Feed & Additive Magazine Issue 2 March 2021

SPECIAL STORY FEED & ADDITIVE MAGAZINE March 2021 57 the question remains if we really want to have “vege- tarian predatory fish” like trout, salmon or seabass (still having in mind the BSE-disaster when real vegetarian animals were forced to become cannibals). As the ban on insect-based PAP (processed animal protein) for fish feeds was lifted in 2017 by the Euro- pean Commission the new insect-industry took-off in many European countries. Same happened in Asia and the Americas where research and industry, both display strong performance since then - as could be seen at the conferences on “Insects to feed the World” in 2014 and 2018. BSF-larvae meal is the most popular and most used insect-based feed-ingredient but, it has got one small disadvantage: It shows a high fat-content in the ma- trix (30 – 45%) depending on the given feed stock and the time of harvest. Therefore, BSF-meal needs to be defatted before being added to feed formulations. The fatty acid spectrum of the oil section is rather ad- verse and contains very little or no ω -6 and ω -3-fatty acids (which belong to the poly-saturated fatty acids, PUFA’s). If the BSF-oil is not or just partly extracted from the meal, the fat content in the fish and the sum of saturated fatty acids (SFA) will increase with increasing BSF-meal inclusion levels. The addition of macro- or micro-algae meal or -oil might be an alter- native to the use of fish-oil which is commonly used to reach high levels of PUFA’s in the fish fillet. The dietary inclusion level of BSF meal in carni- vore fish is reported to be best between 13 and 20%, but also minimum concentrations of 3 to 5% diet inclusion have been reported to result in decreasing feed conversion ratios in rainbow trout. On the con- trary there are also studies available reporting good results up to 40% with no negative effects on mor- phometric traits like growth rate, weight gain or feed conversion ratio. In general, meals from insects show different per- formances regarding growth and quality aspects in different animal species and reveal limited suitability as fish- and soymeal replacement in most cases, so far. ARE INSECTS SUSTAINABLE WHEN USED IN ANIMAL FEEDS? Still, it’s unclear which insect species will be the most suitable ones and to which extent fish meal, fish oil and/or soy bean meal can be substituted. The fi- nancial sustainability and the market competitiveness will need to be proved in the near future. With the argument of high fishmeal prices and a price plus that recognizes the environmental sustainability above fish meal and soybean meal, high prices for BSF meal were quoted in the past. The insect protein industry still has to fight with very high first costs - mostly due to immense investments and consequential high amortisations. It might be possible that BSF meal or house-fly-larvae meal can compete financially with “Mealworms” larvae from meal beetle Tenebrio molitor Author: C. Wehninger