Publikationsdatenbank

Grape marc extract as a feed additive:
physiological insights in broilers (2025)

Art

Poster

Autoren

Ouyang, Huilin (WE 4)

Ebersbach, Luisa (WE 4)

Castillo, Aly

Celeiro, Maria

Lores, Marta

Zentek, Jürgen (WE 4)

Martínez‑Vallespín, Beatriz (WE 4)

Kongress

29th Congress of the European Society of Veterinary & Comparative Nutrition ESVCN

Leipzig, 04. – 06.09.2025

Quelle

Proceedings of the 29th Congress of the European Society of Veterinary & Comparative Nutrition ESVCN : 4th – 6th September 2025 Leipzig, Germany — Wilkens MR, Vervuert I, Heilmann R, Dobenecker B, Rackwitz R (eds.) (Hrsg.)

Leipzig: Müller Buchbinderei GmbH, 2025. LBH: Leipziger Blaue Hefte — S. 71

Sprache

Englisch

Kontakt

Institut für Tierernährung

Königin-Luise-Str. 49
14195 Berlin
+49 30 838 52256
tierernaehrung@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Introduction: There is growing interest in plant-based alternatives to antibiotics for supporting poultry health and performance. Grape marc, a by-product of the wine industry, is rich in bioactive compounds, primarily polyphenols. This study aimed to elucidate the possible modes of action of the bioactive compounds present in a white grape marc extract (GME) and to determine the optimal effective dose in poultry feed.
Animals, material and methods: A total of 400 healthy male broiler chickens (Cobb 500) were randomly assigned to four treatment groups (10 pens/group) based on body weight. The groups received four diets: a control (CON) with no GME, and three treatments (LPP, MPP, HPP) supplemented with low (200 mg/kg), medium (750 mg/kg), and high (1500 mg/kg) polyphenol levels, coming from the extract. The polyphenol levels were selected based on the available literature. Diets, based on maize, wheat, and soybean meal, met or slightly exceeded the recommended nutrient requirements for broilers. Birds received a starter mash (days 0-11) and a pelleted grower diet (days 12-35) with the same GME concentration. On day 35, one bird per pen was euthanized for sample collection (n=10). Breast muscle was used to assess antioxidant capacity via malondialdehyde (MDA) levels, and jejunum tissue was collected for gene expression analysis and Ussing chamber studies, an ex vivo technique to evaluate nutrient transport and intestinal barrier function through electrophysiological measurements. Data were analysed using one-way ANOVA or Kruskal-Wallis-U-Test, depending on normality (significance at p≤0.05). Animal handling procedures were approved by the State Office of Health and Social Affairs Berlin (LAGeSo Reg. No. 0439/17).
Results and discussion: The tested levels of the GME had no effect on breast muscle MDA or immune and barrier-related gene expression in jejunum tissue. On the other hand, the short-circuit current, indicating active ion transport, increased numerically in the HPP group after glucose, lysine, and carbachol addition, though not significantly. Tissue conductance, a measure of epithelial permeability, significantly decreased in all groups receiving the extract after glucose addition (p=0.002), with also numerical decreases after lysine and carbachol, suggesting improved barrier function.
Conclusion: The limited effects observed in this study highlight the need for further research into optimal dosages and mechanisms of action of polyphenol-rich extracts as poultry feed additives. Future work should explore varying concentrations and compositions, and assess their impact across different broiler growth stages and intestinal segments to better understand their potential for enhancing gut health.