Effects of diet and Aspergillus oryzae extract or Saccharomyces cervisiae on growth and carcass characteristics of lambs and steers fed to meet requirements of natural markets1,2

Abstract

Two studies were conducted to determine the effects of diet and feed additive on growth and carcass characteristics of lambs and cattle destined for all natural markets. In Exp. 1, 48 Dorset × Hampshire lambs (initial BW 29.4 ± 0.1 kg) were used in a randomized complete block experiment to determine the effects of Aspergillus oryzae extract, Amaferm (AMF) supplementation (1 g/d) in an 85% concentrate diet on growth and carcass characteristics. Lambs were allotted to 12 pens (4 lambs per pen), and blocked by sex and BW. Lambs were fed until the average BW of each pen reached a target BW (55.4 kg for wethers and 50.0 kg for ewes), at which time the entire pen of lambs was slaughtered. Amaferm resulted in a greater (P=0.07) G:F. In Exp. 2, 168 crossbred steers (initial BW 300 ± 0.7 kg) were used in a trial with a 3 × 2 factorial arrangement of treatments to examine the effects of 0.5 g/d of Saccaromyces cervisiae boulardii CNCM 1079-Levucell SB (LEV), or 3 g/d of AMF with 2 corn sources, dry whole-shelled corn or high moisture corn, on growth and carcass characteristics. Neither LEV nor AMF improved (P>0.10) carcass characteristics compared with control or non-feed-supplemented steers. Addition of LEV to high-concentrate, corn-based diets did not improve (P>0.10) growth performance of feedlot steers. However, addition of AMF to a diet composed of dry whole-shelled corn resulted in an improvement (P<0.05) in G:F (0.208 vs. 0.194). Results indicate that at the amounts fed, AMF may improve G:F for lambs and steers fed dry corn-based finishing diets.

Effects of feeding different levels of chromium-enriched live yeast in hairy lambs fed a corn-based diet: effects on growth performance, dietary energetics, carcass traits and visceral organ mass

“…As discussed previously, the effect of YC supplementation, alone (not enriched with Cr), on carcass characteristics (Jones et al 1997;Kawas et al 2007;Payandeh and Kafilzadeh 2007;Titi et al 2008;Zerby et al 2011), wholesale cuts (Titi et al 2008;Whitley et al 2009), or visceral mass (Belewu and Jimoh 2005) of feedlot lambs has been small and non-appreciable. Thus, is expected that the changes in carcass measures in the present experiment are more directly related to Cr intake, per se.…”

“…Likewise, Adams et al (1981) reported no differences in DMI of lambs fed a 50 : 50 forage : concentrate diet supplemented with 2.5% of live yeast (targeted 20 g/lamb.day of S. cerevisiae) during a 73-day growing-finishing period. Supplemental Aspergillus oryzae (1 g/day) did not affect DMI of lambs fed a high-energy finishing diet during a 72-day period (Zerby et al 2011). In steers, supplementation with 10 g/day YC did not affect the DMI of steers fed a 74% barley-based finishing diet (Mir and Mir 1994).…”

Growth, ruminal measurements, and health characteristics of Holstein bull calves fed an Aspergillus oryzae fermentation extract

“…It can be used as a prebiotic in calf feed (Beharka et al, 1991), but has more commonly been used in sheep and beef finishing diets (Schmidt et al, 2004;Zerby et al, 2011). Aspergillus oryzae has long been used in the Japanese food industry for fermenting foods such as saki, soy sauce, and miso, and it is regarded as safe because it does not produce aflatoxin (Uchida et al, 2006).…”

Rumen microorganisms and fermentation

“…Specific strains of bacteria are used for this purpose in animal feed (Donohue 2006). In beef cattle production systems, antibiotics are used to decrease the frequency of metabolic disorders, improve efficiency, and reduce ruminal acidosis, however, the use of some unnatural antibiotics is restricted (Zerby et al 2011). Some bacterial species of the genera Lactobacillus and Bifidobacterium have been shown to have good results as probiotics in ruminants, increasing levels of weight gain and efficiency (Whitley et al 2009).…”