The unsustainable use of fish meals as protein and lipid
ingredients in aquafeed has driven the search for an
alternative. Black soldier fly (BSF) (Hermetia illucens) larvae
have been widely studied for substitution purposes. This study
aims at investigating the effect of solid fermentation of
pelleted diets containing BSF larvae meal (BSFLM) on the
growth performance of catfish Clarias sp. Four feed pellets
were formulated: F1 (non-fermented, 60% BSFLM), F2
(fermented, 60% BSFLM), F3 (non-fermented, 50% BSFLM),
and F4 (fermented, 50% BSFLM). These formulated diets and
commercial feed pellets (positive control) were separately fed
to the catfishes in 5 aquaria (10 fishes per aquaria in
triplicate). Results showed that the fermentation increased the
protein level by 10–11%, but kept the crude lipid
concentrations unchanged. Specific growth rate (SGR) and
weight gain (WG) profiles for fermented feeds F2 and F4 were
higher than the non-fermented feeds F1 and F3, respectively.
F4 gave the best feed conversion ratio (FCR) of 1.78, which
was 15–25% more efficient than F1, F2, and F3. Compared to
the commercial feed, the 4 formulated feeds underperformed
by around 50% in all of the growth parameters except survival
rates (SR) which were not significantly different (93–100%).
Nutritional value of black soldier fly (Hermetia illucens) larvae (BSFL) processed by three dif-
ferent methods of treatment was compared. The resulting products were the spray-dried
BSFL (SPR), oven-dried BSFL 1 (OVN1) and oven-dried BSFL 2 (OVN2). Proximate chemi-
cal composition, and profiles of amino acids, fatty acids, minerals, heavy metals, vitamins
and nucleotides were analysed and compared. The tested BSFL meals were considered to
have a good profile of essential amino acids (EAAs), with leucine, lysine, valine, and histi-
dine being the dominant EAAs. Their content of saturated fatty acids exceeded that of the
unsaturated fatty acids. Vitamins B1, B2, and C were also present in the samples. Minerals
such as calcium, potassium, phosphorus, sodium, magnesium, zinc, iron, manganese and
copper were found to be in adequate amounts in almost all the samples. Heavy metals in
the BSFL meals were mostly below 1g kg-1. Nucleotides such as inosine monophosphate
and uridine monophosphate occurred in all the BSFL meals. Other nucleotides, including
guanosine monophosphate, adenosine monophosphate, xanthosine monophosphate, and
cytidine monophosphate were detected in either or both of SPR and OVN2. In general, the
nutritional value of the BSFL meals tested in the present study was influenced by the
method of processing.