kg/d	1.90	2.04	1.97	0.06	0.16	0.43
Cumulative ADG, kg/d	1.22	1.29	1.24	0.02	<0.05	0.16
Shrunk BW, kg	579	614	595	9.61	0.03	0.19
At slaughter
Age, d	463	465	463	10.4	0.55	0.30
HCW, kg	339	361	349	5.51	0.02	0.16
Dressing, %	58.5	58.8	58.7	0.27	0.48	0.77
Quality grade, %
AAA	78.6	78.7	84.2	12.9	0.68	0.54
AA	16.8	17.6	9.7	14.8	0.57	0.29
A	0.0	0.0	0.0	–	–	–
Yield grade, %
3	49.6	53.6	46.9	20.7	0.95	0.60
2	32.6	38.9	40.6	18.6	0.46	0.89
1	14.2	5.3	10.6	4.99	0.25	0.41
LMA, cm2	84.5	85.2	83.2	1.23	0.86	0.23
Fat thickness, mm	12.7	13.7	12.7	1.52	0.51	0.37
Marbling score	444	452	443	10.7	0.78	0.61

¹Cumulative ADG = average daily gain from birth; BW180 = body weight adjusted to 180 d; BW365 = body weight adjusted to 365 d; HCW = hot carcass weight; LMA = longissimus muscle area.

²LF = cows fed a low-fat diet; CAN = cows fed a high-fat diet including a canola seed–based pelleted feed; FLX = cows fed a high-fat diet including a flaxseed-based pelleted feed.

³HF = average of CAN and FLX.