Nutrient release characteristics of duck manure for Nile tilapia production
1989
Ullah, Amir Md.
Effect of duck diet, bedding material and manure storage on nutrient release characteristics of duck manure in water. A second experiment examined the effect of those factors on the suitability of duck manure for improving yields of Nile tilapia (Oreochromis niloticus). The first experiment was fresh manure of low and high grade diet with and without rice husk; the second one was four week old manure of the same low grade diet as used in the first experiment, except manure was stored under two different conditions and the third was four week old manure of high grade diet stored as in the second experiment. The accumulative ammonia-N released from manure in the first experiment varied from a minimum 6.5 mg/g dry matter (DM) to a maximum 9.2 mg/g DM and soluble reactive phosphorus (SRP) release varied from 1.7 mg/g DM to 2.0 mg/g DM. In second experiment, the accumulative ammonia-N release from manure varied from 7.0 to 8.8 mg/g DM and SRP release varied from 2.2 mg/g DM to 2.6 mg/g DM. In third experiment the release of ammonia-N range from 7.1 to 9.1 mg/g DM and the SRP release varied from 3.5 to 4.1 mg/g DM. Nearly all soluble nitrogen and phosphorus were released on the fourth day of manure application. The rate of nutrient release was increased by the improved diet manure and proper management of manure. Use of bedding material caused a reduction of the amount of nutrient release on a per unit weight basis. The improved manure obtained from high grade diet increased the fish yield but the use of bedding materiel did not effect the fish yield significantly
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