{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:12:46Z","timestamp":1789992766123,"version":"4.0.1"},"reference-count":31,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T00:00:00Z","timestamp":1789862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Enteric methane emissions and feed efficiency are increasingly being investigated as complementary traits for improving the environmental sustainability and productivity of ruminant systems. This study conducted a bibliometric and thematic review of scientific literature published between 2016 and 2025 to characterize research trends and synthesize evidence on the association between feed efficiency and enteric methane emissions in ruminants. Publications retrieved from Scopus and Web of Science were analyzed using Bibliometrix and VOSviewer, including scientific production, collaboration networks, keyword co-occurrence, thematic evolution, and burst analyses. A total of 659 publications from 158 sources were identified, with an annual growth rate of 13.97% and 40.36% international co-authorship. Scientific production increased from 37 publications in 2016 to 120 in 2025. Thematic analyses revealed a transition from the characterization of feed-efficiency and methane traits toward integrated approaches involving methane mitigation, nutrient utilization, rumen microbiology, genomics, and precision phenotyping. Evidence indicates that improved feed efficiency can contribute to lower absolute methane emissions, particularly through reduced feed intake, but does not consistently imply lower methane production relative to feed intake or productive output. Feed efficiency and methane emissions should therefore be considered complementary rather than interchangeable traits when developing sustainable breeding, nutritional, and management strategies.<\/jats:p>","DOI":"10.3390\/ani16182957","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T11:05:53Z","timestamp":1789988753000},"page":"2957","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Global Research Trends and the Association Between Feed Efficiency and Enteric Methane Emissions in Ruminants: A Bibliometric and Thematic Review"],"prefix":"10.3390","volume":"16","author":[{"given":"Eduarda Teles","family":"Botelho","sequence":"first","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karoline Ferreira dos","family":"Santos","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucas Lino","family":"Barroso","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria J\u00falia Pereira","family":"Cordeiro","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leandro Torres de","family":"Sousa","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruna Aparecida Fernandes","family":"Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hugo Farias","family":"Souza","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda Rodrigues de","family":"Sousa","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni B\u00e1rbara","family":"Nunes","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8294-0500","authenticated-orcid":false,"given":"Lucas Ferreira","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Rio Verde, Rio Verde 75901-970, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janaina Gomes Ara\u00fajo","family":"Santos","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5927-0545","authenticated-orcid":false,"given":"Josiel","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Goiano (IF Goiano), Campus Campos Belos, Campos Belos 73840-000, GO, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,20]]},"reference":[{"key":"ref_1","unstructured":"Food and Agriculture Organization of the United Nations (2021). 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