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There has been continuous and growing interest in edible insects. Worldwide, various levels of insect farming are emerging, ranging from small domestic farms to vertical farms reaching heights of 36 meters, accommodating several million growing insects. The appeal of insects lies in their ecological benefits, as they contribute to the valorization of underutilized organic residues while requiring minimal space and water. The selection of insect species is influenced not only by their biology and behavior but also by local preferences and customs, varying with the scale of production and geographical location. This review article aims to provide an updated overview of the main insect species produced across different continents, their current level of industrialization, and production prospects based on available literature.

L'acétylcholinestérase (AChE, EC 3.1.1.7) est une enzyme indispensable de la transmission synaptique cholinergique. Son inhibition par les organophosphorés et les carbamates est à la base de certains traitements insecticides et nématicides utilisés en agriculture. Les faunes sauvage (en particulier les poissons) et domestique sont exposées aux résidus des traitements anticholinestérasiques. La mesure de l'inhibition de l'activité AChE chez ces espèces est un marqueur fiable de l'exposition. Ceci est montré ici pour l'AChE de carpes exposées expérimentalement au carbofuran (carbamate). Nous présentons parallèlement des données sur le gène de l'AChE chez Danio rerio et sur les formes moléculaires de l'enzyme chez Danio, Cyprinus carpio et Oncorhynchus mykiss. Contrairement à ce qui est observé chez d'autres vertébrés, le gène d'AChE de Danio ne possède pas d'exon H et seules les sous-unités de type T ont pu être identifiées chez ces trois espèces. Des résultats préliminaires d'hybridation in situ sur les embryons sont présentés et nous discutons l'intérêt des expériences de transgenèse dans l'oeuf de Danio pour étudier d'éventuelles fonctions morphogénétiques de l'AChE au début du développement.

The inventory of pests occurring on Dacryodes edulis(Burseraceae) was carried out in rural areas in Gabon during 2009 and 2010. Yellow traps and visual observations were used to record weekly pests during the tree flowering stage, in five villages. Catches from yellow traps rose to 7,296 and 1,722 insect pests in 2009 and 2010, respectively, whereas records from visual observations corresponded to 1,812 and 171 insect pests in 2009 and 2010, respectively. During both years, abundance from traps and visual monitoring was significantly different between sampling sites (p< 0.05). The difference in pests’ diversity between sampling sites was not significant (p> 0.05) according to traps, but significant (p≤ 0.04) according to visual observations in 2010. Mecocorynus loripesChevrolat (Coleoptera: Cucurlionidae) attacked the stem of D. edulis, while Oligotrophussp. (Diptera: Cecidomyiidae), Pseudophacopteron serriferMalenovsky and Burckhardt (Hemiptera: Phacopteronidae), and Selenothrips rubrocinctusGiard (Thysanopera: Thripidae) attacked leaves. Pseudonoorda edulisMaes and Poligui (Lepidoptera: Crambidae) and Lobesia aeolopaMeyrick (Lepidoptera: Tortricidae) infested fruits and inflorescences, respectively. These insects are specifically linked to plant patterns, and their identification provided the first basic information for developing suitable strategies to control pests of D. edulisin Gabon, as well as in neighboring central African countries.

The tomato leafminer, Tuta absoluta(Lepidoptera: Gelechiidae), is now considered to be one of the most damaging invasive pests of tomatoes in the world. Tomato is regarded as the main host of T. absoluta, but the pest can also feed, develop and reproduce on other cultivated Solanaceae, such as potato (Solanum tuberosumL). In the present study, we examined the ability of T. absolutato develop on four commonly cultivated varieties of potato, under laboratory conditions. The survival rate of T. absolutadid not differ between the five tested host plants (tomato: Solanum lycopersicumcv. Moneymaker; and potato: Solanum tuberosumcv. Spunta, Charlotte, Nicola, and Bintje), but its development time (egg to pupation) was significantly affected. Compared to tomato, development times were longer on Bintje and shorter on Nicola, Charlotte, and Spunta. These results show the high capacity of T. absolutato develop on potato crops.

The Colorado potato beetle (CPB), Leptinotarsa decemlineata(Say), has been an important defoliator of potatoes for 150 years. Although the use of insecticides allowed drastic reductions of CPB populations, resistance development against active substances has been observed. In this context, biological control using predatory larvae of the lacewing may represent a good alternative. CPB egg and larval consumption rates have been evaluated for all Chrysoperla carnea(Stephens) instars for 24 h. While first and second C. carneainstars only consumed eggs (1.3 and 1.8), first (1.5 and 2.4) and second (0.6 and 0.8) CPB instars, third instar of lacewing consumed all CPB immature stages: 6.8 CPB eggs, 8.5 first, 4 s, 0.5 third and 0.1 fourth CPB instars. This third instar killed 4-fold more CPB larvae than other larval stages. Handling time for third instar lacewing has been evaluated at 52 min on first instar CPB, 102 min on second instar and 164 min on third instar. Our laboratory assays highlight a potential for lacewing larvae to control CPB immature stages with a greater efficiency on young CPB larval stages. Fields assays are however needed to confirm efficiency of this CPB natural enemy under field conditions.The Colorado potato beetle (CPB), Leptinotarsa decemlineata(Say), has been an important defoliator of potatoes for 150 years. Although the use of insecticides allowed drastic reductions of CPB populations, resistance development against active substances has been observed. In this context, biological control using predatory larvae of the lacewing may represent a good alternative. CPB egg and larval consumption rates have been evaluated for all Chrysoperla carnea(Stephens) instars for 24 h. While first and second C. carneainstars only consumed eggs (1.3 and 1.8), first (1.5 and 2.4) and second (0.6 and 0.8) CPB instars, third instar of lacewing consumed all CPB immature stages: 6.8 CPB eggs, 8.5 first, 4 s, 0.5 third and 0.1 fourth CPB instars. This third instar killed 4-fold more CPB larvae than other larval stages. Handling time for third instar lacewing has been evaluated at 52 min on first instar CPB, 102 min on second instar and 164 min on third instar. Our laboratory assays highlight a potential for lacewing larvae to control CPB immature stages with a greater efficiency on young CPB larval stages. Fields assays are however needed to confirm efficiency of this CPB natural enemy under field conditions.

After the emergence of bluetongue (BT) in Belgium in 2006, two types of entomological surveys were initiated, the one to identify the local vector species, and the other to study their population dynamics. In the vector study, Culicoideswere captured near farms with recently infected cattle or sheep; in the population study Culicoideswere captured in two meadows situated in the BT-affected region. A total of 130 pools of parous, non-blood engorged female midges (with a mean of 7.5 midges per pool) were analysed with real-time reverse transcription PCR (RT-qPCR) targeting bluetongue virus (BTV) segment 5. To ensure the RNA integrity of the samples, all pools were also tested in a second RT-qPCR targeting Culicoides18S rRNA, which served as an internal control. Seventeen pools with negative results for both 18S and BTV were excluded, most of which originated from the population survey. In the vector survey near outbreak sites, female midges of the obsoletuscomplex, including C. obsoletus, C. scoticus, C. dewulfiand C. chiopterus, dominated the black-light trap collections with 19 of 89 pools being BTV-positive. Moreover, all the collections from the vector survey included at least one positive pool of the obsoletuscomplex compared with only 20 collections (C. obsoletusC. scoticus) in the population survey. The current study also revealed the presence of BTV RNA in one of five pools of C. pulicarisfemales captured near recent BT outbreaks, suggesting that this species might have played a role in transmission. Finally, the use of RT-qPCR for the recognition of new potential BTV vector species and the impact of an appropriate monitoring method and internal control are discussed.

We carried out a cross-sectional study in 12 rural villages in order to identify the risk factors for Kashin-Beck disease in Tibet. Children aged 5–15 years (n=575) were examined and their corresponding houses were visited. Samples were collected in order to study fungal contamination of stored grain and the organic matter content of drinking water. Multivariate analysis was performed using logistic regression and population attributable fractions were computed to estimate the impact of each factor. The following variables were independently associated with the disease: age, gender, low socio-economic status, indicators of a poorly diversified diet, iodine deficiency and small water container size (with higher organic matter levels in small containers). Selenium deficiency was severe in all study subjects. The degree of fungal contamination of barley grain was related to the highest percentage of cases (65%) in a sample of the study population. Higher urinary iodine levels were not associated with decreasing prevalence rates whenAlternariasp. was isolated. The data that we report supports the hypothesis that Kashin-Beck disease occurs as a consequence of oxidative damage to cartilage and bone cells when associated with decreased antioxidant defence. Another mechanism that may coexist is bone remodelling stimulated by thyroid hormones whose actions can be blocked by certain mycotoxins. Nous avons réalisé une enquête transversale dans 12 villages ruraux afin d'identifier les facteurs de risque de la maladie de Kashin-Beck au Tibet. Les enfants âgés de 5 à 15 ans (n=575) et leurs maisons ont été examinés. La contamination fongique des céréales et le contenu en matières organiques de l'eau de boisson ont été étudiés dans des échantillons de la même population. L'analyse multivariée a été effectuée par régression logistique et les fractions attribuables ont été calculées afin d'estimer l'impact de chaque facteur. Les variables suivantes étaient indépendamment associées à la maladie: l'âge, le sexe, un bas état socio-économique, une alimentation peu diversifiée, la déficience en iode et une petite taille du réservoir à eau (présentant un contenu en matières organiques plus élevé). La déficience en sélénium était sévère chez tous les enfants de l'étude. Le degré de contamination fongique des grains d'orge expliquait le plus haut pourcentage de cas (65%) dans le sous-modèle mycologique. L'iode urinaire n'était pas associé à la maladie lorsqueAlternariasp. était isolé. Les résultats sont compatibles avec des dommages oxydatifs aux cellules osseuses en présence d'une défense antioxidante déficiente. Un autre mécanisme co-existant possible est le remodelage osseux de l'os stimulé par les hormones thyroidiennes qui peut être bloqué par certaines mycotoxines.

Kashin-Beck disease occurs in several villages of Tibet; however, its local importance varies greatly. The ecoclimatological as well as the phytogeographical framework of the studied area are presented. An ecological approach based upon the ethno-ecosystem concept was carried out in the vicinity of each village. This study identifies 18 vegetation units on a structural basis; they were named for the dominant plants of each unit. Half of them belonged to the aquatic milieu. The different factors controlling their distribution were also identified. Particular attention will be paid to the links between man and the environment, particularly regarding alternative food intakes and water supply access. La maladie de Kashin-Beck est signalée dans divers villages du Tibet; toutefois son importance locale varie grandement. Les cadres écoclimatologique et phytogéographique de la zone d'étude sont présentés. Une approche écologique, basée sur le concept de l'ethno-écosystème a été effectuée dans les environs immédiats de chaque village. Cette étude conduit à reconnaître 18 unités de végétation d'un point de vue structural; elles sont dénommées sur base de leurs plantes dominantes respectives. La moitié d'entre elles relèvent du milieu aquatique. De plus, les divers facteurs contrôlant leur distribution sont identifiés. Une attention particulière sera portée en ce qui concerne les liens existant entre homme et environnement, en particulier en ce qui concerne les nourritures alternatives et l'accès à l'eau.

In order to clarify the association between mycotoxin-producing fungi in food and Kashin-Beck disease (KBD), we examined the occurrence and contamination levels of fungi in samples of barley grain, from KBD-affected families and from unaffected families in endemic areas. A control area without the occurrence of KBD served as reference. The first results obtained in 1995 showed that total mesophilic fungal contamination of barley grain was consistently higher in families with KBD. Trichothecium roseum(Pers) Link ex gray, DreschleraIto and AlternariaNees ex Fr. were the three most common fungi significantly associated with KBD. In 1996 we again observed a significant difference between affected and non-affected families, especially with Trichothecium roseumand UlocladiumPreuss. On this basis, measures to prevent KBD were suggested and a preventive program has been set up since 1998 in 20 new villages. Afin de vérifier l'hypothèse d'une relation entre la contamination des aliments par des moisissures et leurs toxines, avec la maladie de Kashin-Beck, nous avons évalué l'occurrence et le taux de contamination fongique dans les grains d'orge. Les études ont été menées en zones endémiques, chez des familles affectées par la maladie et chez des familles non-affectées. Une vallée contrôle, non affectée, a servi de référence. Les premières données obtenues en 1995 montre que le taux de contamination totale des grains d'orge par les moisissures mésophiles est régulièrement plus élevé chez les familles avec KBD. Trichothecium roseum(Pers.) Link ex gray, DreschleraIto et AlternariaNees ex Fr. sont les trois fongus dont la présence est significativement corrélée avec la maladie. En 1996, nous avons à nouveau obtenu une différence significative entre les familles affectées et non affectées, particulièrement pour Trichothecium roseumet UlocladiumPreuss. Sur cette base, des mesures pour éviter le KBD furent suggérées et un programme préventif a démarré en 1998 dans 20 nouveaux villages.

A radiological study of osteoarticular changes in Kashin-Beck Disease (KBD) was undertaken on the appendicular skeleton in 105 patients with KBD, in 31 healthy subjects living in an endemic area and in 30 healthy subjects living in a non-endemic area. The bone age was delayed in all three populations with no significant difference between the three studied Tibetan populations. Radiological changes occur in 56% of patients with KBD, and are usually bilateral. An analysis of the distribution of lesions shows a proximo-distal gradient. The changes are more common in the distal aspect of the limb and the lower limb is involved more commonly than the upper limb. The foot and ankle are involved in 89.5% of cases. The radiological changes and their distribution might be explained by the hypothesis of inhibition of angiogenesis by mycotoxins, exacerbated by chemical and physical environmental factors. Une étude radiographique des lésions ostéoarticulaires produites par la maladie de Kashin-Beck (KBD) a été réalisée au Tibet sur le squelette appendiculaire de 105 patients atteints de KBD, de 31 sujets cliniquement sains vivant en région endémique et de 30 sujets en région non endémique. La détermination de l'âge osseux révèle un retard de la maturité osseuse dans les trois groupes. Les lésions radiologiques sont présentes dans 56% des cas cliniques de KBD et sont bilatérales dans presque tous les cas. Le nombre de lésions augmente vers la périphérie. Le membre inférieur est plus souvent atteint que le membre supérieur. Le pied et la cheville sont atteints dans 89.5% des cas présentant une lésion radiologique. Les lésions radiologiques observées et leur distribution pourraient être expliquées par une inhibition de l'angiogénèse aggravée par les facteurs environnementaux chimiques et physiques.

The contamination of drinking water by organic acids, selenium deficiency and the ingestion of fungal mycotoxins are the three main aetiological factors in the development of Kashin-Beck disease. An avian tibial chondrodysplasia induced by mycotoxins has been reported. Deoxynivalenol (DON) is one of many mycotoxins produced by the most common contaminating species of fungi. The pattern of skeletal malformations induced by its administration intraperitoneally to pregnant mice is reported. Costo-vertebral segmentation abnormalities were the main deformities observed. The chondrodysplasia previously described was not seen. La contamination de l'eau potable par des acides organiques, une déficience en sélénium et une intoxication par des mycotoxines sont les trois principaux facteurs etiopathogéniques proposés dans la maladie de Kashin-Beck. Une chondrodysplasie tibiale a été décrite chez l'Oiseau. Elle était provoquée par des mycotoxines. Le désoxynivalenol (DON) est une mycotoxine communément produite par divers taxons de champignons qui contaminent les céréales et la nourriture. L'administration intrapéritonéale de DON à la souris gestante a provoqué des malformations squelettiques diverses. Les anomalies de segmentation costo-vertébrales sont les plus fréquentes dans le cadre du schéma choisi d'administration de la drogue. Nous n'avons pas pu reproduire dans cette étude préliminaire un syndrome de chondrodysplasie tibiale analogue à celui décrit chez l'Oiseau.

Competition between different males' sperm for the fertilization of ova has led to the evolution of a diversity of characters in male reproductive behaviour, physiology and morphology. Males may increase sperm competition success either by enhancing the success of their own sperm or by negating or eliminating the success of rival sperm. Here, we find that in the flour beetle Tribolium castaneum, the second male to mate gains fertilization precedence over previous males' sperm and fertilizes approximately two-thirds of the eggs. It is not known what mechanism underlies this pattern of last-male sperm precedence; however, the elongate tubules of the female sperm storage organ may encourage a ‘last-in, first-out’ sperm use sequence. Here we present an additional or alternative mechanism of sperm precedence whereby previously deposited sperm are removed from the female tract by the mating male's genitalia. In addition to providing evidence for sperm removal in T. castaneum, we also show that removed, non-self sperm may be translocated back into the reproductive tracts of new, previously unmated females, where the translocated sperm go on to gain significant fertilization success. We found that, in 45 out of 204 crosses, sperm translocation occurred and in these 45 crosses over half of the offspring were sired by spermatozoa which had been translocated between females on the male genitalia. In the natural environment of stored food, reproductively active T. castaneumadults aggregate in dense mating populations where copulation is frequent (we show in three naturally occurring population densities that copula duration and intermating intervals across three subsequent matings average 1 to 2 min). Selection upon males to remove rival sperm may have resulted in counter-selection upon spermatozoa to survive removal and be translocated into new females where they go on to fertilize in significant numbers.

Biological activity of leaves, fruits and extract of the African shrubBoscia senegalensis (PERS.) LAM. ex Poir. was evaluated against five stored-grain insects. When added to cowpeas at 2–4% (w/w), fresh ground fruits and leaves caused 80–100% mortality inCallosobruchus maculants (F.) adults and significantly reduced both emergence and damage of the F1 progeny. Acetone fruit extract exhibited a potent fumigant effect onProstephanus truncatusHorn, C.maculatus, andSitotroga cerealella OLIV.; with LT50 values of 3.8, 2.3, and below 1.5 hr, respectively. LC50 determination forB. senegalensis fruits and leaves as well as pure methylisothiocyanate (MITC) onTribolium castaneum HERBST,Sitophilus zeamais MOTSCH. andC. maculatus showed a differential response of the insects to plant parts or MITC. Quantitative dosage ofBoscia active components and LC50 values obtained for the plant tissues, compared to those of pure molecules, indicate that the biological activity ofB. senegalensis is due to the liberation of MITC from a glucosinolate precursor glucocapparin contained inBoscia fruits and leaves.

Different pairs of oligonucleotide primers have used for the detection of DNA polymorphism between Tribolium castaneum strains. Amplification of a major DNA fragment and two minor was observed in all strains tested excepted for one strain from France which present only two major bands (respectively at 800 bp and 880 bp). Arbitrarily, the major band amplified from a DNA sample of the strain originating from the Philippines was choosen as a probe (sequence of 487 bp in length). The combination of this probe and restriction enzymes permitted the discrimination between strains. Our results show that RAP marker of Tribolium castaneum could be used to study its population genetics.

Mycotoxins are naturally occurring toxic chemical compounds produced by fungi infesting agricultural crops both during their growth and storage. Such secondary metabolites, when ingested, can produce toxic syndromes in humans. As it has been suggested that mycotoxins might be involved in the development of Kashin-Beck disease (KBD), we undertook a survey of barley grains of KBD-affected families and non-affected families in that country. We found, by thin layer chromatography, a hitherto unknown metabolite of Alternariasp. This was especially common on the barley grains of KBD-affected families. Les mycotoxines sont des métabolites secondaires produits des champignons infestant les céréales au cours de la période culturale ou durant le stockage des grains. De telles substances chimiques peuvent être toxiques vis-à-vis de l'homme lorsqu'elle sont ingérées. La contamination des grains de céréales par des mycotoxines constitue toutefois une piste sérieuse pour la compréhension de l'étiologie de la maladie de Kashin-Beck. Nous avons entrepris des analyses de plusieurs mycotoxines sur des échantillons de grains d'orge provenant de familles malades et de familles non malades au Tibet. Un métabolite, encore inconnu, produit par Alternariaspp. a été détecté dans les échantillons de grains provenant des familles malades.

Dr. Marcel Leclercq was a pioneer in the field of forensic entomology. He has provided his knowledge of insect biology to many forensic cases, and most of them have found the way to publication. Most of the articles he has written were focused on individual cases, and despite the abundance of entomoforensic investigations he conducted, no synthesis has been published. This article summarizes 36 yr of forensic entomological investigations in temperate Europe, mainly in Belgium. Dr. Leclercq's work includes 132 entomological cases involving 141 human corpses found in various death scenes. Under certain conditions, insect specimens found at death scene can provide information on when (postmortem interval estimation), where and how a person died. More or less 100 insect species associated with a dead body have been identified by Dr. Leclercq.

Beekeepers suspected maize, Zea mays L., treated with imidacloprid to result in substantial loss of honey bee (Hymenoptera: Apidae) colonies in Belgium. The objective of this study was to investigate the potential impact of maize grown from imidacloprid-treated seeds on honey bee mortality. A survey of 16 apiaries was carried out, and all maize fields treated or not with imidacloprid were located within a radius of 3,000 m around the observed apiaries. Samples of honey, beeswax, and bees were collected in three colonies per apiary and analyzed for pesticide contain by liquid chromatography-tandem mass spectrometry and gas chromatography-tandem mass spectrometry. We first found a significant correlation between the number of colonies per apiary and the mortality rates in an apiary. In addition, this mortality rate was inversely correlated with the surface of maize fields treated and not with imidacloprid, suggesting that this pesticide do not interact with bees’ fitness. Moreover, a very large number of our samples contained acaricides either prohibited or ineffective against Varroa destructor (Anderson & Trueman) (Acari: Varroidae), suggesting that the treatment methods used by the beekeepers to be inadequate for mite control. Our results support the hypothesis that imidacloprid seed-treated maize has no negative impact on honey bees.