Effect of the Incorporation Level of Ripe Avocado Pulp Powder Persea americana on the Zootechnical Performances of Clarias jaensis Juveniles (Boulanger, 1909)

Abstract

In order to contribute to the valorization of agricultural by-products in fish feed, the effect of the incorporation level of the ripe avocado pulp powder persea americana on the zootechnical performance of Clarias jaensis Juveniles (Boulanger, 1909), was studied between February and July 2019 in the highland zone of West Cameroon. To attend the aims, 156 juvenile Clarias jaensis (25.82 ± 7.43g) settled in triplicates in floating tanks were fed four iso-protein rations (40% crude protein) corresponding to 0, 8, 12 and 16% incorporation of ripe avocado. Feed were distributed twice daily (8 am and 6 pm) at 5% of the fish biomass for 63 days. The following results were as follows: Survival rate, final mean weight, daily mean weight gain, specific growth rate and condition factor K were higher and non-significant in batches receiving 8% of ripe avocado pulp powder with a lower feed conversion ratio (99,14 ± 0,50% ; 40,22 ± 10,5g; 0,14 ± 0,44 g/d, 0,41 ± 1,07 %g/d; 0,70 ± 0,09 %g/cm3 and 1,87 ± 0,09) and lower with a highest feed conversion ratio at 16% incorporation (93,67 ± 8,47 %; 30,02 ± 8,00g; 0,08 ± 0,22 g/d; 0,28 ± 0,77 % g /d; 0,68 ± 0,15 %g/cm3 and 2,018 ± 017). Body composition varied with the level of pulp meal incorporation, water content was high with 0% (79.14%), and dry matter (23.87%), crude protein (15.35%) and fat (5.23%). It was higher with 16%, while ash was higher (3.45%) in batches fed with 12% incorporation. The feed cost was lower at 8% incorporation (734.89Fcfa/kg of fish produced). The incorporation of 8% avocado pulp meal was found to improve the growth of Clarias jaensis juveniles and reduce the feed cost. Producers can use spoiled avocados as fish feed to reduce production costs, without negative impact on the final product.