Replacement of Soybean Oil with Hermetia illucens Larvae Fat in Layer Diets: Effects on Performance, Egg Quality, Yolk Lipid Composition, and Ovarian Follicles

This study evaluated the effects of partially (50%) or completely (100%) replacing soybean oil with Hermetia illucens larvae fat (HI fat) in diets for laying hens on productive performance, egg quality, yolk lipid composition, and ovarian follicle characteristics during a 20-week feeding period. Sixty Lohmann LSL Classic hens were randomly allocated to three dietary treatments (Control, HI50, and HI100; n = 20 hens per treatment). Due to space limitations within the experimental facility, each treatment was housed in a single pen, which precluded statistical analysis of production performance data. Nevertheless, descriptive evaluation revealed no obvious differences in laying rate, egg weight, egg mass, feed intake, or feed conversion ratio among the dietary treatments. Most egg quality traits, including albumen height, Haugh units, shell strength, and yolk color, remained unaffected, although minor transient differences were detected at individual sampling time points. Dietary treatments altered yolk fatty acid composition, reflecting the fatty acid profile of the experimental diets. Replacement of soybean oil with HI fat increased the proportions of saturated fatty acids, particularly lauric (C12:0), myristic (C14:0), and palmitic acids (C16:0), while reducing both n-6 and n-3 polyunsaturated fatty acids. In conclusion, the findings of this exploratory study indicate that HI fat may have potential as an alternative lipid source in layer diets. Under the conditions of the present experiment, no obvious adverse effects on productive performance, egg quality, or ovarian follicle characteristics were observed. However, because each dietary treatment was represented by a single pen, the results should be interpreted with caution and require confirmation in studies with replicated experimental units.