Evaluation of cockroach (Periplaneta americana) powder as a potential feed ingredient for ruminants: chemical composition, fatty acids profile and ruminal degradability

This experiment was aimed at determining the chemical composition, fatty acid (FA) profile and degradability of American cockroach (Periplaneta americana) powder (ACP) in comparison with soybean meal (SBM), fish meal (FM), and poultry byproduct meal (PBM). The cockroaches were stored for 2h at -20 ºC, transferred to liquid nitrogen and subsequently grinded. Other samples were dried at 60 ˚C for 48 h. Experimental diets were: (1) control diet (only SBM), 2) diet containing 3% FM, 3) diet containing 3% ACP, and 4) diet containing 3% PBM. Two fistulated Holstein heifers were used for estimation of the ruminal degradability of protein sources and experimental diets. The results indicated that the ACP contained 55.05, 24.55, 3.76, 8.68, and 5.60% crude protein (CP), ether extract, ash, and neutral and acid detergent fiber, respectively. The ACP was rich in monounsaturated and polyunsaturated FAs. There were significant differences in dry matter (DM) and CP degradability among protein sources. The degradability of soluble fraction (a) of SBM and ACP was significantly higher than other protein sources. The potentially degradable DM (b) for SBM was significantly higher. The CP washable fraction ‘a’ was significantly higher for FM and PBM. In contrast, the SBM contained larger ‘b’ which was smaller in FM and PBM. The estimated effective degradability of CP at all rumen passage rates was significantly higher in ACP than other protein sources. No significant differences were observed between the experimental diets in DM degradability coefficients (a, b and c). The control and ACP diets contained higher CP fraction ‘b’ than PBM diet. This experiment clearly showed that the ACP can be a good source of protein and mono-unsaturated fatty acids for ruminants.