A functional division of Drosophila sweet taste neurons that is value-based and task-specific

Sucrose is an attractive feeding substance and a positive reinforcer for Drosophila. But Drosophila females have been shown to robustly reject a sucrose-containing option for egg-laying when given a choice between a plain and a sucrose-containing option in specific contexts. How the sweet taste system of Drosophila promotes context-dependent devaluation of an egg-laying option that contains sucrose, an otherwise highly appetitive tastant, is unknown. Here, we report that devaluation of sweetness/sucrose for egg-laying is executed by a sensory pathway recruited specifically by the sweet neurons on the legs of Drosophila. First, silencing just the leg sweet neurons caused acceptance of the sucrose option in a sucrose versus plain decision, whereas expressing the channelrhodopsin CsChrimson in them caused rejection of a plain option that was “baited” with light over another that was not. Analogous bidirectional manipulations of other sweet neurons did not produce these effects. Second, circuit tracing revealed that the leg sweet neurons receive different presynaptic neuromodulations compared to some other sweet neurons and were the only ones with postsynaptic partners that projected prominently to the superior lateral protocerebrum (SLP) in the brain. Third, silencing one specific SLP-projecting postsynaptic partner of the leg sweet neurons reduced sucrose rejection, whereas expressing CsChrimson in it promoted rejection of a light-baited option during egg-laying. These results uncover that the Drosophila sweet taste system exhibits a functional division that is value-based and task-specific, challenging the conventional view that the system adheres to a simple labeled-line coding scheme.

Low temperature triggers physiological and behavioral shifts in adult oriental armyworm, Mythimna separata

Migratory insects display diverse behavioral strategies in response to external environmental shifts, via energy allocation of migration-reproduction trade-offs. However, how migratory insects distribute energy between migration and reproduction as an adaptive strategy to confront temporary low temperatures remains unclear. Here, we used Mythimna separata, a migratory cereal crop pest, to explore the effects of low temperature on reproductive performance, behavior, and energy allocation. We found that the influence of low temperatures on reproduction was not absolutely negative, but instead depended on the intensity, duration, and age of exposure to low temperature. Exposure to 6°C for 24 h significantly accelerated the onset of oviposition and ovarian development, and increased the synchrony of egg-laying and lifetime fecundity in 1-day-old adults compared to the control, while female's flight capacity decreased significantly on the first and second day after moths were exposed to 6°C. Furthermore, the abdominal and total triglycerides levels of females decreased significantly from exposure to low temperature, but their thoracic triglyceride content was significantly higher than the control on the third and fourth day. These results indicated that low temperatures induced M. separata to reduce energy investment for the development of flight system. This resulted in the shifting of moths from being migrants to residents during the environmental sensitive period (first day post-emergence). This expands our understanding of the adaptive strategy employed by migratory insects to deal with low temperatures and aids in the management of this pest species in China.

Medullary bone in male budgerigars (Melopsittacus undulatus) with testicular neoplasms

Medullary bone is a calcium-rich, labile bone normally occurring in female birds with each egg-laying cycle. The stimulus for formation of medullary bone is, in part, the cyclic increase in serum estrogens produced by preovulatory ovarian follicles. Increased bone density due to formation of medullary bone, particularly in pneumatic bones, has been termed polyostotic hyperostosis, even if physiologic. This study investigated the formation of medullary bone in nonpneumatic (femur) and pneumatic (humerus) bones in sexually mature male budgerigars submitted for autopsy. Of the 21 sexually mature male budgerigars submitted for autopsy, 7 (33%) had medullary bone in 1 or more bones examined. All 7 male budgerigars with medullary bone had a testicular neoplasm, which was morphologically consistent with a testicular sustentacular cell tumor, seminoma, or interstitial cell tumor. Medullary bone was not present in the 14 cases with other diseases. Medullary bone formation in pneumatic and nonpneumatic bones can occur in male budgerigars with testicular neoplasms. Radiographic increases in medullary bone density, particularly in the humerus, could provide antemortem indication of testicular neoplasia in male budgerigars.

The importance of direct and indirect trophic interactions in determining the presence of a locally rare day-flying moth

Ecosystem engineers affect other organisms by creating, maintaining or modifying habitats, potentially supporting species of conservation concern. However, it is important to consider these interactions alongside non-engineering trophic pathways. We investigated the relative importance of trophic and non-trophic effects of an ecosystem engineer, red deer, on a locally rare moth, the transparent burnet (Zygaena purpuralis). This species requires specific microhabitat conditions, including the foodplant, thyme, and bare soil for egg-laying. The relative importance of grazing (i.e., trophic effect of modifying microhabitat) and trampling (i.e., non-trophic effect of exposing bare soil) by red deer on transparent burnet abundance is unknown. We tested for these effects using a novel method of placing pheromone-baited funnel traps in the field. Imago abundance throughout the flight season was related to plant composition, diversity and structure at various scales around each trap. Indirect effects of red deer activity were accounted for by testing red deer pellet and trail presence against imago abundance. Imago abundance was positively associated with thyme and plant diversity, whilst negatively associated with velvet grass and heather species cover. The presence of red deer pellets and trails were positively associated with imago abundance. The use of these sites by red deer aids the transparent burnet population via appropriate levels of grazing and the provision of a key habitat condition, bare soil, in the form of deer trails. This study shows that understanding how both trophic and non-trophic interactions affect the abundance of a species provides valuable insights regarding conservation objectives.

Advancements in Mass Rearing the Air Potato Beetle Lilioceris cheni

The air potato beetle, Lilioceris cheni Gressitt and Kimoto (Coleoptera:Chrysomelidae), is a successful biological control agent of the air potato vine, Dioscorea bulbifera L. (Dioscoreales: Dioscoreaceae), in the southern United States. Lilioceris cheni is currently being mass-reared by the Florida Department of Agriculture and Consumer Services Division of Plant Industry (FDACS-DPI) for biological control releases and research. The facility rears and releases over 50,000 adult beetles annually at approximately 1000 different locations. In addition to data on beetle production and distribution, studies on alternative larval and adult diets are described. Adults fed bulbils as the sole food source had reduced life spans compared with beetles given fresh air potato leaves. Adults survived without air potato leaves or bulbils for several days to two weeks depending on availability of leaves at emergence. Larvae did not survive on a modified artificial Colorado potato beetle diet containing fresh air potato vine leaves. Adults survived while consuming artificial diet but ceased oviposition. They, however, resumed egg laying less than one week after being returned to a diet of fresh air potato vine leaves.

Maternal investment evolves with larger body size and higher diversification rate in sharks and rays

Across vertebrates, live-bearing has evolved at least 150 times from the ancestral state of egg-laying into a diverse array of forms and degrees of prepartum maternal investment. A key question is how this diversity of reproductive modes arose and whether reproductive diversification underlies species diversification? To test these questions, we evaluate the most basal jawed vertebrates, Chondrichthyans, which have one of the greatest ranges of reproductive and ecological diversity among vertebrates. We reconstructed the sequence of reproductive mode evolution across a time-calibrated molecular phylogeny of 610 chondrichthyans. We find that egg-laying is ancestral, and that live-bearing evolved at least seven times. Matrotrophy (i.e. additional maternal contributions) evolved at least 15 times, with evidence of one reversal. In sharks, transitions to live-bearing and matrotrophy are more prevalent in larger-bodied species in the tropics. Further, the evolution of live-bearing is associated with a near-doubling of the diversification rate, but, there is only a small increase in diversification associated with the appearance of matrotrophy. The chondrichthyan diversification and radiation, particularly throughout the shallow tropical shelf seas and oceanic pelagic habitats, appears to be associated with the evolution of live-bearing and the proliferation of a wide range of maternal investment in their developing offspring.

System development for production of black soldier fly larvae (Hermetia illucens) in small scale, using wild flies

Technological innovation in rural areas guarantees the maintenance and subsistence of rural producers. Additionally, it is mandatory to use strategies aimed at reducing costs in animal production and reducing the environmental impact involved, making it challenging in the current global scenario. Thus, it is necessary to develop new alternative methods of production aimed at small scales, which can be implemented in small properties with reduced capital investment. In this sense, the objective was to describe the development of a system capable of inducing the production of black soldier fly larvae-BSFL (Hermetia illucens) through the attractiveness of egg laying of wild adults. To make the larvae production system, the following were needed: a plastic drum, with a capacity of 200 liters, 10 meters of 8mm silk rope, 1.5 m2 of wire mesh with 25mm x 20mm mesh, 1 m2 3mm x 2mm nylon mesh, plastic faucet for draining the slurry, one meter of 20mm diameter hose, two plastic containers with capacity of 20 liters for collecting the slurry and pre-pupae; besides equipment for cutting and finishing the drum. The System was supplied with organic plant material from daily household disposal, and other plant residues produced on the property. The development of this System can provide great social and economic viability, as it can be implemented in small rural properties for the treatment of organic waste. The mechanism presented good performance for the recycling of organic waste, and also for the production of BSFL, with satisfactory quantity collected daily.

Profil dan Keragaman Ayam Kub yang Dipelihara Oleh RTM Peternak dalam Program Bekerja di Kabupaten Indramayu

The aim of this study was to determine the diversity of KUB chickens raised by farmer households in Indramayu Regency in the implementation of the 2019 BEKERJA program. The BEKERJA program is carried out in 8.189 farmer households by providing 50 DOC, chicken feed during 5 weeks, maintenance support facilities include feed tray, drinking bottles, brooder cages, cables, lights, and cage subsidy for 4 weeks chickens. The parameters observed were the number of chicken mortality, age of first egg laying and the number of egg production for the first time. The observations showed that the mortality of KUB chickens increased at 3 months of raised, which was caused by the sale and slaughter of chickens and the mortality of chickens due to improper raise management. Hens that lay eggs early in the District of Anjatan and District of Bongas 7.066 and 1.041, respectively. The results of the study showed that there was diversity at the beginning of egg-laying chicken due to improper feeding management, but KUB chicken had the potential to be developed as an egg and meat producer in Indramayu Regency. Keywords: BEKERJA Program; Diversity at the beginning of egg-laying chicken; KUB chicken Abstrak Kajian bertujuan untuk mengetahui keragaman ayam KUB yang dipelihara oleh RTM di Kabupaten Indramayu dalam pelaksanaan program BEKERJA tahun 2019. Program BEKERJA melibatkan 8.189 RTM dengan memberikan bantuan 50 ekor DOC ayam KUB, pakan selama 5 minggu pemeliharaan, bantuan sarana prasarana pemeliharaan meliputi tray tempat pakan, botol tempat minum, kandang brooder, kabel, lampu, dan bantuan subsidi kandang untuk ayam umur 4 minggu. Parameter yang diamati adalah jumlah kematian ayam, umur bertelur pertama kali dan produksi telur pertama kali. Hasil pengamatan menunjukkan bahwa kematian ayam KUB meningkat pada 3 bulan usia pemeliharaan, yang disebabkan oleh penjualan dan pemotongan ayam serta kematian akibat manajemen pemeliharaan yang kurang tepat. Jumlah produksi telur pertama kali di Kecamatan Anjatan dan Kecamatan Bongas masing-masing sebesar 7.066 butir dan 1.041 butir. Hasil kajian menunjukkan adanya keragaman pada awal bertelur ayam yang diakibatkan oleh manajemen pemberian pakan yang tidak tepat, namun ayam KUB berpotensi dikembangkan sebagai penghasil telur dan daging di kabupaten Indramayu Kata kunci : Ayam KUB; Keragaman awal bertelur; Program BEKERJA

Modulation of sugar feeding behavior by Gymnema sylvestre in Drosophila melanogaster

Introduction: Sugar is the main source of energy for nearly all animals. However, consumption of a high amount of sugars can lead to many metabolic disorders hence, balancing calorie intake in the form of sugar is required. Various herbs are in use to control body weight, cure diabetes and control elevated blood sugar levels. One such herb is Gymnema sylvestre commonly called Gurmar (destroyer of sugar). Gurmar selectively inhibits sugar sensation by mechanisms that are still elusive. Objectives: The primary objective of this study is to understand the effect of gurmar on sweet taste feeding behaviour in insects using the invertebrate model system Drosophila melanogaster. Methods: For this study, we used feeding assays, spectrophotometry and Proboscis Extension Reflex (PER) assay to determine how flies detect gurmar. Additionally, life span analysis, egg-laying behaviour and developmental profiles were used to probe the role of gurmar on the overall health of the flies. During the whole study, we used only the raw powdered form of gurmar (dried leaves) to examine its effect on sweet taste feeding behaviour. Results: Our data demonstrate that whole gurmar in a raw powdered form is aversive to flies and inhibits sugar evoked PER and feeding responses. Also, we observed it takes at least 24 h of starvation time to reduce the consumption of sugar in flies pre-fed on gurmar. Flies lay a fewer number of eggs on gurmar media and show developmental defects. Our data suggest that flies detect gurmar using both taste and olfactory cues. Conclusion: Understanding how gurmar reshapes taste curves to promote reduced consumption of sugars in flies will open up avenues to help people with health issues related to high sugar consumption, but our data also highlights that its consumption should be carefully considered since gurmar is aversive to flies and has detrimental effects on development.