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The earthworm Eudrilus eugeniae is a well-known source of protein in animal feeding but there is lack of information on its fatty acid profile. This study aimed to determine its nutrient components and fatty acid profile. Earthworms were bred in substrate containing organic matter; peanut powder was added in the experimental group diet. The nutrient components (protein, ash, and minerals) of the adult worms were determined according to the Kjeldahl method and by atomic absorption spectrophotometer. The fatty acid profile was determined by gas chromatography / mass spectrometry. The dry-matter protein content significantly increased in worms fed peanut powder (p < 0.05) as did the minerals measured. The main fatty acid families had similar proportions in the groups. In the saturated fatty acids, C12:0 and C18:0 were present in higher proportions in both groups, whereas in monounsaturated fatty acids, C18:1ω9 prevailed. Significant differences (p < 0.05) in polyunsaturated fatty acids were observed between the two groups. An increase in the proportion of ω6 and ω3 was observed in the experimental group compared to the control. This study showed that peanut powder significantly influenced nutrient components of E. eugeniae. The fatty acid profile of this species was similar to that of most animals. Earthworms’ diet can be altered to improve the nutritional value of E. eugeniae.

2,4-D is commonly used in the world to control undesirable plant species in monocotyledonous fields. The massive use of this herbicide requires knowledge of its ecotoxicological spectrum for better regulation of its use. This study aimed to characterize acute toxicity and to determine the long-term effects of a 2,4-D herbicide on Eudrilus eugeniae. The tests were carried out in Azaguié (Côte d’Ivoire), on natural soil enriched with rabbit droppings. The lethal concentration (LC50) was 175.6±12.3 mg/kg. The exposure of earthworms to 20 mg/l of 2,4-D (9.2 mg/kg) reduced significantly cocoon production, hatching rate and juvenile’s number per cocoon. With regard to these results, we concluded that 2,4-D based herbicides are potential threat to earthworms because CL 50 was largely below concentrations of 1920 mg/l and 2880 mg/l of 2,4-D recommended by the manufacturer.

In order to assess the effects of substrate on Eudrilus eugeniae production, 360 worms were raised in plastic buckets containing manure either from cattle (BV), from sheep (CM), from rabbit (CL), and from chicken (FP). At the end of the experiment which lasted 4 months, worm productivity was estimated at 111.9 g/kg of substrate in CL, 86.3 g/kg in CM, and 33.0 g/kg in BV. Substrate FP was inadequate as worms escaped from it. In another trial aiming at determining some of E. Eugeniae's reproductive parameters, each of the 3 substrates BV, CL, and CM was distributed into 15 plastic half bottles and was inoculated with one cocoon. In the 3 substrates cocoon incubation time and growing period were estimated at 3 to 4 weeks and 6 to 7 weeks respectively. Cocoons were laid approximately a week after the pairing of worms. On the average, each worm laid 2 cocoons per week.

Feeding Trials on Finishing Broilers Incorporating Earthworm Eudrilus eugeniae Meal. Seventy broilers of the "hubbard" breed raised in individual battery cages were divided equally into 2 groups R1 and R2 fed diets containing 5 % cow meat meal and 3.65 % Eudrilus eugeniae worm meal respectively. At the end of the experiment which lasted 4 weeks, both groups showed the same mean daily food consumption, mean daily weight gain, mean feed conversion, proportions of abdominal fat and carcass. The substitution ofmeat meal by worm meal was therefore considered efficient at the rates used.

The experiment shows that there is an optimal density to obtain the highest biomass when rearing hatchlings of Eudrilus eugeniae. Higher densities induce lower individual weight gain and longer duration to sexual maturity.