Effects of Organic Substrates on Development and Survival of Blattella germanica for Food and Feed in Kenya

Abstract

Entomophagy has gained popularity as a novel approach to addressing food and nutrition insecurity, particularly in sub-tropical and tropical countries. Cockroaches, for example, have the potential to alleviate nutritional deficiencies, as well as the erratic supply of protein in feeds. They can also be reared on locally available organic substrates. This study investigated growth performance and survival of german cockroach (Blattella germanica) reared on locally available organic matter substrates as treatments; spent brewers’ grain (Treatment A), Treatment B consisting of (40%: wheat bran: 40% spent brewers’ grain: 20% Caridina nilotica), wheat bran (Treatment C), and C. nilotica (Treatment D) and in a completely randomised design (CRD). Each treatment was replicated four times, while in each replicate 20 - 30 nymphs were reared for forty-two days. Feed intake for all the treatments was not significantly different. There was a significant difference (P < 0.05) in mature weight, average daily weight gain, live weight, and survival during rearing period. Cockroach performed well on treatment B and recorded highest mature weight, overall performance index, survival was 90.25 mg, 197.35, 96%. The least perfomance was reported in Treatment C; 1.78, 83, 143.17 and 72.5 for average growth rate, survival, overall perfomance and mature weight respectively. B. Based on these findings, a single feed as used in this study was inferior to the composite (Treatment B) in all parameters of growth performance and survival. The composite diet (Treatment B) could be suitable substrate for mass production of B. germanica for feed and food.