Choice Feeding Research Articles

Feeding Preferences by Reticulitermes tibialis (Blattodea: Isoptera: Rhinotermitidae) between Four Tallgrass Prairie Grasses

Termite researchers on The Nature Conservancy's Joseph H. Williams Tallgrass Prairie Preserve in northeast Oklahoma have long been interested about nutritional resources used by subterranean termites inhabiting the Preserve. In 12-week choice and no-choice laboratory feeding tests, subterranean termites were fed a mixture of stems-and-leaves, or roots only, of four predominant grasses growing on the Preserve: Indiangrass – Sorghastrum nutans L; Switchgrass – Panicum vigatum L; Big Bluestem – Andropogan gerardii Vitman; and Little Bluestem – Schizachyrium scoparium (Michx.). Termites consumed all of these food choices but preferred roots compared with stems and leaves. In choice feeding tests, termites preferred Switchgrass roots. In no-choice feeding tests, roots of Indiangrass and Big Bluestem were consumed in greatest amounts. All four grasses were palatable to Reticulitermes tibialis, a subterranean termite common throughout the Preserve.

Impacts of Bioassay Type on Insecticide Resistance Assessment in the German Cockroach (Blattodea: Ectobiidae).

The German cockroach, Blattella germanica (L.), is one of the most critical urban pests globally due to the health risks it imposes on people, such as asthma. Insecticides are known to manage large cockroach population sizes, but the rapid rate at which they develop resistance is a continuing problem. Dealing with insecticide resistance can be expensive and time-consuming for both the consumer and the pest management professional (PMP) applying the treatment. Each cockroach population is unique because different strains have different insecticide susceptibilities, so resistance profiles must be considered. This study addressed the above issue in a controlled laboratory setting. Cockroach strains from Indianapolis, Indiana, Danville, Illinois, and Baltimore, Maryland, USA were used. Four insecticide active ingredients (AIs) most used by consumers and PMPs were selected for testing in vial bioassays to establish resistance profiles. Next, no-choice and choice feeding assays with four currently registered bait products were performed to assess the impacts of competing food and circadian rhythms on bait resistance levels. The results indicate that emamectin benzoate (Optigard) was the most effective AI in causing the highest mortality in all strains in vial and no-choice bioassays; whereas, the other AIs and products were more impacted by resistance. The results acquired from these studies can help develop rapid tests for use by PMPs based on the no-choice feeding assay while also adding more information supporting current resistance and cross-resistance evolution theories.

Perilaku pemilihan pakan plastik dan respons biologi imago kumbang Tenebrio molitor L. (Coleoptera: Tenebrionidae)

Kumbang Tenebrio molitor L. berpotensi sebagai pengurai plastik. Plastik juga dapat terdegradasi oleh paparan sinar matahari. Penelitian ini bertujuan untuk memelajari perilaku pemilihan pakan dan respon biologis kumbang T. molitor yang dipaparkan pada berbagai jenis plastik. Tujuh jenis plastik, yaitu bioplastik (Bio), expanded styrofoam (EPS), oxo-biodegradable (Oxo), dan ketiga plastik Bio-P, EPS-P dan Oxo-P yang telah dipaparkan pada sinar matahari, serta kontrol berupa campuran pollard dan irisan wortel diujikan pada imago kumbang T. molitor berumur empat hari. Uji pemilihan pakan metode choice feeding dilakukan pada siang dan malam hari dengan melepas 200 dan 300 individu kumbang di tengah cawan petri berdiameter ±15 cm, bersekat 7 ruangan menjari, yang kemudian diamati pergerakannya hingga 24 jam. Uji respons biologi melalui metode force feeding dilakukan dengan melepas 10 kumbang jantan dan betina dalam sebuah cawan petri berisi jenis pakan uji diuraikan di atas. Hasil penelitian menunjukkan bahwa pakan pollard paling banyak dikunjungi oleh sekitar 32–39% populasi kumbang. Pada perlakuan pakan tanpa pollard, 20% kumbang memilih plastik EPS, EPS-P, dan Bio. Kumbang bertahan hidup 23 dan 40 hari, masing-masing pada pakan Bio dan Bio-P. Produksi telur oleh kumbang yang diberi pakan Bio dan Bio-P adalah 2 dan 3 butir/betina/10 hari. Sekitar 85% pakan pollard yang dikonsumsi kumbang berkontribusi terhadap penambahan 5% berat tubuhnya. Sekitar 58–64% pakan Bio, Bio-P, EPS, EPS-P dan 6–12% Oxo, Oxo-P berhasil dikonsumsi kumbang. Penurunan berat tubuh terjadi pada seluruh kumbang yang diberi perlakuan pakan plastik, berkisar antara 13–28%.

The relationship between the infestation of Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) and the chlorophyll content in different Eggplant varieties

The sweet potato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is one of the most important pests in vegetables. Although the host plant Solanum melongena, is considered the most preferred, the whiteflies have preferences for particular varieties of eggplant. In this study, we evaluated three eggplant varieties in choice feeding tests. We found that the varieties of Zomorrod and Barcelona were the most preferred with the highest numbers of whitefly nymphs, which were 312 and 300 per leaf, respectively, on the last week of May. In comparison, the nymph average was 171.8 per leaf on the last week of May on the kareema. Chlorophyll concentration has been negatively affected by the infestation of B. tabaci. The investigation of the chlorophyll content ratio between the uninfested and infested eggplant leaves showed a decrease in chlorophyll content at 13.95 and 6.60 11 mg/L of the Zumorrod variety for the uninfested and infested leaves, respectively, with 52.67% chlorophyll reduction. At the same time, the mean chlorophyll content for uninfested and infested eggplant leaves of the Barcelona variety was 12.74 and 4.95 mg/L, respectively, with 61.14% chlorophyll reduction. At the same time, the Kareema variety was recorded at 17.49 and 4.95 mg/L for the uninfested and infested leaves, respectively, with 72.39% chlorophyll reduction. Furthermore, feeding by B. tabaci reduced leaf photosynthesis in eggplant by restricting gas exchange through stomata and reducing chlorophyll's content and photosynthetic capacity. Keywords: population density; piercing pest; Bemisia tabaci; Solanum melongena; host preference; plant pigments

Influence of ground beetles (Carabidae) as biological agent to control of the Mediterranean fruit fly pupae, Ceratitis capitata, in Iranian citrus orchards

• High diversity and density of Carabidae observed with eliminated pesticide spray. • Instead pesticide, mineral oil spray led conserving the carabids species. • Seasonal density fluctuation of Carabidae was observed, increasing in spring. • Highest population of Carabidae with the peak of fruit fly damage in September. • H. rufipes, B. karelinii and Pterostichus macer were the most voracious predators. Damage by Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in the northern Iranian citrus orchards has been led to spray by different chemical pesticides. The present study was conducted in the citrus orchard in Mazandaran province of Iran where with the exception of mineral oil treatments for scale insects, had not been sprayed with synthetic insecticides for six years. The purpose of this study was initially to investigate faun and seasonal activity of predaceous ground carabid beetles in the citrus orchards. Additionally, their role as predators of Ceratitis capitata (Wiedemann) pupae was evaluated under laboratory and field conditions. Predation in laboratory was evaluated by no choice feeding experiments while predation under field conditions was evaluated by molecular detection of the pest DNA in the gut contents of field-collected Carabids. A total of 3,437 beetles of ten carabid species were collected from a non-chemical treatment citrus orchard. The results of the seasonal density fluctuation indicated increasing population in spring reaching the highest in September, simultaneously with the peak of fruit fly damage, and thereafter decreasing during winter when the pest was overwintering. However, three species, Harpalus rufipes, Broscus karelinii and Brachinus brevicollis were most abundant in the field collection but the results of no-choice experiments in the laboratory indicated H. rufipes, B. karelinii and Pterostichus macer were the most voracious predators on pupae. Results of gut content analysis of the voracious species indicated the positive testing for pest DNA in 79.16 % of H. rufipes , 76.92% of B. karelinii and 75% of P. macer of analyzed beetles. The results of the study strongly indicated that in citrus orchards where intensive spraying is eliminated, natural enemies such as Carabid beetles could play an important role in reducing pests such as medfly.

Evidence for Cardiac Glycosides in Foliage of Colorado Potato Beetle-Resistant Solanum okadae.

Leptinotarsa decemlineata, the Colorado potato beetle (CPB), is a herbivore that primarily feeds on Solanum foliage and is a global pest of the potato agricultural industry. Potato breeding through cross-hybridization with CPB-resistant wild relatives is used for genetic improvement. The wild species Solanum okadae was demonstrated to deter CPB feeding in choice and no choice feeding assays. Liquid chromatography-mass spectrometry (LC-MS) was used for comparative metabolite profiling between S. okadae and CPB-susceptible domesticated potato variety, Solanum tuberosum cv. Shepody. Major foliar metabolites detected were steroidal glycoalkaloids (SGAs) with tomatine and dehydrotomatine produced in S. okadae and solanine and chaconine in S. tuberosum cv. Shepody. Cardiac glycosides were also detected in the foliar metabolite profile of S. okadae but not S. tuberosum cv. Shepody. This class of plant compounds have known insecticidal activity through inhibition of animal Na+/K+ ATPase. Thin-layer chromatography (TLC) separation of foliar extracts also provided evidence for cardiac glycosides in S. okadae. Cardiac glycosides are known inhibitors of Na+/K+ ATPase, and foliar extracts from S. okadae (OKA15), but not S. tuberosum cv. Shepody, were able to inhibit the Na+/K+ ATPase of CPB. These findings suggest a novel mechanism of plant resistance against CPB involving production of cardiac glycosides in S. okadae.

Eat, Drink, Live: Foraging behavior of a nectarivore when relative humidity varies but nectar resources do not

To meet energetic and osmotic demands, animals make dynamic foraging decisions about food quality and quantity. In the wild, foraging animals may be forced to consume a less preferred or sub-optimal food source for long periods of time. Few choice feeding assays in laboratory settings approximate such contingencies. In this study the foraging behaviors of the hawkmoth Manduca sexta were measured when adult moths were placed within different relative humidity (RH) environments (20%, 40%, 60% and 80% RH) and provided with only one of the following experimental nectars: 0% (water), 12% or 24 % w/V sucrose solutions. Overall, ambient humidity influenced survivorship and foraging behaviors. Moth survivorship increased at higher ambient humidity regardless of experimental nectar. Moths that had access to experimental nectar imbibed large volumes of fluid regardless of what nectar was offered when placed at the lowest humidity (20% RH). However, when placed at the highest humidity (80% RH), moths imbibed higher volumes of fluid when given access to experimental nectar with sucrose in comparison with water. RH also influenced daily foraging behaviors: peak nectar consumption occurred earlier at lower RH levels. Consistent with previous studies in which moths could choose among nectar solutions, total energy intake was not affected by ambient RH under no-choice conditions. However, the proportion of time spent foraging and total energy consumption were significantly reduced across all RH levels in no-choice assays, when compared with previous studies of choice assays under the same conditions. Our results show that even when M. sexta moths are presented with limited options, they can alter their foraging behavior in response to environmental changes, enabling them to meet osmotic and/or energetic demands.

Grazing preference and isotopic contributions of kelp to Zostera marina mesograzers

In seagrass food webs, small invertebrate mesograzers often exert top-down control on algal epiphytes growing on seagrass blades, which in turn releases the seagrass from competition for light and nutrients. Yet, nearshore habitat boundaries are permeable, and allochthonous subsidies can provide alternative food sources to in-situ production in seagrass meadows, which may in turn alter mesograzer-epiphyte interactions. We examined the contribution of allochthonous kelp (Nereocystis luetkeana), autochthonous epiphytic macroalgal (Smithora naiadum), Ulva lactuca, and seagrass production to mesograzer diets in a subtidal Zostera marina (eelgrass) meadow. In both choice feeding experiments and isotopic analysis, mesograzer diets revealed a preference for allochthonous N. luetkeana over Z. marina, S. naiadum, and U. lactuca. Notably, Idotea resecata showed an ~20x greater consumption rate for N. luetkeana in feeding experiments over other macrophytes. In the meadow, we found a positive relationship between epiphytic S. naiadum and gammarid amphipod biomass suggesting weak top-down control on the S. naiadum biomass. Epiphyte biomass may be driven by bottom-up factors such as environmental conditions, or the availability and preference of allochthonous kelp, though further work is needed to disentangle these interactions. Additionally, we found that gammarid and caprellid amphipod biomass were positively influenced by adjacency to kelp at seagrass meadow edges. Our findings suggest that N. luetkeana kelp subsidies are important to the diets of mesograzers in Z. marina meadows. Spatial planning and management of marine areas should consider trophic linkages between kelp and eelgrass habitats as a critical seascape feature if the goal is to conserve nearshore food web structure and function.

Effect of Whole Wheat (Triticum aestivum) Feeding on the Performance of Commercial Broilers

An experiment was conducted for six weeks to study the effect of mixed or choice feeding of whole wheat on the performance of commercial broiler chicken. A total of 352 straight-run day-old commercial broiler chickens were randomly divided into 11 treatments from T1 to T11, with 32 chicks in each treatment and eight chicks in each of four replicates. The corn soya control diet (T1) was fed to the broiler birds without the inclusion of wheat. Results indicated that final body weight, weight gain, and FCR were significantly (p < 0.05) improved in broiler birds fed with 40% choice feeding of wheat at marketing age without affecting feed consumption. The wheat consumption was linearly increased in the wheat choice feeding levels from 20 to 100 %. The study concluded that the choice feeding of wheat instead of maize at 40% was cost-effective and beneficial for improving growth performance.

Polyphagous insect Olepa sps. feeding on cardenolide rich Calotropis gigantea (L.) leaves and detoxification mechanism involving GST

Cardenolides, a group of cardiac glycosides are potent inhibitors of Na+/K+ ATPase pump in mammals, animals including insects. Some insects can circumvent the toxicity of cardenolides by mechanisms like target site resistance and metabolic resistance resulting in enhanced tolerance or adaptation. In this paper, we report an intriguing observation of a polyphagous feeder feeding gregariously on the leaves of Calotropis gigantea (L.) without any apparent adverse effect. No choice feeding assay showed higher larval biomass and reduced number of days to develop on C. gigantea leaves compared to Ricinus and banana. We found the activity of GST higher in C. gigantea fed larva and HR LC-MS analysis of Olepa sps. revealed the presence of glutathione-strophanthidin conjugate in larval body tissue. In silico molecular simulation results confirmed strong interaction between delta variant GST and glutathione-strophanthidin complex. The sequestration site and cost benefit of glutathione-strophanthidin sequestration in body tissues of Olepa sps. needs further investigation.

Efficacy of Eight Anticoagulant Food Baits in House Mouse (Mus musculus): Comparison of Choice and No-Choice Laboratory Testing Approaches

House mouse (Mus musculus) is a cosmopolitan pest in agricultural facilities, commodity stores and rural and urban environments. It is regularly controlled by anticoagulant-based baits. Since the number of registered active ingredients is limited, the producers are trying to develop new formulations with increased tamper-resistance, attractiveness and palatability. Reliable and economical methods for laboratory screening/testing are needed. Therefore, this work compared simple no-choice with more economically demanding choice feeding tests for laboratory evaluation of efficacy of rodenticide anticoagulant-based preparations in wild populations of house mouse. We analyzed mice survival and bait intake of the various rodenticide commercial preparations differing in a toxic active substance (warfarin, bromadiolone, brodifacoum, difethialone) and nontoxic food lure components. In most cases, we found insignificant differences in survival of house mice treated with eight test baits within the no-choice and choice feeding tests. We rejected the tested hypothesis that there would be significant differences in all tested preparations for two different testing approaches.

Predators minimize energy costs, rather than maximize energy gains under warming: Evidence from a microcosm feeding experiment

Abstract Climate warming may alter predator–prey interactions and predator feeding behaviour due to increased metabolic demands. How predators meet these increased demands may depend on trade‐offs in prey energy content and body size, handling time and other functional constraints. We tested hypotheses associated with these trade‐offs with the predatory mite Stratiolaelaps scimitus, and three prey that differed in body size, energy content, and defenses (Folsomia candida, Oppia nitens, and Carpoglyphus lactis). We estimated metabolic rate, predation in choice and no choice feeding trials, movement rate, and lipid and protein content for all four species at 16°C and 24°C. We used these data to estimate the predator's energy demands and compared these to estimated energy intake in the choice feeding trials. Predators had greater metabolic demands at 24°C than at 16°C, but temperature did not affect predator or prey movement rates. Warming decreased lipid content, but not protein content, of all three prey species, leading to lower energy content for C. lactis and O. nitens, but not F. candida. In both feeding trials at 24°C, predators increased their feeding on the smaller, energy‐poor C. lactis, but not the larger, energy‐rich F. candida, resulting in lower estimated energy intake. S. scimitus did not feed on O. nitens at either temperature. Predators increasingly fed on small‐bodied prey under warming and not the large‐bodied prey despite the potential for greater energetic gains from larger prey. We posit that predators minimized energy lost during feeding through lower handling costs associated with C. lactis, rather than maximize energy gain. We conclude that selection of prey based on body size changes with temperature as a trade‐off for predators to balance increased metabolic demands. As predators provide top‐down control and regulate energy flow through the consumption of their prey, changes to predator feeding behaviour with climate warming may affect food web dynamics and ecosystem‐level processes. Read the free Plain Language Summary for this article on the Journal blog.

Effect of cannibalism phenomenon on some biological aspects and predation efficiency on Tetranychus urticae Koch of the ladybird beetle, Coccinella undecimpunctata Linnaeus

The coccinellid predator, Coccinella undecimpunctata (L.) is one of the most important insect predator, which plays an important role in regulation of too many insect pests in Egypt and worldwide. Cannibalism phenomenon is a well-known behavioral feature in this predator, as the larvae and adults prey upon each other. The consumption capacity of this predator on Tetranychus urticae Koch, as well the eggs, first and second larval instars of the this coccinellid was evaluated. The adults and 4th larval instar and adults of C. undecimpunctata devoured more prey compared to those devoured by 1st, 2 and 3rd larval instars. The fourth larval instar of the coccinellid fed upon an average of 96.7 ± 1.2 eggs and 12.0 ± 0.7 larvae of first larvae instar of the same species in Petri dish, in the absence of the spider mite (non – choice feeding). In the presence of the mite and eggs of C. undecimpunctata, the fourth larval instar fed upon 2.2 ± 0.8 eggs and consumed only 1.0 ± 0.5 larvae in 1st larval instar of C. undecimpunctata (choice feeding), and consumed and consumed 126.0 ± 1.0 individual of spider mite in the absence of other prey (non- choice feeding). The adult of the coccinellid fed upon 10.52 ± 0.9 eggs and 5.09 ± 0.5 1st larval instars, in the absence of the mite, but fed upon 1.08 ± 0.15 eggs in the presence of the spider mite and C. undecimpunctata eggs in the same dich. Also, the coccinellid adult fed upon 0.19 ± 0.21 first larval instars in the presence of C. undecimpunctata larval and mites found in the same Petri dish. The adults of C. undecimpunctata consumed 45.83 ± 1.17 individual of the spider mite in the absence of eggs and larvae of C. undecimpunctata. Data of cannibalism and predatory efficiency show that eggs and 1st larval instars of C. undecimpunctata are more devoured by C. undecimpunctata adults comparing to 4th larval inster and larvae of the coccinellid. The two-spotted spider mite is the preferred to all stage of the coccinellid. Results show that scarcity of the prey is one the main reason to cannibalism phenomenon, but it is a conspecific behavior of all coccinellids to keep all species.

Daya Suka Kalkun terhadap Hijauan, Dedak Padi dan Ransum Komersial dengan Free Choice Feeding

The purpose of this study was to evaluate the consumption of feed ingredients (forage, rice bran and commercial rations) in adult local turkeys using free choice feeding. A total of seven adult male turkeys were used in this study, fed with forage (Musa paradisiaca, Ipomea spp, and Indigofera sp leaves), rice brand and commercial ration. Five kinds of feed ingredients were placed in different feeders in each turkey cage. The fresh cut forage was prepared into small pieces of 1-2 cm. Each feed ingredient was analyzed for nutrient content (moisture content, crude protein, crude fat, crude fiber, NFE (Nitrogen Free Extract), ash and gross energy). The data obtained were analyzed descriptively. The results showed that the most palatability forage by adult native turkeys was ipomea spp, indigofera spp and Musa paradisiaca leaves respectively. The commercial ration was the most preferred feed ingredient of all the feed ingredients tested and was followed by rice bran. Adult local turkeys consumed fresh forage was 62 % and total rice bran and commercial feeds was 38%, resp. Consumption of dry matter forage was 17.59% and total rice bran and commercial rations was 82.41%. It can be concluded that turkey feed can consist of forage, rice bran and commercial ration.
 Key words: free choice feeding, Indigofera sp, Ipomea sp, Musa paradisiaca, native turkey, rice bran

Biological resistance of sandwich particleboard made with sugarcane, thermally-treated Pinus wood and malva fiber

Particleboards produced with other lignocellulosic materials, beyond wood, are promising products for the furniture and building construction components, as doors, lining, floor, partitions, and coverings. However, there is little information about the resistance of them to xylophagous organisms. This is important due the different uses of particleboards, where they will be subject to attacks by decaying organisms, which can affect a structure and put people at risk. The present study aims to determine the biological resistance of particleboard produced with pine, sugarcane bagasse and malva particles to xylophagous organisms. The particleboard was produced with different proportions of pine wood heat treated at 200 °C and malva fiber (outer layers) and sugarcane bagasse core glued with an adhesive based on polyurethane from castor oil. No-choice and choice feeding tests with dry wood (Cryptotermes brevis) and conehead (Nasutitermes corniger) termites were carried out for the resistance test to xylophagous organisms, in addition to a test with rotting fungi which cause brown (Gloeophyllum trabeum and Rhodonia placenta) and white rot (Irpex lacteus and Trametes versicolor). The trial with dry wood termites showed low mass losses, regardless of the proportions applied. The mass losses were accentuated for the test with conehead termite, having the particleboard composed of 100% pine been the most resistant among the boards tested. The greatest mass losses for fungal resistance were caused by Gloeophyllum trabeum. The particleboard produced with 100% pine (outer layer) showed the highest resistance to the tested xylophagous organisms.

Requirements of Energy and Protein for Arabic Chicken Hens During Late Egg Production Period

The present study aimed to estimate the metabolizable energy (ME) and protein (CP) requirements of Arabic chicken hens during the late egg production period reared under a semi-scavenging system with free-choice feeding. A total of 112 sixty-two-week-old Arabic chicken hens were used. The treatments were control and the choice diet consisted of 6 replicate pens. Control hens received a control diet (2750 kcal of ME/kg and 14.1% of CP) complying with the Hy-line Brown Commercial Management Guide 2011, whereas the choice hens offered control and three other diets (high energy-high protein [3006 and 17.3], high energy-low protein [3089 and 12.7], and low energy-high protein [2656 and 17.0] kcal of ME/kg and % of CP, respectively). Feed, ME, and CP intake, the concentration of dietary ME and CP, and egg production were recorded weekly. Data were analyzed using Proc Mixed of SAS. The feeding method influenced feed intake, CP concentration, and ME concentration but had no significant effect on CP intake, ME intake, and egg production. Weekly feed intake of choice hens was lower than that of control hens (514.03 vs. 551.18 g /hen/week; P<0.03). Dietary concentrations of ME and CP in the choice hens were higher than those in the control hens (2957 vs. 2750 kcal of ME/kg; P<0.001 and 150.6 vs. 14.1 g of CP/kg; P<0.001). Egg production of the choice hens was not significantly higher than that of the control hens (51.17% vs. 46.82%; P>0.05). Feed intake, CP intake, and ME intake decreased significantly at week 66 onward, while egg production decreased at week 65 onward. It can be concluded that Arabic chicken hens in the late egg production period were able to adjust their energy and protein requirements by consuming more from high dietary energy than from a high dietary protein. Based on the choice feeding, ME and CP requirements for Arabic chicken hens during the late egg production period in the semi-scavenging system were 2957 kcal/kg and 151 g/kg and higher than ME and CP contain in the control diet of 2750 kcal/kg and 141 g/kg to maintain egg production. The egg mass and feed conversion ratio were better in the choice hens group.

Potential of the mirid bug, Engytatus nicotianae, for the biological control of the tomato-potato psyllid in greenhouses

The tomato-potato psyllid (TPP), Bactericera cockerelli, is a serious pest of solanaceous crops. As an alternative to the use of insecticides, we tested the potential of the mirid bug Engytatus nicotianae (adults) as a biocontrol agent of TPP on greenhouse tomato plants. The experiment comprised: a) a laboratory choice feeding assay to investigate the preferences of E. nicotianae when offered TPP eggs and nymphs and b) a greenhouse experiment to assess the potential of E. nicotianae as a biocontrol agent under close to commercial conditions. The laboratory choice experiment highlighted a preference by E. nicotianae for the first two TPP instars, followed by the third instar and then the eggs. Consumption of fourth instars occurred only when all other life-stages had been consumed. In the cage experiment, the E. nicotianae-only treatment produced the same numbers of fruits and flowers as the control (no insects), even though TPP feeds on tomato leaves and stems. In contrast, the TPP-only treatment resulted in fewer fruits and flowers. The simultaneous introduction of E. nicotianae and TPP markedly reduced TPP build up compared to the TPP-only treatment and prevented the pest from establishing at all in four of the seven replicates of the experiment. These findings suggest that E. nicotianae should be considered as a potential biocontrol tool against TPP and further research is needed to determine an optimum release configuration.

Growth, physiological, and molecular responses of broiler quail to dietary source, particle size, and choice feeding of calcium

Two experiments were performed to explore the effect of dietary supplemental different sources and particle sizes of calcium (Ca) on growth performance, bone mineralisation, blood attributes, and calbindin gene expression in broiler quail. In experiment 1, 480-day old broiler Japanese quail (Coturnix japonica) were allotted to four dietary treatments based on a factorial arrangement (2 × 2) consisting of basal diets formulated either with limestone or oyster shell with coarse or fine particles. Supplemental coarse oyster shell impaired growth performance and Ca intake compared to coarse limestone (p < .05). The concentration of blood Ca was lower in birds who received supplemental coarse or fine oyster shell than coarse limestone (p < .05). Higher expression of calbindin gene observed in birds fed on the coarse oyster shell (p < .05). In experiment 2, a total of 360 Japanese quail assigned to experimental treatments of feeding: (1) control: a basal diet; (2) choice feeding between a Ca deficient diet and limestone with coarse (granulated) and fine particles; (3) choice feeding between a Ca deficient diet and oyster shell with coarse and fine particles. All birds preferred to use fine Ca particles across the first week of the experiment (p < .05) whereas tended to consume higher fine oyster shell during the entire rearing period (p < .05). Feed conversion ratio impaired in birds subjected to choice feeding (p < .05). Overall, coarse oyster shell decreased the growth of birds in the first experiment. The overall growth of choice-fed birds depressed compared to when received one conventional feed. HIGHLIGHTS Growth of quail decreased when they fed on diets containing coarse oyster shell. Higher expression of calbindin gene observed in quail received coarse oyster shell. Quail tended to use a separate source of Ca when fed with a Ca deficient diet.

Enteral Nutrition Support in Management of a Pediatric Patient with Secondary Acute Malnutrition and SARS-CoV-2 Infection : A Case Report

Severe acute malnutrition (SAM) contributes to about one million deaths annually in children under the age of 5 years. Secondary acute malnutrition is common in children with underlying medical conditions. It may pose a great risk in developing severe illness during SARS-CoV-2 infection among children. Proper implementation of nutrition care process is critical in management of secondary acute malnutrition among children in clinical settings. Eight months old male admitted with meningoencephalitis; septic shock, anemia, rickets, osteomyelitis, severe malnutrition and severe SARS-CoV-2 pneumonia complications. On admission, body temperature was 370C, random blood sugars were 17.5mmol/L and with saturation of 98% on room air. He had a body weight of 5.5kg on admission with a z-score of -3sd. Nutrition focused physical examination revealed severe loss of muscle mass and adipose tissue. Nutrition prescription of high calorie high protein diet providing 846 calories and 22.3 g of protein per day was prescribed. The feed of choice was fortified blended flour (FBF) porridge which was administered via nasogastric feeding tube. After fourteen days of nutrition care in the unit, the patient had a weight gain of 100g. The average weight gain rate was 1.29g/kg/day. This case report documents challenges in nutrition management of secondary acute malnutrition with SARS-CoV-2 pneumonia in resource limited clinical settings. The review of existing guidelines and disease specific nutrition commodities in the management of secondary acute malnutrition in clinical settings is recommended. Keywords: Enteral nutrition, Nutrition care process, Secondary acute malnutrition, SARS CoV2 infection, Covid19

Application of Theory of Characteristics Modes for Bandwidth Enhancement of a Miniaturized Minkowski Fractal Antenna

This article presents a miniaturized modified Minkowski fractal antenna with enhanced linearly polarized impedance bandwidth (IBW) in the lower frequency region. Applying theory of characteristic modes (TCM) analysis on a second iterated modified Minkowski radiator without feeding structure, modal currents and their corresponding modal fields (radiation patterns) were determined to recognize symmetric dominant modes to be specifically excited to generate the required radiation pattern. It gave direction for choosing quarter-wave microwave line feeding as the feed of choice to excite the four desired modes at 2.7, 5.7, 5.9, and 8.7 GHz and providing excellent impedance matching to generate the very wide IBW. Measured results matched well with simulations done using Ansys HFSS 2020R1. Measured IBW is 9.7 GHz (160%), from 1.2 to 10.9 GHz, with center resonance frequency (frc) at 6.05 GHz, whereas simulated IBW is 9.4 GHz (162%), from 1.1 to 10.5 GHz with frc at 5.8 GHz. The antenna size is 36 × 34 × 1.6 mm3 (0.216λgL × 0.204λgL where at lower resonating frequency frL = 1.1 GHz, λgL is the guided wavelength) with 82.24% reduction in size. This antenna may be utilized for “L”, “S” band and UWB wireless communication.