Risk factors associated with enteric parasite infection in pigs raised in different production systems

Brazilian swine farming relies on diverse production systems where maintaining animal health is fundamental. Parasitic diseases represent a significant factor affecting swine performance and public health, especially in the case of gastrointestinal parasites. This study investigated the prevalence, diversity, and risk factors of helminths and protozoa in swine raised under Intensive Management System (IMS), Semi-Intensive Management System (SIMS), and Family Subsistence Management System (FSMS) in the microregions of Andradina (SP) and Paranaíba (MS). A total of 150 fecal samples were collected and analyzed using quantitative (EPG/OPG), qualitative, and morphological coproparasitological techniques, with socioeconomic and management data collected for risk factor analysis. Results demonstrated that the FSMS consistently presented the highest parasitic burden and diversity. Oesophagostomum spp. was the most prevalent helminth in FSMS (82.0%) compared to 6.0% in IMS, and the mean helminth egg count in FSMS sows reached 1650 EPG, a sharp contrast to 85.74 EPG in IMS. The highest species diversity, including all nine coccidia species identified (eight Eimeria spp. and Cystoisospora suis), was found in FSMS, which also recorded the highest prevalence of the clinically relevant species Cystoisospora suis (12.0%). Multivariate analysis confirmed that the production system is the most influential risk factor; the FSMS was significantly associated with a high probability of severe infection, while the IMS provided a protective effect. Furthermore, dirt floors and substandard facilities increased the risk of infection, while balanced feeding acted as a significant protective factor. These findings underscore that deficiencies in infrastructure and sanitary management in less-technified systems are the primary drivers of parasitic load and environmental contamination.