Feasibility evaluation for cockroach from Periplaneta americana as a new protein feed ingredient in pigs

Feed resources demand is globally increasing. The cockroach by-product from Periplaneta americana exhibits great potential as a new feed resource but lack of full-utilization. In this study, chemical composition, nutrient digestibility, energy utilization, standardized ileal digestibility (SID) for amino acids (AA) of full-fat cockroach (FFC) and unfatted cockroach (UFC) were evaluated, followed by the dietary feeding effects on growth performance of pigs. The results showed that both FFC and UFC contained high levels of crude protein (43.6% and 55.6%) with similar AA profiles to soybean meal. In addition, FFC-based diet had lower protein digestibility and energy utilization than UFC-based and soybean meal-based diets (P < 0.05), while no difference in protein digestibility was observed between the UFC-based and soybean meal-based diets. Except for histidine, proline and glycine (P < 0.05), the SID of AA did not differ between UFC and the control group, whereas FFC-based diet exhibited poor AA digestibility (45–55%). Furthermore, using 3% UFC to replace equivalent protein of soybean meal in the diet improved average daily gain (P < 0.05) and showed positive trends in elevating average daily feed intake and improving gain-to-feed ratio of finishing pigs. In conclusion, UFC demonstrated strong potential in replacing dietary soybean meal and improving growth performance of pigs, with high nutrient digestibility and SID of AA, whereas FFC is limited by its low nutrient digestibility. Our results provide great evidence for UFC from Periplaneta americana as a novel protein ingredient for swine nutrition.