Effect of field pea level on intake, digestion, microbial efficiency, ruminal fermentation, and in situ disappearance in beef steers fed forage-based diets

Abstract

Four ruminally and duodenally cannulated crossbred beef steers (397+/-55 kg initial BW) were used in a 4 x 4 Latin square to evaluate the effects of increasing level of field pea supplementation on intake, digestion, microbial efficiency, ruminal fermentation, and in situ disappearance in steers fed moderate-quality (8.0% CP, DM basis) grass hay. Basal diets, offered ad libitum twice daily, consisted of chopped (15.2-cm screen) grass hay. Supplements were 0, 0.81, 1.62, and 2.43 kg (DM basis) per steer daily of rolled field pea (23.4% CP, DM basis) offered in equal proportions twice daily. Steers were adapted to diets on d 1 to 9; on d 10 to 14, DMI were measured. Field pea and grass hay were incubated in situ, beginning on d 10, for 0, 2, 4, 8, 12, 16, 24, 36, 48, 72, and 96 h. Ruminal fluid was collected and pH recorded at -2, 0, 2, 4, 6, 8, 10, and 12 h after feeding on d 13. Duodenal samples were taken for three consecutive days beginning on d 10 in a manner that allowed for a collection to take place every other hour over a 24-h period. Linear, quadratic, and cubic contrasts were used to evaluate the effects of increasing field pea level. Total DMI and OMI increased quadratically (P = 0.09), whereas forage DMI decreased quadratically (P = 0.09) with increasing field pea supplementation. There was a cubic effect (P < 0.001) for ruminal pH. Ruminal (P = 0.02) and apparent total-tract (P = 0.09) NDF disappearance decreased linearly with increasing field pea supplementation. Total ruminal VFA concentrations responded cubically (P = 0.008). Bacterial N flow (P = 0.002) and true ruminal N disappearance (P = 0.003) increased linearly, and apparent total-tract N disappearance increased quadratically (P = 0.09) with increasing field pea supplementation. No treatment effects were observed for ruminal DM fill (P = 0.82), true ruminal OM disappearance (P = 0.38), apparent intestinal OM digestion (P = 0.50), ruminal ADF disappearance (P = 0.17), apparent total-tract ADF disappearance (P = 0.35), or in situ DM disappearance of forage (P = 0.33). Because of effects on forage intake and ruminal pH, field peas seem to act like cereal grain supplements when used as supplements for forage-based diets. Supplementing field peas seems to effectively increase OM and N intakes of moderate-quality grass hay diets.

Effect of field pea-based creep feed on intake, digestibility, ruminal fermentation, and performance by nursing calves grazing native range in western North Dakota1

“…In our study, ruminal pH was decreased with addition of supplement; however, forage digestibility was not affected. Reed et al (2004a) reported similar results with a decreased ruminal pH with increasing levels of field peas in beef steers fed forage-based diets, however forage digestion was not decreased with the inclusion of field peas. Reed et al (2004a) attributed those results to lower starch and higher degraded intake protein levels than traditional cereal grains, such as corn.…”

“…Although grown primarily as a human food, a potential use for field peas is livestock feed (Reed et al, 2004a,b;Soto-Navarro et al, 2004). The energy content of field peas is similar to corn or other cereal grains, whereas the protein content is approximately 25% (NRC, 1984) and the starch content is 47% compared with other cereal grains (Reed et al, 2004a).…”

Effect of undegradable intake protein supplementation on intake, digestion, microbial efficiency, in situ disappearance, and plasma hormones and metabolites in steers fed low-quality grass hay1

“…Supplemental treatments (1,040 g of DM/hd daily) were control (no supplement) or low, medium, or high levels of UIP (the supplements provided 8.3, 203.8, and 422.2 g of UIP/d and 257.9, 229.8, and 199.7 g of degradable intake protein/d, respectively). Reed et al (2004) reported increased apparent and true ruminal N disappearance and apparent total tract N disappearance with increasing level of field pea supplementation in 8% CP grass hay diets. Field peas were fed at 0, 0.81, 1.62, and 2.43 kg/d and provided approximately 0, 41.7, 83, and 125 g/d of UIP and 0, 148, 296, and 442 g/d of DIP, respectively (Reed et al, 2004).…”

“…Reed et al (2004) reported increased apparent and true ruminal N disappearance and apparent total tract N disappearance with increasing level of field pea supplementation in 8% CP grass hay diets. Field peas were fed at 0, 0.81, 1.62, and 2.43 kg/d and provided approximately 0, 41.7, 83, and 125 g/d of UIP and 0, 148, 296, and 442 g/d of DIP, respectively (Reed et al, 2004). Köster et al (1996) reported a quadratic increase in apparent ruminal N digestibility with the addition of DIP to low-quality hay diets.…”

“…Supplemental protein had no effect (P > 0.13) on in situ forage NDF digestion or CP degradation (Table 5). Similarly, Reed et al (2004) reported no differences in rate of in situ forage DM, NDF, or N disappearance when supplementing increasing level of field peas. Krysl et al (1987) reported no differences for in situ forage NDF disappearance with soybean meal and sorghum supplementation.…”