espanolEn la larvicultura de peces es necesario el manejo de la primera alimentacion para viabilizar las larvas para las etapas posteriores, siendo la densidad de siembra una variable importante en proceso de produccion de alevinos; por lo cual el objetivo del estudio fue evaluar el efecto de la densidad de siembra en la larvicultura de bagre blanco al inicio de la alimentacion exogena. Se evaluaron tres densidades de siembra: 100 (T1), 200 (T2) y 300 larvas/L (T3), alimentadas durante seis dias con zooplancton cultivado (Diaptomus sp, Diaphanosoma sp, Moina sp), ofrecido dos veces/dia; dos horas despues de la alimentacion se sifoneo y se cambio 40% de volumen de agua. Se utilizaron 18 acuarios de cuatro litros de volumen util, seis replicas por tratamiento, dispuestos en un diseno completamente al azar. Diariamente se realizaron mediciones de oxigeno disuelto, temperatura y pH; mientras que dureza, alcalinidad y amonio total se midio cada dos dias. Se estimo la ganancia en longitud (Gl), ganancia en peso (Gp), tasa de crecimiento especifico (G), sobrevivencia (S) y prueba de resistencia al estres (Re). A la menor densidad de siembra (T1) se obtuvo el mejor crecimiento (Gl=6.7±0.2 mm, Gp=7.4±3.9 mg y G=34.2±8.3 %/dia). Los valores promedios de S oscilaron entre 61.9 (T2) y 65.7% (T1) sin observarse diferencia significativa (p>0.05); igualmente en la prueba de Re no se observo diferencia significativa (p>0.05). En T3 se obtuvo la mayor productividad de larvas (186.3 larvas/L) y la menor en T1 (66 larvas/L), observandose diferencia significativa entre esos valores (p EnglishIn the larviculture of fish, it is necessary the handling of the first feeding to make the grubs viable for the later stages, being the thickness of sowing an important variable in process of production of fries; for which the target of the study was to evaluate the effect of the thickness of sowing in the larviculture of catfish target, at the beginning of the exogenous feeding. Three thickness of sowing were evaluated: 100 (T1), 200 (T2) and 300 grubs/L(T3), fed for six days with cultivated zooplankton (Diaptomus sp, Diaphanosoma sp, Moina sp), offered two times / day; two hours after the feeding, it was siphoned and 40% of water volume was changed. There were used 18 aquariums of four liters of useful volume, six copies by treatment, arranged in a design completely at random. Every day there were realized measurements of dissolved oxygen, temperature and pH; whereas hardness, alkalinity and entire ammonium was measured itself every two days. The profit was estimated in length (Gl), profit in weight (Gp), valuation of specific growth (G), survival (S) and endurance test to the stress (Re). To the minor thickness of sowing (T1) there was obtained the best growth (Gl 6.7±0.2 mm, Gp 7.4±3.9 mg and G 34.2±8.3 % / day). The average values of S ranged between 61.9 (T2) and 65.7 % (T1) and was not observed significant difference (p> 0.05); equally in the test of Re significant difference was not observed (p> 0.05). In T3 there was obtained the biggest productiveness of grubs (186.3 grubs/L) and minor in T1 (66 grubs/L), there being observed significant difference between these values (p