**2. Search strategy and selection of publications**

The search for potentially eligible publications was conducted using electronic databases Web of science, PubMed, and Scopus. The eligibility was based on the title, abstract, and keywords, and only included articles published in English language. Filters were applied in terms of publication date (2015-01-01 to 2021-09-30 in Web of Science, PubMed, and Scopus).

The developed strings used in the literature search from three databases included: (thermal OR temperature) AND (manipulation) AND (incubation OR embryogenesis OR embryo development) AND (broiler OR chickens OR poultry).

The identified studies from each database were exported to Microsoft Excel workbook to document bibliographic information (author names, title, and publication year). The same software was used to manage and exclude duplicate studies.
