Field peas can be regarded as an acceptable source of protein when properly balanced in the diet with bypass protein sources. Given our present knowledge of ruminant nutrition, peas can safely be fed with minor restrictions. Conservative recommendations generally suggest limiting peas to 15 to 20% of concentrate or 7 to 10% of total mixed ration (TMR) on a dry matter basis. In general, palatability and protein degradability will restrict use without loss of intake, making peas a reasonable substitute for soybean meal or canola meal as a protein source for dairy cows.

The amount of peas used should be governed by the cost of competing protein sources and the cost of providing higher bypass protein supplements for highly productive animals. Minimal processing of field peas is required for animal feeding.

The relatively slow degradation rate of starch in peas may be beneficial in animals fed diets containing a high concentration of grain. No anti-nutritional components are apparent when feeding field peas.

Introduction

Nearly every crop grown for food will have grain deemed unacceptable for its intended use, primarily the result of weather loss, storage, or harvest damage. Livestock provide a source of utilization for salvage crops. In many cases, especially in times of low market prices, peas and many other grain crops have significant added value when included in animal diets.

Compared to soybean meal or canola meal, peas contain approximately half as much crude protein (25.6 vs. 46.3%) lower rumen undegradable protein content (20 vs. 34.6%), and more acid detergent fiber (20.5 vs. 10%) [National Research Council (NRC), 2001]. In addition, peas contain a high level of starch (54%; McLean et al., 1974). This makes peas a unique dual purpose feed, rich in both energy and protein (Table 1). Pea protein is rapidly degraded in the rumen, but the starch is slowly degraded. Therefore, the value of peas differs depending on diet formulation, age of the animal, and type of processing used (Marquardt and Bell, 1988).

Discussion

Composition relative to ruminants

Pea seeds consist of a high quality protein with an average crude protein content between 20 and 25% dry matter DM (Lalles, 1993). Reichert and MacKenzie (1982) reported a considerable range (14 to 28.5% DM cv. Trapper) in protein of feed peas and reported that starch accounted for most of the difference in protein content, while the remainder of variation was due to lipid, neutral detergent fiber (NDF), soluble sugars, and ash. Pea protein is highly soluble at over 70% of crude protein (CP) (National Research Council, 2001); Christensen et al., 2000; Mustafa et al., 1998; Walhain et al., 1992). Pea protein is characterized by a high rumen degradability and a low bypass protein value (20%) (NRC, 2001; Mustafa et al., 1998).

Weaned calves

Peas have been successfully fed to young calves in a University of Alberta study (de Boer et al., 1991; Table 2). The calves averaged 95 days of age and were one to four weeks post-weaning at the onset of the experiment. Average daily gain, dry matter intake of concentrate and hay, and feed conversion efficiency were not different for the control and pea-based concentrates. The results show that peas can be used as a replacement for other protein and barley sources in the diets of young calves. There does not appear to be an upper limit on the amount of peas that can be fed, except within practical ranges of dietary needs and environmental limits.

Unlike the pre-ruminant calf that depends greatly on the type of protein and the quantity and quality of amino acids for growth, the weaned ruminant calf relies more on the introduction of dry feed and the development of a functional rumen (Lalles et al., 1990). Peas can act as the sole protein source for young ruminants that have a functioning rumen with little or no effect on performance. Preweaned and weaned dairy calves were fed a grain starter containing field peas at 40% of the total DM (Marx, 2000). Calves fed the starter with field peas performed similarly to those fed starters with barley or corn (control) grain in the starter rations.

 

Table 1.Typical nutrient analysis of pea seed (Pisum spp.) for dairy cattle (NRC Dairy Nutrient Requirements, 1989 and 2001).
TDN, %	87.0
Digestible Energy, Mcal/kg (Mcal/lb)	1.74 (0.79)
Metabolizable Energy, Mcal/kg (Mcal/lb)	1.55 (0.70)
Net Energy for Maintenance, Mcal/kg (Mcal/lb)	0.98 (0.44)
Net Energy for Growth, Mcal/kg (Mcal/lb)	0.67 (0.30)
Net Energy for Lactation, Mcal/kg (Mcal/lb)	0.91 (0.41)
Crude Protein, %	25.6
Rumen Degraded Protein, % of CP	~ 78.0
Rumen Undegraded Protein, % of CP	~ 22.0
Ash, %	3.7
Lipids, %	1.5
Fiber, %	6.7
Soluble Crude Fiber, %a	0.0
Starch, %	~ 54.0
Sugar, %	6.5
Cystine, % of CP	1.42
Histidine, % of CP	2.59
Isoleucine, % of CP	4.09
Leucine, % of CP	7.24
Lysine, % of CP	7.17
Methionine, % of CP	1.00
Phenylalainine, % of CP	3.83
Tryptophan, % of CP	0.90
Threonine, % of CP	3.75
Valine, % of CP	4.67
a The neutral detergent fiber content of peas, which approximates the sum of hemicellulose, cellulose, and lignin present in the cell wall, was negatively correlated with the content of pea protein (Reichert and MacKenzie, 1982). Because the majority of fiber exists in the form of hemicellulose and cellulose with very little lignin, the fiber is considered highly digestible.

 

Table 2.Effect of feeding peas on Holstein calf performance (de Boer et al., 1991).
Item	Control	Peas	Hay
Ingredients
Barley, %	57.2	23.8	—
Peas, %	—	50.0	—
Wheat Shorts, %	15.0	15.0	—
Canola Meal, %	10.2	2.0	—
Soybean Meal - 48, %	10.2	2.0	—
Meat and Bone Meal, %	1.0	1.0	—
Molasses, %	3.0	3.0	—
Other, %	3.4	3.2	—
Nutrients
Dry Matter, %	84.5	83.5	87.5
Organic Matter, % DM	92.3	93.5	93.8
Crude Protein, % DM	20.1	20.2	13.2
NDF, % DM	21.0	18.4	67.9
ADF, % DM	7.1	7.0	38.9
Starch, % DM	46.6	46.4	6.0
Performance
Initial Body Wt, lb	154.0	147.0	—
Average Dairy Gain, lb	1.81	1.74	—
Dry Matter Intake, lb/da
Concentrate	3.68	3.59	—
Hay	2.40	1.90	—
Total	6.08	5.49	—
Feed/Gain, lb DM/lb	3.36	3.15	—

Lactating cows

Intake: Dry matter intake of oat hay and grain by four lactating Friesian cows was significantly higher when cows were given peas rather than barley grain (19 vs. 14.5 lb/ d) (Valentine and Bartsch, 1987).

Milk Yield: There have been few studies on the effect of feeding peas to lactating dairy cattle and the results vary. Due to the lower effective degradability of crude protein in peas compared to soybean meal (12 vs. 28 RDP, % of DM) (Khorasani et al., 1992) and a lower undegradable protein content relative to soybean meal (22 vs. 35%), milk production may decrease in early lactation when the demand for rumen undegradable protein is high (Corbett et al., 1995). In some studies this finding has been confirmed, and the reduction in milk production is attributed to the greater degradation of pea protein in the rumen (Khasan et al., 1989). Results from feeding peas to a high-producing Holstein dairy herd (averaging 68.9 lbs per day) are shown in Table 3 (Corbett et al., 1995).

It is noteworthy that no differences were found in milk production for second lactation and older cows, while first lactation cows produced 17% less milk when given the diet which included field peas. Since the diets were equal for energy (NE_L) and protein, the requirement for growth among the younger first-calf cows may have precluded the availability of those nutrients for milk production. When actual milk yield was adjusted to fat-corrected milk (FCM) for 4% fat, there was no difference in FCM yield. Milk fat percentage was higher in early-, mid-, and late-lactation cows fed peas.

The need for bypass protein is greatest during early lactation and declines as lactation progresses. Pea protein has been successfully substituted for soybean protein in late lactation cows in a study conducted at the University of Alberta (Khorasani et al., 1992). The soybean meal diet was formulated to satisfy the nutrient requirements of a Holstein cow weighing 1,300 lbs and producing 50 lbs of 3.5% fat milk at 200 days in lactation. A total mixed ration (TMR) consisting of 25% alfalfa silage, 25% brome grass silage, and 50% concentrate was fed ad libitum twice daily. Four different 18.6% crude protein concentrates were used in which pea protein replaced soybean protein at 0, 33, 67, and 100%, with barley as the major grain source. Daily milk production, 4% fat corrected milk (FCM) production and dry matter intake were not affected as the level of peas was increased (Table 4).

A field trial was initiated in Alberta in a high producing herd to see if practical rations could be formulated using peas as a protein source while maintaining peak milk yield as well as average production (Corbett et al., 1994). Two 18.5% crude protein concentrates were formulated to contain similar amounts of bypass protein using meat meal and distillers grains. Soybean meal and canola meal were used in the control ration while the treatment ration concentrate contained 25% peas.

The concentrates were fed through a computer controlled feeder according to level of milk production. A 50% alfalfa silage, 50% whole plant barley silage mixture was fed free choice along with 5 lbs of alfalfa hay per cow daily. Milk yield ranged between 70 and 75 lbs for the six-month duration of the experiment. Milk yield peaked at approximately 60 days and did not differ between the two concentrate groups. Persistency of milk production was not affected by concentrate source and there was a tendency for higher butterfat content in the milk of animals fed peas. The results of this trial indicate that peas can be fed to high producing animals when fed properly balanced rations. The use of peas would be limited only by the cost of providing adequate bypass protein.

 

Table 3.Chemical composition of concentrate mixtures and milk production and composition of cows fed pea or SBM/CM supplemented diets (Corbett et al., 1995).
Chemical Composition	SBM/CM Based	Pea Based
DM %	89.8	89.7
	— (% of DM) —
Crude Protein	18.5	18.5
Acid Detergent Fiber	7.3	7.4
Neutral Detergent Fiber	13.4	13.6
Crude Fat	5.2	4.5
Net Energy for Lactation, Mcal/lb	0.80	0.80
Performance of all cows (n = 155, 108, and 109 for cows in early, mid- and late-lactation, respectively).
Production
	—— (lbs/day) ——
Milk	70.6a	67.2b
Fat	2.14a	2.27b
Protein	2.12	2.07
FCM	60.4	61.3
Milk Composition
	——— (%) ———
Fat	3.13a	3.47b
Protein	2.99	3.10
ab Means in the same row with different letters are different (P<0.05)

 

Table 4. Effect of substitution of pea protein for soybean meal protein on milk production and dry matter intake in late lactation dairy cows (Khorasani et al., 1992).
	Pea Protein %
Performance	0	33	67	100
Milk Yield, lbs/day	45.5	48.4	47.1	47.7
4% FCM, lbs/day	44.4	48.0	48.2	45.5
Dry Matter Intake, lbs/day	46.6	47.3	48.2	47.5

Milk Composition: Milk fat percentage was higher (P<0.05) in cows fed a pea concentrate in all stages of lactation compared to cows fed a soy/canola concentrate (Corbett et al., 1995). This was attributed to the low degradation rate of non-structured carbohydrates in peas. Previous reports suggest this prevents a depression in rumen pH (Valentine and Bartsch, 1987). This maintains a more stable rumen, resulting in increased fiber digestion and a higher acetate:propionate ratio, leading to an increase in milkfat (Valentine and Bartsch, 1987). Robinson and McQueen (1989) reported low pea starch degradation rate of 3.9 to 5.3% per hour compared to barley starch (21.3 to 34.2% per hour) when peas were fed in a high concentrate:low forage diet. However, the University of Saskatchewan trials reported similar milkfat percentage and yield in dairy cattle fed soybean meal, micronized or raw peas (Christensen et al., 1998).

Protein: Milk protein percentage and yield were not affected by diet at any stage of lactation when peas were substituted for soy/canola meal in the concentrate and the diets were balanced for undegradable protein (Corbett et al., 1995). Because the concentrate portions of the diets were formulated to contain similar levels of undegradable protein, lack of differences in milk protein percentage and yield could be a reflection of a similar amino acid profile and supply to the small intestine of cows fed either peas or soy/canola meal. However, the formulation of the soy/canola meal and pea concentrate portions of the diet that contained equal amounts of undegradable protein could have masked any potential of the diets to influence milk protein percentage and yield.

Effects on the rumen

pH: Peas may support better production for cows fed hay-based diets by promoting a more stable rumen environment. Supplementing hay diets with high levels of barley grain in dairy cow diets causes major changes in ruminal fermentation. This leads to digestive disorders, reductions in hay intake, and losses in milk production due to the rapid fermentation of starch to volatile fatty acids and lactic acid. The result is a low rumen pH (below 5.8) and a severe inhibition of fiber digestion. Rumen bacteria normally associated with fiber digestion are almost eliminated when this occurs (Valentine and Bartsch, 1987; Bartsch and Valentine, 1986). Replacement of barley with peas (and other legumes) as 70% of the total ration fed twice daily to cows resulted in a ruminal pH that was significantly higher three to six hours after feeding. Ruminal pH did not fall below 6.0 in contrast to barley fed cows. When barley was supplemented, the rumen pH was below 6.0 for approximately seven hours of the 12-hour feeding period (Bartsch and Valentine, 1986).

Ammonia-Nitrogen Concentrations: Ammonia-nitrogen concentration in the rumen of the cows offered hammer-milled barley grain with 2% urea was below 5 mg per 100 ml for seven hours of the 12-hour feeding interval. Replacing barley with legume grains (including peas) resulted in higher ammonia-nitrogen concentrations from 0 to eight hours after feeding. Rumen ammonia-nitrogen concentrations below 5 mg per 100 ml are sub-optimal for maximum bacterial efficiency by the less competitive cellulolytic bacteria (Valentine and Bartsch, 1987).

Rumen degradability

Protein: Peas, like other legume seeds, are characterized by their highly degradable protein and slowly degradable starch. Much of the protein in peas is digested by ruminant animals. Pea protein is highly soluble with a low rumen escape or bypass protein content. NRC (1989) assigns a bypass protein content of 22%, based on four measurements. Peas contain approximately 40% soluble protein (Aguilera et al., 1992). Since pea protein is completely degraded by ruminants, this suggests that the non-soluble, slowly degradable fraction is about 38%. The initial degradation rate of the slowly degradable protein fraction appears to be much slower than for soybean meal (Aguilera et al., 1992). The pea protein disappearance rate was approximately 1.6% per hour compared to 4.5% for soybean meal after six hours of rumen incubation time. This relatively slow rate of degradation has been observed in other studies (Lindberg, 1981). Degradation rate from six to 12 hours appears to be similar to soybean meal. This may be advantageous in providing a more sustained release of nitrogen needed for rumen microbial growth.

Peas have been successfully substituted for soybean meal in situations where the need for undegradable protein has been modest, such as in late-lactation cows (Khorasani et al., 1992) and in a commercial dairy herd with modest milk production of 51 pounds per day (Ward et al., 1989). Alberta researchers (Corbett et al., 1995) studied the effects of substituting peas for a combined soybean meal (SBM) and canola meal (CM) supplement on milk producing dairy cows.

Two 18.5% crude protein grain concentrate diets were formulated based on the nutrient analyses of the forages available. The control grain mix contained standard protein sources, principally SBM/CM, while the test grain mix was formulated to contain approximately 25% field peas as the major source of protein. Both grain rations were formulated to the same nutrient specifications and balanced for undegradable protein (NRC, 1989). The duration of the trial was six months, during which grain feeding levels were adjusted monthly based on milk yield. For cows in early lactation, 4% fat-corrected milk yield was higher for cows fed pea-based concentrates (69 lb/d) than for cows fed SBM/CM supplement (65.5 lb/d). Fat-corrected milk yield was not different for cows fed SBM/CM compared with cows fed the pea supplement when cows across all stages of lactation were included in the analyses. Milk fat percent was significantly higher for early- and mid-lactation cows fed the pea supplement. These results suggest that peas can be substituted for SBM/CM as a protein source for high-producing dairy cows.

In situ research at North Dakota State University by M.L. Bauer and G.P. Lardy (Table 5, unpublished data) on four cultivars of field peas grown in North Dakota (Trapper, Profi, Carneval, and Arvika) was conducted to determine rumen degradable protein. Crude protein values for the four cultivars ranged from 19.4 to 26.1% on a DM basis. Nutrient Requirements for Dairy Cattle (NRC, 2001) shows N disappearance (A fraction) for raw field peas at 55.5%. All the cultivars used in this study were similar with the exception of Trapper. Trapper, however, had the most rapid degradation rate (16.3%/h), resulting in similar rumen degradable protein frations.

Starch: The energy content of field peas is similar to corn and wheat. The starch content of peas ranges from 41 to 54% of the dry matter. The rumen degradable fraction is characterized by a slow degradation rate (Walhain et al., 1992; Robinson and McQueen, 1989). In high concentrate diets the ruminal degradation rate of pea starch is similar to corn and much slower than wheat, oats, or barley (Table 6). A slow starch degradation rate would help control rumen pH, especially in animals that are fed large amounts of grain. Fiber digestion is depressed at a rumen pH below 6.0, which contributes to reduced dry matter intake, butterfat depression, and increased digestive disturbances. This may also explain why high producing cows fed high grain diets tended to have higher butterfat percentage in their milk when peas comprised a significant proportion of the concentrate (Corbett et al., 1994).

 

Table 5.In situ rumen nitrogen degradation of field pea cultivars.
	Variety
Item	Profi	Arvika	Carneval	Trapper	SEM
CP, % DM	22.6	26.1	22.6	19.4	—
N disappearance at 0 hour, %	58.4	56.5	53.3	40.2	7.0
Rate of CP digestion, % / hour	10.8bc	7.3b	15.4bc	16.3c	2.9
Rumen degradable protein a, % of CP	82.2	76.9	83.5	79.0	4.8
Rumen undegradable protein a, % of CP	17.8	23.1	16.5	21.0	—
a Passage rate of undegraded protein 8%/hr (Mathers and Miller, 1981). bc Within a row, means without a common superscript letter differ (P < 0.10).

     

Table 6.Ruminal degradability characteristics of starches from selected feed ingredients (Robinson and McQueen, 1989).
		Rumen Degradation Rate (%/hour)
		b Hay: a Conc	a Hay: b Conc
	Total Starch		Slow	Fast
	(% DM)
Barley	56.1	22.4	21.3	34.2
Oats	61.6	14.2	14.6	22.6
Corn	67.6	3.5	2.7	8.2
Wheat	66.6	22.6	17.2	23.2
Peas	41.8	13.4	3.9	5.3

Processing

Little research has been reported in the scientific literature on the influence of processing on the nutritive quality of peas for ruminant animals. Given the large kernel size of peas, it is questionable whether peas require processing before being fed. In spite of this lack of information, it would seem reasonable that peas be processed and that processing methods which minimize particle size reduction be used. Coarse grinding or rolling are the most common processing methods currently employed.

Inclusion of peas in pelleted concentrates generally improves pellet quality, resulting in more durable pellets with less fines produced with mechanical handling (de Boer et al., 1991). Steam flaking of peas has been shown to have no effect on degradability of protein or on gelatinization of starch.

Anti-nutritional factors

While it is not clear how high levels of field peas will affect milk yield and milk composition, current knowledge of ruminant nutrition suggests that peas can safely be fed with minor restrictions (Bond et al, 1989; Saini et al, 1989). Conservative recommendations generally suggest limiting peas to 15 to 20% of concentrate or 7 to 10% of a total mixed ration on a dry matter basis. The amount of peas used should be governed by the cost of competing protein sources and the cost of providing higher bypass protein supplements for highly productive animals.

Literature Cited

Aguilera, J.F., M. Bustos, and E. Molina. 1992. The degradability of legume seed meals in the rumen: Effect of heat treatment. Anim. Feed Sci. Tech. 36:101-112.

Bartsch, B.D. and S.C. Valentine. 1986. Grain legumes in dairy cow nutrition. Proc. Aust. Soc. of An. Prod. 16:32-34.

Bock, E.J., M.L. Bauer, G.P. Lardy, and T.C. Gilberry, 2000. Effects of processing field peas Pisum sativum in steer grower diets. J. Anim. Sci. 73(Supp.2):88.

Bond, D.A., D.B. Smith, J. Huisman, T.F.B. van-der Poel, and I.E. Liener. 1989. Possibilities for the reduction of antinutritional factors in grain legumes by breeding. Proc. 1^st Int. Workshop on Antinutritional Factors (ANF) in Legume Seeds. Nov. 23-25, 1988. Wageningen, Netherlands. pp. 285-296.

Corbett, R.R., E.K. Okine, and L.A. Goonewardene. 1995. Effects of feeding peas to high-producing dairy cows. Can. J. of An. Sci. 75(4):625-629.

Corbett, R.R., E.K. Okine, L. Goonewardene, J. Byer, L.S. Doepel, and R. Douglas. 1994. Feeding field peas to high producing dairy herds. Farming for the future. Project number #91-F004-4, Alberta Agriculture, Food and Rural Development, Edmonton, AB, Canada. pp.16-20.

Christensen, D.A. and A. Mustafa. 2000. The use of peas in dairy rations. Ad. Dairy Tech. 12:293-302.

de Boer, G., R.R. Corbett, and J.J. Kennelly. 1991. Inclusion of peas in concentrates for young calves. 70^th Annual Feeders Day Report, University of Alberta. pp. 41.

Focant, M., A. VanHoecke, and M. Vanbelle. 1990. The effect of two heat treatments (steam flaking and extrusion) on the digestion of Pisum sativum in the stomachs of heifers. Anim. Feed Sci. Tech. 28:303-313.

Khasan, A.M., T.K. Tashev, N.A. Todorov, and A.M. Hasan. 1989. Lucerne haylage, sunflower meal and peas as protein feeds in diets for dairy cows. Zhivotnov dni-Nauki 26(3):30-36.

Khorasani, G.R., E.K. Okine, R.R. Corbett, and J.J. Kennelly. 1992. Peas for dairy cattle. 71^st Annual Feeders Day Report, Animal Science Department, University of Alberta, Edmonton, AB. pp. 28.

Lalles, J.P. 1993. Nutritional and anti-nutritional aspects of soyabean and field pea proteins used in veal calf production: A review. Livestock Prod. Sci. 34:3-4.

Lalles, J.P., R. Toullec, P. Patureau-Mirand, and C. Poncet. 1990. Changes in ruminal and intestinal digestion during and after weaning in dairy calves fed concentrate diets containing pea or soya bean meal. 2. Amino acid composition and flow of duodenal and ileal digesta, and blood levels of free amino acids. Livestock Prod. Sci. 24(2):143-159.

Lindberg, J.E. 1981. The effect of basal diet on the ruminal degradation of dry matter, nitrogenous compounds and cell walls in nylon bags. Swedish J. Agric. Res. 11:159-169.

Marquardt, R.R. and J.M. Bell. 1988. Future potential of pulses for use in animal feeds. In World Crops: Cool Season Food Legumes. R.J. Summerfield, Ed. pp. 421-444.

Marx, G.D. 2000. Dry field peas in grain starter rations for preweaned and weaned dairy calves. J. Dairy Sci. 83:260 (Suppl. 1).

McLean, L.A., F.W. Sosulski, and C.G. Youngs. 1974. Effect of nitrogen and moisture on yield and protein in field peas. Can. J. Plant Sci. 54:301-305.

Mustafa, A.F., D.A. Christensen, J.J. McKinnon. 1998. Effects of moist heat treatment on crude protein composition and degradability of field peas. Can. J. An. Sci. 78(3):453-456.

National Research Council. 1989. Nutrient Requirements of Dairy Cattle. 6^th Rev. Ed. National Academy Press, Washington, DC.

National Research Council. 2001. Nutrient Requirements of Dairy Cattle. 6^th Ed. National Academy Press, Washington, DC.

Reichert, R.D. and S.L. MacKenzie. 1982. Composition of peas (Pisum sativum) varying widely in protein content. J. of Agric. Food Chem. 30(2):312-317.

Robinson, P.H. and R.E. McQueen. 1989. Non-structural carbohydrates in rations for dairy cattle. Proc. West. Can. Dairy Sem. pp. 153-167.

Saini, H.S., J. Huisman, T.F.B. vanderPoel, and I.E. Liener, Ed. 1989. Legume seed oligosaccharides. In Recent Advances of Research in Antinutritional Factors in Legume Seeds. Proc. of 1^st International Workshop on "Antinutritional Factors (ANF) in Legume Seeds," Nov. 23-25, 1988, Wageningen, Netherlands. pp. 329-341.

Valentine, S.C. and B.D. Bartsch. 1987. Fermentation of hammermilled barley, lupin, pea and faba bean grain in the rumen of dairy cows. Anim. Feed Sci. Tech. 16(4):261-271.

Walhain, P., M. Foucant, A. Thewis. 1992. Influence of extrusion on ruminal and intestinal disappearance in sacco of pea (Pisum sativum) proteins and starch. Anim. Feed Sci. Tech. 38(1):43-55.

Ward, D. R.R. Corbett, W. Slack, and
L. Goonewardene. 1989. Field Peas as a Protein Source for Lactating Dairy Cows. Final report for Farming for the Future, Project number 89-F023-5. Alberta Agriculture, Food and Rural Development, Edmonton, AB, Canada.

Acknowledgements

Gratitude is extended to the peer reviewers of this document:

Dr. Marc L. Bauer, Assistant Professor, Ruminant Nutrition, North Dakota State University, Animal and Range Sciences, Hultz Hall, P.O. Box 5727, Fargo, ND 58105.

Dr. George D. Marx, Professor, Animal Science (Dairy), University of Minnesota, Northwest Research and Outreach Center, 2900 University Ave., Crookston, MN 56716.

EB-76, May 2002

• Introduction to Field Pea Blaine Schatz
• Field Pea in Beef Cattle Diets Vern Anderson
• Field Pea in Swine Diets Doug Landblom
• Field Pea in Sheep Diets G.P. Lardy, M.L. Bauer, E.R. Loe
• Field Pea in Poultry Diets R.L. Harrold