Biosecurity on pig farms in Europe: A meta-review of knowledge gaps

Biosecurity measures (BSMs) are essential for preventing the introduction and spread of infectious diseases within pig production systems, thereby supporting animal health, welfare, productivity, and responsible antimicrobial use. Numerous BSMs applied on European pig farms are discussed in literature reviews. Hence, a meta-review was conducted to map these BSMs, to highlight knowledge gaps. Eleven reviews covering European pig production systems were identified. Forty biosecurity variables were defined a priori for data extraction and grouped into ten groups covering farm geography and environmental interface, contact control, transport of feed and animals, waste management, personnel and visitor management, feed and stock management, pig management, land and outdoor area management, animal health and care, and hygiene management. The extent to which each BSM was covered across reviews was assessed by experts. Overall, the existing review literature varied widely in scope and methodological approach. Core operational measures such as hygiene, transport, waste management, and animal health practices were frequently reported. However, approximately 50-70% of the reviews provided only limited detail on their implementation. In contrast, measures related to environmental interfaces, land and outdoor area management, and barriers for contact control were among the least represented, with approximately 50-67% assessed as "not mentioned" across the included reviews. A clear knowledge gap was identified regarding BSMs relevant to production systems in which pigs have access to outdoor environments. Findings from this meta-review point to the need for a standardized framework to guide documentation of biosecurity measures across literature reviews.