Effects of urea, isolated soybean protein and blood meal on growing steers fed a corn-based diet

Abstract

A short term feeding trial was conducted to assess effects of nitrogen (N) supplementation on growing cattle and the ability of the Cornell Net Carbohydrate and Protein System (CNCPS) to predict responses. Four corn-based diets were used: (1) a 30% ruminal N-deficient control diet; (2) a urea supplemented diet; (3) a urea+isolated soy protein (ISP) diet; and (4) a urea+ISP+blood meal (BM) diet. Four Holstein steers (average initial body weight of 251 kg) were randomly assigned in a 4 × 4 Latin Square treatment design. Steers were fed 95% of ad libitum intake on an hourly basis, and 500 g of oestradiol-17␤ were administered twice daily. Average daily gain (ADG) increased (P < 0.05) when urea was added to the diet, but including urea +ISP was not better than the control or urea alone (P > 0.05). The urea + ISP + BM diet was better than the control or urea + ISP diets (P < 0.05), but it was not better than urea alone (P > 0.05). Addition of ISP or ISP+BM to the urea diet did not increase whole tract true digestibility of neutral detergent fibre, acid detergent fibre, or apparent digestibility of the dietary non-structural carbohydrate fraction (P > 0.05). The addition of urea, ISP or ISP+BM to the control diet caused an increase in N intake (P < 0.05), but faecal N did not increase (P > 0.05). Urinary N excretion increased 2.8-fold compared to the control diet when urea, ISP or ISP+BM were added (P < 0.05), but there was no difference between these latter three treatments (P > 0.05). Urea, ISP and ISP + BM increased N retention (P < 0.05), and ISP + BM was higher than urea and ISP (P < 0.05). The numerical difference in N retention between urea and urea + ISP was not significant (P > 0.05). When urea, ISP or ISP + BM were added, plasma urea N increased (P < 0.05), but these three treatments had no effect on glucose, non-esterified fatty acids or insulin (P > 0.05). Results show that a ruminal N-deficiency can have a negative impact on ADG, and this effect was consistent with predictions made by the CNCPS. Substitution of urea * Corresponding author. Tel.: +43-1-47654x3285; fax: +43-1-47654x3254. E-mail address: knaus@edv1.boku.ac.at (W.F. Knaus).0377-8401/02/$ -see front matter © 2002 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 7 -8 4 0 1 ( 0 2 ) 0 0 1 8 2 -7 4 W.F. Knaus et al. / Animal Feed Science and Technology 102 (2002) [3][4][5][6][7][8][9][10][11][12][13][14] by ISP did not cause an increase in ADG, indicating that ISP may not be as ruminally degradable as urea. Blood meal increased ADG, consistent with CNCPS predictions. Because ISP could have been a source of ruminally undegradable protein rather than ruminal peptides and amino acids, the peptide stimulation predictions of the CNCPS could not be evaluated.

Feed intake and growth performance of goats supplemented with soy waste

“…This might be attributed to the high nutritional characteristics of soy waste, including ME and CP contents. Knaus et al (2002) reported that N absorption and N retention increased, when soy protein-based diets were fed to steers. Kim et al (2012) also reported that dietary soybean curd residue could improve the growth rate of cattle.…”

The effects of concentrate added to pineapple (Ananas Comosus linn. Mer.) waste silage in differing ratios to form complete diets, on digestion, excretion of urinary purine derivatives and blood metabolites in growing, male, Thai swamp buffaloes

“…Similarly, Guerino et al (1991) and Ragland-Gray et al (1997) found higher plasma insulin after the infusion of casein into the abomasum in steers. But, Knaus et al (2002) observed that plasma glucose and NEFA in growing cattle did not increase when the protein in the diet increased. On the other hand, when decreasing energy sources provided by pineapple waste silage and increasing energy provided by concentrate with increasing in plasma insulin concentration.…”

Effect of energy and protein levels on nutrient utilization and their requirements in growing Murrah buffaloes

“…The DM, OM, NDF and acid detergent fiber (ADF) digestibility in male Thai swamp buffalo calves ) and Thai-indigenous heifers ) and the DM and OM digestibility in yearling heifers were not altered by dietary CP levels, though a significant increase in the NDF and ADF digestibility was observed with increased dietary CP by Chumpawadee et al (2009). Knaus et al (2002) increased the CP level from 7.9 to 15.3 % in the diet of growing steers and reported an increase in NDF digestibility from 39.8 to 48.0 %. Mehra et al (2001) reported a non-significant difference in the NDF digestion with increasing levels of energy and protein in experimental diets.…”