Dietary black soldier fly as suitable ingredient for Muscovy duck: preliminary results on carcass and breast meat traits

Many studies have been conducted in poultry to substitute the conventional protein sources (fishmeal and soybean meal) with insect meals, due to their high protein content and the good and balance amino acid profile. The aim of this study was to evaluate the effect of dietary administration of a partially defatted black soldier fly larva (BSF) meal on carcass characteristics and breast meat quality in Muscovy duck (Cairina moschata domestica). A total of 256 females broiler Muscovy ducklings (average live weight, LW: 71.32±2.70g) were randomly allotted in 32 pens (8 replicates/treatment) and reared from day 3 to day 48. Four isonitrogenous and isoenergetic diets were formulated with increasing inclusion level of BSF (0, 3, 6 and 9%; BSF0, BSF3, BSF6 and BSF9, respectively) in substitution of corn gluten meal and divided in 3 feeding phases: starter (1-14d), grower (14-35d) and finisher (35-48). At day 48, 2 animals/ replicate were slaughtered and dissected to determine their carcass yields. The weights of spleen, bursa of Fabricius, liver, heart and abdominal fat were recorded. Breast and thigh muscles were then excised from 16 ducks/treatment and weighted. Ultimate pH (pHu) and L*, a*, b* colour values were then measured on breast muscle. Data were analysed by one-way ANOVA evaluating the effect of dietary BSF inclusion level by polynomial contrasts. Significance level was set at P<0.05. No significant difference was observed for final LW (2515.68±92.42g on average) among groups. Hot and cold carcass weights showed a quadratic response (P<0.05) to increasing BSF larva meal, with a minimum corresponding to BSF6; however, refrigeration losses were not affected by treatments (2.01±0.08% on average). No significant effects, related to BSF meal utilization, were observed for the weights of spleen, bursa of Fabricius, liver and heart. The weight of abdominal fat showed a quadratic response to increasing BSF larva meal with a minimum corresponding to BSF6 (P<0.05). Breast and thigh yields did not differ among groups (20.37±0.21% and 29.53±0.53% on carcass weight, respectively). As well, pHu and L*, a*, b* colour values were not different among groups. The obtained results showed that the inclusion of BSF meal, with the exception of BSF6, did not affect carcass characteristics and meat traits, confirming the potentiality of BSF meal in Muscovy duck.