Protein value of feather meal for ruminants as affected by blood additions.

In situ digestion and growth studies were conducted to determine the effects of adding blood to feather meal. In the in situ and digestion studies, soybean meal (SBM), blood meal (BM), feather meal (Fth) and two combinations of 55% raw blood and 45% feathers (RB + F) were used. Feathers and blood were combined either before or after steam hydrolysis of feathers. Ruminal escape protein of Fth was greater than that of SBM but less than that of BM (P less than .10) determined in situ after 12 h of incubation. Ruminal in situ protein digestion was lower (P less than .10) than for the other treatments (P less than .10) when blood was hydrolyzed with feathers. Total tract digestibility was similar (P greater than .10) for SBM, BM and the mixture of RB + F when the blood was not hydrolyzed. In the growth study, calves were supplemented with urea, SBM, BM, Fth or a combination of BM and Fth (BM + Fth; each supplied an equal portion of supplemental protein). The slope ratio technique was used to evaluate the protein sources. The most efficiently used protein sources were BM and BM + Fth compared to SBM and Fth (P less than .05). There was a numerical but not significant (P greater than .1) complementary effect of adding BM to Fth. Soybean meal and Fth had similar protein efficiencies (P greater than .20). Estimated amino acid flow to the small intestine based on in situ amino acid degradation suggested that the complementary effect observed for BM + Fth was due to BM supplying lysine and Fth providing sulfur amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Hydrolyzed feather meal as a protein source for growing calves.

Growth, digestion and in situ studies were conducted to determine the protein value of hydrolyzed feather meal (Fth) for growing ruminants. Dacron bags containing blood meal (BM), Fth, corn gluten meal (CGM) and soybean meal (SBM) were suspended in the rumen of two steers for 12 h to estimate escape protein. The escape protein value for Fth, 69.1%, was less than that for BM (82.8%) and CGM (80.4%; P less than .05) but greater than that for SBM (26.6%; P less than .05). Apparent protein digestion by lambs was similar (P greater than .10) for isonitrogenous diets containing urea (U), BM, Fth, CGM and SBM. Amino acid contents of the protein sources before vs after a 12-h ruminal in situ digestion were similar (P greater than .10). In a growth study, a basal diet of 80% ensiled corncobs and 20% alfalfa was fed to 60 individually fed crossbred steers (215 kg BW). Steers were supplemented with U, BM, Fth, 1/2 BM:1/2 Fth, 1/2 BM:1/2 CGM and 1/3 BM:1/3 Fth:1/3 CGM (protein basis). Protein sources were fed at 30, 45 and 60% of the supplemental N with urea supplying the remainder. Protein efficiency was calculated using the slope ratio technique. Protein efficiency was similar (P greater than .10) for BM- and Fth-supplemented calves. Protein efficiencies were similar (P greater than .10) for BM:CGM, BM:Fth and BM:Fth:CGM combinations. These data indicate the Fth is a digestible high escape protein source that is useful in diets for growing ruminants.

Effects of grain type, roughage level and monensin level on finishing cattle performance.

Interactions among grain type (grain sorghum, corn or wheat), roughage level and monensin level were studied in four feedlot trials using pen-fed crossbred yearling cattle. In Trial 1, cattle fed high-moisture corn (HMC) were more efficient (.1537 vs .1406 for gain/feed; P less than .01) than cattle fed dry-rolled grain sorghum (DRGS). As level (0, 3, 6, 9%) of dietary roughage was increased, feed efficiency (gain/feed) decreased (.1566, .1461, .1479, .1382; linear, P less than .01). In Trial 2, a grain type (DRGS; dry-rolled corn, DRC; dry-rolled wheat, DRW) x roughage level interaction was observed for daily gain and feed efficiency. Feed efficiency (gain/feed) was decreased when roughage was added to diets containing DRC (.1608 vs .1750) or DRGS (.1674 vs .1465), but not to the diet containing DRW (.1664 vs .1607). In trial 3, a grain type x roughage level x monensin level interaction (P less than .08) was observed for feed efficiency. The addition of 27.5 mg of monensin per kilogram of the 0% roughage-DRC diet tended to improve feed efficiency (.1633 vs .1531), but the addition of monensin to the 7.5% roughage-DRC diet tended to depress feed efficiency (.1476 vs .1575). The addition of either roughage (.1493 vs .1420) or monensin (.1500 vs .1413) to the DRW diet improved feed efficiency. In Trial 4, cattle fed a combination of 75% DRW and 25% DRC were more efficient (.1618 vs .1591; P less than .06) than cattle fed DRC. As level of roughage (0, 3.75, 7.5%) increased, feed efficiency decreased linearly (.1645, .1599, .1569; P less than .0001). Monensin had no effect on feed efficiency. The value of feeding roughage and monensin was variable both across grain types and within similar grain types.

Rumen fermentation characteristics, nitrogen balance and growth in lambs fed methane digester effluent.

A laboratory silo trial, two lamb metabolism trials and a lamb growth trial were conducted to compare the nitrogen (N) value of swine methane digester effluent (MDE) to that of urea. Using laboratory silos (four/treatment), fermentation characteristics were measured for silages containing cracked corn, ground wheat straw and MDE added at levels of 0, 4, 8 or 12% of silage dry matter (DM). Lactic acid concentration increased linearly with up to 8% MDE addition, but then decreased (P less than .05; quadratic) with 12% MDE. Butyric acid was highest (P less than .05; linear) with 12% MDE, indicating an undesirable fermentation. In a metabolism study, DM, organic matter and N digestibilities and N balance were similar (P greater than .10) between urea and MDE, but DM digestibility was lower (P less than .05) for ensiled diets (52%) than diets fed fresh daily (59.4%). Mean ruminal volatile fatty acid, ruminal ammonia-N and plasma urea-N concentrations were similar (P greater than .10) between urea- and MDE-fed lambs. Plasma urea-N was higher (P less than .05) and ruminal isovaleric acid lower (P less than .05) in animals fed ensiled than fresh diets. In the second metabolism trial, digestibility of N was lowest (P less than .05) for MDE (51.2%) and highest for soybean meal (SBM; 71.8%), but N balance was similar among all diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Energy value of corn wet milling by-product feeds for finishing ruminants.

Five trials were conducted to evaluate the energy value of corn wet milling by-products in finishing diets. In trials 1 (45 finishing lambs, 34 kg) and 2 (70 digestion wethers, 32 kg), Rambouillet X Suffolk lambs fed corn gained faster (P less than .10), more efficiently (P less than .10) and had higher (P less than .01) digestibilities of neutral and acid detergent fiber (NDF, ADF) and starch than lambs fed dry corn gluten feed (DCGF). Lambs fed wet corn gluten feed (WCGF) consumed less feed (trial 1, P less than .05; trial 2, P less than .01), were more efficient (P less than .01) NDF and ADF digestibilities than lambs fed DCGF. Starch, NDF and ADF digestion were higher (P less than .01) for lambs fed WCGF vs wet corn bran (WCB). Lambs fed WCGF gained faster (P less than .10) and consumed more (trial 1, P = .12; trial 2, P less than .10) feed than lambs fed WCB. Dried corn bran increased (trial 1, P less than .05; trial 2, P less than .01) intake and increased (P less than .01) dry matter digestion (DMD) compared with WCB. In trial 3, rates of in vitro dry matter and NDF disappearance were similar among by-product feeds. In trial 4 (50 individually fed Shorthorn-Hereford-Angus steers, 316 kg), steers fed WCGF tended to consume more (P = .14) feed than steers fed DCGF. Corn gluten feed (CGF) replacing 0 to 46% corn decreased gain (linear, P less than .05) and DMD (linear, P less than .10), while starch digestion was highest for 23% CGF (quadratic, P less than .01). A level X CGF type interaction (P = .15) occurred for efficiency due to the lower gain of steers fed 46% DCGF. The efficiency of CGF utilization was 97% that of corn when WCGF replaced 23 or 46% corn or DCGF replaced 23% corn. Dry CGF replacing 46% corn had 87% the value of corn. In trial 5 (186 Hereford-Angus cattle, 310 kg), DCGF replacing 25 and 50% corn had 97 to 100% the efficiency of corn, while intake and gain were not affected. Dry CGF replacing 25 and 50% corn silage increased (linear, P less than .05) intake 11.3% and gain 13.8%. In ruminants, CGF is highly digestible and feed efficiency is similar to corn when WCGF is fed up to 50% of the grain component or when DCGF is fed up to 25% of the grain component.

Effect of corn hybrid and grain processing method on rate of starch disappearance and performance of finishing cattle.

Two trials evaluated the effects of different corn hybrids on in vitro rate of starch disappearance and finishing cattle performance. Hybrids were selected, based on in vitro rate of starch disappearance (A = fastest, B = intermediate, C = slowest). In Trial 1, hybrids A and B were fed as dry-rolled and early-harvested, high-moisture (28%) corn and hybrid C was fed as dry-rolled corn. Cattle fed dry-rolled hybrid A gained faster (P < .10) and more efficiently (P < .10) than cattle fed dry-rolled hybrids B and C. No differences were observed in DMI, quality grade, or fat thickness among hybrids fed dry-rolled. Dry matter intake was lower (P < .10) and feed efficiency was improved (P < .10) for cattle fed corn hybrids A and B as high-moisture corn compared with those same hybrids fed dry-rolled. In Trial 2, hybrids A, B, and C were fed as dry-rolled and early-harvested, high-moisture (29, 28, and 29% moisture, respectively) corn. Performance and carcass measurements were not affected by hybrid fed. Cattle fed high-moisture corn gained faster (P < .10), consumed less DM (P < .01), and were more efficient (P < .01) than cattle fed the same hybrids dry-rolled. Across trials, hybrids, and processing methods, in vitro rate of starch disappearance was correlated with feed efficiency (r2 = .58, P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)