ENHANCING SUSTAINABLE FEED PRODUCTION: UTILIZING AGRICULTURAL WASTES AS SUBSTRATES FOR BLACK SOLDIER FLY LARVAE CULTIVATION

Black soldier fly larvae (Hermetia illucens, BSFL) have garnered significant attention as a sustainable feed option due to their ability to grow on a wide variety of organic substrates, including agricultural byproducts, and convert them into nutrient-rich insect biomass. This research thesis comprises two independent studies aimed at utilizing two different organic substrates to cultivate BSFL. The first study investigated the utilization of Fusarium-damaged wheat kernels (FDK) as a feed substrate for BSFL. FDK, typically unsuitable for human or animal consumption due to the presence of harmful mycotoxins such as deoxynivalenol (DON), was hypothesized to support BSFL growth without adverse effects on feeding behaviour or development, with minimal mycotoxin accumulation in their biomass. To test this hypothesis, three FDK-based diets with varying DON concentrations were formulated alongside a 0 DON control diet. A preference test was conducted to observe BSFL behaviour towards the prepared diets. The results indicated that the DON concentration in the feed did not influence BSFL feed behaviour. Over a 15-day feeding period, DON accumulation in BSFL biomass and its effects on growth and nutritional parameters were analyzed against the prepared feeds. The levels of DON in BSFL remained consistently low across all diets, averaging only 0.87 ± 0.10 ppm, even in the diet with the highest DON content of 6.83 ± 0.06 ppm. Moreover, BSFL fed on FDK-based diets exhibited improved growth by Day 15 compared to those on the control diet, with larvae weighing 185.0 ± 3.2 mg on the highest DON diet, while those on the control diet weighed 177.6 ± 4.2 mg. In conclusion, BSFL can be safely reared on FDK-based diets to yield protein-rich insect biomass with minimal DON concentration, suitable for industrial-scale sustainable feed production. The second study integrated solid-state fermentation (SSF) and canola meal to develop growing substrates aimed at enhancing the fatty acid profile of BSFL. While BSFL is acknowledged as a nutritious feed option, it typically lacks essential omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) found in fish meal, a popular albeit expensive alternative. Previous research has indicated that the fatty acid composition of BSFL can be influenced by feed substrates, prompting exploration into methods to increase PUFA content. SSF using oleaginous microorganisms capable of synthesizing various fatty acids emerges as a promising approach. This study aimed to introduce omega-3 and omega-6 fatty acids into BSFL biomass via SSF, using canola meal, a readily available substrate with low market value. SSF was carried out with oleaginous microorganisms, including Thraustochytrium sp. ATCC 26185, Yarrowia lipolytica ATCC 90812, Mortierella alpina NRRL 66262, and Aspergillus oryzae NNRL 32657, and the fermented substrates were utilized to feed the larvae. The findings demonstrate that SSF effectively altered the fatty acid profile of BSFL, resulting in increased PUFA concentrations in larvae grown on fermented canola meal substrates. Specifically, the larvae grown on feed fermented with Y. lipolytica had 13.4% PUFA (in crude lipid) compared to larvae grown on unfermented canola meal, which had 7.6% PUFA on day 10 of feeding. These results show that the fatty acid profile of the BSFL can be altered by employing different feed substrates.

Name thesis:degree_name

Master of Science (M.Sc.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Food Science

Grantor

University of Saskatchewan

Year dc:date.issued

2024

Author dc:creator

• Kumar, Vishvendra

Advisor dc:contributor.advisor

• Tanaka, Takuji

Committee members dc:contributor.committeemember

• Ghosh, Supratim
• Kutcher, Randy
• Newkirk, Rex

• Black soldier fly larvae
• feed
• Fusarium head blight
• canola meal
• fermentation

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10388/15893

OAI identifier oai:identifier

oai:harvest.usask.ca:10388/15893