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Cheng J.,University of Veterinary and Animal Sciences | Sun N.,University of Veterinary and Animal Sciences | Zhao X.,University of Veterinary and Animal Sciences | Niu L.,University of Veterinary and Animal Sciences | And 7 more authors.
Journal of Microbiology and Biotechnology | Year: 2013

Seventeen compounds derived from traditional Chinese medicines (TCMs) were tested for their antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV) in vitro. Visualization with the cytopathologic effect (CPE) assay and the 3-(4, 5-dimethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide test were used to determine the 50% cytotoxic concentration (CC50) and 50% effective concentration (EC50) in cultured Marc-145 cells. Among the tested compounds, chlorogenic acid and scutellarin showed potential anti-PRRSV activity. The EC50 values were 270.8 ± 14.6 μg/ml and 28.21 ± 26.0 μg/ml and the selectivity indexes were >5.54 and 35.5, respectively. The time-of-addition and virucidal assay indicated that the anti-PRRSV activity of the two compounds could be due to their inhibiting the early stage of virus replication and/or inactivating the virus directly. The inhibition of the virus attachment was not observed in the adsorption inhibition assay. The inhibition ratios of chlorogenic acid and scutellarin were, respectively, 90.8% and 61.1% at the maximum non-cytotoxic concentrations. The results have provided a basis for further exploration of their antiviral properties and mechanisms in vivo. We believe that the chlorogenic acid and scutellarin have a great potential to be developed as new anti-PRRSV drugs for clinical application. © 2013 by The Korean Society for Microbiology and Biotechnology. Source


Wang C.,Shanxi Agricultural University | Liu Q.,Shanxi Agricultural University | Pei C.X.,Shanxi Agricultural University | Li H.Y.,Shanxi Agricultural University | And 6 more authors.
Livestock Science | Year: 2012

The objective of this study was to evaluate the effects of 2-methylbutyrate (2MB) supplementation on rumen fermentation, ruminal enzyme activities, urinary excretion of purine derivatives and feed digestibility in the total tract of steers. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were: control (without 2MB), L2MB, M2MB and H2MB with 8.4, 16.8 and 25.2. g 2MB per steer per day, respectively. 2-methylbutyrate was hand-mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate (dry matter [DM] basis). Dry matter intake (averaged 9. kg/d) was restricted to a maximum of 90% of ad libitum intake. Ruminal pH was linearly decreased, whereas total VFA concentration (range of 64.19-71.06. mM) was linearly (p< 0.01) and quadratically (p< 0.01) increased with increasing 2MB supplementation. Ratio of acetate to propionate increased linearly (p< 0.01) from 2.53 to 3.80 as 2MB supplementation increased due to the increased in acetate production and decreased in propionate production. Activities of CMCase and xylanase were linearly increased, whereas that of protease was linearly reduced with increasing 2-methylbutyric supplementation. In situ ruminal NDF degradation of corn stover was improved but the CP degradability of soybean meal was decreased with increasing 2MB supplementation. Urinary excretion of purine derivatives was quadratically (p< 0.01) changed with altering 2MB supplementation (52.74, 58.50, 59.17 and 54.36. mmol/d for control, low, medium and high 2MB supplementation, respectively). Similarly, digestibilities of DM, NDF and CP in the total tract were also linearly and quadratically increased with increasing 2MB supplementation. The present results indicate that supplementation of diet with 2MB improved rumen fermentation and feed digestion in beef cattle. It was suggested that the 2MB stimulated the digestive microorganisms or enzymes in a dose-dependent manner. In the experimental conditions of this trial, the optimum 2MB dose was about 16.8. g 2MB per steer per day. © 2012 Elsevier B.V. Source


Liu Q.,Shanxi Agricultural University | Wang C.,Shanxi Agricultural University | Pei C.X.,Shanxi Agricultural University | Li H.Y.,Shanxi Agricultural University | And 10 more authors.
Livestock Science | Year: 2014

The objective of this study was to evaluate the effects of isovalerate supplementation on microbial status and ruminal enzyme activities in steers fed on corn stover based diet with a low proein. Eight ruminally cannulated Simmental steers were used in a replicated 4×4 Latin square experiment. The treatments were control (without isovalerate), LIV, MIV and HIV with 8.4, 16.8 and 25.2. g isovalerate per steer per day, respectively. Isovalerate was hand- mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate (dry matter [DM] basis). Dry matter intake (averaged 9. kg/day) was restricted to a maximum of 90% of ad libitum intake. Whether direct counts, cultured using a roll-tube technique or real-time PCR quantification, population of total bacteria, cellulolytic bacteria and anaerobic fungi were linearly increased, whereas that of protozoa and total methanogens was linearly reduced with increasing isovalerate supplementation. Real-time PCR quantification of population of R. albus, R. Flavefaciens, B. Fibrisolvens and F. succinogenes was linearly increased (p<0.04) with increasing isovalerate supplementation. Activities of CMCase, xylanase and β-glucosidase were linearly increased (p<0.05), whereas that of protease was linearly reduced (p=0.005) with increasing isovalerate supplementation. Methane production was linearly decreased (p<0.001) with increasing isovalerate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover was linearly increased (p<0.001), whereas that of crude protein in diet was linearly decreased (p<0.001) with increasing isovalerate supplementation. The present results indicate that supplementation of diet with isovalerate improved microbial status and ruminal enzyme activities in steers. It was suggested that the isovalerate stimulated the digestive microorganisms or enzymes in a dose-dependent manner based on corn stover diet with a low protein. In the experimental conditions of this trial, the optimum isovalerate dose was about 16.8. g isovalerate per steer per day. © 2014 Elsevier B.V. Source


Wang C.,Shanxi Agricultural University | Liu Q.,Shanxi Agricultural University | Zhang Y.L.,Shanxi Agricultural University | Pei C.X.,Shanxi Agricultural University | And 7 more authors.
Journal of Animal Physiology and Animal Nutrition | Year: 2015

The objective of this study was to evaluate the effects of isobutyrate supplementation on rumen microflora, enzyme activities and methane emissions in Simmental steers consuming a corn stover-based diet. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were control (without isobutyrate), low isobutyrate (LIB), moderate isobutyrate (MIB) and high isobutyrate (HIB) with 8.4, 16.8 and 25.2 g isobutyrate per steer per day respectively. Isobutyrate was hand-mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate [dry matter (DM) basis]. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 90% of ad libitum intake. Population of total bacteria, cellulolytic bacteria and anaerobic fungi were linearly increased, whereas that of protozoa and total methanogens was linearly reduced with increasing isobutyrate supplementation. Real-time PCR quantification of population of Ruminococcus albus, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens and Fibrobacter succinogenes was linearly increased with increasing isobutyrate supplementation. Activities of carboxymethyl cellulase, xylanase and β-glucosidase were linearly increased, whereas that of protease was linearly reduced. Methane production was linearly decreased with increasing isobutyrate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover were linearly increased, whereas that of crude protein in diet was linearly decreased with increasing isobutyrate supplementation. The present results indicate that isobutyrate supplemented improved microflora, rumen enzyme activities and methane emissions in steers. It was suggested that the isobutyrate stimulated the digestive micro-organisms or enzymes in a dose-dependent manner. In the experimental conditions of this trial, the optimum isobutyrate dose was approximately 16.8 g isobutyrate per steer per day. © 2014 Blackwell Verlag GmbH. Source

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