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[Display omitted] • Silkworm excrement compost demonstrates high nutritional value with low heavy metal. • Silkworm excrement compost harbors rich eco-beneficial microbes. • K. pneumoniae and B. licheniformis synergistically contribute to plant production. • K. pneumoniae and B. licheniformis enhance animal production by degrading tannic acid. • K. pneumoniae and B. licheniformis play multifunctional role in recycling ecosystems. Sericulture has become widespread globally, and the utilization of artificial diets produces a substantial quantity of silkworm excrement. Although silkworm excrement can be composted for environmentally friendly disposal, the potential utility of the resulting compost remains underexplored. The aim of this study was to assess the quality of this unique compost and screen for eco-beneficial microbes, providing a new perspective on microbial research in waste management, especially in sustainable agriculture. The low-concentration compost application exhibited a greater plant growth-promoting effect, which was attributed to an appropriate nutritional value (N, P, K, and dissolved organic matter) and the presence of plant growth-promoting bacteria (PGPB) within the compost. Encouraged by the "One Health" concept, the eco-benefits of potent PGPB, namely, Klebsiella pneumoniae and Bacillus licheniformis , in sericulture were further evaluated. For plants, K. pneumoniae and B. licheniformis increased plant weight by 152.44 % and 130.91 %, respectively. We also found that even a simple synthetic community composed of the two bacteria performed better than any single bacterium. For animals, K. pneumoniae significantly increased the silkworm (Qiufeng × Baiyu strain) cocoon shell weight by 111.94 %, which could increase sericulture profitability. We also elucidated the mechanism by which K. pneumoniae assisted silkworms in degrading tannic acid, a common plant-derived antifeedant, thereby increasing silkworm feed efficiency. Overall, these findings provide the first data revealing multiple beneficial interactions among silkworm excrement-derived microbes, plants, and animals, highlighting the importance of focusing on microbes in sustainable agriculture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Diet and strain affect silk gland gene expression in the late fifth instar silkworm. • Diet affects fibroin-related gene expression in the middle silk gland. • Artificial diet upregulates the sericin gene in the posterior silk gland. The silkworm (Bombyx mori) is a model organism for lepidopteran insects. It is an oligophagous insect that primarily feeds on mulberry leaves and has industrial use for the production of raw silk. The development of artificial diets has provided an alternative nutrient source for silkworms; however, one significant issue is that the production of cocoons is lower in silkworms reared on artificial diets compared with those reared on mulberry leaves. The differences in the silk gland in the late-stage fifth instar silkworm larvae, when silk synthesis is most active, between those raised on artificial diets and mulberry leaves, are unknown. In this study, we identified differences in the transcriptomes of the middle and posterior silk glands of fifth instar day five silkworm larvae reared on artificial diets compared with those reared on mulberry leaves using three strains: Daizo, Nichi01, and J137 × C146. We found that the silk-related genes fibrohexamerin (fhx), fibroin-light-chain (fibL), and fibroin-heavy-chain (fibH) in the middle silk gland, and ser1 in the posterior silk gland, were differentially expressed in a strain-dependent manner. In silkworms reared on artificial diets, fhx , fibL , and fibH in the middle silk gland were upregulated in Nichi01 and downregulated in J137 × C146, whereas ser1 in the posterior silk gland was upregulated in J137 × C146 compared with silkworms reared on mulberry leaves. Our results demonstrate that the diet and strain of silkworm larvae affect the expression of genes related to silk production in their silk glands during the late fifth instar stage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A transcriptome database was created for young silkworms fed an artificial diet. • Abnormal expression of genes associated with growth and development was identified. • The causes for the impaired growth and development of the silkworms were proposed. To investigate the impact of different diets on the growth and development of the silkworm Bombyx mori (L.; Lepidoptera: Bombycidae), we conducted an analysis of differentially expressed genes (DEGs) between larvae fed an artificial diet (referred to as the AD group) and those fed mulberry leaves (referred to as the ML group) during the first, second, and third instars using RNA sequencing (RNA-Seq) technology. Our results revealed that the DEGs primarily belonged to pathways associated with lipid metabolism, carbohydrate metabolism, amino acid metabolism, the endocrine system, the nervous system, the digestive system, the immune system, and oxidation–reduction processes. Notably, in the AD group, there was a decrease in transcript levels of genes related to amino acid metabolism synthases, while the transcript levels of antimicrobial peptide genes were up-regulated. Furthermore, genes associated with cytochrome P450 (CYP) enzymes exhibited down-regulation in the AD group. These observed changes likely contributed to the delayed growth and compromised robustness observed in the AD group. Overall, these findings provided valuable insights into the mechanisms underlying the differences in growth, development, disease resistance, and adversity resistance between silkworms fed an artificial diet and those fed mulberry leaves. [ABSTRACT FROM AUTHOR]

Abstract Moina macrocopa (Straus, 1820), was cultured on different animal manures (i.e. chicken manure, Pig manure and cow manure) and food waste to detect the influence of these food sources on its mass production. Then M. macrocopa was used as feed for the rearing of Pagrus major larvae and its effects on their performance was studied. At first, the experiment was carried out for 21 days to identify the best culture medium for M. macrocopa. Food waste treatment resulted in higher density of M. macrocopa compared to other animal wastes. The percentage of unsaturated fatty acids was also significantly higher in the food waste treatment. Subsequently, we compared the effect of M. macrocopa cultured on food waste, Artemia and artificial diet on rearing the larvae of Pagrus major , red sea bream. The feeding time differed for each treatment, but the feeding number and amount were adjusted for all treatments. Results showed that larvae fed with M. macrocopa showed higher survival rates, growth rates, stress tolerance rate and DHA/EPA ratio than larvae fed with Artemia and artificial diet. The present results revealed that M. macrocopa cultured on food waste has an outstanding food potential and a probable substitute for Artemia. [ABSTRACT FROM AUTHOR]

Abstract The Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae) is an economically important pest of corn. Finding simple, cheap, and suitable rearing techniques of O. furnacalis is an urgent need to support research for management of this insect. This research aimed to determine the suitability of a read bean and rice bran-based artificial diet used for mass rearing of this insect since 2009. The tested artificial diet was compared with the natural diet (sweet corn kernel) and each diet was tested in individual rearing method (one larva in each vial). The criteria used to justify the quality of diet and mass rearing procedure were based on the fitness of O. furnacalis. The degree of fitness was based on life history, growth, and development. In general, the fitness parameteres observed from O. furnacalis reared in the artificial diet at 25.7 ± 1.6 °C with 57.7 ± 3.8% RH, and L12:D12 were similar than those in the natural diet. Therefore, the existing artificial diet and rearing procedure were considered suitable and qualified for O. furnacalis. It is important to periodically check the laboratory colony to ensure that they have similar fitness to those found in the natural population. Graphical abstract Unlabelled Image Highlights • In general, fitness of O. furnacalis reared using two diets was similar. • Rearing procedures used were suitable and qualified for O. furnacalis. • The artificial diet can be used for rearing O. furnacalis for different purposes. [ABSTRACT FROM AUTHOR]

The silkworm, Bombyx mori , is an important oligophagous economic insect and feeding habits of different silkworm varieties to artificial diet are different. Research on the mechanisms of feeding habits on artificial diet, and breeding of silkworm varieties adapted on artificial diet, which is a necessary condition for industrial silkworm rearing, is currently lacking. For an artificial diet, Xin was anorexic, whereas Haoyue A showed a strong appetite. When the two varieties were crossed, the F 1 generation showed a poor appetite for the artificial diet and had a setae dispersion rate of <50 %. However, the F 2 generation, self-bred progeny of F 1 , had a good appetite for the artificial diet, with a setae dispersion rate of 70 %. Herein, transcriptome analysis was conducted on the F 2 generation, comparing individuals with anorexic and preferred feeding habits, and 2188 differential genes were identified, with 1524 genes up-regulated and 934 genes down-regulated. Several genes were identified to contribute to feeding habits, such as genes involved olfactory system, energy supply, and cell proliferation and differentiation. GO enrichment revealed a large number of DEGs related to behavior, growth, signaling, developmental process, response to stimulation, and other pathways. Furthermore, proteins closely related to feeding were expressed differently. Some DEGs were selected for qRT-PCR, and results indicated the reliability of the DEG results. The DEGs between individuals with anorexic and preferred feeding habits were screened by RNA-Seq technology, which provides a reliable reference to study molecule mechanisms of feeding habits on artificial diet. We compared the different expression genes between anorexic individuals and preferred individuals to artificial diet. We annotated and classified these unigene sequences by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional classification. Significant differences and pathways may be related to feeding habit of silkworm to artificial diet were found in anorexic individuals. Our study provides basic data for the breeding of silkworm varieties adapted to artificial diet and insights into feeding habit mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

Different protein sources from plant and animal origin viz., soybean flour (SF-AD) and soaked soybean (SS-AD), bee pollen (BP-AD), honey bee drone larvae (DL-AD) and frozen aphids (AF-AD) were assessed as an artificial diet of C. septempunctata in comparison to their natural diet live aphids. Highest growth index was obtained with SS-AD (4.05) diet almost similar to control (4.0), followed by SF-AD, BP-AD, DL-AD and AF-AD as 3.8, 2.4, 1.98 and 1.94 respectively. Similarly, data showed that success index of the adults fed on an artificial diet containing soybean (SS-AD = 1.03, SF-AD = 0.98) was almost similar to control (1.0), whereas the diets containing bee pollen, drone larvae, and frozen aphids was lower than control as 0.83, 0.84 and 0.78, respectively. Protein concentration was highest in live aphid (5.9 μg/ml) diet followed by SS-AD (5.6), SF-AD (5.2), BP-AD (3.4), AF-AD (2.2) and DL AD (1.3). The results indicated that soybean based diets were more or equivalently suitable to beetles for their growth and development likewise their natural prey and the efficiency of artificial diets was related to its protein concentration. [ABSTRACT FROM AUTHOR]

The use of augmentative biological controls in greenhouse pest management has increased the demand for predators. To meet demands, suitable artificial diets must be developed to enable fast and cost-effective mass rearing of predators. In this study, three artificial diets were developed and their suitability for immature development and survival of Japanese ladybird Propylea japonica (Thunberg) and Multi-colored Asian ladybird Harmonia axyridis (Pallas) were investigated. An artificial diet composed of shrimp, beef, beef liver, and egg yolk in a 5:4:8:4 ratio is an adequate source of nutrition for the development of immature P. japonica and H. axyridis , resulting in 83% and 68% adult emergence rates, respectively. The reproductive performances of emerging P. japonica and H. axyridis females fed the artificial diet or pea aphids were compared. The pre-oviposition period was shorter in emerging females from immature ladybirds fed an artificial diet compared with those emerging from immature ladybirds fed pea aphids. However, the total fecundity did not vary significantly. When adults were fed artificial diets, females did not lay eggs, but oviposition could be restored by feeding adults on pea aphids. The developed artificial diet can be used for the mass rearing of P. japonica and H. axyridis for biological control applications and rearing of adults during prey shortage. [ABSTRACT FROM AUTHOR]

In Darjeeling Terai-Dooars, looper stage of Hyposidra infixaria is often causing heavy damage to tea crop as key pest. Therefore for conducting experiment related to its control, rearing on artificial diet becomes an imperative. H. infixaria showed better survival on modified artificial diet of its congener H. talaca than on tea-leaves used as natural diet. Shorter life-cycle, superior developmental traits, higher fecundity and better food utilization capability indicated suitability of the artificial diet. Activity of midgut amylase, protease and lipase of loopers provided suitable hint for formulating balanced artificial diet that supported its normal growth and development. This first attempt of rearing of the pest species ( H. infixaria ) through three consecutive generations on artificial diet could be useful in mass production of disease-free specimen for the purpose of research and development activity related to tea plant protection and industrial-level production of bioagents. [ABSTRACT FROM AUTHOR]

Aedes aegypti mosquitoes obtain from vertebrate blood nutrients that are essential to oogenesis, such as proteins and lipids. As with all insects, mosquitoes do not synthesize cholesterol but take it from the diet. Here, we used a chemically defined artificial diet, hereafter referred to as Substitute Blood Meal (SBM), that was supplemented with cholesterol to test the nutritional role of cholesterol. SBM-fed and blood-fed mosquitoes were compared regarding several aspects of the insect physiology that are influenced by a blood meal, including egg laying, peritrophic matrix formation, gut microbiota proliferation, generation of reactive oxygen species (ROS) and expression of antioxidant genes, such as catalase and ferritin. Our results show that SBM induced a physiological response that was very similar to a regular blood meal. Depending on the nutritional life history of the mosquito since the larval stage, the presence of cholesterol in the diet increased egg development, suggesting that the teneral reserves of cholesterol in the newly hatched female are determinant of reproductive performance. We propose here the use of SBM as a tool to study other aspects of the physiology of mosquitoes, including their interaction with microbiota and pathogens. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) is the most destructive insect pest of several palm species, worldwide. The maintaining of RPW laboratory colonies for experimentation has been very challenging. We synthesized a standardized semi-artificial diet which is easy to prepare and economical for the rearing of RPW. The effects of semi-artificial diet on biological traits related to RPW development were studied at the Economic Entomology Research Unit (EERU), Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia. The diet was synthesized by combining shredded date palm petiole tissues, corn flour, wheat flour, ascorbic acid, sodium benzoic, sorbic acid, agar, and distilled water. Three replicates, each containing fifty newly hatched larvae, were reared on the semi-artificial diet. The developmental time of RPWs fed on the newly synthesized diet was compared to the growth rate of conspecifics fed on date palm and previously published artificial diets. Fully-grown larval weight ranged from 4 to 6 g (5 ± 0.19 g), and larval duration ranged from 46 to 57 days (53 ± 0.3 days). Average adult emergence was 58–98 % (78 ± 0.6), with an average weight of 0.90 g for males and 0.97 g for females. Complete life span was between 48 and 98 days (77 ± 0.9 days). On present semi artificial diet, several larvae had 11 larval instars. The diet has a shelf life of at least seven days and can last up to two weeks if properly kept and saved. In conclusion, the present study proved that semi artificial diet is quite capable for the successful rearing of RPW. The growth and development of RPW larvae reared in this experiment were comparable to those fed on a natural diet. [ABSTRACT FROM AUTHOR]

[Display omitted] • Various body weight gain rates of Bombyx mori occur in response to variable food regimes. • Compensatory growth in Bombyx mori partially prevents body weight loss. • Compensatory growth affects digestive enzyme activities. • Digital gene expression profiling was used to analysis of differentially expressed genes. • Compensatory growth affects the gene expression levels of PI3K/AKT signaling pathway. Organisms achieve compensatory growth after a period of nutrient restriction followed by recovering the nutrient status. However, the underlying mechanisms associated with such growth acceleration remain unclear. The silkworm Bombyx mori is a lepidopteran model insect. This study aimed to investigate the physiological characteristics and the underlying mechanisms in B. mori fed on mulberry leaves (MG), artificial diet (AG), and artificial diet + mulberry leaves (AG-MG), respectively. Silkworms in AG-MG which fed on artificial diet from 1st to 3rd instars followed by feeding on mulberry leaves from 4th to 5th instars exhibited a higher weight gain rate than that in MG and AG, indicating that compensatory growth occurred as a result of the switch in the silkworm food regime. Trypsin and lipase activities of silkworms in AG-MG were shown to be up-regulated at 72 h after changing food. Digital gene expression profiling (DGE) analysis revealed that genes related to metabolism and development in silkworm midguts were differentially expressed. The quantitative real-time PCR (qRT-PCR) results showed that the expression levels of IIS/PI3K-AKT pathway genes including INR , IRS , AKT , PI3K60 and PI3K110 of silkworms in AG were down-regulated compared with that in MG at 0 h. Whereas AKT, PI3K and PI3K60 of silkworms were significantly increased by 1.68-, 1.49-, 1.67-fold, respectively, at 72 h after switched to mulberry leaves than the same instar fed on artificial diet. PDK 's expression of silkworms in AG was higher than that in other two groups at each timepoint. Compared with MG and AG, PTEN and IRS were down-regulated at 48 and 72 h in AG-MG. Collectively, these results indicate that compensatory growth in B. mori is regulated by IIS/PI3K-AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: In insect, host-finding is initiated by selectively laying eggs in particular site, which is known as oviposition. Host preference in lyctines is determined by some features like vessel size, moisture and starch content of the targeted host. Limited information is available on the significance of diet quality other than starch towards oviposition ability and fecundity of the lyctines. This study discusses the effects of nutritional quality of diets on oviposition of Lyctus africanus after feeding with cellulose-, cellulose powder (CP) and alpha cellulose (AC), and wood-based diets. Oviposition test was conducted on quantitative ashless filter papers which served as oviposition sites. The filter papers had been impregnated with nutritive solution and water to attract females laying their eggs. Those oviposition sites were put separately into a plastic jar with 10 pairs of lyctines adult. Then the eggs number and survived adults after two weeks were observed. The results showed that lyctine adults emerged from the cellulose-based diets ovipositing more eggs significantly on nutritive solution- than water-impregnated filter papers. This result may confirm that starch and sugar are the vital nutrients for L. africanus which could attract adult females to lay their eggs. The cellulose-based diets, both CP- and AC-based diet, are likely to affect adult stage of L. africanus to be more fecund by laying more eggs on filter papers. Also, CP-based diet generated the adults with higher survivals after ovipositing the eggs on both nutritive content and water-impregnated filter paper. The diet composition, in the case of cellulose content, is thus suggested to influence the fecundity of the adult insects of L. africanus. [Copyright &y& Elsevier]

Abstract: The growth and reproduction of rice leaffolder, Cnaphalocrocis medinalis, fed on an artificial diet were studied. The results showed that the larvae were able to grow and pupate on the artificial diet. The durations of larvae and pupas of C. medinalis on the artificial diet were 28.1 d and 10.1 d, postponed 4.9 d and 1.7 d respectively, compared with those reared with rice leaves. The number of ovipositions was 41.6 per female, 26.2% higher than that fed on rice leaves. Survival rate curve of larvae was a descent function of mortality-age, with no significant differences from the curve of larvae fed on rice leaves. The net reproductive rate (Ro ), intrinsic rate of increase (rm ) and finite rate of increase (λ) of the population fed on diet were 17.6928, 0.0884 and 1.0924, respectively, and the mean generation time (T) and double time (td ) were prolonged 4.9 d and 1.3 d in comparison with the treatment of rice leaves. Population trend index (I) was 3.26, indicating a growing number of the population of C. medinalis fed on artificial diet. [Copyright &y& Elsevier]

Abstract: Elevated metal burdens in farmed fish can pose potential risks to public health as a result of fish consumption. It has been recognized that dietary exposure is a dominant route for metal accumulation in fish. In this study, we first assessed the metal contamination in commercial fish diet and its raw materials. Squid viscera meal, kelp meal and rapeseed meal had metal-specific contamination and contributed to high metal levels in commercial fish diet. We then quantified the metal assimilation efficiency (AE) in a juvenile marine fish blackhead seabream Acanthopagrus schlegelii using a radiotracer technique to assess the dietary bioavailability of cadmium (Cd), inorganic mercury (Hg(II)), and zinc (Zn). Different sources of protein in artificial diets did not significantly affect the metal AEs, except for Hg(II) from corn meal and Zn from corn meal and rapeseed meal. Generally, metal AEs tended to decrease with increasing dietary metal concentrations. Compared to meso-2,3-dimercaptosuccinic acid (DMSA) and l-cysteine in commercial fish diet, metal additives (i.e., 3000μg Fe/g or 200μg Cu/g) were more influential on metal AEs, probably due to metal competition. The relative bioavailability of metals in natural prey vs. artificial diet was inconsistent and complicated by metal chemical species and gut passage time. Our results indicated that metal contamination in commercial fish diet was probably underestimated in fish aquaculture. [Copyright &y& Elsevier]

Abstract: During two 12week trials, groups of edible sea urchins, Psammechinus miliaris, were fed artificial diets containing carotenoid pigments. The aim was to improve both the biomass and the colour of the sea urchin gonad in terms of its acceptability as a human food-stuff in the European market place. The pigmented artificial diets, based on the formula used by , increased gonad index (GI), pigment deposition and improved gonad colour from that of the initial samples. In Trial I gonad β-carotene levels increased >2 fold, echinenone and total carotenoid >7 fold. Trial II showed greater increases. Diets containing high levels of β-carotene (500mg per kg dry weight of diet) gave rise to the highest percentages of marketable gonad colours (61–73%), and GI of 17.87–19.81%, (Trial I and II respectively). There was some variation in the results for this particular diet treatment across the two trials presumably reflecting individual urchins varying capacity to ingest, deposit or express the carotenoids in their diet. Providing additional lipids in the diets gave no improvement to gonad colour (56% acceptable) or GI (15.95%) suggesting the lipid content of the basic formulation is adequate. Utilizing an esterified form of lutein and zeaxanthin as a pigment source gave no significant improvement in gonad colour (30–63% acceptable) suggesting that this form of xanthophyll cannot be assimilated by P. miliaris. Female urchins had acceptable gonad colouration more often than males. The dominant carotenoid in the successful diets was β-carotene and this was successfully metabolized into echinenone, the dominant carotenoid in all gonad samples. Total levels of echinenone positively correlated with acceptable gonad colour scores. This study demonstrates that 12weeks is sufficient to effect the desired change in gonad biomass and colour in cultivated P. miliaris. [Copyright &y& Elsevier]

Abstract: Stag beetle larvae generally feed on decaying wood; however, it was unknown whether they can use wood-rotting fungi alone as food. Here, to clarify this, newly hatched larvae of Dorcus rectus (Motschulsky) (Coleoptera: Lucanidae) were reared for 14 days on artificial diets containing a fixed amount of freeze-dried mycelia of the following fungi: Bjerkandera adusta, Trametes versicolor, Pleurotus ostreatus, and Fomitopsis pinicola. The mean incremental gain in larval body mass was greatest on diets containing B. adusta, followed by T. versicolor, P. ostreatus, and F. pinicola. The growth rate of body mass correlated positively with mycelial nitrogen content of the different fungi. It also correlated positively with the mycelial content of B. adusta in the diet. Addition of antibiotics to diets with mycelia nearly halved larval growth, indicating that larvae were able to use fungal mycelia as food without the assistance of associated microbes although the microbes positively affected larval growth. Four newly hatched larvae reared on artificial diets containing B. adusta mycelia developed to the second instar in 21–34 days; and one developed to the third (=final) instar. This study provides evidence that fungi may constitute the bulk of the diet of D. rectus larvae. [Copyright &y& Elsevier]

Abstract: A key concern when developing artificial aquaculture diets is their palatability. This study investigated whether the palatability of artificial diets could be improved by incorporating a small quantity of highly preferred natural foods as feeding stimulants. The preference of Tripneustes gratilla for marine plants with which it co-occurs naturally in New South Wales, Australia, was assessed in a laboratory choice feeding experiment. T. gratilla displayed significant preference for the brown alga Ecklonia radiata over five other algae and one seagrass when they were offered simultaneously. Total protein or energy in the plants was not found to account for this preference. However, T. gratilla showed no preference among E. radiata, Sargassum linearifolium and Ulva lactuca when they were dried. Three artificial diets were made by incorporating one of each of these dried seaweeds at 5% dry weight. Although not statistically significant, T. gratilla ate more than twice as much the artificial diet containing S. linearifolium compared to the control diet containing no algae in a choice feeding experiment. In a no-choice feeding experiment, T. gratilla consumed significantly more of the Ecklonia and the Sargassum diets than the control diet despite each of the diets containing approximately the same protein and energy levels. T. gratilla consumed 49 and 43% more protein, and 37 and 44% more energy, respectively, when fed with the Ecklonia and the Sargassum diets compared to the control diet. Juvenile T. gratilla grew significantly faster on a wet weight basis on the Sargassum diet than the control diet at an average increase of 2.4% per day. These results indicate that the small amounts of palatable seaweed added to the artificial diets act as feeding stimulants, increasing the acceptability of artificial sea urchin diets, boosting the protein and energy consumption, and significantly increasing the growth of T. gratilla. Moreover, the fast growth of T. gratilla achieved in this study also indicates that this species would be a good candidate for commercial aquaculture. [Copyright &y& Elsevier]

Abstract: Four closely related species of sea urchins belonging to the genus Echinometra, Echinometra sp. A (Ea), E. mathaei (Em), E. sp. C (Ec), and E. oblonga (Eo), occur sympatrically but in different microhabitats on Okinawan coral reefs. Feeding rates and absorption efficiencies of the four species were investigated in the laboratory by feeding sea urchins ad libitum a diet prepared from turf algae and agar over a 7-day period. Feeding rates differed significantly among the four species of Echinometra (Ea>Em≈Ec>Eo). Absorption efficiencies of protein and lipid did not differ significantly among the four species. Carbohydrate, a major nutrient component in the diet, was absorbed by the four species at significantly different efficiencies (Eo>Ec≈Em>Ea), which resulted in similar interspecific differences in absorption efficiencies of dry matter, total organic matter, and energy. The amount of nutrients absorbed from the diet was directly related to the feeding rate, indicating that the increase in absorption efficiency was not sufficient to completely compensate for low feeding rate. The interspecific difference in physiological performance in relation to feeding and absorption is consistent with taxonomic differentiation among the four species. [Copyright &y& Elsevier]

Abstract: Lab-reared sphingid and noctuid moths appear to feed less than wild moths, and often are starved to enhance responsiveness in feeding assays. To measure the impact of larval nutrition on adult feeding, we raised a model sphingid species, Manduca sexta, on control or modified diets (reduced sugar, protein or water, supplemented β-carotene) or cut tobacco leaves, then conducted feeding assays with artificial flowers. Behaviour was scored and analysed in a double-blind manner. Larval diet affected adult eclosion time, size and fat content, the latter of which was inversely proportional to moth approaches to the floral array in a flight cage. In contrast, behaviours refractory to feeding (sitting, escaping) were associated with sex and barometric pressure, but not with diet or fat content. Frequency of floral approaches and probing was not associated with any variable. However, moths reared on β-carotene-supplemented diet were 2–3 times more likely to feed, and significantly less likely to sit or show “escape” behaviour than were moths from most other treatments. Our results suggest that decreased visual sensitivity, rather than increased fat content, accounts for reduced adult feeding by lab-reared M. sexta. [Copyright &y& Elsevier]

It is becoming increasingly difficult to isolate novel useful microorganisms from the natural environment using conventional screening methods based on pure culture techniques. A novel method for screening microorganisms in symbiotic association with insects was developed. This method involves the following two steps. In the first step, the existence of desired microorganisms that grow well by degrading difficult-to-degrade materials in the gut of insects is detected using the survivability of insects as an indicator. In the second step, the desired microorganisms are selected from the surviving insects. The second step is based on an idea that the guts of insects act as continuous-culture systems whereby microorganisms that cannot degrade diet components are washed out whereas those that can degrade diet components are retained and made to multiply in the gut. Coptotermes formosanus Shiraki was fed with an artificial diet containing phenol as a model of lignin-derived and difficult-to-degrade compound. Each C. formosanus feeding on an artificial diet containing 100 mg/l phenol had different levels of adaptation to the toxicity of phenol. About 20% of C. formosanus fed with an artificial diet containing 100 mg/l phenol died within a few days whereas others survived for more than 10 d. The structure of the intestinal microorganisms of the surviving C. formosanus fed with the 100 mg/l phenol artificial diet gradually changed and was very different from that of the bacterial communities obtained from the enrichment culture of wood-feeding C. formosanus using an artificial medium containing phenol as a sole carbon source. Furthermore, Only three species (as DGGE band) were detected from the gut of wood-feeding C. formosanus, whereas 200 times more phenol-degrading microorganisms were detected in the gut of C. formosanus feeding on a phenol artificial diet. Out of these nine species (as DGGE band) of phenol-degrading microorganisms were isolated. The screening method developed in this study can also be applied to various insects, leading to the isolation of various microorganisms that can degrade difficult-to-degrade compounds. [Copyright &y& Elsevier]

Abstract: Fragments of two artificial diet up-regulated and two prey up-regulated transcripts were isolated from the predatory Pentatomid Perillus bioculatus using suppression subtractive hybridization. A BlastX search found similarities for two diet-upregulated clones, i.e., the tyrosine-3-monooxygenase gene and the gene for the chitin binding protein, Gasp. The probe generated from the tyrosine-3-monooxygenase clone hybridized to two transcripts 2.3 and 1.2kb in size. The two transcripts were differentially regulated: the 2.3kb transcript was upregulated in the first and late third instar diet-fed nymphs, whereas the 1.2kb transcript was upregulated in the second and early third instar diet-fed nymphs. The Gasp gene was upregulated in late third instar nymphs. A positive correlation was found between levels of expression of the isolated genes and the number of generations the insects had been reared on the artificial diet. [Copyright &y& Elsevier]

Abstract: We compared the egg-hatching of Euscepes postfasciatus (Fairmaire) with and without moisture treatment to test whether moisture is necessary during egg incubation when a large number of eggs are gathered into a mass. Moisture treatment exhibited significant undesirable effects on hatching (reduction of hatchability, delay of hatching, and increase of the variance of hatching date) compared to no moisture treatment. In addition, moisture treatment significantly increased the incidence of fungus on the egg surface, which can subsequently contaminate the larval artificial diet. Based on these results, we concluded that moisture is not necessary for incubating E. postfasciatus eggs. Two possible explanations for the undesirable effects of moisture on hatching were discussed: a direct effect by preventing respiration of the eggs and an indirect effect through fungal infection of the eggs. [Copyright &y& Elsevier]

Abstract: Palliative care are intended to children with life limiting conditions. In France, for the majority of pediatric team, the idea of continuity of cares is essential for the announcement of the diagnosis to the final state. The author describes here different situations according to the initial disease of these children. In all cases, the choices of artificial feeding depend of pluridisciplinary medical teams and their experience, and of family opinion. Ethical consideration must be present in this decision. [Copyright &y& Elsevier]

Abstract: We investigated the structural and physiological changes in the radula and digestive system in juvenile blacklip abalone Haliotis rubra, between 80 and 158 days post settlement (PS) to determine if variable growth on artificial diets (and prevalence of runts) are due to an inability to efficiently ingest and digest the diet. Between 80 and 102 days PS, L5 teeth appeared on the radula and there were fewer lateral serrations, consistent with the adult form of the animal, suggesting that this development is in preparation for feeding on macroalgae. Digestive gland complexity (tubule number and density) increased between 80 and 102 days PS and is consistent with greater enzyme production and increased digestive efficiency. Of the enzymes studied, laminarinase and lipase exhibited the highest activities in animals fed a diatom diet, both significantly increasing with age of the abalone. High laminarinase activities reflect higher utilisation of the algal polysaccharide chrysolaminarin in the diatom diet. Ingestion of artificial diet had no adverse effects on the morphological development of the digestive system, but trypsin activity in abalone fed the artificial diet was significantly higher than diatom-fed abalone of similar age, indicative of higher levels of protein in the artificial diet. Similarly, lipase activity was significantly lower in abalone fed the artificial diet and may reflect an inability to digest the fish oil component, which is not found in their natural diet. Future development of artificial diets, especially for juvenile abalone, should focus on the levels and type of lipid provided. Runt abalone (i.e. under-developed compared to their siblings) had radulae similar to much younger 80 days PS abalone and digestive tissue degradation at 137 days PS is evidence that runts have limited ability to ingest food and are nutritionally compromised. [Copyright &y& Elsevier]

Stott''s Abalone Postlarval Production System (SAPPS) was developed to replace livefood as the primary means of settling and growing out abalone seed. Culture plates are initially sprayed with microalgal powder/agar gel solution to induce larval settlement. Abalone seed are then raised on an artificial diet/agar gel solution which is sprayed directly onto the culture plates. This study was conducted to test SAPPS on a commercial scale against the diatom biofilm method and two further trials were conducted to investigate the optimum feeding frequency and agar concentration for SAPPS. A total of 100,000 larval Haliotis diversicolor aquatilis were induced to settle onto 90 mucus conditioned commercial rearing plates (5 racks×18 plates each) in 1500-l tanks to test two treatments; diatom biofilm method and SAPPS. The trial was conducted over a 6-week period and the temperature averaged 24.2±1.0 °C. Settlement was similar on all plates in the two treatments. The settlement rate per plate was 17,820±8460 for the diatom biofilm and 17,280±6390 for SAPPS. The postlarval growth rate on the SAPPS plates was over 50% higher than the growth rate on the diatom plates. The final length of postlarvae was significantly higher (p<0.05) on SAPPS plates (3281±573 μm) than on diatom biofilm plates (2231±314 μm). Furthermore, the survival of postlarvae was also five times higher on SAPPS (51.7%) compared with diatom biofilm (10.6%). SAPPS plates were heavily colonized by marine bacteria which may have acted as a food source for early postlarvae and assisted in the breakdown of polysaccharides. The whole body protein of juveniles was 17.2% in SAPPS compared to 13.3% in diatom biofilm which may suggest that artificial diet was a more balanced and complete nutrient source than diatom biofilm. Smaller scale trials were conducted over 25 days to determine optimum concentration of agar (2.5, 5.0, 7.5 and 10.0 mg/ml) and also to determine specific feed frequency (daily, every second day and every third day). There was no significant difference (p>0.05) in survival rate in both trials. However, the growth rate of postlarvae at 2.5 mg/ml agar was significantly lower than the other treatments and the leaching rate (% weight loss of food) was double that of agar concentrations 5.0–10.0 mg/ml. Growth rate was highest (p<0.05) in the feed frequency experiment for postlarvae fed daily and lowest for those fed every third day. The results suggested that agar concentration was optimal at between 5.0 and 10.0 mg/ml with plates being sprayed daily. SAPPS has potential to be used in industry depending on the development of a mechanized, cost-efficient system for spraying the plates. [Copyright &y& Elsevier]

β-glucuronidase (GUS) is a reporter protein commonly expressed in transgenic plants allowing the visualization of the transformed individuals. In our recent work, we showed that consumption of transformed potato plants expressing this GUS enzyme improves performance of the phloem feeding aphid Myzus persicae. Those results led us to the conclusion that the expression of GUS in potato plants might be responsible for the probiotic effect measured in feeding aphids. In the present paper, artificial diets were used to provide active GUS (10 and 500 μg ml−1), inactivated heated GUS (500 μg ml−1), glucuronic acid (10, 100 and 500 μg ml−1), and bovine serum albumin (500 μg ml−1) to M. persicae. Our results reveal that these chemicals provided as food intake might influence the biological parameters of this aphid. Experiments showed a probiotic effect of 500 μg ml−1 GUS diet, resulting in reduced larval mortality, and increased adult reproduction period and fecundity, which led to an increased population growth potential (rm=0.17±0.01 versus rm=0.12±0.03 for aphids fed on control diet). A lower amount of added GUS led to fewer variations, biological parameters being only slightly altered (rm=0.14±0.03). Statistically similar alterations of the biological parameters were obtained when comparing aphids fed on the diet added with inactivated GUS or the non-structural bovine serum albumin protein (rm=0.15±0.02 and 0.14±0.03, respectively). Feeding assays conducted with glucuronic acid supplemented diets enhanced longevity and nymph production of the adult aphids and reduced larval mortality, resulting in rm=0.15±0.02 for the highest dose (500 μg ml−1). Although 100 μg ml−1 glucuronate diet did not induce any effect on M. persicae (rm=0.12±0.03), aphids fed on 10 μg ml−1 glucuronate diet exhibited unexpected reduced demographic parameters (rm=0.10±0.03). Immuno-histological analysis showed GUS labeling along the whole digestive epithelium of adults and in various tissues including embryos and bacteriocytes. These results suggest that GUS crosses through the digestive tract. Western blots performed with protein extracts of transformed potato plants expressing the gus gene showed a unique band of molecular weight 76 kDa. On the contrary, in extracts from aphids fed on transgenic potato plants or bred on GUS 500 μg ml−1 artificial diet, several proteins of lower molecular weight were hybridized, revealing proteolysis of ingested GUS. It is concluded that GUS protein, and more precisely GUS activity, is responsible for the probiotic effects on aphid feeding. The possible pathways of induction of such physiological alterations by GUS are discussed. [Copyright &y& Elsevier]

Many studies have paid particular attention to the role of either secondary plant compounds or amino acids as determinants of host-plant range in phytophagous insects. Here we examine the relative importance of both of these classes of compound in host acceptance by generalist and specialist morphs of the black bean aphid, Aphis fabae, that are morphologically similar and genetically identical. Eleven secondary plant compounds and six amino acids with known biological activity in aphids are presented to insects within an artificial membrane system as single compounds, mixtures of same-class compounds and combined mixtures of the two classes of compound. It is found that 1) when specific single secondary compounds and amino acids are presented to generalist and specialist morphs of A. fabae, differential responses are exclusively consistent with plant-use strategy for amino acids but not for secondary compounds, 2) neither secondary compound nor amino acid mixtures give reproductive responses entirely consistent with plant range, but the response to secondary compounds is broadly consistent with plant range whereas the response to amino acids is not, 3) when secondary compounds and amino acid mixtures are combined, the response to secondary compounds generally dominates that to amino acids. Some scenarios of plant-range determination by secondary plant compounds and amino acids, suggested by results, are discussed. [Copyright &y& Elsevier]

Most studies linking dietary variation with insect fitness focus on a single dietary component and late larval growth. We examined the effects of variation in multiple dietary factors over most life stages of the sphingid moth, Manduca sexta. Larvae received artificial diets in which protein, sucrose, and water content were varied. The relationship between larval size, growth and consumption rates differed significantly across diets. Larvae on control and low-sucrose diets grew most rapidly and attained the largest pupal and adult sizes. Conversely, larvae on low-water and low-protein diets initially grew slowly, but accelerated in the fifth instar and became pupae and adults comparable to control animals in size. There were no fundamental differences in protein:carbohydrate consumption patterns or strategies among experimental diets and larval instars. However, inadequate dietary water appeared to be more important for early than late instar larvae. Larvae on all artificial diets showed increasing fat content throughout all stages, including wandering and metamorphosis. Compensatory feeding among low-water and low-protein larvae was correlated with significantly higher fat content in larvae, pupae and adults, whereas low-sucrose animals were substantially leaner than those on the control diet. These differences may have strong effects on adult physiology, reproduction, and foraging patterns. [Copyright &y& Elsevier]

Green sea urchins (Strongylocentrotus droebachiensis), taken from the wild were fed on a grain-based artificial diet over a 9-week period. At intervals, the animals were harvested and the gonads analysed for proximate composition, lipid class distribution, fatty acid and carotenoid pigment compositions. During the feeding period the lipid content decreased and the moisture content increased. Meanwhile, the protein content was highest after 9 weeks of feeding on the artificial diet. Major non-polar lipid classes were triacylglycerol (TAG), free fatty acids (FFA) and sterols (ST) while dominant polar lipid classes were phosphatidylcholine (PC) and phosphatidylethanolamine (PE). The content of PC was much higher than that of PE on week 0. However, PE became dominant on week 9 after feeding on the artificial diet. The fatty acids 14:0 and 16:0 were the major saturated fatty acids (SFA), consistently present in the total, non-polar and polar lipids of sea urchin gonads. Polyunsaturated fatty acid (PUFA) 20:5n-3 (eicosapentaenoic acid, EPA) was the highest on week 0 while 18:2 n-6 became dominant with increased feeding period with a concurrent decrease in the content of 20:5n-3. Further, 20:1n-15 was the major monounsaturated fatty acid (MUFA) at week 0, but its content decreased significantly (P<0.05) after introducing the artificial diet. The total carotenoid content decreased by 50% at the end of the feeding period. Major carotenoids present in sea urchin gonads were echininone and β-carotene. The relative content of echininone was lowest at week 0, but increased when the urchins were fed on the artificial diet with a simultaneous reduction in β-carotene levels. The study demonstrates the importance of feed supply in lipid composition of sea urchin gonads. [Copyright &y& Elsevier]

Vitellogenic oocytes from Perillus bioculatus have two native vitellins, Vt1 and Vt2, with molecular masses of 553 and 228 kDa, respectively. The hemolymph contains a major vitellogenin, Vg, with a molecular mass of 528 kDa that consists of three apoproteins with masses of 177, 84 and 59 kDa, respectively. Antibodies to purified Vt2 reacted with ovary extracts, egg extracts and female hemolymph, but not with male hemolymph in immunodiffusion tests. Western blots showed that anti Vt2 reacted with both Vt1, Vt2 and with Vg. Vitellogenesis starts at an ovarian score of 12 at 2.4 days after emergence. The first cycle of egg development is completed in ovaries with a score of 112 at 7.7 days. During this 5.3 day period, the ovaries of a single female incorporated 1833 μg of protein to form vitellin. Vitellogenin levels start to increase in females 2.5 days after emergence and reached 17.8 μg/μl by 5.5 days. After 5.5 days vitellogenin levels fluctuated between 9.7 and 19.9 μg/μl. Most diapausing females contained no ovarian follicles in the vitellarium and their hemolymph contained less than 1 μg/μl of vitellogenin. Treating diapausing females with 1 μg of JH III increased vitellogenin levels over 120-fold. Insects maintained on a liver-based artificial diet had lower vitellogenin levels than the controls at all sample times and did not show an increase in vitellogenin concentration until 11.5 days. Treating insects on the artificial diet with 10 μg of JH III elevated vitellogenin levels to about a fourth of that found in prey-fed insects of a comparable age. This suggests that females fed the artificial diet have low levels of essential materials needed for vitellogenin production. [ABSTRACT FROM AUTHOR]

In our efforts to understand the biology of soldier-producing aphids, we attempted to maintain them in the laboratory using a chemically defined artificial diet. The ability of 16 species from the subfamilies Eriosomatinae and Hormaphidinae, most of which are soldier-producing species, to survive on the artificial diet was examined. Some species neither fed nor grew on the diet, whereas other species accepted the diet, grew to some extent, and managed to produce a small number of short-lived offspring. Although they performed poorly on the diet in general, aphid performance was correlated with the stage in the life cycle and the developmental stadium in that aphids of the gall generation tended to accept the diet and survive on it, whereas aphids of the non-gall generation did not. Also, old insects tended to perform better on the diet than young nymphs. Notably, only one species, Tuberaphis styraci, a gall-forming aphid that produces 2nd instar sterile soldier, showed good performance on the diet. Insects collected from galls (generation G0) survived on the diet, grew well, and produced many progeny. Three successive generations (G1, G2 and G3) were produced on the diet. Developmental period, adult body size, and age of first reproduction were almost constant through G0, G1 and G2 whereas fecundity, adult longevity and daily offspring production declined as the generations proceeded. These results are comparable to previous studies in which pest aphids have been maintained on similar artificial diets for several generations. Therefore, it is suggested that the artificial-diet rearing system will provide a useful tool to investigate various biological aspects of the soldier-producing eusocial aphid, T. styraci. [ABSTRACT FROM AUTHOR]

• Generally, mosquito production requires blood feeding to obtain proteins for egg development. • Sugar assisted protein (SAP) diets provide a novel and simple way to feed mosquitoes. • No attractant, phagostimulant, heat and membrane feeder require for SAP diet feeding. • The SAP diets effectively engorge mosquitoes and produce similar fecundity to live animal blood feeding. • Multiple cyclic generations (10) were maintained on SAP diets. Most artificial dietary systems for feeding mosquitoes require a membrane feeder, host cues, phosphate saline buffers and a phagostimulant. These multicomponent feeders are complex, expansive and cumbersome that requires fully trained personnel. The objective of the present is to develop a simple sugar assisted protein (SAP) diet for the egg production of Aedes albopictus. The present study assessed the potential use of SAP dietary system on the engorgement, fecundity, preference of diet components and production of multiple generations of Ae. albopictus. Our data show that the female mosquitoes have strongly preferred a diet with: (i) a combination of sugar and protein over the individual component, and (ii) water over PBS (phosphate buffered saline) buffer as a carrier, whereas adenosine triphosphate (ATP) was not required as a phagostimulant. Based on our optimization data, the SAP diets (10–20% bovine serum albumin in 5% sucrose aqueous solution) do not require chemo-attractive lure, phagostimulant ATP, temperature and membrane feeding components. Female mosquitoes readily engorge on SAP diets and show similar rates of survival and fecundity compared to those when blood-fed on live animals. In addition, the number of eggs produced by female mosquitoes fed on SAP diets kept consistent for 10 consecutive generations. Our results indicate that SAP diet is a potential alternative against blood feeding that is simple and cost-effective diets for Ae. albopictus colony maintenance and to support large scale mass- production for experimental and other purposes. [ABSTRACT FROM AUTHOR]

Chill-susceptible insects enter the reversible state of chill coma at their critical thermal minimum (CT min). During chill coma, movement of Na+ and water from the hemolymph to the gut lumen disrupt ion and water balance. Recovery from cold exposure requires re-establishment of this balance, and failure to do so results in chilling injury or death. We hypothesized that the passive leak of Na+ and consequently water during cold exposure is driven by the [Na+] differential between the gut and hemolymph. To determine the extent to which this [Na+] differential affects cold tolerance, we used artificial diets to load the guts of fall field crickets (Gryllus pennsylvanicus) with various concentrations of Na+. Manipulating [Na+] differentials had no effect on the CT min , agreeing with recent studies demonstrating that chill coma onset precedes loss of ion balance in the cold. A high [Na+] diet reversed the direction of the [Na+] differential between the gut and hemolymph. Crickets fed a high [Na+] diet recovered from 12 h of chill coma nearly twice as fast as those fed low [Na+] diets. However, the high [Na+] diet was detrimental to survival after prolonged cold exposure (three days at 0 °C). Therefore, while a reduced [Na+] differential helps crickets recover from short-term cold exposure, an increased gut Na+ load itself appears to carry longer-term costs and promotes irreversible chilling injury. Unlabelled Image • Feeding crickets high [Na+] diets speeds recovery from short-term cold exposure. • High gut [Na+] does not affect movement of water into the hindgut. • Dietary Na+ stress drives higher mortality after long-term cold exposure. [ABSTRACT FROM AUTHOR]