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Animal agriculture is under pressure to increase efficiency, sustainability, and innovation to meet the demands of a rising global population while decreasing adverse environmental effects. Feed cost and availability are 2 of the biggest hurdles to sustainable production. Current diets depend on sources of grain and animal byproduct protein for essential amino acids which have limited sustainability. Insects have arisen as an attractive, sustainable alternative protein source for animal diets due to their favorable nutrient composition, low space and water requirements, and natural role in animal diets. Additionally, insects are capable of bioremediating waste streams including agricultural and food waste, manure, and plastics helping to increase their sustainability. The insect rearing industry has grown rapidly in recent years and shows great economic potential. However, state-of-the-art research is urgently needed to overcome barriers to adoption in commercial animal diets such as regulatory restrictions, production scale issues, and food safety concerns. To address this need, the USDA Agricultural Research Service "MINIstoc: Model for INsect Inclusion" project was created to bring together diverse scientists from across the world to synergistically advance insect meal production and inclusion in animal diets. Here, we provide a short review of insects as feed while describing the MINIstock project which serves as the inspiration for the Journal of Economic Entomology Special Collection "Insects as feed: sustainable solutions for food waste and animal production practices." [ABSTRACT FROM AUTHOR]

Over the past 2 decades, the potential of insects as food and feed has been recognized globally. Insects as feed ingredients can improve sustainability because of their lower greenhouse gas emissions and their potential to transform organic wastes into high-quality feed rich in nutrients. However, currently, the practical use of insects as food or feed is limited by the high costs of insect production. A great deal of effort is required to improve the rearing technology necessary to establish the principles of insect farming. Several insect species have become industrialized using existing methods of production. The most common industrialized insect species intended as feed and food include the yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae); the house cricket, Acheta domesticus L. (Orthoptera: Gryllidae); the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae); and the house fly, Musca domestica L. (Diptera: Muscidae). This review focuses on describing the existing rearing methods for these 4 insect species, which may provide a basis for future research to enhance insect production capabilities. [ABSTRACT FROM AUTHOR]

Insect manure or "frass" has emerged as an alternative nutrient source for alleviating the dependence on fossil fuel-based fertilizers, reducing food waste, and promoting food security. Yet, research on insect frass chemical composition is in its infancy. Here, we assessed the chemical properties of yellow mealworm (Tenebrio molitor L.) frass compared with poultry litter (PL). Insect frass was obtained from the National Biological Control Laboratory (NBCL; IF-L) and an insect-rearing company (IF-C). PL was collected from facilities in Arkansas (PL-AR) and North Carolina (PL-NC). Samples were analyzed for pH, electrical conductivity, macro- and micronutrients, heavy metals, pathogens, and indicator microorganisms. On average, insect frass had 43% and 47% higher C and N than PL, respectively (P  < 0.05). Considering a 5 mg/ha application rate, IF-C can supply 159 kg N/ha, twice the N supply of PL-AR (78 kg/ha). IF-L had a 53% higher P supply than PL-NC. Mean K, Ca, S, and micronutrient contents were higher in PL than in frass (P  < 0.05), whereas As, Cd, Cr, and Pb were nearly absent in frass. Chemical composition and pathogens in fertilizer sources were largely affected by insect-rearing substrate and supplements used in poultry and insect production. Insect frass utilized in this study had optimum C and N rates relative to PL, suggesting a promising soil amendment for improving soil health and C sequestration, thus contributing to sustainable agricultural intensification and reuse of food waste in circular economies. [ABSTRACT FROM AUTHOR]

Mycotoxins that contaminate grain can cause the devaluation of agricultural products and create health risks for the consumer. Fumonisins are one such mycotoxin. Produced primarily by Fusarium verticillioides (Hypocreales: Nectriaceae) (Nirenberg, 1976) on corn, fumonisins' economic impact can be significant by causing various diseases in livestock if contaminated corn is not monitored and removed from animal feed. Finding safe alternatives to the destruction and waste of contaminated grain and restoring its economic value is needed for a sustainable future. Safe reintroduction into the farm food web may be possible through a consumable intermediary such as insects. This study demonstrates the suitability of the house cricket, Acheta domesticus L. as an alternative protein source in domestic animal feed by quantifying fumonisin B1 (FB1) levels in their subsequent insect meal and frass. Small colonies of 2nd instar A. domesticus were reared to 5th instar adults on nutrient-optimized corn-based diets treated with 4 levels of FB1 from 0 to 20 ppm. Increasing levels of FB1 had no adverse effects on the survivorship or growth of A. domesticus. Insect meals prepared from A. domesticus had significantly lower levels of FB1, at 3%–5% of their respective diets, while frass did not differ significantly from their diet. The successful rearing to adulthood of A. domesticus on fumonisin-contaminated diet paired with lower levels of FB1 in their processed insect meal supports the idea that more sustainable agricultural practices can be developed through remediation of low-value mycotoxin-contaminated grain with safer, higher-value insects as livestock feed components. [ABSTRACT FROM AUTHOR]

The southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae), is a widely distributed pest of many economically important crops. Because of its economic impact, multiple examples of rearing methods and diets for N. viridula have been published. However, rearing this pest year-round consistently in all-vegetable diets has been challenging. Preliminary observations have shown that supplementing N. viridula diet with insect components improves the survival and reproduction of this insect. We hypothesized that taurine could be the nutrient present in insect components that was providing the benefits. Treatments consisting of three different watering regimes: 1) Reverse osmosis (RO) water only (W), 2) 2% taurine solution only (T), and 3) a choice between RO water and 2% taurine solution (T&W) were compared for their effects on life cycle and demographic parameters of N. viridula. Both taurine-containing treatments (T and T&W) resulted in a significant increase in nymphal and premating adult survival and egg viability as compared with treatment 'W'. Taurine supplementation did not have significant effect on fecundity and development time significantly increased in the 'T' treatment compared with W and W&T treatments. However, there were significant improvements in demographic parameters showing an increase in fitness levels after taurine supplementation. These results suggest that taurine is an important nutrient for N. viridula , which has been deficient in traditional diets consisting exclusively of vegetable components. Adoption of this new information will help to improve the survival of N. viridula in culture to facilitate this study to develop new methods for its control. [ABSTRACT FROM AUTHOR]

The study of inheritance of quantitative traits of high plasticity in insects has been limited. The heritability of larval development time and body weight in Tenebrio molitor L. was determined using the method of parent-offspring regression. The parental group of adults obtained from a cohort from one day of oviposition from a stock colony was divided into 28 class groups according to their larval development time and pupal weight. The progeny resulting from these parental classes was grouped in experimental units and allowed to develop to the pupal stage. Means of larval development time and pupal weight of the progeny were compared with their parental class levels using linear regression. The selection of larval development time and pupal weight in the parental classes had a significant impact on the means of larval development time and pupal weight of the progeny. The regression coefficients for larval development time and pupal weight were 0.626 ± 0.02 and 0.408 ± 0.02, respectively. These values represent the proportion of genetic determination of these two traits based on the principles of the method of parent-offspring regression. The apparent independence of larval development time and pupal weight based on their poor linear correlation is discussed. [ABSTRACT FROM AUTHOR]

Nezara viridula (L.) (Hemiptera: Pentatomidae), commonly known in the U.S. as the southern green stink bug (SGSB), is a cosmopolitan, highly polyphagous feeder that causes severe damage to a wide range of agronomically important crops such as fruit, vegetable, grain, tobacco, and cotton, throughout much of the United States, and is a global pest of considerable ecological, agricultural, and economical interest. During dissection of female Nz. viridula , conspicuous black and brown spots or lesions were observed on various internal organs. To determine the cause of these spots or lesions, tissues of fat body, spermatheca, ovaries, and ovulated eggs were collected from healthy and infected individuals. The gross morphology of the spots was characterized, and the microorganisms associated with the infection were identified by amplicon sequencing of the V4 region of the small subunit rRNA gene. The presence of a microsporidian pathogen Nosema maddoxi, Becnel, Solter, Hajek, Huang, Sanscrainte, & Estep (Microsporidia: Nosematidae) which has been observed on other species of stink bug, was evidenced for the first time. The characterization of the gross morphology of this associated microsporidian may enable more rapid determination of microsporidia infection in stink bug colonies and field populations. [ABSTRACT FROM AUTHOR]

Mortality caused by indirect exposure to Metarhizium brunneum and Beauveria bassiana (GHA and NI8) to the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), workers was evaluated. Groups of 50 workers were placed in one side of dual-box arenas. The opposite side of the arenas was lined with filter paper squares previously sprayed with unformulated purified spores (106 spores/ml) suspended in 0.2% Ethal TDA 3, HLB 8 of the three fungal strains, or untreated filter paper squares as the control. Daily observations were done for 1 wk to determine mortality. Dead ants from each treatment and control were collected, surface cleaned, and placed in PDA media and incubated at 27°C, 60% RH for 7 d to detect fungal growth. The presence of fungal growth in the dead ants confirmed that fungal spores infected workers while walking on the treated paper. In the M. brunneum and B. bassiana GHA treatments, 51.35 and 56.68% of the workers died, respectively, during days 1 and 2. However, only 9.47 and 35.96% of the mortality could be explained by fungal infection by M. brunneum and B. bassiana GHA, respectively. Most of the mortality observed in the B. bassiana NI8 treatment (84.48%) occurred later (between days 4-6) and most of this mortality occurring during day 4 (89.06%) could be explained by B. bassiana infection. Overall mortality was significantly higher in the B. bassiana NI8 treatment than the other two fungi tested and control. Potential application of these fungal strains for fire ant control are discussed. [ABSTRACT FROM AUTHOR]

Life-table analysis yielded demographic parameter values that indicate that Tenebrio molitor (L.) pupae are potentially more suitable factitious prey to mass-produce the predator Podisus maculiventris (Say) and are more suitable prey than the larvae. P. maculiventris developed faster (23.2 vs. 25.5 d), weighed more (females 80.9 vs. 66.6mg and males 64.7 vs. 53.7 mg), and had a higher survival rate (0.88 vs. 0.7), fecundity, and reproductive output (87.1 vs. 22.8 eggs/female) when reared on pupae compared with larvae of T. molitor. The total protein content and soluble protein content were significantly higher in pupae (60.2 and 23%, respectively) than larvae (53.1 and 14.4%, respectively). Lipid content was significantly lower in pupae (32.1%) than larvae (35.9%), and larvae had more polyunsaturated fatty acids (83.6 vs. 56.6 mg/g) and less oleic (0.1 mg/g) and steric (6.1 mg/g) acids than pupae (37.3 and 12.3 mg/g, respectively). The total sugar content was not significantly different between pupae and larvae. However, larvae had significantly more fructose than pupae, but pupae had more galactose, glucosamine, glucose, mannose, and trehalose than larvae. Differences in nutritional composition and its impact on predator demographic parameters are potential factors that make the pupal stage a better food source. [ABSTRACT FROM AUTHOR]

Crowding conditions of larvae may have a significant impact on commercial production efficiency of some insects, such as Tenebrio molitor L. (Coleoptera: Tenebrionidae). Although larval densities are known to affect developmental time and growth in T. molitor, no reports were found on the effects of crowding on food utilization. The effect of larval density on food utilization efficiency of T. molitor larvae was studied by measuring efficiency of ingested food conversion (ECI), efficiency of digested food conversion (EDC), and mg of larval weight gain per gram of food consumed (LWGpFC) at increasing larval densities (12, 24, 36, 48, 50, 62, 74, and 96 larvae perdm2) over four consecutive 3-wk periods. Individual larval weight gain and food consumption were negatively impacted by larval density. Similarly, ECI, ECD, and LWGpFC were negatively impacted by larval density. Larval ageing, measured as four consecutive 3-wk periods, significantly and independently impacted ECI, ECD, and LWGpFC in a negative way. General linear model analysis showed that age had a higher impact than density on food utilization parameters of T. molitor larvae. Larval growth was determined to be responsible for the age effects, as measurements of larval mass density (in grams of larvae perdm2) had a significant impact on food utilization parameters across ages and density treatments (in number of larvae perdm2). The importance of mass versus numbers per unit of area as measurements of larval density and the implications of negative effects of density on food utilization for insect biomass production are discussed. [ABSTRACT FROM AUTHOR]

Measurements of head capsule, mandible, metanotum, and body weight were done on larvae of Tenebrio molitor L. (Coleoptera: Tenebrionide) from the second to the last instar. Instar number varied from 14 to 18, but 15 or 16 instars were the most common. The value of dimensional measurements was evaluated as a tool for instar determination and to improve understanding of instar variation in T. molitor. Three methods of analysis were used, including discriminant, cluster, and frequency distribution analyses. Stepwise regression analysis was used to determine the optimal combination of dimensional variables. Head capsule width, left mandible length, and body weight at the beginning of stadia were the most significant variables impacting instar. Discriminant analyses of instar using these three variables resulted in 47.74% misclassifications, indicating a high degree of dimensional overlapping among instars. Dimensional overlap and variability increased in older instars. Cluster 15-group analysis using measurements of head capsule width and mandible length resulted in the lowest level of group variability; however, there was low degree of correspondence between cluster groups and instars. Frequency distribution analysis of head capsule width revealed 11 peaks, but only the early 8 peaks corresponded with observed instars. All three methods of morphometric analysis failed to identify all instars of T. molitor correctly. Frequency distribution analysis provided the best match, but only among instars 2 to 10. It appears that instar variation in the larval development of T. molitor occurs after the 10th instar. A model of T. molitor developmental plasticity is proposed. [ABSTRACT FROM PUBLISHER]

Nezara viridula adult coloration can vary, including a rare orange-colored type (i.e., N. viridula f. aurantiaca). In November 2015, three Nezara viridula males displaying orange coloration were found in an established colony in Stoneville, MS. The objectives of this study were to determine if alleles of these orange types conformed to the allele characteristics previously reported for N. viridula f. aurantiaca and to determine if there were any differences in reproductive output compared with the green-colored type. The three orange-type males were crossed with green-type females to produce a hybrid F1. The F1 progeny was allowed us to cross to produce an F2. The F2 progeny consisted of 672 green females, 351 green males, 298 orange males, and 0 orange females. These ratios did not differ significantly from the expected 50:25:25:0 ratios for a single recessive sex linked allele for color phenotype. The F2 cross of green females and orange males produced an F3 consisting of 345 green females, 346 green males, 100 orange females, and 85 orange males. These ratios also conformed to the expected ratios (0.375:0.375:0.125:0.125) with the exception of orange males, which numbers were slightly lower than expected. The pure orange type N. viridula produced significantly less egg masses (0.71±0.15) per day than green types (2.09±0.16) and their reproductive output, measured as net reproductive rate (Ro), was lower in orange (13.71) compared with green (20.67) types. [ABSTRACT FROM AUTHOR]

The tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), is a polyandrous species of economic importance on the American continent. This sexual behavior allows for the presence of multiple spermatophores inside a female and the possibility of different males fertilizing the female's offspring, which can make insecticide resistance management or sterile insect release programs particularly challenging. The presence of spermatophores in a female can greatly influence her behavior, physiology, and offspring production. The role that these reproductive structures have is directly influenced by their size and the amount and type of substances that they contain as they are passed into the fenmle during copulation. In this study, we investigated the role that male feeding has on mating potential, including the basic chemical composition and coloration of three sequentially produced spermatophores by male moths that were fed nothing, water, sucrose solution, or nectar. Male moth feeding had a direct influence on spernmtophore weight, which was used as an indicator of polyandrous behavior. Nectar-fed moths produced heavier spermatophores and copulated in greater proportion than moths exposed to the other treatments. The total sugar and protein content of spermatophores was not influenced by the type of male feeding. Red or pink spermatophores were more prevalent in the first-produced spermatophores, diminishing in proportion on the second, and increasing again on the third-produced spermatophore, but this coloration proportion was prevalent of males not fed or fed only water. There were no differences in the chemical composition of the different colored spermatophores. These results indicate that polygynous behavior on H. virescens can be influenced by the type of male feeding. [ABSTRACT FROM AUTHOR]

Heliothis virescens F. is an important polyphagous pest that can develop on >100 plant species, including 20 economic crops. Populations of this insect are believed to be locally maintained on a few crops and weed hosts in Washington County, MS. To find the intrinsic value of these plants for the development of H. virescens populations, we fed different laboratory and wild colonies with fresh and lyophilized plant tissue under a constant temperature. Development time of this insect under laboratory conditions varied up to 10 d between plant hosts and was dependent on the type of plant tissue provided: fresh or lyophilized. Life table parameters such as net reproductive rate, finite rate of increase, and generation time indicated that Trifolium repens, a wild host growing around agricultural fields year round, could be one of the most suitable local plant hosts for the development of H. virescens. Two species of Geranium, previously reported as the source of the first H. virescens generation in the region, had lower intrinsic value as a food source than did T. repens. Gossyipium hirsutum, perhaps the most important crop source of H. virescens in the region, produced low net reproductive rate and finite rate of increase parameters. Sampling conducted in agricultural fields during 2006 and 2007 found no larvae on the above mentioned wild hosts as it was previously reported. Results indicated that H. virescens populations in this region were not supported by the wild plant species growing around agricultural fields during the time when the survey took place. [ABSTRACT FROM AUTHOR]

The importance of lipids for queen fecundity and colony growth of Coptotermes formosanus Shiraki was studied. Groups of 100 incipient colonies of C. formosanus were reared on artificial diet containing nine different soy lecithin concentrations. Eggs were counted every 15 d for a 5-mo period at 27 ± 1°C, 93 ± 5% RH, and 0:24 h (L:D) photoperiod. Fecundity per queen was estimated using a developmental rate-based graphic integration technique. At the end of a 1-yr period, the progeny of each colony was counted and recorded. Analysis of variance showed significant differences in queen fecundity and hatched progeny in colonies raised on various diets. Single linear regression analysis showed a small but significant linear increase in queen fecundity and hatched progeny per colony with increasing lecithin concentration. Increase in lecithin concentration explained ≈2, 4, and 8% of the increase in queen fecundity of colonies surviving 6 mo and 1 yr and number of workers and soldiers in 1 yr-old colonies, respectively. This indicates that, although intake of lipids increases queen fecundity and colony growth of C.formosanus, other factors not measured in this study alone or in combination with lecithin play major roles. [ABSTRACT FROM AUTHOR]

Effects of the chitin synthesis inhibitors (CSIs) diflubenzuron, hexaflumuron, and lufenuron on the Formosan subterranean termite, Coptotermes formosanus Shiraki, primary reproductives were studied in the laboratory. Incipient colonies were established by collecting and pairing C. formosanus alates and placing them in dishes containing an artificial diet. Three groups of 56 colonies each were fed with a diet containing 10 ppm of one of each of the CSIs and were compared with a control group fed with an untreated diet. All eggs oviposited by treated young queens failed to hatch at the end of 6 mo. Estimated queen fecundity was significantly lower in the lufenuron treatment compared with the control group. Fecundity of hexaflumuron-treated queens did not differ significantly from that of queens from the control group and the other treatments. Adult mortality was significantly higher in the diflubenzuron and lufenuron treatments than in the control group at the end of 6 mo., but not in the hexaflumuron treatment. All the pairs died within 8 mo. in the diflubenzuron and lufenuron treatments, even after treatment was suspended at the end of 6 mo. Mortality in the hexaflumuron treatment was significantly higher than in the control group by the end of 9 mo. The three CSIs tested eliminated reproduction in C. formosanus by preventing egg hatching and induced adult mortality. Possible mechanisms by which CSIs induce termite adult death are discussed. [ABSTRACT FROM AUTHOR]

Presents a study the examined the nutritional ecology of the Formosan subterranean termite and its growth and survival of incipient colonies feeding on preferred wood species. Materials and methods; Overall growth and survival of incipient colonies; Food treatment effect on colony growth.

The efficacy of three chitin synthesis inhibitors, diflubenzuron, hexaflumuron, and chlorfluazuron, incorporated into a novel bait matrix to kill the Formosan subterranean termite, Coptotermes formosanus Shiraki, was evaluated in the laboratory. The bait matrix was significantly preferred by C. formosanus over southern yellow pine wood in a two-choice feeding test. Bait formulations containing 250 ppm of the three chitin synthesis inhibitors were presented to termite nests with 2,500 individuals (80% workers and 20% soldiers) in the presence of alternative food sources consisting of cardboard and southern yellow pine, Pinus taeda L., wood. None of the bait formulations were significantly repellent or feeding deterrent to the termite workers evidenced by the lack of full consumption of alternative food sources. All nests presented with the bait formulations died within 9 wk, whereas the control nests (bait with no chitin synthesis inhibitors) remained alive 6 mo after the end of the study. No significant differences in consumption were observed among the chitin synthesis inhibitor treatments. Importance of this study for the improvement of current bait technology is discussed. [ABSTRACT FROM PUBLISHER]

The feeding preferences of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were tested in three separate experiments on 28 different wood species. Experiment 1 was a multiple-choice test designed to test relative preferences among 24 wood species commercially available in New Orleans, LA. Experiment 2 was a similar study designed to test relative preferences among 21 wood species shown or reported to be unpalatable to the Formosan subterranean termite. Experiment 3 was a no-choice test to examine the feeding deterrence of the 10 least preferred wood species. Preference was determined by consumption rates. Birch (Betula alleghaniensis Britton), red gum (Liquidambar styraciflua L.), Parana pine [Araucaria angustifolia (Bert.)], sugar maple (Acer saccharum Marsh.), pecan (Carya illinoensis Wangenh.), and northern red oak (Quercus rubra L.) were the most preferred species by C. formosanus in order of consumption rate. All of these species were significantly more preferred than southern yellow pine (Pinus taeda L.), widely used for monitoring. Sinker cypress [ = old growth bald cypress, Taxodium distichum (L.)], western red cedar (Thuja plicata Donn), Alaskan yellow cedar (Chamaecyparis nootkatensis D. Don), eastern red cedar (Juniperus virginiana L.), sassafras [Sassafras albidum (Nutt.)], Spanish cedar (Cedrella odorata L.), Honduras mahogany (Swietenia macrophyla King), Indian rosewood (Dalbergia latifolia Roxb.), Honduras rosewood (D. stevensonii Standl.), and morado (Machaerium sp.) induced significant feeding deterrence and mortality to C. formosanus. The last eight species produced 100% mortality after 3 mo. [ABSTRACT FROM PUBLISHER]

Efforts to improve rearing conditions of Tenebrio molitor L. (Coleoptera: Tenebrionidae) for insect biomass production included selecting for larger size pupae. The effects of an 8-yr continuous selection of T. molitor pupae for larger size were studied. Data consisting of daily counts and weights of pupae were analyzed using regression to determine the effects of selection over time. A preliminary evaluation of food conversion, growth, fecundity, and larval survival was done to compare ancestral versus selected strains. A significant positive correlation was identified between pupal size and time indicating a significant increase in pupal size over time in the selected T. molitor strain. A preliminary comparison of ancestral and selected strains showed significantly larger pupal size, growth rate, fecundity, and efficiency of conversion of ingested food in the selected strain. However, the selected strain also showed significantly lower larval survival than the ancestral strain. The low larval survival impacted the overall productivity of the selected strain resulting in no significant differences in biomass production when compared with the ancestral strain. The potential of using selection to improve biomass productivity in T. molitor is discussed. [ABSTRACT FROM AUTHOR]