Quality and Fatty Acid Profile of Eggs as Affected by the Inclusion of Tenebrio molitor Larvae Meal in the Diet of Laying Hens

The study aimed to investigate the effect of the inclusion of Tenebrio molitor meal (TM) in the diet of layer hens on the quality characteristics of eggs and their fatty acid profile. A total of 90 layers (age 33 weeks) were involved in the trial. They were allocated to 5 dietary groups, each consisting of 6 replicate cages with 3 layers per cage. The layers were fed a basal diet (C) and diets including TM in amounts of 1% (T1), 2% (T2), 3% (T3), and 4% (T4) for a period of 10 weeks. The dietary incorporation of TM was associated with decreased weight of the eggs (p < 0.0001), albumen (p < 0.0001), yolk (p = 0.0008), and shell (p < 0.0001) as well as decreased shell thickness (p < 0.0001), corresponding to the deteriorated performance indicators. Additionally, the yolks of the hens receiving TM had a darker colour (p < 0.0001). The diets containing the insect meal led to significant decrease in the saturated (SFA) (p = 0.0019) and increase in monounsaturated fatty acids (MUFA) (p < 0.0001) in the yolks. The content of polyunsaturated fatty acids (PUFA) declined in the groups fed TM (p = 0.0028), particularly T3 and T4. This was, however, compensated by the favourably lower peroxidability (PI) (p = 0.0137), atherogenic (AI) (p = 0.0111) and thrombogenic (TI) (p = 0.0070) index and raised ratio between hypo- and hypercholesterolemic fatty acids (h/H) (p = 0.0039).