Vern Anderson and Jon Schoonmaker
Field peas are marketed as dry, shelled products primarily for human
consumption. Surplus grain, off quality grains, and screenings which contain
high levels of protein (approximately 24% CP) and energy (approximately 48%
starch), are an attractive, nutrient dense livestock feed. Significant amounts
of pulse grains are produced annually in the northern Great Plains of the
One hundred twenty-seven crossbred heifers (approximately 799.9 ± 11.4
lbs.) were allotted by weight to one of three pea-supplemented diets (4 pens
per treatment, 10 or 11 head per pen) to determine the optimum level of pea
processing needed to maximize cattle performance. Steers were housed and fed at
Cattle were vaccinated for protection against IBR, BVD, BRSV, PI3
Cattle were slaughtered at Tyson Foods (
Data were subjected to a one-way analysis of variance as a completely
randomized design using the GLM procedures of SAS (Version 8.0; SAS Inst. Inc.,
Particle size of ground, rolled, and whole peas was 701, 3100, and 9250 microns, respectively. Dry matter intake was greatest (P<.05) for the rolled-pea treatment (22.81 lbs. per hd/day) for the entire feeding period (Table 2) compared to ground (21.21 lbs.) and whole (21.33 lbs.). Intake exhibited a quadratic response (P<.05) to processing treatment during each of the three feeding periods with reduced intake for the ground- and whole-pea treatments. Average daily gains were also greatest (P<.01) for the rolled- pea treatment for the entire feeding period (3.39 lbs./hd/day) compared to ground (3.12 lbs.) and whole (2.96 lbs.). Statistical differences in gain were greater during period 1 (P<.01) and period 2 (P<.06) than period 3 (P<.15). Feed efficiency expressed as feed per gain or gain per feed (Table 2) was not different during any of the feeding periods or overall (P>.16).
Carcass data followed the pattern of rate of gain and final weight with predictable numerical differences observed. Hot carcass weight (P<.13) and yield grade (P<.10) showed the greatest response to treatment with higher values for the rolled-pea treatment. (Table 3).
Bock (2000) reported that when peas were fed at 40% of the diet DM in a forage-based diet, cattle fed dry-rolled peas gained the least compared to cattle fed ground and whole peas in a Calan headgate study with seven individually fed animals per treatment. Birkelo et al. (2000) reported no statistical differences from rolled or whole peas in finishing diets when peas were included at 10% of the diet DM. Pea-fed steers grew faster than non-pea-fed steers through 56 days on feed, but gained slower from day 57 to slaughter. Intake did not differ among treatments. Pea-fed steers were more efficient than non-pea-fed steers the first half of the trial, but feed efficiency did not differ during the second half of the trial.
Dry rolling has a tendency to split the peas into a lighter and fluffier hull fraction and a heavier endosperm fraction. The lighter particles may not mix well and could add variation to the diet. It may be possible that separation of the hull from the endosperm is more of a problem in diets where peas are included at a high level. When fed at 28% of the diet DM, as in this trial, separation of the hull and endosperm in the dry-rolled treatment does not appear to be a problem.
The optimum level of field pea inclusion in feedlot diets is not clear. Flatt and Stanton observed a linear decrease in intake and linear improvement in feed efficiency as level of pea inclusion increased from 0 to 20% of diet DM, but saw no effect on gain. In contrast, Fendrick et al. (2004) demonstrated that DM intake increased up to 40% peas, then decreased when the pea level was increased to 59% of the diet DM but gain did not differ due to level of peas. Fendrick et al., (2005) also observed coarse-rolled peas or whole peas fed at 15 or 30% of dry matter intake in a finishing ration replacing corn did not affect performance or carcass traits (P>.10).
Results appear to be mixed for the few studies addressing processing options for peas in feedlot diets. Intake in the study reported here was greatest for cattle fed rolled peas indicating that rumen status from finely ground peas and digestibility of whole peas may be issues for further study. The cud chewing associated with high forage diets may contribute to particle size reduction of whole peas.
The cost of processing is a consideration if special accommodations are required for rolling peas. Purchasing field pea splits or screenings may be the least costly method of processing peas but the buyer has little control of particle size.
Note: Appreciation is expressed to George Brown for his cooperation in this study by providing feeder heifers. The cattle were fed on a custom basis with the owner billed for normal commercial yardage rates and feed costs.
Birkelo, C. P., B. J. Johnson, and B. D. Rops. 2000. Field peas in finishing cattle diets and the effect of processing. SDAES Cattle 00-4. South Dakota State Univ. Extension Service, Brookings.
Bock, E. J. 2000. Effects of processing field peas in steer grower diets. Pages 29 – 31 in Carrington Research Extension Center Beef Production Field Day Report. Vol. 23. North Dakota State Univ., Fargo.
Fendrick, E. M.,
I. G. Rush, D. R. Brink, G. E. Erickson,
Fendrick, E. M.,
I. G. Rush, D. R. Brink, G. E. Erickson,
Flatt, W. R., and
T. L. Stanton. 2000. Effect of Profi peas, Pisum arvense, on growth performance
and carcass characteristics of feedlot cattle. Pages 81 – 84 in Colorado State
Univ. Anim. Sci. Research Report.
material is based upon work supported by the