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The utilization of yellow mealworm, Tenebrio molitor(Linnaeus, Coleoptera: Tenebrionidae), for food and feed is gaining interest globally. However, its production is hindered by expensive commercial diets. This study assessed mealworm growth performance, survival, bioconversion, and nutritional composition when fed on wheat bran (WB) with different inclusion levels (25%, 50%, 75%, and 100%) of Irish potato waste (PW). Results indicated that mealworms fed on diets with 25%–75% PW had increased body length and 1–2 times higher weight gain compared to sole WB and PW diets. The survival rate was 93%–94% across all diets. Mealworms fed on WB had a feed conversion ratio of 3.26, while the efficiency of diet conversion increased with PW inclusion levels. Mealworms fed on diets with 75% PW inclusion had the highest crude fat (48%) and energy levels (598 kcal/100 g), while sole WB produced mealworms with the highest crude protein (55%). The acid detergent fiber achieved using 100% WB was 2- to 3-fold higher, but the crude fiber and neutral detergent fiber did not vary significantly. Considerable amounts of lysine (1.6–2 mg/100 g), methionine (0.5–0.7 mg/100 g), leucine (1.4–2 mg/100 g), and threonine (0.8–1 mg/100 g) were achieved in the mealworm larvae. Our findings revealed that cheap agricultural by-products could be successfully used for the mass production of mealworms, substantially contributing to reduced production costs. Further exploration of the nutrient-dense mealworm larvae for the development of novel food and feed products is crucial.

Rising feed cost challenges due to expensive conventional protein sources continue to make headlines in Africa causing drops in profit margins. We assessed the impact of insect (Hermetia illucensLinnaeus larvae meal, HILM) protein as a substitute for soybean meal and sunflower seed cake on layer chicken performance and profitability. Our results showed that apart from the growers, chicks (12.37 g/bird) and layer hens (2.02 g/bird) fed diets with 75% HILM inclusion levels had significantly higher average daily weight gain. The average daily feed intake (ADFI) and feed conversion ratio (FCR) varied significantly when the chicks and layer hens were provided with the HILM-based diets. For the chicks and layer hens, the lowest ADFI and FCR were observed in birds subjected to diets with 75% and 100% HILM compared to the growers fed diets with 50% HILM. Significantly higher egg production was observed for layer hens fed diets containing 75% of HILM throughout the first (87.41%) and second (83.05%) phase production cycles. Layer hens fed HILM-based diets had a 3–10% increase in egg laying percentage. There was higher profit margins when birds were fed diets containing 75% of HILM (~1.83 and 5.98 US$ per bird), which mirrored the return on investment estimated at 63.95% and 33.36% for the pullets (growers) and laying hen, respectively. Our findings demonstrate that diets with 75% HILM provided optimum growth performance, reduced feeding costs, increased weight gain and egg production as well as improved economic returns for commercial on-farm poultry production systems.

•Globally, saturniid caterpillars [e.g., G. belinaand G. maja] makeup 27.5% of caterpillars consumed.•In every 100 grams of dried G. belinaand G. maja, 73 and 61 grams constitute proteins, respectively.•G. belinaand G. majaare rich in lysine, methionine, omega-3 fatty acids, iron, zinc, calcium and vitamins.•The presence of flavonoids and phytosterols unravel additional health benefits of G. belinaand G. maja.•G. belinaand G. majashould be considered as functional ingredients in efforts to overcome food insecurity.

The prevailing global market demands locally produced, sustainable oils for biomedical applications. This study focused on evaluating the quality of cricket-derived oils and meals from Scapsipedus icipeHugel, Tanga, and Gryllus bimaculatusDe Geer common delicacy in Africa, following standard methods for physicochemical properties, fatty acid composition, and phytochemicals (oxalates, phytates, tannins, and polyphenols). The cricket oils physicochemical properties aligned with Codex Alimentarius standards for edible oils, including low solidification temperature (< 2 °C), a high refractive index (1.46), and a specific gravity of 0.88. Notably, peroxide values (1.9 to 2.5 mg mEq O2/kg), acid values (1.1 to 2.2 mg KOH/g), and saponification values (234–246 mg KOH/g) all are indicative of lightness and unsaturated fatty acids. Nutritionally, cricket powder was rich in protein (56.8–56.9% -) and fat (31.7–33.5% -of dry matter), with significant amounts of essential omega-3 and omega-6 fatty acids. Predominant saturated and monounsaturated fatty acids were palmitic (23.9–31.2 mg/100 g-) and oleic acids (10.9–11.4 mg/100 g- of oil), respectively. Antioxidant values (48.0 to 65.0 mg/100 g), inferred from total polyphenols, suggests a stable oil with long shelf-life. These results highlight the promising and sustainable potential of cricket-derived oils for applications in the food and pharmaceutical industries.

This study aimed to evaluate the performance of broiler chickens fed on 3 black soldier fly larvae (BSFL) (Hermetia illucens) and Greenleaf desmodium (Desmodium intortum)-based meals. We evaluated growth performance, carcass quality, and profitability under various commercial pathways (doorstep, retail, whole, and assorted). Desmodiumand BSFL powders were formulated into 3 ratios: T1 25:75, T2 50:50, and T3 75:25. A commercial feed was used as a control. One hundred and twenty mixed-sex 1-day-old broiler chicks (Cobb) were reared in pens for 42 d in a completely randomized design. The chickens were weighed weekly to monitor their growth rate. After the 42-day rearing period, they were slaughtered for carcass quality evaluation and recording of the weights of internal organs. During the initial growth phase (7–21 d), significant effects of fish meal replacement were found on the chickens' average weight (P < 0.001), average daily body weight gain (P < 0.001), average daily feed intake (P < 0.001), and feed conversion ratio (P < 0.001). However, during the second phase (21–42 d), no significant effect of the replacement was detected except on average daily feed intake (P = 0.003). No significant differences were found in terms of the relative weights of internal organs. It was found that Desmodium-BSFL-based feeds were more profitable than the control feed, and the assorted and retail modes of sale generated more revenue compared to when the chickens were sold at doorstep and on whole-chicken basis. The return on investment was higher for a push-pull adopter compared to a non-adopter. The study found that a BSFL-Desmodiummixture can be a valuable replacement for the protein component in conventional feed and would provide a new impetus for the adoption of push-pull.

There is a paucity of information on the edible grasshoppers and their host plants in East Africa. This study adopted morphological and molecular analysis to identify edible grasshoppers in Kenya and Uganda. The associated host plants were identified through molecular analysis of the gut contents of the grasshoppers. The cytochrome b and 16s gene primers were used for grasshopper DNA analysis; while matKgene primers were used for plant DNA analysis. All long-horned grasshoppers sampled were identified as Ruspolia differens(Serville) (Orthoptera: Tettigonidae); whereas short-horned grasshoppers were identified as Acanthacris ruficornis(Fabricius) (Orthoptera: Acrididae) and Cyrtacanthacris tatarica(L.) (Orthoptera: Acrididae). Host plants of A. ruficorniswere Achyranthes aspera(L.), Centella virgataL.f. Drude, Digitaria gayana(Kunth), Galinsoga quadriradiataRuiz and Pavon, and Triumfetta pilosaRoth; whereas those of C. tataricawere Alysicarpus rugosus(Willd.) DC and Teramnus uncinatus(L.) SW. Host plants of R. differenswere Ageratum conyzoides(L.), Citrus depressaHayata, Cynodon dactylon(L.), D. gayana, Eragrostis mexicanaHornem, Eucalyptus salignaSM., Indigofera arrectaHochst. ex A. Rich., Persicaria nepalensis(L.), and Sorghum halepense(L.). Information on the host plants of edible grasshoppers can help in the development of their mass rearing protocols.

Tuta absoluta(Meyrick) is one of the most devastating pests of tomato in both open field and greenhouse production settings that significantly reduce yield and quality of the fruit. Being a new invasive pest, information on the pest bio-ecology, including host-rage and effects of plant species on its various fitness traits are virtually lacking. This study involved a field survey to establish the realized host range and laboratory experiments to evaluate the preference for, and fitness effects of T. absolutaon different plant species. In the field, T. absolutawas recovered from only four solanaceous plant species: tomato (Solanum lycopersicumL.), eggplant (S. melongenaL.), black nightshade (S. nigrumL.), and gubbain (S. dubiumFr.). In choice and no-choice tests, tomato was the most preferred host of T. absolutahaving the highest number of eggs deposited, followed by black nightshade, French bean Phaseolus vulgarisL., and chilli pepper Capsicum frutescens. Larvae developed quickest on tomato followed by black nightshade and French bean. The percentage survival to adulthood was significantly higher on tomato, compared to survival on black nightshade and French bean. Rearing of T. absolutaon tomato or black nightshade had no significant effect on pupal mass and length as well as adult size for both sexes. Fecundity and longevity, as well as oviposition preference of T. absoluta, were not affected by rearing on different plants. These findings confirm the oligophagous nature of the pest with high preference to tomato.

Production of potatoes in the developing countries has been on the rise. This reinforces the growing importance of potatoes throughout Africa, Asia, and Latin America as a source of food and livelihood. However, this crop continues to experience major postharvest losses that are associated with a lack of effective storage facilities in these regions. This study used magnetic fields (MF) as an innovative technology to reduce potato losses while under storage. The effects of test variables; sources of magnetic fields intensity and exposure time on physicochemical properties of stored shangi potatoes were investigated. Double Helmholtz coils were used to generate MF. The coils were supplied with either direct current (DC) or alternating current (AC). Potatoes were then exposed to MF and stored in either the control or the commercial store. At the end of storage, physicochemical analyses were done following standard methods. AC MF resulted in significant (ρ < 0.05) higher specific gravity, dry matter, starch, and the number of sprouts per tuber but lower weight reduction, total sugars, reducing sugars, and non-reducing sugars than DC MF. Exposing potatoes to 3.00 mT of both DC and AC MF resulted in significant (ρ < 0.05) lower weight reduction, internal and external greening, sprouting, and the number of sprouts per tuber than in potatoes that were not exposed to MF. The current work has shown that it is possible to extend the shelf-life of the shangi potato variety by about 1 month, by use of MF, without compromising on quality parameters.

•Edible insects contained residues of 2 insecticides, 3 herbicides and 4 fungicides.•Contaminants in most edible insects were within maximum residue limits (MRL).•Some insects contained 2-49-fold higher pesticide residues than the MRL.•No residues were detected in the edible long-horned grasshopper, Ruspolia differens.•Edible insects should be farmed under regulated conditions to ensure safety.

•Insect farming is a novel and rapidly growing enterprise for protein and income in East Africa.•More than 80% of feed processors and farmers are willing to integrate insects in their livestock and fish feeds•Over 65% of those consuming insects as food would prefer processed flour to whole insect products•The economic viability of adopting insect-based protein is discussed.

Catches of Bactrocera invadens Drew, Tsuruta, & White (Diptera: Tephritidae) in Multi-lure traps baited with six commercial food-based attractants, Mazoferm E802, Torula yeast, GF-120, Hymlure, Biolure, and Nulure were compared in mango orchards in Kenya. In 2007, Mazoferm E802 and Torula yeast were the most effective attractants and captured 2.4–2.6 times more females and 3.4–4.0 times more males than the standard Nulure. All attractants captured more females than males (ranging from 63 to 74%). In 2008, Mazoferm E802 was the most effective bait capturing 5.6 and 9.1 times more females and males, respectively, than the standard Nulure. Among all the attractants, in both years, Nulure captured the greatest proportion of females: 74% compared with 51–68% for the other attractants. In 2008, the use of Mazoferm E802 in combination with spinosad as a bait spray in mango orchards reduced B. invadens catches relative to the control by 87% within 4 wk and 90% within 8 wk. At harvest, the proportion of fruit infested was significantly lower in the treated orchards (8%) compared with the control orchards (59%). Estimated mango yield was significantly higher in orchards receiving the bait sprays (12,487 kg/ha) compared with control orchards (3,606 kg/ha). Based on bait spray costs, yield data, and monetary gains, a cost–benefit ratio of 1:9.1 was realized, which is acceptable for growers. In 2009, the experiment was repeated with similar results. We have demonstrated that Mazoferm E802, used alone for monitoring of B. invadens or in conjunction with spinosad for population suppression, shows great promise in Kenya.