The efficacy and persistence of ivermectin-3.15% (IVM-3.15%) and moxidectin-10% (MOX-10%) against natural infections of gastrointestinal nematodes (GIN) in cattle in the Mexican tropics were evaluated. Thirty-three heifers were divided into three groups of 11 animals each, receiving the following treatments: group one treated with IVM-3.15% (0.63 mg/kg bw) subcutaneously, group two was treated with MOX-10% (1.0 mg/kg bw) subcutaneously, and group three was the untreated control group. The egg counts per gram of feces were determined by McMaster test on days 0, 3, 7, 14, 35, 56, 63, 70, 77, 84, 91 and 98 post-treatment (PT). Also, larval cultures were performed to identifying L3nematodes from the strongylida order by the Corticelli-Lai technique. IVM-3.15% and MOX-10% had similar efficacy (P < 0.001) from day 3 to 70 PT (100-75.7% and 100-93.1% respectively). MOX-10% showed greater persistence than IVM-3.15% at day 77 PT. The identified genera of nematodes from the strongylida order wereCooperia, Oesophagostomun, Ostertagia, HaemonchusandTrichostrongylus,the latter two being the most frequent. We conclude that IVM-3.15% and MOX-10% have good efficacy for controlling natural infections of GIN up to day 70 PT, and MOX-10% have greater persistence compared to IVM-3.15%, although its effectiveness was low at day 77 PT (40.8%). It is concluded that IVM-3.15% and MOX-10% subcutaneously have a good efficacy for controlling natural infections of GIN of the strongylida order. It was observed that MOX-10% have greater persistence than IVM-3.15% (93.1% and 75.7% of efficacy at 70 days PT, respectively), probably associated with the higher dose of MOX applied (1.6 times).  , Se evaluó la eficacia y persistencia de ivermectina-3,15% (IVM-3,15%) y moxidectina-10% (MOX-10%) contra infecciones naturales de nematodos gastrointestinales (NGI) en bovinos del trópico mexicano. Se utilizaron 33 bovinos hembras que fueron divididos en tres grupos de 11 animales recibiendo los siguientes tratamientos: grupo uno tratado con IVM-3,15% (0,63 mg/kg de pv) vía subcutánea, grupo dos tratado con MOX-10% (1,0 mg/ kg de pv) vía subcutánea, y grupo tres sin tratamiento (control). El conteo de huevos por gramo de heces se determinó mediante las pruebas McMaster los días 0, 3, 7, 14, 35, 56, 63, 70, 77, 84, 91 y 98 postratamiento (PT). Asimismo, se realizaron coprocultivos de larvas L3para la identificación de nematodos del orden strongylida mediante la técnica de Corticelli-Lai. La IVM-3,15% y MOX-10% presentaron eficacias similares (P > 0.001) del día 3 al 70 PT (100-75,7% y 100-93,1% respectivamente). La MOX-10% presentó mayor persistencia que la IVM-3,15% al día 77 PT. Los géneros de nematodos del orden strongylida identificados fueronCooperia, Oesophagostomun, Ostertagia, HaemonchusyTrichostrongylus,siendo los dos últimos los más frecuentes. Se concluye que la IVM-3,15% y MOX-10% vía subcutánea presentan buena eficacia para el control de infecciones naturales de NGI del orden strongylida. Se observó que la MOX-10% presenta mayor persistencia que la IVM-3,15% (eficacia de 93,1% y 75,7% a los 70 días PT, respectivamente), probablemente asociado a la mayor dosis de MOX aplicada (1,6 veces).