Bromatological value of Chironomidae produced from organic fertilizers and their effects on the growth of Clarias gariepinus fry in the Guinean forest region
摘要
The present study identified the most effective fertilizer based on the nutritional quality of Chironomidae (Chironomus sp, benthic macroinvertebrates) produced from organic fertilizer. The objective was to ascertain the most effective fertilizer based on the nutritional value of benthic organisms produced from cow dung, rabbit droppings, poultry droppings and pig manure. The experimental design consisted of 24 Chironomidae production ponds. Twenty-four rectangular ponds (1m x 1m) of approximately 1 m3 volume mounted in series, exposed to the open air. Each pond was filled 25 dm3 of substrate, fourty (40) liters of borehole water and immediately fertilized. The dose of 140 g/dm3 of different fertilizers was used for the production of freshwater genuine Chironomidae. The density of Chironomidae in the various production media was significant and found to be 2797 individuals/dm3, 2657 ind/dm3 for cow dung, 2573 ind/dm3 and 2432 ind/dm3 for rabbit droppings, cow dung, pig manure and poultry droppings, respectively. The evaluation of protein content of Chironomidae produced from cow dung, rabbit droppings, poultry droppings and pig manure resulted in 17.57%, 22.98%, 26.80% and 20.48%, respectively. The survival rates of Clarias gariepinus fry fed on Chironomidae produced from cow dung, rabbit droppings, poultry droppings and pig manure and treatment control (Coppens) were found to be optimal (94 ± 0.22), (92 ± 2.38), (95 ± 0.73), (95 ± 0.76) and (95 ± 1.32) and significant, respectively, when compared to those fed on Coppens. Chironomidae with rate protein significant contents between 22 and 26% of rabbit droppings and poultry droppings, respectively, with levels of liposoluble and water-soluble vitamins can substitute imported feed at the first stage of fry.