Field pea production in North Dakota is increasing as growers realize the agronomic benefits of field peas as a legumious crop in rotation systems. Field peas are grown primarily for the human food market, but surplus grain or grain which does not make human food grades can and is used in livestock rations. Field pea grain is high in crude protein (CP) (Table 1) and high in rumen degradable protein (NRC, 1989). The starch content is 54% (McLean et al., 1974) and the net energy for gain (NE_g) is 0.67 Mcal/lb (NRC, 1989).

Previous research has focused on using field pea as a protein source in diets for nonruminants (Gatel, 1994) and dairy cattle (Corbett et al., 1995). Field pea has been shown to be an effective replacement for SBM (Corbett et al., 1995; Khorasani et al., 1992) and SBM and canola meal combinations (Petit et al., 1997) in diets fed to lactating dairy cows. Optimum inclusion level of field pea in nonruminant diets have been suggested to be 25.0 to 33.3% (Castanon and Perez-Lanzac, 1990; Perez-Maldonado et al., 1999; and Farrell et al., 1999). Energy values for field pea fed in a growing ration to beef cattle suggest that field pea has a NE_g of 0.71 Mcal/lb (calculated from Bock et al., 2000).

Three studies have been conducted at North Dakota State University using field peas in sheep diets. All three research projects have focused on the use of field peas in diets for growing and finishing lambs.

Experiment One

One hundred Columbia crossed lambs (74.7 ± 2.9 lb initial body weight, BW) were fed for 89 days to evaluate the energy value and optimal inclusion level of field peas in diets fed to feedlot lambs (Loe et al., 2001). Four dietary treatments were fed where dry-rolled field pea (cv. Profi) replaced dry-rolled corn (DRC) at 0, 15, 30, or 45% of the diet on a dry matter (DM) basis. Diets contained 75% DRC or field pea, 10% alfalfa hay, 5% concentrated separator by-product (CSB), and 10% supplement. Field pea was cracked in half by processing through a single stage roller mill. Diets were formulated to contain a minimum 15% CP, 0.7% Ca, 0.36% P, 1.22% K, 1.74 Ca:P, and 12 mg/lb lasalocid. Performance data is reported in Table 1. Calculated net energy values are presented in Table 2.

Table 1.Effect of treatment on feedlot performance in Experiment 1.
	Field pea in diet, % DMbasis					Contrast
Item	0	15	30	45	SEMa	Linear	Quadratic	Cubic
Weight, lb
Initial	73.9	75.6	72.3	77.2	2.87	0.61b	0.56	0.33
Final	135.2	141.8	138.3	144.9	3.53	0.14	0.99	0.24
Dry matter intake
lb/day	3.51	3.66	3.42	3.57	0.07	0.97	0.99	0.02
% of BW	3.35	3.36	3.26	3.23	0.07	0.15	0.81	0.51
ADG, lb	0.68	0.75	0.75	0.75	0.04	0.25	0.63	0.65
Gain:Feed, lb/lb	0.197	0.205	0.218	0.213	0.010	0.22	0.52	0.63
a n = 5. b Probability of greater F.

Experiment Two

One hundred Columbia crossed ram lambs (86.2 ± 0.5 lb initial BW) were blocked by weight and allotted randomly to dietary treatment (five pens/treatment and four lambs/pen; Loe et al., 2001). Lambs were fed for 63 days to evaluate the energy value and optimal inclusion level of field pea in lamb finishing diets. Dietary ingredients and nutrient composition were similar to Exp. 1; however, an additional treatment was added where dry-rolled field pea replaced DRC and all SBM (45_SBM). This diet was added to evaluate if RDP was overfed in the 45% field pea diet, limiting performance. Performance data is reported in Table 3. Calculated net energy values are presented in Table 4.

        

Table 2.Effect of treatment on dietary net energy in Experiment 1.
	Field peas, % DM basis					Contrast
Item	0	15	30	45	SEMa	Linear	Quadratic	Cubic
NEmb, Mcal/lb	0.94	0.98	1.01	1.02	0.03	0.10c	0.73	0.95
NEgd, Mcal/lb	0.63	0.67	0.70	0.69	0.03	0.10	0.69	0.90
a n = 5. b Net energy for maintenance. c Probability of greater F. d Net energy for gain.

 

Table 3.Effect of treatment on feedlot performance in Experiment 2.
	Field peas, % DM basis						Contrast
				————45————
Item	0	15	30	+SBM	-SBM	SEMa	Lin	Quad	Cub	± SBM
Weight, lb
Initial	86.2	87.8	86.2	86.2	86.0	0.44	0.98b	0.73	0.66	0.81
Final	135.2	137.4	137.2	133.2	137.2	2.01	0.50	0.14	0.93	0.18
Dry matter intake
lb/day	3.48	3.66	3.46	3.48	3.44	0.11	0.52	0.28	0.86	0.86
% of BW	3.19	3.28	3.12	3.17	3.10	0.09	0.76	0.26	0.61	0.61
ADG, lb	0.78	0.81	0.81	0.74	0.83	0.031	0.49	0.15	0.85	0.15
Gain:Feed, lb/lb	0.223	0.223	0.233	0.217	0.237	0.008	0.82	0.35	0.32	0.10
a n = 5. b Probability of greater F.

 

Table 4. Effect of treatment on dietary net energy in Experiment 2.
	Field peas, % DM basis						Contrast
				————45————
Item	0	15	30	+SBM	-SBM	SEMa	Lin	Quad	Cub	± SBM
NEmb, Mcal/lb	1.05	1.04	1.09	1.01	1.10	0.03	0.63c	0.25	0.24	0.05
NEgd, Mcal/lb	0.73	0.73	0.77	0.70	0.78	0.03	0.62	0.24	0.24	0.05
a n = 5. b Net energy for maintenance. c Probability of greater F. d Net energy for gain.

Experiment Three

Two hundred and forty lambs (wethers and ewes) were used to evaluate the use field peas as a replacement for soybean meal and barley in lamb diets (Poland and Faller, 1998). Lambs were allotted by weight and sex into eight pens (2 pens/treatment). The control diet contained 81% concentrate (72.6% barley and 8.4% soybean meal). Peas replaced barley and soybean meal in incremental levels at 0, 8.8, 17.7, and 26.5% peas were included in the diets (DM basis). Lambs were fed of 90 days. Performance data is reported in Table 5.

 

Table 5.Effect of treatment on feedlot performance in Experiment 3.
	Field pea in diet, % DM basis
Item	0	8.8	17.7	26.5	SEM
Weight, lb
Initial	75.4	71.2	72.3	72.1	0.93
Final	104.3	107.6	110.0	111.6	6.53
Dry matter intake,
lb/day	3.57	3.73	3.70	3.74	0.05
ADG, lb	0.33	0.40	0.42	0.44	0.07
Gain:Feed, lb/lb	0.092	0.109	0.113	0.119	0.015

Results and Recommendations

Peas appear to have a net energy value at least equal to corn in most research conducted in North Dakota. Based on lamb performance (Exp. 1) there was a linear (P = 0.10) increase in dietary net energy. In Exp. 2, no difference in dietary net energy occurred with increasing level of field pea. Dietary net energy was greater for 45% -SBM compared with 45% +SBM. Average calculated NE_m and NE_g for field pea were 1.25 and 0.92 Mcal/lb, which was 14% greater than corn. Field pea is a suitable replacement for corn in lamb finishing diets.

Peas appear to be an excellent source of energy, protein, and other nutrients. Use in sheep diets is likely dictated by cost of nutrients in other available feedstuffs. To our knowledge no research has investigated the use of field peas in diets for gestating or lactating ewes. However, based on these data sets in growing and finishing lambs, and data generated in other species, no problems would be anticipated with their use in ewe diets.

Literature Cited

Bock, E.J., Bauer, M.L., Lardy, G.P. , Gilbery, T.C., 2000. Effects of processing field peas (Pisum sativum) in steer growing diets. J. Anim. Sci. 78(Suppl. 2), 88 (Abstr.).

Castanon, J.I.R., Perez-Lanzac, J., 1990. Substitution of fixed amounts of soyabean meal for field beans (Vicia faba), sweet lupins (Lupinus albus), cull peas (Pisum sativum), and vetchs (Vicia sativa) in diets for high performance laying leghorn hens. Br. Poultry Sci. 31, 173-180.

Corbett, R.R., Okine, E.K., Goonewardene, L.A., 1995. Effects of feeding peas to high-producing dairy cows. Can. J. Anim. Sci. 75, 625-629.

Farrell, D.J., Perez-Maldonado, R.A., Mannon, P.F., 1999. Optimum inclusion of field peas, faba beans, chick peas and sweet lupins in poultry diets. II. Broiler experiments. Brit. Poult. Sci. 40, 674:680.

Khorasani, G.R., Okine, E., Corbett, R., Kennelly, J.J., 1992. Effect of substitution of peas for soybean meal on milk production of mid-lactating dairy cows. Can. J. Anim. Sci. 72, 1000 (Abstr.).

E.R. Loe, M.L. Bauer, G.P. Lardy, J.S. Caton, and P.T. Berg. 2001. Field pea (Pisum sativum) inclusion in corn-based lamb finishing diets. Submitted to Small Rum. Res.

NRC, 1989. Nutrient requirement of dairy cattle, 6th edn. National Academy Press, Washington, DC.

Petit, H.V., Rioux, R., Ouelett, D.R., 1997. Milk production and intake of lactating cows fed raw or extruded peas. J. Dairy Sci. 80, 3377-3385.

Poland, W.W. and T.C. Faller. 1998. Field pea as a feedstuff for growing lambs. Proc. Western Dakota Sheep Day. Rep. # 39. pp. 16-20.

EB-76, May 2002

• Introduction to Field Pea Blaine Schatz
• Field Pea in Beef Cattle Diets Vern Anderson
• Field Peas in Dairy Cattle Diets J.W. Schroeder
• Field Pea in Swine Diets Doug Landblom
• Field Pea in Poultry Diets R.L. Harrold