Research Summaries: Canola and Peas in Livestock Diets

Feeding Canola Meal to Grower/Finisher Cattle

Canola meal is the most common protein supplement for ruminants in Canada (Anonymous 1993) and can compete with SBM as an economical protein supplement (Moshtaghi Nia and Ingalls 1995 {827}; Parker 1992).

Steer and Bull Performance

Results using CM in grower and finisher diets in North American diets are shown in table 4. Protein supplementation improves the weight gain of growing beef steers fed a silage diet (Petit and Veira 1994 {853}; Petit et al. 1994 {862}; Seoane et al. 1993 {921}). Crossbred steers (194.4 1.5 kg) fed CM or fishmeal (FM) at 95 g CP/100 kg BW, and a medium quality hay or silage had ADG 43% higher for protein supplemented steers compared with ADG of steers receiving no protein supplement (P < 0.01). The response in ADG to protein supplementation depended on the type of forage fed. When the forage was hay, CM or FM equally improved ADG (by 37.2 and 41.8%) compared to the control (Seoane et al. 1993 {921}). An increase in steer performance fed hay was also reported by Seoane et al. (1992 {956}). When the forage was silage, steers fed CM or FM had improved ADG (33.3 and 61.5%, respectively) than the control, indicating an interaction between protein sources and type of forage (P = 0.06).

Table 4. Performance of steers fed canola meal
Reference	Animal	Basal diet	Treatment	ADG
Seoane et al. 1993 {921}	Crossbred steers (194.41.5 kg)	Medium-quality hay or silage + barley	Control vs. CM or FM supplied 95 g of CP/d/100kg BW	Hay - CM and FM ADG by 43% (0.43 vs. 0.61 kg; P<0.001) Silage-CM ADG by 33.3% (0.39 vs. 0.52 kg), FM ADG by 61.5% (0.39 vs. 0.63 kg) indicating a forage x protein interaction (P=0.06)
Seoane et al. 1993 {956}	Crossbred steers (2825.5 kg)	Quackgrass hay	400 g/head/d	CM ADG by 60% (0.93 vs. 0.58 kg; P < 0.001)
Petit et al. 1994 {862}	Crossbred steers (227 kg)	Timothy silage	3.6, 5.5, 7.5 and 15% CM	CM ADG (0.57 vs. 0.95, 1.09, 1.09 and 1.22 kg; P < 0.05)
Petit and Veira 1994 {853}	Crossbred steers (226 kg)	Silage + FM, SBM, 60% corn gluten/40% blood meal, CM and meat meal	All diets supplied 250 g of CP/h/d	-protein supplement in the finishing phase had no effect -protein supplementation overall CM ADG P<0.05
Jacobs and Mc Allan 1989 {1061}	Friesian steers	Silage + enzymes Silage + formic acid	0, 6, and 12% CM	CM ADG (0.49 vs. 0.91; P<0.01) with enzyme supplemented silage but not formic acid treated silage

Compensatory growth was obtained during the grazing period. Steers that showed lower ADG during the wintering period were the ones that obtained higher ADG during the grazing (r = -0.46, P < 0.01)(Seoane et al. 1993 {921}). After a 62 d grazing period, the effect of winter protein supplementation on body weight had almost disappeared (Seoane et al. 1993 {921}). Conversely, in another study, large framed crossbred steers (266 kg) were fed 5 different protein sources (FM, SBM, 60% corn gluten/40% blood meal, CM and meat meal) providing 250 CP g/hd/d through the grower period (168 d). For the finishing phase half the steers were placed on a diet consisting of 30% high-moisture ear corn and 70% grass silage (DM) and the other continued to receive protein supplements that supplied 125 g CP/h/d. Protein supplements during the finishing period had no effect on intake or animal performance. However protein supplementation in the grower phase effected BWG (P=0.07), feed:gain ratio (P < 0.05) and days to market (P < 0.05) during the finishing phase. Steers supplemented with protein supplements were heavier at the beginning of the finishing phase. Days to market were less (P < 0.05) for steers fed FM compared to other protein sources. All other protein sources had fewer days to market compared to steers fed silage alone (P < 0.05). The improvement in BW gain overall resulting from protein supplementation during growth was sufficient to reduce the number of days required to reach market weights (Petit and Veira 1994 {853}). Other studies support these findings. Large-framed crossbred steers (227 kg) were placed on a grower period for 24 wk. Supplementation with 3.6, 5.5, 7.5 and 15% CM increased ADG (P < 0.05), improved feed effeciency (P < 0.05) and reduced (P < 0.05) days on feed. In the finisher phase the differences in DMI, ADG and feed efficiency observed during the growing phase disappeared or were reversed. However, over the entire trial, performance measures indicated that the inclusion of CM in silage-based diets of beef cattle increased ADG and reduced days to market. Petit et al. (1994 {862}) concluded that feeding 7.5% CM to silage-fed animals was the best strategy to decrease days on feed and maintain reasonable feeding costs for fattening.

Canola meal has shown equivalent performance in comparison to traditional protein supplements, FM and SBM. Jacobs et al. (1992 {965}) reported higher LWG for RSM supplemented steers compared to steers fed FM fed treated silages, but the difference was not significant. Both RSM and FM produced similar responses when fed isonitrogenously. Beef steers (initial 228 kg) fed an increasing amount of RSM (118 mol/ g of GL) replacing SBM had similar ADG (mean SE = 1.26 .033 kg/d) and feed efficiency (mean SE = .153 .003) (Lardy and Kerley 1994 {851})(table 5).

Table 5. Diet composition and performance of steers fed increasing amounts of RSMz
Ingredient (% DM)	0% SBM 100% RSM	33% SBM 67% RSM	67% SBM 33% RSM	100% SBM 0% RSM	SEM
RSM	67.74	45.31	22.77
SBM		22.16	44.54	67.25
Ground corn	32.26	32.53	32.69	32.75
Nutrients
CP (%)	31.36	32.26	31.88	29.71
GL content (mol/g)	104.0	70.3	35.73
Performance
Daily gain kg/steer/day	1.23	1.23	1.32	1.27	.033
DM intake kg/steer/day	7.89	8.11	8.61	8.53	.154
CP intake kg/steer/d	0.95	1.01	1.06	1.03	.017
Feed efficiency gain/feed	0.156	0.152	0.154	0.149	.003

^zLardy and Kerley 1994 {851}.

Studies with a low and high % CM intake have reported positive results. McKinnon et al. (1993 as cited by Christensen and McKinnon 1993) fed recently weaned large frame calves 23% CM or a urea based ration. Canola meal supported higher ADG (1.3 vs. 1.2) compared to the urea-based ration. No treatment effect was observed for daily FI, feed conversion ratio or carcass quality. In another study, CM supplemented up to 30% of the ration fed to weaned calves or backgrounded yearlings without adversely affecting FI, daily gain or feed conversion ratio (table 6). Positive results with a low % CM supplement have had responses. Holstein steers (100-500 kg) were supplemented with three different diets; 85% grass hay/15% concentrate, same + 10g/kg formaldehyde (FA)-treated CM and 85% concentrate/15% grass hay (Mears and Schaalje 1993 {910}; Bailey 1989 {1052, 1075}). All diets were formulated to provide 0.95 MJ DE/d/LWG^0.75 (Bailey 1989 {1052, 1075}). Supplementing the forage with FA-CM increased daily empty liveweight gains by 13% and reduced the extra-maintenance energy requirement per unit weight gain by 12% even though the forage diet was adequate in protein. Supplementation of hay diet with rumen undegradable protein increased efficiency of gain by increasing protein gain, not fat (Bailey 1989 {1075}). The use of FA-CM improved the efficiency of beef production from forage diets without contributing to the deposition of excess fat (Bailey 1989 {1052}). Conversely, a study (Mears and Schaalje 1993 {910}) with the same diets and Holstein steers (100 to 450 kg) reported no increase in ADG of calves.

Table 6. Performance of beef cattle fed diets containing different levels of CM (2.84 Mcal DE/kg DM)z
	Level of CM (% DM)
	4.3	11.5	21.7
FI (kg/d)
Weaned calves	8.0	8.1	8.3
Yearlings	10.3	10.7	10.1
Daily gain (kg)
Weaned calves	1.4	1.5	1.5
Yearlings	1.6	1.5	1.6
Feed:gain
Weaned calves	5.7	5.5	5.5
Yearlings	5.8	6.4	6.2

^zMcKinnon et al. 1993 as cited by Mustafa (1996).

Bulls, especially continental crosses, have a higher requirement than steers for digestible undegradable dietary protein (ARC 1984 as cited by Grundy et al. 1996 {805}). The variation in increasing ADG with RSM supplementation to bulls was comparable to steer performance (Jacobs and McAllan (1992 {959}; {1061}; {960}) and Jacobs et al. (1992 {965}). The sooner the experiment ended, the lower the concentrate fed and the poorer quality forage or silage (short on AA or peptides) fed, the greater the ADG and carcass percentage (Pullar 1995 {830}; Varvikko 1987 {1130}) response to RSM supplementation (Huhtanen et al. 1985 {1205}; 1989 {1051}; Aronen et al. 1992 {932}; Aronen and Vanhatalo 1992 {948}; Aronen 1991 {991}; Aronen 1990 {1008}). When RSM was compared to other protein sources performance was usually equivalent (SBM, FM)(Grundy et al. 1996 {805}; Pullar 1995 {830}; Varvikko 1987 {1130}) or superior (urea)(Varvikko 1987 {1130}). A response in ADG from RSM supplementation is usually associated with an increase in silage or hay intake increasing the energy supply. The increase in hay intake is usually accounted for by an increased rumen flow rate and increased ADG with a silage diet is due to increased digestion (mainly CP) resulting in an increased feed intake. This may result in an increased amount of AA to the small intestine or improved AA quality (Aronen et al. 1992 {932}; Aronen and Vanhaalo 1992 {948}).

Effect on Carcass Traits

Most studies reported that CM supplementation has little effect on carcass quality on beef steers or bulls (Petit et al. 1994 {862}; Grundy et al. 1996 {805}; Bailey 1989 {1052}; Hakkola 1985 {1180}; Petit and Veira 1994 {853}; Pullar 1995 {830}; Varvikko 1987 {1130}). Mawson et al. (1995 {834}) reported in a review of the literature that there is no published information that suggests GL have caused any deleterious effect on carcass flavor. Conversely, one study reported an off flavor, a sourish, unclear or acrid taste and the complexes held responsible were the phenolic choline esters (Anderson and Sørensen 1985 {1183}). Canola meal supplementation in beef cattle rations has resulted in animal performance that has met or exceeded industry standards (Christensen and McKinnon 1993).