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ADDITIONAL KEYWORDSBroiler performance. PALABRAS CLAVE ADICIONALESRendimiento del pollo. SUMMARYTwo hundred and sixteen unsexed day-old Cobb broilers of a commercial strain were used to study the effect of replacement of soybean meal (SBM) by cassava leaf:blood meal mix (CLM:BM) with or without enzyme supplementation on broiler growth and performance. The birds were divided into 6 groups of 36 birds each after balancing for live weight. Each group was further sub-divided into 6 replicates of 6 birds each. CLM:BM replaced SBM at 0, 25 and 50 % on weight for weight basis. The resulting three dietary combinations were supplemented with a commercial enzyme (Maxigrain ® ) at the rates of 0 and 100 ppm thus resulting in 6 dietary treatments. The six groups of 36 birds were randomly allotted to the six experimental diets. Feed and water were provided free choice during the 56 days experimental period during which data were collected on performance, nutrient retention, feed transit time and carcass characteristics of birds. Replacement of SBM with CLM:BM mix had no effect (p>0.05) on weight gain (WG), feed intake (FI), feed: gain ratio (F:G), crude protein (CP), ether extract (EE) and crude fibre retention (CF), dressing percentage, breast cut, drumstick, thigh liver and kidney weights but significantly (p<0.05) reduced intestinal transit time (ITT) and abdominal fat while increasing gizzard and caecum weight. Enzyme supplementation however significantly (p<0.05) improve WG and reduced F:G, improved (p>0.05) nutrient retention, dressing and abdominal fat percentage but had no effect on FI. No mortality was recorded in the course of this study. Enzyme supplementation significantly (p<0.05) reduced gizzard and caecum weights. It was concluded that in broiler feeding CLM:BM mix can effectively replace 50 % SBM without adverse effect on the birds. Supplementation of diets with enzyme led to further improvement in performance of broilers. RESUMENDoscientos dieciseis pollos Cobb, de un día, no sexados, fueron empleados para estudiar el efecto de la sustitución de la harina de soja (SBM) por una mezcla de hojas de yuca:harina de sangre (CLM:BM), con o sin adicción de enzimas, sobre el crecimiento y productividad de los broilers. Se formaron 6 grupos de 36 aves cada uno después de equilibrarlas en función del peso vivo. Cada grupo fue después subdividido en 6 repeticiones de 6 aves cada una. La mezcla CLM:BM se empleó para sustituir a la SBM en proporciones de 0, 25 y 50 % (peso/peso). Las tres combinaciones dietarias resultantes fueron suplementadas con un enzima comercial (Maxigrain ® ) en proporciones de 0 y 100 ppm resultando así 6 tratamientos dietéticos. Los seis grupos de 36 aves fueron aleatoriamente asignados a las seis dietas experimentales. El pienso y el agua fueron suministrados a voluntad durante los 56 días de periodo experimental durante el cual se obtuvieron los datos relativos a productividad, retención de nutrientes, tiempo de tránsito del pienso y caracArchivos de zootecnia vol. 62, núm. 238, p. 276. ADEY...