{
  "abstract": "The European Union is the world's largest producer of olives (Olea europaea), generating substantial amounts of by-products that require revalorization. Among these, dry olive cake is rich in dietary fiber and phenolic compounds, making it a promising ingredient for poultry nutrition. This study evaluated the effects of including 2% dry olive cake in laying pullet diets compared with a control diet, assessing performance, apparent total tract retention (ATTR), intestinal morphology, gene expression, cecal microbiota, and volatile fatty acids (VFA) after 28 days of trial. Two diets were formulated: a control diet with 2% sepiolite and a diet with 2% dry olive cake (DOC), administered to 6-weeks-old pullets housed in 12 cages (6 replicate cages per dietary treatment, with three birds per cage). DOC improved ATTR (P<0.05), while performance remained unaffected (P>0.05). Gut morphology improved in the duodenum, where crypt depth decreased and the villus length-to-crypt depth ratio increased (P<0.05). Gene expression analysis revealed downregulation of inflammatory genes (IL-2, TNF-α, IFN-γ) and RARRES1, alongside upregulation of genes related to barrier function (MUC2), antimicrobial defense (AvBD4), and fatty acid transport (FAT-CD36) (P<0.05). Cecal microbiota showed trends toward distinct community structures (Jaccard and Bray-Curtis indices; P<0.10), with higher richness (Chao1 and Fisher; P<0.05), greater Butyricicoccaceae, and reduced Proteobacteria (P<0.05). These changes were accompanied by greater total VFA production, particularly acetic, propionic, butyric, and valeric acids, with a higher proportion of butyrate (P<0.05). Overall, 2% dry olive cake improved gut health, microbiota, and nutrient utilization without affecting performance, supporting its potential as a sustainable, functional fiber source in the feed of laying pullets.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Animal Production, Faculty of Veterinary Science, Regional Campus of International Excellence \"Mare Nostrum\", University of Murcia, Espinardo, Murcia, 30100, Spain.",
    "Department of Animal Production, Faculty of Veterinary Science, Regional Campus of International Excellence \"Mare Nostrum\", University of Murcia, Espinardo, Murcia, 30100, Spain. Electronic address: lucia.ayalag@um.es.",
    "Department of Animal Health, Faculty of Veterinary Science, Regional Campus of International Excellence \"Mare Nostrum\", University of Murcia, Espinardo, Murcia, 30100, Spain."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Eduardo Ruiz"
    },
    {
      "affs": [
        0
      ],
      "name": "Fuensanta Hernández"
    },
    {
      "affs": [
        0
      ],
      "name": "Josefa Madrid"
    },
    {
      "affs": [
        0
      ],
      "name": "Cristian Jesús Sánchez"
    },
    {
      "affs": [
        0
      ],
      "name": "Ana Montalbán"
    },
    {
      "affs": [
        1
      ],
      "name": "Lucía Ayala"
    },
    {
      "affs": [
        2
      ],
      "name": "Nieves Ortega"
    },
    {
      "affs": [
        0
      ],
      "name": "Silvia Martínez-Miró"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/54zvya74svws2.bib",
  "cited_by": 0,
  "doi": "10.1016/j.psj.2026.107906",
  "fulltext_url": "https://europepmc.org/articles/PMC13677395",
  "id": "54zvya74svws2",
  "issns": [
    "0032-5791",
    "1525-3171"
  ],
  "landing_url": "https://europepmc.org/article/MED/42849227",
  "language": "eng",
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1103|Animal Nutrition and Physiology"
    ]
  ],
  "openalex": "W7220462383",
  "pdf_url": "https://europepmc.org/articles/PMC13677395?pdf=render",
  "pmcid": "PMC13677395",
  "pmid": "42849227",
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/54zvya74svws2.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:10Z",
      "native_id": "MED:42849227",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42849227"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "openalex:1103|Animal Nutrition and Physiology",
      "subfield": "zoology-behaviour"
    }
  ],
  "title": "Dry olive cake, an olive by-product, as a functional fiber source in diets for laying pullets: effects on growth and gut health.",
  "title_text": "Dry olive cake, an olive by-product, as a functional fiber source in diets for laying pullets: effects on growth and gut health.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:10Z",
  "url": "https://research.draconitic.com/paper/54zvya74svws2",
  "venue": "Poultry science",
  "versions": []
}