Effects of Dietary Inclusion Level of Microwave-Dried and Press-Defatted Black Soldier Fly (Hermetia illucens) Larvae Meal on Productive Performance, Cecal Volatile Fatty Acid Profile, and Egg Quality in Laying Hens

Abstract

Black soldier fly (Hermetia illucens) larvae meal (HILM) is a promising alternative to soybean meal (SBM). However, little information is available on the effect of microwave-dried HILM as a dietary protein source in the diets of laying hens. We studied the effect of dietary inclusion level of microwave-dried HILM on productive performance, cecal volatile fatty acid profile, egg quality, overall fatty acid profile, and heavy metal residues of the egg in laying hens. A total of 144 laying hens (25-week-old) were randomly assigned to three dietary groups (eight replicates and six birds/cage): a control diet, and two experimental diets in which SBM was replaced with 2% HILM (2HILM) and 4% HILM (4HILM). The laying hens that fed the HILM showed satisfactory results in productive performance and egg quality. Branched-chain fatty acid levels increased linearly (p < 0.001) with dietary treatment in the cecal digesta. Total monounsaturated fatty acid increased linearly (p < 0.01), while total polyunsaturated fatty acid decreased linearly (p < 0.01) in the eggs by dietary treatments. Heavy metals, magnesium, zinc, and aluminum were increased linearly with dietary treatment; however, undesirable heavy metals were under permissible levels. Thus, microwave-dried HILM could be a possible alternative to SBM in the diets of laying hens; however, improvements in fatty acid profile are needed.

Black soldier fly (Hermetia illucens) larvae oil as an alternative fat ingredient to soybean oil in laying hen diets

“…The weight did not significantly differ among the three groups. However, HILM negatively affects productive performance in terms of lay percentage, feed intake, egg mass, and FCR in laying hens [ 17 , 28 , 29 ]. The decreased feed intake in laying hens fed with HILM can be explained by the dark color of HILM [ 8 , 28 ].…”

“…Furthermore, smell differences due to lipid oxidation caused by processing HILO at high temperatures can decrease feed intake in laying hens [ 8 ]. We extracted oil from dried larvae using a cold press, which has the advantages of preventing oxidation reactions, denaturation, and nutritional loss caused by heat [ 17 , 30 ]. Hence, cold-pressed HILO is a suitable fat ingredient in laying hen diets as it does not affect productive performance.…”

“…Three eggs per cage were homogenized (eight replicates/group) to analyze proximate composition according to the AOAC procedure [ 23 ], cholesterol levels using gas chromatography (GC) as described [ 24 ], and FA profiles as described [ 17 ]. Total lipids were determined as described by Folch et al [ 25 ], and the methyl esters of lipids were measured using a Star 3600 GC instrument (Varian Technologies, Palo Alto, CA, USA) with an Omegawax 205 Fused Silica Capillary GC Column (30 m×0.32 mm×0.25 μm film thickness).…”

“…In contrast, PUFA content is decreased in breast and leg meat of broilers fed with HILO [ 7 , 11 ]. Eggs from laying quails fed with a diet containing 10% H. illucens larvae meal (HILM) had similarly higher SFA and MUFA contents than control eggs [ 16 ], and laying hen diets containing 4% HILM increase the MUFA and decreased the PUFA contents in eggs [ 17 ]. In contrast, others have found no changes in total SFA, MUFA, or PUFA contents in eggs from laying hens fed with 5% HILM [ 18 ].…”

Italian Consumers’ Readiness to Adopt Eggs from Insect-Fed Hens

“…A significant further increase in soybean production will not be possible in the future because this crop requires large arable land and water supplies; moreover, the soybean used in animal feed is in direct competition with the same product for human consumption [17]. A number of studies have investigated alternative feeding sources for laying hens, including some that approach the concept of insect-based feed [18,19]. The main qualitative differences between eggs produced through insect-based feeds and eggs produced through regular feeds were in terms of shell thickness and yolk color [20,21].…”