Nutritive Evaluation of Protein from Anaerobically Digested Poultry Wastes as a Dietary Ingredient Replacer for Channel Catfish, Ictalurus punctatus

Abstract

Two experiments were conducted to determine the effects of feeding protein derived from anaerobically digested poultry wastes on the performance of channel catfish. In the first experiment, poultry waste protein (PWP) was used as a substitute protein source at 5, 10, 20, 30, and 40% levels on an isonitrogenous and isocalorific basis, and compared to a control (0% PWP) soybean meal/fish meal‐based practical diet. A digestibility trial was conducted with diets containing 0, 5, 10, and 20% PWP. There were no significant differences in growth performance, feed efficiency (FE), protein efficiency ratio (PER), and protein productive value (PPV) of channel catfish fed up to 20% substitution compared to the control diet. At replacement levels of 30 and 40%, there were significant (P < 0.05) decreases in growth performance, FE, PER, and PPV. The apparent absorption efficiency was generally high for all the essential amino acids. Although differences in apparent crude protein and phosphorous absorption efficiency were not significant (P > 0.05), the coefficients were highest for fish that received recovered protein at 10% dietary level. It is concluded that up to 20% of protein derived from thermophilic anaerobic digestion of poultry wastes can be substituted without negative effect on performance.

Feed and Feeding Regime Affect Growth Rate and Gonadosomatic Index of Adult Zebrafish (Danio Rerio)

“…This cleaner environment would make the nutritional content of the feed fed to zebrafish more important as this environment would not be able to support the growth of bacteria capable of providing supplemental nutrition for zebrafish. Additional research would be needed to confirm this hypothesis, although the use of bacterial sources as feed supplements [39][40][41] or feed replacements [42][43][44][45] has been documented. It does appear, however, that Artemia enriched with spirulina powder was inadequate as a sole food source for rearing zebrafish.…”