Fresh oil palm mill effluent is fat-rich but its high moisture content makes it difficult to incorporate in standard poultry diets (Atuahene et al., 1987). Other limiting factors are the low protein and amino acid contents, and the high fibre content (Sinurat et al., 2000). As a consequence, relatively low amounts (5-15%) should be fed, depending on the process (fresh, dried, fermented), composition and poultry species.
In Ghana, a fresh (82% moisture) effluent with a particularly rich oil content (more than 70% DM) included at 5 or 10% (as fed) in broiler diets increased feed intake and growth performance (Atuahene et al., 1987). The same effluent, but sun-dried (11% moisture), mixed with rice bran was introduced at 10% in broiler diets without significantly affecting feed intake, weight gain and feed conversion efficiency (Atuahene et al., 2000).
In Indonesia, the best inclusion rate of dried palm oil mill effluent was 5% since 10-15% depressed feed intake (though without significantly affecting growth and feed conversion). Fermented palm oil effluent was included at up to 10% of the diet, as higher rates depressed growth (Sinurat et al., 2000). There was no advantage in feeding fresh rather than dried fermented effluent in both broilers and native chickens (Sinurat et al., 2001b; Sinurat et al., 2001c).
Replacing 20% of the maize energy in the diet (8% as fed) by a decanted (25% moisture) palm oil effluent was found to be economically beneficial (Bobadoye et al., 2006). A 7.5% inclusion rate also gave better growth and feed efficiency and was also economically viable (Kagya-Agyemang et al., 2008). However, this product impaired meat quality, as it decreased the proportion of lean meat and increased the lipid and cholesterol content, as well as its oxidative susceptibility vis-à-vis the accumulation of dangerous lipid peroxidation products (Onibi et al., 2011; Kagya-Agyemang et al., 2008).
Growing ducklings were found to be slightly more tolerant than broilers to dried effluent, and up to 15% (fermented or not) can be included in their diet (Sinurat et al., 2001a).