Field evaluation of Nzi and modified Nzi traps for sampling of Stomoxys calcitrans at dairy farms in Uruguay.

Stomoxys calcitrans (Linnaeus, 1758), the stable fly, is a hematophagous pest that affects animal livestock worldwide by lowering productivity and mechanically transmitting pathogens. This study evaluated the effectiveness of the Nzi trap and a modified version (with and without bait) for capturing stable flies on two dairy farms in southwestern Uruguay, under conditions of natural infestation by these flies. The study used a 4 × 4 Latin square design with five replicates conducted independently at each dairy farm. Traps at each dairy were emptied daily to identify and count stable flies before being rotated and reset at the next planned location. Among all configurations, standard Nzi traps captured the highest number of S. calcitrans compared to the other trap evaluated, regardless of whether an attractant was used. This study represents the first evaluation in South America of Nzi traps for S. calcitrans used in combination with a commercial bait. Findings indicate that Nzi traps are a potentially effective tool for capturing S. calcitrans at dairy farms.