Subclinical gastrointestinal nematode infections in sheep from San Pedro: A One Health approach for parasite control and conceptual management analysis
DOI:
https://doi.org/10.18004/mem.iics/1812-9528/2026.e24142601Keywords:
GIN, prevalence, parasitologyAbstract
Gastrointestinal nematode (GIN) infections continue to be one of the main health constraints in small ruminant production systems, potentially affecting productivity, compromising reproductive efficiency, and increasing production costs. Recently, a new challenge has emerged: the potential zoonotic risk. The objective of this study was to provide field evidence on the presence, prevalence, and intensity of GIN infections in clinically asymptomatic sheep and to integrate these findings into a critical review of their productive and sanitary relevance, serving as a basis for the design of control strategies. A descriptive cross-sectional study was conducted on a farm in the department of San Pedro, Paraguay. Fecal samples were collected directly from the rectum of 59 sheep and analyzed using qualitative flotation techniques and the McMaster method to determine eggs per gram (EPG) of feces. GIN eggs were detected in 78% (46/59) of the animals, with identification achieved only at the family level. The mean infection intensity was 268.87 EPG, indicating mild infections at the flock level. The high prevalence combined with low intensity demonstrates the presence of subclinical parasitism in apparently healthy sheep. These findings highlight the importance of routine monitoring to identify asymptomatic carriers, which contribute to pasture contamination and represent a health risk. In line with current literature, the relevance of subclinical GIN infections for animal health, productivity, and the development of sustainable parasite control strategies in small ruminant systems with potential zoonotic risk is highlighted.
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