Hermetia illucens, is used as a reducing agent of palm kernel meal (PKM), as well as one of alternative protein sources for aquaculture purposes. Information about biology of H. illucens is absolutely required in mass production. The objectives of these researches were to study the development of H. illucens including the effect of supplementary food to the adult, and nutrient content of the immature stage. The sample of 20 larvae from each 3 replicates were measured and weighed on 0-19th day (larva) and 24th day (pupa) from egg hatching. H. illucens adults were fed by water and honey 5% (v/v). Eggs were collected and counted. Nutrient content of immature stage: 5, 10, 15, 20 days old (larvae), and 25 days old (prepupae) reared on PKM were analyzed proximately. Dry matter was determined by weight loss on drying at 105 oC during overnight. Crude protein was determined by Kjeldahl procedure (N x 6.25), crude fat by soxhlet (ether extract), crude ash by determining the residue after heating at 550 oC for 4–5 h. Data were analyzed descriptively by average from triplicate. The development of H. illucens was shorter than those in previous studies as the differences of abiotical factor. PKM was a suitable medium for development. It was better, however, to fed the adult with honey since it could enhance the fecundity. The young larva certainly contained the best quality of nutrition. To meet the quantity of mass production, however, the use of the elder larva (bigger) was suggested.

In intensive culture, the two species of brackish water tilapia, T. guineensis and S. melanotheron, have proved disappointing. Even under most favourable conditions, i. e. the monosex male culture of S. melanotheron, a poor growth rate (about O. 5g. d-') and a mediocre feed conversion do not presage a profitable aquaculture exploitation. On the other hand, extensive culture trials using the original "acadja-enclosure" technique have given very encouraging resu1ts.A nnual fish yields of more than 8 t/ha, including 70 to Sol ;/, of S. rnelanotheron of marketable size, are possible without any artificial feeding.

The morphological and physiological characteristics of the testes and the sperm of the catfish Heterobranchus longifilis (Val.) are presented. The effect of cryopreservation on the fertilizing capacity of the sperm was also evaluated. Testicular structure and spermatogenesis are described using histological techniques. The coexistence in the lobules of spermatozoa and all the spermatogenic stages indicates that this species is able to perform continuous reproduction. No seasonal trend was noticed in the evolution of the gonadosomatic index and in the quantity of the sperm produced over a year’period. However, maximum sperm production was observed in April and September. Different cryopreservation trials were conducted using a cryoprotective solution composed of 5% dimethyl sulphoxide (DMSO), 5% glycerol, 10% hen's eggyolk and 80% Mounib's solution. Fresh and cryopreserved semen gave equivalent hatching rates (81.1%, 83.4% and 78.9% respectively for the fresh, the 1‐hour cryopreserved and the 8‐month cryopreserved sperm). Percentages of normal and deformed larvae were not affected by sperm cryopreservation.

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Telah dilakukan penelitian tentang Palm Kernel Meal (PKM) yang difermentasi selama 7 hari secara alami tanpa penambahan inokulum yang hasil fermentasi disebut dengan PKMK. Produk fermentasi ditambahkan telur Hermetia illucens L. (maggot) diinkubasi selama 14 hari. Hasil penelitian menunjukkkan adanya kenaikan berat dan panjang maggot. Analisis proksimat menunjukkan kenaikan berat kering, nitrogen total dan serat, tetapi terjadi penurunan lemak dan abu.