Influence of ardacin supplementation on feedlot performance and digestive function of cattle.

Abstract

A feedlot growth-performance trial and a metabolism trial were conducted to evaluate a dose response to ardacin (a glycopeptide antibiotic). Treatments consisted of an 88% concentrate finishing diet supplemented to contain (DM basis) 0, 8.25, 16.5., or 33 mg ardacin/kg. The growth-performance trial (129 d) involved 120 heifers and 120 steers in a randomized complete block design. There were no interactions (P less than .10) between sex and response to ardacin. Average daily gain increased (P less than .05) and DM conversion decreased (P less than .01) with increasing levels of ardacin supplementation. At the 33 mg/kg level of supplementation, ADG and DM conversion were improved 10.6 and 5.6%, respectively. Four Holstein steers (344 kg) with cannulas in the rumen and proximal duodenum were used to evaluate treatment effects on characteristics of digestion. There were cubic effects of ardacin on ruminal starch digestion (P less than .05), microbial N synthesis (MNS, P less than .10), and microbial efficiency (MNEFF, grams of MNS/kilogram of OM fermented). For the 16.5 and 33 mg/kg levels of supplementation, ruminal starch digestion was increased 4.9%, and MNS and MNEFF were decreased 12.9 and 15.6%, respectively. Postruminal and total tract digestion of N increased linearly (P less than .10) with ardacin supplementation. Total tract digestion of OM, ADF, and starch were not affected (P greater than .10). Ardacin did not influence (P greater than .10) ruminal pH or molar VFA proportions. It is concluded that supplementation of a finishing diet with 33 mg ardacin/kg will enhance ADG and DM conversion of feedlot steers and heifers.

Avoparcin and monensin effects on the digestion of nutrients in dairy cows fed a mixed diet

“…There was a tendency for more starch to be digested in the small intestine of avoparcin-fed cows than in controlfed cows (1700 vs. 1500 g d-r): but the differences were not significant (P > 0.05). In agreement with the present study, Darden et al (1985) Gomez et al (1991) (Zinn et al 1991) and monensin (Muntifering et al 1981) reduced bacterial N by 9 and l4Vo, respectively, in cattle fed a corn-based diet; whereas feed bypass was increasedby 2O and I5Vo. But no differences were detected in bacterial N and dietary N flows to the duodenum in steers fed aTOVo concentrate diet supplemented with either ayoparcin or monensin (Darden et al 1985).…”

“…The effect of both additives on microbial synthesis and ruminal degradation of feed N are similar to responses observed with ardacin, monensin and lasalocid (Muntifering et al 1981; Morris et al' 1990;Zinn et al 1991). The small intestine digestion of N (g d-r) tended to be increased (P < 0.058) in cows treated with monensin.…”

“…Solubility, extent of degradability and propensity to liberate NH3-N in ruminal fluid incubations haye been shown to affect the magnitude of proteolytic and deaminative inhibition caused by antibiotics (Dinius 1978 Stern et al (1985) but are within the range reported by others (Zinn et al 1991). The effect of both additives on microbial synthesis and ruminal degradation of feed N are similar to responses observed with ardacin, monensin and lasalocid (Muntifering et al 1981; Morris et al' 1990;Zinn et al 1991).…”

Avoparcin and Monensin Effects on Digestive Function in Cows Fed a High Forage Diet

“…Compared with the control diet, neither AVO nor MON diets significantly (P > 0.05) affected ruminal pH and total VFA concentrations ( Table 2), which is consistent with results of Bogaert et al(1991) and Rogers et al (1991), who reported no effect of glycopeptide and ionophore antibiotics on ruminal total VFA concentrations, although other researchers (Darden et al 1985;Zinn et al 1991) have found that AVO, ardacin (a glycopeptide antibiotic), and MON decreased ruminal VFA. In terms of VFA molar percentages, only butyrate and valerate were affected by MON treatment (P < 0.05); the molar percentages were 77.0% that of the unsupplemented control.…”

Identification of Unique Type II Polyketide Synthase Genes in Soil

“…Jadomycins have a wide spectrum of biological activity and are effective against gram-positive and gram-negative bacteria and even yeasts. Ardacin is a glycopeptide antibiotic shown to be effective against gram-positive bacteria (23,41). As with the 2S1 and 2S5 clades of sequences, their percent identity to known KS ␣ genes was less than 80%, indicating that the organisms containing these genes have yet to be isolated or have not been analyzed for their PKS gene pathways.…”