Inclusion Of Soybean Hulls Research Articles

Milk yield, milk composition, eating behavior, and lamb performance of ewes fed diets containing soybean hulls replacing coastcross (Cynodon species) hay1,2

The objective of this experiment was to evaluate the effects of replacing coastcross hay NDF by soybean hull (SH) NDF on the lactation performance and eating behavior of ewes and also on the performance of their lambs. Fifty-six Santa Inês lactating ewes (56.1 +/- 6.8 kg of initial BW; mean +/- SD) were penned individually and used in a randomized complete block design with 14 blocks and 4 treatments. Diets were formulated to provide similar concentrations of NDF (56%) and CP (16%). The SH NDF replaced 33 (SH33), 67 (SH67), or 100% (SH100) of the NDF contributed by coastcross hay in a 70% forage-based diet (SH0), resulting in SH inclusion rates of 0, 25, 54, and 85% of the dietary DM. Once a week, from the second to the eighth week of lactation (weaning time), ewes were separated from their lambs, stimulated by a 6-IU i.v. oxytocin injection, and hand milked to empty the udder. After 3 h, milk production was obtained after the same procedure. Quadratic effect for milk production (142.4, 179.8, 212.6, and 202.9 g/3 h) and cubic effect for DMI (2.27, 2.69, 3.25, and 3.00 kg/d) were observed as SH inclusion increased from 0 to 85% of the dietary DM. Milk fat (7.59, 7.86, 7.59, and 7.74%), protein (4.53, 4.43, 4.40, and 4.55%), and total solids (18.24, 18.54, 18.39, and 18.64%) did not differ among the 70% forage-based diet and diets with SH NDF replacing 33, 67, or 100% of the NDF. A linear increase in lactose concentration was observed with SH inclusion. Ewe BW gain during the trial showed a cubic response (0.37, 0.03, 4.80, and 2.80 kg) with SH inclusion. The preweaning ADG of lambs increased linearly, and ADG of lambs after weaning decreased linearly with SH inclusion. Final BW of lambs (2 wk after weaning) did not differ among treatments. Eating behavior observations were conducted with 44 ewes. The same facilities, experimental design, dietary treatments, and feeding management were used. Observations were visually recorded every 5 min for a 24-h period when ewes were 46 +/- 6.8 d in milk. Eating time (min/d, min/g of DMI, and min/g of NDF intake) and time expended in rumination and chewing activities (min/g of DMI and min/g of NDF intake) decreased linearly with the addition of SH in the diets. The inclusion of SH improved DMI and milk production, also reflecting on the BW of lambs at weaning. Milk performance was not affected when SH NDF replaced 100% of hay NDF.

Response of lambs fed wheat straw-based diets to supplementation with soybean hulls

A lamb growth and digestion trial and an incubation study were conducted to evaluate the responses to supplementation of a wheat straw (WS)–soybean meal (SB) basal diet with 0, 10, 20, 30, and 40% of soybean hulls (SH) or 29% ground maize and 1% urea (M/U) on a dry matter (DM) basis. DM intake (DMI) increased with SH inclusion up to 30% of the diet, the increase being higher than with the M/U diet. Straw DMI decreased with supplementation, the depression being more severe with M/U than with 30% of SH (405 v. 522 g/day). Digestibilities of diet organic matter (OM) and neutral detergent fibre (NDF) increased, whereas OM digestibility and DM degradation rate (DMc) of WS decreased with SH level. M/U reduced diet NDF digestibility (from 45.9 to 42.3%). OM digestibility and DMc of WS were more severely depressed with M/U than with SH at the similar level of inclusion (from 41.5 to 33.0 v. 39.0% and from 2.63 to 2.16 v. 2.49%/h, respectively). Daily liveweight gain (LWG) and LWG per MJ ME intake (MEI) increased quadratically with SH. Predictions of metabolisable protein (MP) either from the data of the incubation study or from the microbial protein synthesis as assessed by microbial purine excretion, showed that MP may have been in excess of the requirements (11–40%) in diets with 30–40% SH inclusion. Although MEIs of these diets were similar, they gave rise to significantly different LWGs (61.7 v. 84.4 g/day; P < 0.05). By contrast, MEI of the M/U diet was 22% lower than of the diet having 30% SH, but both diets promoted similar LWG. On the whole, the results of this study are interpreted as further evidence that ME of the diets is not a homogeneous entity, the balance of absorbed nutrients being a central issue to predicting the responses of the ruminants.

Soybean hulls as a dietary fiber source for dogs.

In Exp. 1, soybean hull samples were obtained from nine sources across the United States and analyzed for nutrient content to determine their suitability for inclusion in dog diets. Compositional data revealed variation in both the amount of total dietary fiber (TDF; 63.8 to 81.2%) in the soybean hulls and the ratio of insoluble:soluble fiber (5.0:1 to 15.4:1). Crude protein content varied widely among sources, ranging from 9.2 to 18.7%. An in vivo trial (Exp. 2) was conducted using a premium dog diet containing 3.0, 4.5, 6.0, 7.5, or 9.0% soybean hulls (DM basis). There was a negative linear effect (P < .05) of soybean hull inclusion in the diet on DM, OM, TDF, and GE total-tract digestibilities, as well as on calculated ME. Crude protein and fat digestibilities were unaffected by treatment. Based on these results, ileally cannulated dogs were fed diets containing 6.0, 7.5, or 9.0% soybean hulls (DM basis) in addition to diets containing either 0% supplemental fiber or 7.5% beet pulp (Exp. 3). Nutrient digestion at the ileum was unaffected by inclusion of supplemental fiber. Total tract digestion of DM, OM, and GE was lower ( P < .05) for diets containing supplemental fiber when compared with the diet containing 0% fiber. Crude protein and fat digestibilities were unaffected by treatment. There was no difference in nutrient digestibility between those diets containing soybean hulls and a diet containing beet pulp. Soybean hull inclusion in the diet resulted in a negative linear effect (P < .05) on calculated ME, in addition to lowering ME (P < .05) when compared with the 0% fiber control diet. Calculated ME for dogs fed a 7.5% beet pulp-containing diet was lower (P < .05) than that for dogs fed the soybean hull-containing diets. Results indicate that soybean hulls can be an effective dietary fiber source in dog diets.

VISCOMETRIC CHARACTERISTICS OF WHOLE SOYBEAN MILK

ABSTRACTThe rheological behavior of unflavored, whole soybean milk was evaluated. The standard University of Illinois beverage was adequately described by the general power law equation. The soy milk displayed pseudoplastic flow behavior and was mildly thixotropic. The consistency coefficient of the soy beverage decreased with increasing temperature but the flow behavior index was unaltered at higher temperatures. At higher solids levels the apparent viscosity and degree of pseudoplasticity of the beverage increased. Inclusion of soybean hulls in the beverage caused higher apparent viscosity than observed in beverages made from dehulled cotyledons. The doubly homogenized beverage had lower apparent viscosity and greater adherence to Newtonian behavior than the singly homogenized beverage. Beverages prepared from cotyledons blanched in 0.25% NaHCO3 had higher apparent viscosities and were more pseudoplastic than beverages prepared from cotyledons blanched in an acid solution or in tap water.